Datasheet ADIS16488 Datasheet (ANALOG DEVICES)

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Page 1

Ten Degrees of Freedom Inertial Sensor

ADIS16488

Rev. B

Trademarks and registered trademarks are the prop erty of their respective owner s.

CONTROLLLER

CLOCK

TRIAXIAL

GYRO

TRIAXIAL

ACCEL

POWER

MANAGEMENT

SCLK

DIN

DOUT

GND

VDD

TEMP

VDD

DIO1 DIO2 DIO3 DIO4

VDDRTC

RST

SPI

TRIAXIAL

MAGN

PRESSURE

SELF-TEST I/O ALARMS

OUTPUT

DATA

REGISTERS

USER

CONTROL

REGISTERS

CALIBRATION

AND

FILTERS

ADIS16488

10277-001

Data Sheet

FEATURES

Triaxial, digital gyroscope, ±450°/sec dynamic range

<±0.05° orthogonal alignment 6°/hr in-run bias stability

0.3°/√hr angular random walk

0.01% nonlinearity Triaxial, digital accelerometer, ±18 g Triaxial, delta angle and delta velocity outputs Triaxial, digital magnetometer, ±2.5 gauss Digital pressure sensor, 300 mbar to 1100 mbar Fast start-up time, ~500 ms Factory-calibrated sensitivity, bias, and axial alignment

Calibration temperature range: −40°C to +70°C SPI-compatible serial interface Embedded temperature sensor Programmable operation and control

Automatic and manual bias correction controls

4 FIR filter banks, 120 configurable taps

Digital I/O: data-ready alarm indicator, external clock

Alarms for condition monitoring

Power-down/sleep mode for power management

Optional external sample clock input: up to 2.4 kHz

Single-command self-test Single-supply operation: 3.0 V to 3.6 V 2000 g shock survivability Operating temperature range: −40°C to +85°C

Tactical Grade

GENERAL DESCRIPTION

The ADIS16488 iSensor® device is a complete inertial system that includes a triaxis gyroscope, a triaxis accelerometer, triaxis magnetometer, and pressure sensor. Each inertial sensor in the

ADIS16488 combines industry-leading iMEMS® technology

with signal conditioning that optimizes dynamic performance. The factory calibration characterizes each sensor for sensitivity, bias, alignment, and linear acceleration (gyroscope bias). As a result, each sensor has its own dynamic compensation formulas that provide accurate sensor measurements.

The ADIS16488 provides a simple, cost-effective method for integrating accurate, multiaxis inertial sensing into industrial systems, especially when compared with the complexity and investment associated with discrete designs. All necessary motion testing and calibration are part of the production process at the factory, greatly reducing system integration time. Tight orthogonal alignment simplifies inertial frame alignment in navigation systems. The SPI and register structure provide a simple interface for data collection and configuration control.

The ADIS16488 uses the same footprint and connector system as the ADIS16375, which greatly simplifies the upgrade process. It comes in a module that is approximately 47 mm × 44 mm × 14 mm and has a standard connector interface.

APPLICATIONS

Platform stabilization and control Navigation Personnel tracking Instrument Robotics

FUNCTIONAL BLOCK DIAGRAM

Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices.

Figure 1.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com

Page 2

ADIS16488 Data Sheet

Features .............................................................................................. 1

Applications ....................................................................................... 1

General Description ......................................................................... 1

Functional Block Diagram .............................................................. 1

Revision History ............................................................................... 2

Specifications ..................................................................................... 3

Timing Specifications .................................................................. 5

Absolute Maximum Ratings ............................................................ 6

ESD Caution .................................................................................. 6

Pin Configuration and Function Descriptions ............................. 7

Typical Performance Characteristics ............................................. 8

Basic Operation ................................................................................. 9

SPI Communication ................................................................... 10

Device Configuration ................................................................ 10

Reading Sensor Data .................................................................. 10

User Registers .................................................................................. 11

Output Data Registers .................................................................... 14

Inertial Sensor Data Format ...................................................... 14

Rotation Rate (Gyroscope) ........................................................ 14

Acceleration ................................................................................. 15

Delta Angles ................................................................................ 15

Delta Velocity .............................................................................. 16

Magnetometers ........................................................................... 17

Barometer .................................................................................... 17

Internal Temperature ................................................................. 17

Status/Alarm Indicators ............................................................. 18

Firmware Revision ..................................................................... 19

Product Identification ................................................................ 19

Digital Signal Processing ............................................................... 20

Gyroscopes/Accelerometers ..................................................... 20

Averaging/Decimation Filter .................................................... 20

Magnetometer/Barometer ......................................................... 20

FIR Filter Banks .......................................................................... 21

Calibration ....................................................................................... 23

Gyroscopes .................................................................................. 23

Accelerometers ........................................................................... 24

Magnetometers ........................................................................... 24

Barometers .................................................................................. 26

Restoring Factory Calibration .................................................. 26

Point of Percussion Alignment ................................................. 26

Alarms .............................................................................................. 27

Static Alarm Use ......................................................................... 27

Dynamic Alarm Use .................................................................. 27

System Controls .............................................................................. 29

Global Commands ..................................................................... 29

Memory Management ............................................................... 29

General-Purpose I/O ................................................................. 29

Power Management ................................................................... 30

Applications Information .............................................................. 32

Prototype Interface Board ......................................................... 32

Installation Tips .......................................................................... 32

Outline Dimensions ....................................................................... 33

Ordering Guide .......................................................................... 33

REVISION HISTORY

2/12—Rev. A to Rev. B

Change to Features Section ............................................................. 1

Changes to Table 3 ............................................................................ 6

Changes to Figure 7 and Figure 8 ................................................... 8

Changes to Delta Angles Section .................................................. 15

Changes to Delta Velocity Section, Table 31, Table 32, Table 33,

and Table 34 ..................................................................................... 16

Change to Status/Alarm Indicators Section ................................ 18

Changes to Gyroscopes/Accelerometers Section, Averaging/Decimation Filter Section, Magnetometer/Barometer

Section, and Figure 20 .................................................................... 20

Changes to Input Sync/Clock Control Section ........................... 30

Rev. B | Page 2 of 36

Changes to Prototype Interface Board Section and

Figure 26 .......................................................................................... 30

12/11—Rev. 0 to Rev. A

Changes to Specifications Section ................................................... 3

Changes to System/Alarm Indicators Section ............................ 18

Changes to Averaging/Decimation Filter Section ...................... 20

Changes to General-Purpose I/O Section ................................... 29

Changes to Input Sync/Clock Control Section...........................

10/11—Revision 0: Initial Version

Page 3

Data Sheet ADIS16488

Axis-to-frame (package)

±1.0 Degrees

Linear Acceleration Effect on Bias

Any axis, 1 σ (CONFIG[7] = 1)

0.009

°/sec/g

Initial Sensitivity Tolerance

±0.5

Initial Bias Error

1 σ ±16 mg

MAGNETOMETER

SPECIFICATIONS

TA = 25°C, VDD = 3.3 V, angular rate = 0°/sec, dynamic range = ±450°/sec ± 1 g, 300 mbar to 1100 mbar, unless otherwise noted.

Table 1.

Parameter Test Conditions/Comments Min Typ Max Unit

GYROSCOPES

Dynamic Range ±450 ±480 °/sec

Sensitivity x_GYRO_OUT and x_GYRO_LOW (32-bit) 3.052 × 10−7 °/sec/LSB

Initial Sensitivity Tolerance ±1 %

Sensitivity Temperature Coefficient −40°C ≤ TA ≤ +70°C, 1 σ ±35 ppm/°C

Misalignment Axis-to-axis ±0.05 Degrees

Nonlinearity Best-fit straight line, FS = 450°/sec 0.01 % of FS

Initial Bias Error 1 σ ±0.2 °/sec

In-Run Bias Stability 1 σ 6.25 °/hr

Angular Random Walk 1 σ 0.3 °/√hr

Bias Temperature Coefficient −40°C ≤ TA ≤ +70°C, 1 σ ±0.0025 °/sec/°C

Output Noise No filtering 0.16 °/sec rms

Rate Noise Density f = 25 Hz, no filtering 0.0066 °/sec/√Hz rms

3 dB Bandwidth 330 Hz

Sensor Resonant Frequency 18 kHz

ACCELEROMETERS Each axis

Dynamic Range ±18

Sensitivity x_ACCL_OUT and x_ACCL_LOW (32-bit) 1.221 × 10−8 g/LSB

Sensitivity Temperature Coefficient −40°C ≤ TA ≤ +85°C, 1 σ ±25 ppm/°C

Misalignment Axis-to-axis ±0.035 Degrees

Axis-to-frame (package) ±1.0 Degrees

Nonlinearity Best-fit straight line, ±10 g 0.1 % of FS

Best-fit straight line, ±18 g 0.5 % of FS

In-Run Bias Stability 1 σ 0.1 mg

Velocity Random Walk 1 σ 0.029 m/sec/√hr

Bias Temperature Coefficient −40°C ≤ TA ≤ +85°C ±0.1 mg/°C

Output Noise No filtering 1.5 mg rms

Noise Density f = 25 Hz, no filtering 0.067 mg/√Hz rms

3 dB Bandwidth 330 Hz

Sensor Resonant Frequency 5.5 kHz

Dynamic Range

Sensitivity

Initial Sensitivity Tolerance

Sensitivity Temperature Coefficient

Misalignment Axis to axis 0.25 Degrees

Axis to frame (package) 0.5 Degrees

Nonlinearity Best fit straight line 0.5 % of FS

Initial Bias Error 0 gauss stimulus ±15 mgauss

Bias Temperature Coefficient −40°C ≤ TA ≤ +85°C, 1 σ 0.3 mgauss/°C

Output Noise

Noise Density

3 dB Bandwidth 330 Hz

±2.5 gauss

0.1 mgauss/LSB ±2 % 1 σ 275 ppm/°C

No filtering f = 25 Hz, no filtering

0.45 mgauss

0.054 mgauss/√Hz

Rev. B | Page 3 of 36

Page 4

ADIS16488 Data Sheet

Error with Supply

0.04 %/V

Noise

0.025

mbar rms

Input Capacitance, CIN

10 pF

Output Low Voltage, VOL

= 2.0 mA

0.4

Power-down mode, VDD = 3.3 V

45 µA

Parameter Test Conditions/Comments Min Typ Max Unit

BAROMETER

Pressure Range 300 1100 mbar

Extended 10 1200 mbar

Sensitivity BAROM_OUT and BAROM_LOW (32-bit) 6.1 × 10−7 mbar/LSB

Total Error 4.5 mbar Relative Error1 −40°C to +85°C 2.5 mbar Linearity2 Best fit straight line, FS = 1100 mbar 0.1 % of FS

−40°C to +85°C 0.2 % of FS

Linear-g Sensitivity ±1 g, 1 σ 0.005 mbar/g

TEMPERATURE SENSOR

Scale Factor Output = 0x0000 at 25°C (±5°C) 0.00565 °C/LSB

LOGIC INPUTS3

Input High Voltage, VIH 2.0 V Input Low Voltage, VIL 0.8 V CS Wake-Up Pulse Width Logic 1 Input Current, IIH VIH = 3.3 V 10 µA Logic 0 Input Current, IIL VIL = 0 V

All Pins Except RST RST Pin

20 µs

10 µA

0.33 mA

DIGITAL OUTPUTS

Output High Voltage, VOH I

= 0.5 mA 2.4 V

SOURCE

SINK

FLASH MEMORY Endurance4 100,000 Cycles

Data Retention5 TJ = 85°C 20 Ye ars

FUNCTIONAL TIMES6 Time until data is available

Power-On Start-up Time 500 ms Reset Recovery Time 500 ms Sleep Mode Recovery Time 500 µs Flash Memory Update Time 375 ms Flash Memory Test Time 50 ms Automatic Self-Test Time Using internal clock, 100 SPS 12 ms

CONVERSION RATE 2.46 kSPS

Initial Clock Accuracy 0.02 % Temperature Coefficient 40 ppm/°C Sync Input Clock 0.77 2.4 kHz

POWER SUPPLY, VDD Operating voltage range 3.0 3.6 V

Power Supply Current8 Normal mode, VDD = 3.3 V, µ ± σ 254 mA Sleep mode, VDD = 3.3 V 12.2 mA

POWER SUPPLY, VDDRTC Operating voltage range 3.0 3.6 V

Real-Time Clock Supply Current Normal mode, VDDRTC = 3.3 V 13 µA

The relative error assumes that the initial error, at 25°C, is corrected in the end application.

Linearity errors assume a full scale (FS) of 1000 mbar.

The digital I/O signals are driven by an internal 3.3 V supply, and the inputs are 5 V tolerant.

Endurance is qualified as per JEDEC Standard 22, Method A117, and measured at −40°C, +25°C, +85°C, and +125°C.

The data retention specification assumes a junction temperature (TJ) of 85°C as per JEDEC Standard 22, Method A117. Data retention lifetime decreases with TJ.

These times do not include thermal settling and internal filter response times, which may affect overall accuracy.

Device functions at clock rates below 0.7 kHz, but at reduced performance levels.

Supply current transients can reach 450 mA for 400 µs during start-up and reset recovery.

Rev. B | Page 4 of 36

Page 5

Data Sheet ADIS16488

Serial clock high period

DIN setup time before SCLK rising edge

SCLK

DOUT

DIN

1 2 3 4 5 6 15 16

R/W A5A6 A4 A3 A2

MSB

DB14

D1 LSB

DB13 DB12 DB10DB11 DB2 LSBDB1

DSHI

DAV

CHS

CLS

DSOE

DHD

DSU

10277-002

SCLK

STALL

10277-003

SYNC

CLOCK (CLKIN)

DATA

READY

OUTPUT

REGISTERS

10277-004

DATA VALID DATA VALID

TIMING SPECIFICATIONS

TA = 25°C, VDD = 3.3 V, unless otherwise noted.

Table 2.

Normal Mode Parameter Description Min1 Typ Max1 Unit

Serial clock 0.01 15 MHz

SCLK

Stall period between data 2 µs

STA LL

Serial clock low period 31 ns

CLS

CHS

tCS Chip select to clock edge 32 ns t

DOUT valid after SCLK edge 10 ns

DAV

DSU

DIN hold time after SCLK rising edge 2 ns

DHD

tDR, tDF DOUT rise/fall times, ≤100 pF loading 3 8 ns t

DSOE

CS assertion to data out active tHD SCLK edge to data out invalid 0 ns t

DSHI

Guaranteed by design and characterization, but not tested in production.

CS deassertion to data out high impedance

Input sync pulse width 5 µs

Input sync to data-ready output 490 µs

Input sync period 417 µs

0 11 ns

0 9 ns

Timing Diagrams

Figure 2. SPI Timing and Sequence

Figure 3. Stall Time and Data Rate

Figure 4. Input Clock Timing Diagram

Rev. B | Page 5 of 36

Page 6

ADIS16488 Data Sheet

Any Axis, Unpowered

2000 g

Storage Temperature Range

−65°C to +150°C

24-Lead Module (ML-24-6)

22.8°C/W

10.1°C/W

48 g

ABSOLUTE MAXIMUM RATINGS

Table 3.

Parameter Rating

Acceleration

Any Axis, Powered 2000 g VDD to GND −0.3 V to +3.6 V Digital Input Voltage to GND −0.3 V to VDD + 0.2 V Digital Output Voltage to GND −0.3 V to VDD + 0.2 V Operating Temperature Range −40°C to +85°C

Barometric Pressure 6 bar

Extended exposure to temperatures that are lower than −40°C or higher

than +105°C can adversely affect the accuracy of the factory calibration.

Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

Table 4. Package Characteristics

Device

Package Type θJA θJC

Weight

ESD CAUTION

Rev. B | Page 6 of 36

Page 7

Data Sheet ADIS16488

DIO3

SCLK

DIN

DIO1

DIO2

VDD

GND

DNC

VDDRTC

DIO4

DOUT

RST

VDD

GND

DNC

3456789

ADIS16488

TOP VIEW

(Not to S cale)

NOTES

1. THIS REPRESENTATION DISPLAYS T HE TOP VIEW PINOUT FOR THE MATING SO CKE T CONNECTOR.

2. THE ACTUAL CONNEC TO R P INS ARE NOT VISIBLE FROM THE TOP VIEW.

3. MATING CONNECTOR: SAMTEC CLM-112-02 OR EQUIVALENT.

4. DNC = DO NOT CONNECT TO THESE PINS.

10277-005

10277-006

PIN 1

PIN 23

DIO4

Input/output

Configurable Digital Input/Output.

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

Figure 5. Mating Connector Pin Assignments

Figure 6. Axial Orientation (Top Side Facing Up)

Table 5. Pin Function Descriptions

Pin No. Mnemonic Type Description

1 DIO3 Input/output Configurable Digital Input/Output.

3 SCLK Input SPI Serial Clock. 4 DOUT Output SPI Data Output. Clocks output on SCLK falling edge. 5 DIN Input SPI Data Input. Clocks input on SCLK rising edge. 6

Input SPI Chip Select.

7 DIO1 Input/output Configurable Digital Input/Output. 8

RST

Input Reset. 9 DIO2 Input/output Configurable Digital Input/Output. 10, 11, 12 VDD Supply Power Supply. 13, 14, 15 GND Supply Power Ground. 16 to 22, 24 DNC Not applicable Do Not Connect to These Pins. 23 VDDRTC Supply Real-Time Clock Power Supply.

Rev. B | Page 7 of 36

Page 8

ADIS16488 Data Sheet

1000

100

0.01 0.1 1 10 100 1000 10000

ROOT AL LAN VARIANCE (° /Hour)

INTEGRATION PERIOD (Seconds)

10277-007

+1σ

–1σ

AVERAGE

0.001

0.00001

0.0001

0.01 0.1 1 10 100 1000 10000

ROOT AL LAN VARIANCE (g)

INTEGRATION PERIOD (Seconds)

10277-008

+1σ

–1σ

AVERAGE

0.8

–0.8

–0.6

–0.4

–0.2

0.2

0.4

0.6

–40 –30 –20 –10 0 10 20 30 40 50 60 70 80

GYRO SCAL E E RROR (% FS)

TEMPERATURE (°C)

10277-109

INITI AL ERROR = ±0.5% TEMPCO = 35ppm/°C

0.6

–0.6

–0.5

–0.4

–0.3

–0.2

–0.1

0.1

0.2

0.3

0.4

0.5

–40 –30 –20 –10 0 10 20 30 40 50

60 70 80

GYRO BIAS E RROR (°/sec)

TEMPERATURE (°C)

10277-110

INITI AL ERROR = ±0.2°/sec TEMPCO = 0.0025°/sec/°C

TYPICAL PERFORMANCE CHARACTERISTICS

Figure 7. Gyroscope Allan Variance, 25°C

Figure 8. Accelerometer Allan Variance, 25°C

Figure 9. Gyroscope Scale (Sensitivity) Error and Hysteresis vs. Temperature

Figure 10. Gyroscope Bias Error and Hysteresis vs. Temperature

Rev. B | Page 8 of 36

Page 9

Data Sheet ADIS16488

BASIC OPERATION

The ADIS16488 is an autonomous sensor system that starts up on its own when it has a valid power supply. After running through its initialization process, it begins sampling, processing, and loading calibrated sensor data into the output registers, which are accessible using the SPI port. The SPI port typically connects to a compatible port on an embedded processor, using the connection diagram in Figure 11. The four SPI signals facilitate synchronous, serial data communication. Connect

RST

(see Table 5) to VDD or leave it open for normal operation. The factory default configuration provides users with a data-ready signal on the DIO2 pin, which pulses high when new data is available in the output data registers.

VDD

SYSTEM PROCESSOR SPI MASTER

I/O LINES ARE COMPATIBLE WITH

3.3V LOGIC LEVELS

SCLK

MOSI MISO

IRQ DIO2

Figure 11. Electrical Connection Diagram

CS SCLK DIN DOUT

13 14 15

+3.3V

11 12 23

ADIS16488

10277-009

Table 6. Generic Master Processor Pin Names and Functions

Mnemonic Function

Slave select IRQ Interrupt request MOSI Master output, slave input MISO Master input, slave output SCLK Serial clock

Embedded processors typically use control registers to configure their serial ports for communicating with SPI slave devices such as the ADIS16488. Table 7 provides a list of settings, which describe the SPI protocol of the ADIS16488. The initialization routine of the master processor typically establishes these settings using firmware commands to write them into its serial control registers.

Table 7. Generic Master Processor SPI Settings

Processor Setting Description

Master The ADIS16488 operates as a slave. SCLK ≤ 15 MHz Maximum serial clock rate. SPI Mode 3 CPOL = 1 (polarity), and CPHA = 1 (phase). MSB-First Mode Bit sequence. 16-Bit Mode Shift register/data length.

REGISTER STRUCTURE

The register structure and SPI port provide a bridge between the sensor processing system and an external, master processor. It contains both output data and control registers. The output data registers include the latest sensor data, a real-time clock, error flags, alarm flags, and identification data. The control registers include sample rate, filtering, input/output, alarms, calibration, and diagnostic configuration options. All communication between the ADIS16488 and an external processor involves either reading or writing to one of the user registers.

TRIAXIS

GYRO

TRIAXIS

ACCEL

TRIAXIS

MAGN BARO

TEMP

SENSOR

CONTROLLER

Figure 12. Basic Operation

DSP

The register structure uses a paged addressing scheme that is composed of 13 pages, with each one containing 64 register locations. Each register is 16 bits wide, with each byte having its own unique address within that page’s memory map. The SPI port has access to one page at a time, using the bit sequence in Figure 17. Select the page to activate for SPI access by writing its code to the PAGE_ID register. Read the PAGE_ID register to determine which page is currently active. Table 8 displays the PAGE_ID contents for each page, along with their basic functions. The PAGE_ID register is located at Address 0x00 on every page.

Table 8. User Register Page Assignments

Page PAGE_ID Function

0 0x00 Output data, clock, identification 1 0x01 Reserved 2 0x02 Calibration 3 0x03 Control: sample rate, filtering, I/O, alarms 4 0x04 Serial number 5 0x05 FIR Filter Bank A Coefficient 0 to Coefficient 59 6 0x06 FIR Filter Bank A, Coefficient 60 to Coefficient 119 7 0x07 FIR Filter Bank B, Coefficient 0 to Coefficient 59 8 0x08 FIR Filter Bank B, Coefficient 60 to Coefficient 119 9 0x09 FIR Filter Bank C, Coefficient 0 to Coefficient 59 10 0x0A FIR Filter Bank C, Coefficient 60 to Coefficient 119 11 0x0B FIR Filter Bank D, Coefficient 0 to Coefficient 59 12 0x0C FIR Filter Bank D, Coefficient 60 to Coefficient 119

OUTPUT

REGISTERS

CONTROL

REGISTERS

SPI

10277-010

Rev. B | Page 9 of 36

Page 10

ADIS16488 Data Sheet

10277-011

SCLK

DIN

DIN = 1000 0000 0000 0011 = 0x8003, WRITES 0x03 TO ADDRESS 0x00

NONVOLATILE

FLASH MEMORY

(NO SPI ACCESS)

MANUAL

FLASH

BACKUP

START-UP

RESET

VOLATILE

SRAM

SPI ACCESS

10277-012

DIN

DOUT

0x1A00 0x1800

ADDRESS

Z_GYRO_OUT Z_GYRO_LOW

10277-013

SCLK

DIN

DOUT

DOUT = 0100 0000 0110 1000 = 0x4068 = 16, 488 ( P ROD_ID)

DIN = 0111 1110 0000 0000 = 0x7E00

10277-014

10277-015

R/W

A6 A5 A4 A3 A2 A1 A0 DC7 DC6 DC5 DC4 DC3 DC2 DC1 DC0

D0D1D2D3D4D5D6D7D8D9D10D11D12D13D14D15

SCLK

DIN

DOUT

A6 A5

D13D14D15

NOTES

1. DOUT BITS ARE PRO DUCE D ONLY WHEN THE PREVIOUS 16-BIT DI N S E QUENCE START S WITH R/W = 0.

2. WHEN CS IS HIGH, DOUT IS IN A THREE-STATE, HIGH IMPEDANCE MODE, WHICH ALLOWS MULTIFUNCTIONAL USE OF THE LINE FOR OT HE R DE V ICES.

SPI COMMUNICATION

The SPI port supports full duplex communication, as shown in Figure 17, which enables external processors to write to DIN while reading DOUT, if the previous command was a read request. Figure 17 provides a guideline for the bit coding on both DIN and DOUT.

DEVICE CONFIGURATION

The SPI provides write access to the control registers, one byte at a time, using the bit assignments shown in Figure 17. Each register has 16 bits, where Bits[7:0] represent the lower address (listed in Tabl e 9) and Bits[15:8] represent the upper address. Write to the lower byte of a register first, followed by a write to its upper byte second. The only register that changes with a single write to its lower byte is the PAGE_ID register. For a write command, the first bit in the DIN sequence is set to 1. Address Bits[A6:A0] represent the target address, and Data Command Bits[DC7:DC0] represent the data being written to the location. Figure 13 provides an example of writing 0x03 to Address 0x00 (PAG E_ I D [7:0]), using DIN = 0x8003. This write command activates the control page for SPI access.

Figure 13. SPI Sequence for Activating the Control Page (DIN = 0x8003)

Dual Memory Structure

Writing configuration data to a control register updates its SRAM contents, which are volatile. After optimizing each relevant control register setting in a system, use the manual flash update command, which is located in GLOB_CMD[3] on Page 3 of the register map. Activate the manual flash update command by turning to Page 3 (DIN = 0x8003) and setting GLOB_CMD[3] = 1 (DIN = 0x8208, then DIN = 0x8300). Make sure that the power supply is within specification for the entire 375 ms processing time for a flash memory update. Ta b le 9 provides a memory map for all of the user registers, which includes a column of flash backup information. A yes in this column indicates that a register has a mirror location in flash and, when backed up properly, automatically restores itself during startup or after a reset. Figure 14 provides a diagram of the dual memory structure used to manage operation and store critical user settings.

Figure 14. SRAM and Flash Memory Diagram

READING SENSOR DATA

The ADIS16488 automatically starts up and activates Page 0 for data register access. Write 0x00 to the PAGE_ID register (DIN = 0x8000) to activate Page 0 for data access after accessing any other page. A single register read requires two 16-bit SPI cycles. The first cycle requests the contents of a register using the bit assignments in Figure 17, and then the register contents follow DOUT during the second sequence. The first bit in a DIN command is zero, followed by either the upper or lower address for the register. The last eight bits are don’t care, but the SPI requires the full set of 16 SCLKs to receive the request. Figure 15 includes two register reads in succession, which starts with DIN = 0x1A00 to request the contents of the Z_GYRO_OUT register and follows with 0x1800 to request the contents of the Z_GYRO_LOW register.

Figure 15. SPI Read Example

Figure 16 provides an example of the four SPI signals when reading PROD_ID in a repeating pattern. This is a good pattern to use for troubleshooting the SPI interface setup and communications because the contents of PROD_ID are predefined and stable.

Figure 16. SPI Read Example, Second 16-Bit Sequence

Figure 17. SPI Communication Bit Sequence

Rev. B | Page 10 of 36

Page 11

Data Sheet ADIS16488

Name

R/W

Flash

PAGE_ID

Address

Default

Format

Reserved

N/A

0x00

0x02 to 0x04

N/A

Reserved

N/A

X_GYRO_LOW

0x00

0x10

N/A

Output, x-axis gyroscope, low word

Table 14

X_ACCL_LOW

0x00

0x1C

N/A

Output, x-axis accelerometer, low word

Table 21

Z_ACCL_OUT

0x00

0x26

N/A

Output, z-axis accelerometer, high word

Table 19

Reserved

N/A

0x00

0x32 to 0x3E

N/A

Reserved

N/A

Z_DELTVEL_LOW

0x00

0x54

N/A

Output, z-axis delta velocity, low word

Table 37

Y_GYRO_SCALE

R/W

Yes

0x02

0x06

0x0000

Calibration, scale, y-axis gyroscope

Table 72

USER REGISTERS

Table 9. User Register Memory Map (N/A = Not Applicable)

PAGE_ID R/W No 0x00 0x00 0x00 Page identifier N/A

SEQ_CNT R No 0x00 0x06 N/A Sequence counter Table 56 SYS_E_FLAG R No 0x00 0x08 0x0000 Output, system error flags Table 47 DIAG_STS R No 0x00 0x0A 0x0000 Output, self-test error flags Table 48 ALM_STS R No 0x00 0x0C 0x0000 Output, alarm error flags Table 49 TEMP_OUT R No 0x00 0x0E N/A Output, temperature Table 45

X_GYRO_OUT R No 0x00 0x12 N/A Output, x-axis gyroscope, high word Table 10 Y_GYRO_LOW R No 0x00 0x14 N/A Output, y-axis gyroscope, low word Table 15 Y_GYRO_OUT R No 0x00 0x16 N/A Output, y-axis gyroscope, high word Table 11 Z_GYRO_LOW R No 0x00 0x18 N/A Output, z-axis gyroscope, low word Table 16 Z_GYRO_OUT R No 0x00 0x1A N/A Output, z-axis gyroscope, high word Table 12

X_ACCL_OUT R No 0x00 0x1E N/A Output, x-axis accelerometer, high word Table 17 Y_ACCL_LOW R No 0x00 0x20 N/A Output, y-axis accelerometer, low word Table 22 Y_ACCL_OUT R No 0x00 0x22 N/A Output, y-axis accelerometer, high word Table 18 Z_ACCL_LOW R No 0x00 0x24 N/A Output, z-axis accelerometer, low word Table 23

X_MAGN_OUT R No 0x00 0x28 N/A Output, x-axis magnetometer, high word Table 38 Y_MAGN_OUT R No 0x00 0x2A N/A Output, y-axis magnetometer, high word Table 39 Z_MAGN_OUT R No 0x00 0x2C N/A Output, z-axis magnetometer, high word Table 40 BAROM_LOW R No 0x00 0x2E N/A Output, barometer, low word Table 44 BAROM_OUT R No 0x00 0x30 N/A Output, barometer, high word Table 42

X_DELTANG_LOW R No 0x00 0x40 N/A Output, x-axis delta angle, low word Table 28 X_DELTANG_OUT R No 0x00 0x42 N/A Output, x-axis delta angle, high word Table 24 Y_DELTANG_LOW R No 0x00 0x44 N/A Output, y-axis delta angle, low word Table 29 Y_DELTANG_OUT R No 0x00 0x46 N/A Output, y-axis delta angle, high word Table 25 Z_DELTANG_LOW R No 0x00 0x48 N/A Output, z-axis delta angle, low word Table 30 Z_DELTANG_OUT R No 0x00 0x4A N/A Output, z-axis delta angle, high word Table 26 X_DELTVEL_LOW R No 0x00 0x4C N/A Output, x-axis delta velocity, low word Table 35 X_DELTVEL_OUT R No 0x00 0x4E N/A Output, x-axis delta velocity, high word Table 31 Y_DELTVEL_LOW R No 0x00 0x50 N/A Output, y-axis delta velocity, low word Table 36 Y_DELTVEL_OUT R No 0x00 0x52 N/A Output, y-axis delta velocity, high word Table 32

Z_DELTVEL_OUT R No 0x00 0x56 N/A Output, z-axis delta velocity, high word Table 33 Reserved N/A N/A 0x00 0x58 to 0x76 N/A Reserved N/A TIME_MS_OUT R Yes 0x00 0x78 N/A Factory configuration time: minutes/seconds Table 124 TIME_DH_OUT R Yes 0x00 0x7A N/A Factory configuration date/time: day/hour Table 125 TIME_YM_OUT R Yes 0x00 0x7C N/A Factory configuration date: year/month Table 126 PROD_ID R Yes 0x00 0x7E 0x4068 Output, product identification (16,488) Table 53 Reserved N/A N/A 0x01 0x00 to 0x7E N/A Reserved N/A PAGE_ID R/W No 0x02 0x00 0x00 Page identifier N/A Reserved N/A N/A 0x02 0x02 N/A Reserved N/A X_GYRO_SCALE R/W Yes 0x02 0x04 0x0000 Calibration, scale, x-axis gyroscope Table 71

Z_GYRO_SCALE R/W Yes 0x02 0x08 0x0000 Calibration, scale, z-axis gyroscope Table 73 X_ACCL_SCALE R/W Yes 0x02 0x0A 0x0000 Calibration, scale, x-axis accelerometer Table 81 Y_ACCL_SCALE R/W Yes 0x02 0x0C 0x0000 Calibration, scale, y-axis accelerometer Table 82 Z_ACCL_SCALE R/W Yes 0x02 0x0E 0x0000 Calibration, scale, z-axis accelerometer Table 83

Rev. B | Page 11 of 36

Page 12

ADIS16488 Data Sheet

Name

R/W

Flash

PAGE_ID

Address

Default

Format

ZA_BIAS_LOW

R/W

Yes

0x02

0x24

0x0000

Calibration, offset, accelerometer, z-axis, low word

Table 80

SOFT_IRON_S31

R/W

Yes

0x02

0x3A

0x0000

Calibration, soft iron, magnetometer, S31

Table 94

USER_SCR_1

R/W

Yes

0x02

0x74

0x0000

User Scratch Register 1

Table 120

CONFIG

R/W

Yes

0x03

0x0A

0x00C0

Control, clock, and miscellaneous correction

Table 74

Reserved

N/A

0x03

0x26

N/A

Reserved

N/A

XG_BIAS_LOW R/W Yes 0x02 0x10 0x0000 Calibration, offset, gyroscope, x-axis, low word Table 67 XG_BIAS_HIGH R/W Yes 0x02 0x12 0x0000 Calibration, offset, gyroscope, x-axis, high word Table 64 YG_BIAS_LOW R/W Yes 0x02 0x14 0x0000 Calibration, offset, gyroscope, y-axis, low word Table 68 YG_BIAS_HIGH R/W Yes 0x02 0x16 0x0000 Calibration, offset, gyroscope, y-axis, high word Table 65 ZG_BIAS_LOW R/W Yes 0x02 0x18 0x0000 Calibration, offset, gyroscope, z-axis, low word Table 69 ZG_BIAS_HIGH R/W Yes 0x02 0x1A 0x0000 Calibration, offset, gyroscope, z-axis, high word Table 66 XA_BIAS_LOW R/W Yes 0x02 0x1C 0x0000 Calibration, offset, accelerometer, x-axis, low word Table 78 XA_BIAS_HIGH R/W Yes 0x02 0x1E 0x0000 Calibration, offset, accelerometer, x-axis, high word Table 75 YA_BIAS_LOW R/W Yes 0x02 0x20 0x0000 Calibration, offset, accelerometer, y-axis, low word Table 79 YA_BIAS_HIGH R/W Yes 0x02 0x22 0x0000 Calibration, offset, accelerometer, y-axis, high word Table 76

ZA_BIAS_HIGH R/W Yes 0x02 0x26 0x0000 Calibration, offset, accelerometer, z-axis, high word Table 77 HARD_IRON_X R/W Ye s 0x02 0x28 0x0000 Calibration, hard iron, magnetometer, x-axis Table 84 HARD_IRON_Y R/W Yes 0x02 0x2A 0x0000 Calibration, hard iron, magnetometer, y-axis Table 85 HARD_IRON_Z R/W Yes 0x02 0x2C 0x0000 Calibration, hard iron, magnetometer, z-axis Table 86 SOFT_IRON_S11 R/W Yes 0x02 0x2E 0x0000 Calibration, soft iron, magnetometer, S11 Table 88 SOFT_IRON_S12 R/W Yes 0x02 0x30 0x0000 Calibration, soft iron, magnetometer, S12 Table 89 SOFT_IRON_S13 R/W Yes 0x02 0x32 0x0000 Calibration, soft iron, magnetometer, S13 Table 90 SOFT_IRON_S21 R/W Yes 0x02 0x34 0x0000 Calibration, soft iron, magnetometer, S21 Table 91 SOFT_IRON_S22 R/W Yes 0x02 0x36 0x0000 Calibration, soft iron, magnetometer, S22 Table 92 SOFT_IRON_S23 R/W Yes 0x02 0x38 0x0000 Calibration, soft iron, magnetometer, S23 Table 93

SOFT_IRON_S32 R/W Yes 0x02 0x3C 0x0000 Calibration, soft iron, magnetometer, S32 Table 95 SOFT_IRON_S33 R/W Yes 0x02 0x3E 0x0000 Calibration, soft iron, magnetometer, S33 Table 96 BR_BIAS_LOW R/W Yes 0x02 0x40 0x0000 Calibration, offset, barometer, low word Table 99 BR_BIAS_HIGH R/W Ye s 0x02 0x42 0x0000 Calibration, offset, barometer, high word Table 98 Reserved N/A N/A 0x02 0x44 to 0x72 N/A Reserved N/A

USER_SCR_2 R/W Yes 0x02 0x76 0x0000 User Scratch Register 2 Table 121 USER_SCR_3 R/W Yes 0x02 0x78 0x0000 User Scratch Register 3 Table 122 USER_SCR_4 R/W Yes 0x02 0x7A 0x0000 User Scratch Register 4 Table 123 FLSHCNT_LOW R Yes 0x02 0x7C N/A Diagnostic, flash memory count, low word Table 115 FLSHCNT_HIGH R Yes 0x02 0x7E N/A Diagnostic, flash memory count, high word Table 116 PAGE_ID R/W No 0x03 0x00 0x0000 Page identifier N/A GLOB_CMD W No 0x03 0x02 N/A Control, global commands Table 114 Reserved N/A N/A 0x03 0x04 N/A Reserved N/A FNCTIO_CTRL R/W Yes 0x03 0x06 0x000D Control, I/O pins, functional definitions Table 117 GPIO_CTRL R/W Yes 0x03 0x08 0x00X01 Control, I/O pins, general purpose Table 118

DEC_RATE R/W Ye s 0x03 0x0C 0x0000 Control, output sample rate decimation Table 55 NULL_CNFG R/W Yes 0x03 0x0E 0x070A Control, automatic bias correction configuration Table 70 SLP_CNT R/W No 0x03 0x10 N/A Control, power-down/sleep mode Table 119 Reserved N/A N/A 0x03 0x12 to 0x14 N/A Reserved N/A FILTR_BNK_0 R/W Ye s 0x03 0x16 0x0000 Filter selection Table 57 FILTR_BNK_1 R/W Ye s 0x03 0x18 0x0000 Filter selection Table 58 Reserved N/A N/A 0x03 0x1A to 0x1E N/A Reserved N/A ALM_CNFG_0 R/W Yes 0x03 0x20 0x0000 Alarm configuration Table 110 ALM_CNFG_1 R/W Yes 0x03 0x22 0x0000 Alarm configuration Table 111 ALM_CNFG_2 R/W Yes 0x03 0x24 0x0000 Alarm configuration Table 112

XG_ALM_MAGN R/W Ye s 0x03 0x28 0x0000 Alarm, x-axis gyroscope threshold setting Table 100 YG_ALM_MAGN R/W Yes 0x03 0x2A 0x0000 Alarm, y-axis gyroscope threshold setting Table 101 ZG_ALM_MAGN

R/W Yes 0x03 0x2C 0x0000 Alarm, z-axis gyroscope threshold setting Table 102

Rev. B | Page 12 of 36

Page 13

Data Sheet ADIS16488

Name

R/W

Flash

PAGE_ID

Address

Default

Format

FIRM_Y

Yes

0x03

0x7C

N/A

Firmware programming date: year

Table 52

FIR_COEF_Dxxx

R/W

Yes

0x0B

0x00 to 0x7E

N/A

FIR Filter Bank D, Coefficients 0 through 59

Table 62

XA_ALM_MAGN R/W Yes 0x03 0x2E 0x0000 Alarm, x-axis accelerometer threshold Table 103 YA_ALM_MAGN R/W Yes 0x03 0x30 0x0000 Alarm, y-axis accelerometer threshold Table 104 ZA_ALM_MAGN R/W Yes 0x03 0x32 0x0000 Alarm, z-axis accelerometer threshold Table 105 XM_ALM_MAGN R/W Yes 0x03 0x34 0x0000 Alarm, x-axis magnetometer threshold Table 106 YM_ALM_MAGN R/W Ye s 0x03 0x36 0x0000 Alarm, y-axis magnetometer threshold Table 107 ZM_ALM_MAGN R/W Yes 0x03 0x38 0x0000 Alarm, z-axis magnetometer threshold Table 108 BR_ALM_MAGN R/W Yes 0x03 0x3A 0x0000 Alarm, barometer threshold setting Table 109 Reserved N/A N/A 0x03 0x3C to 0x76 N/A Reserved N/A FIRM_REV R Yes 0x03 0x78 N/A Firmware revision Table 50 FIRM_DM R Yes 0x03 0x7A N/A Firmware programming date: day/month Table 51

Reserved N/A N/A 0x03 0x7E N/A Reserved N/A Reserved N/A N/A 0x04 0x00 to 0x18 N/A Reserved N/A SERIAL_NUM R Yes 0x04 0x20 N/A Serial number Table 54 Reserved N/A N/A 0x04 0x22 to 0x7F N/A Reserved N/A FIR_COEF_Axxx R/W Yes 0x05 0x00 to 0x7E N/A FIR Filter Bank A, Coefficients 0 through 59 Table 59 FIR_COEF_Axxx R/W Yes 0x06 0x00 to 0x7E N/A FIR Filter Bank A, Coefficients 60 through 119 Table 59 FIR_COEF_Bxxx R/W Yes 0x07 0x00 to 0x7E N/A FIR Filter Bank B, Coefficients 0 through 59 Table 60 FIR_COEF_Bxxx R/W Yes 0x08 0x00 to 0x7E N/A FIR Filter Bank B, Coefficients 60 through 119 Table 60 FIR_COEF_Cxxx R/W Yes 0x09 0x00 to 0x7E N/A FIR Filter Bank C, Coefficients 0 through 59 Table 61 FIR_COEF_Cxxx R/W Yes 0x0A 0x00 to 0x7E N/A FIR Filter Bank C, Coefficients 60 through 119 Table 61

FIR_COEF_Dxxx R/W Yes 0x0C 0x00 to 0x7E N/A FIR Filter Bank D, Coefficients 60 through 119 Table 62

The GPIO_CTRL[7:4] bits reflect the logic levels on the DIOx lines and do not have a default setting.

Rev. B | Page 13 of 36

Page 14

ADIS16488 Data Sheet

10277-016

X-AXIS GYROSCOPE DATA

0 1515 0

X_GYRO_OUT X_GYRO_LOW

PIN 1

PIN 23

Y-AXIS

X-AXIS

Z-AXIS

10277-017

OUTPUT DATA REGISTERS

After the ADIS16488 completes its start-up process, the PAGE_ID register contains 0x0000, which sets Page 0 as the active page for SPI access. Page 0 contains the output data, real-time clock, status, and product identification registers.

INERTIAL SENSOR DATA FORMAT

The gyroscope, accelerometer, delta angle, delta velocity, and barometer output data registers use a 32-bit, twos complement format. Each output uses two registers to support this resolution. Figure 18 provides an example of how each register contributes to each inertial measurement. In this case, X_GYRO_OUT is the most significant word (upper 16 bits), and X_GYRO_LOW is the least significant word (lower 16 bits). In many cases, using the most significant word registers alone provide sufficient resolution for preserving key performance metrics.

Figure 18. Gyroscope Output Format Example, DEC_RATE > 0

The arrows in Figure 19 describe the direction of the motion, which produces a positive output response in each sensor’s output register. The accelerometers respond to both dynamic and static forces associated with acceleration, including gravity. When lying perfectly flat, as shown in Figure 19, the z-axis accelerometer output is 1 g, and the x and y accelerometers are 0 g.

ROTATION RATE (GYROSCOPE)

The registers that use the x_GYRO_OUT format are the primary registers for the gyroscope measurements (see Table 10, Tabl e 11, and Table 12). When processing data from these registers, use a 16-bit, twos complement data format. Ta b le 13 provides x_GYRO_OUT digital coding examples.

Table 10. X_GYRO_OUT (Page 0, Base Address = 0x12)

Bits Description

[15:0]

X-axis gyroscope data; twos complement, ±450°/sec range, 0°/sec = 0x0000, 1 LSB = 0.02°/sec

Table 11. Y_GYRO_OUT (Page 0, Base Address = 0x16)

Bits Description

[15:0]

Y-axis gyroscope data; twos complement, ±450°/sec range, 0°/sec = 0x0000, 1 LSB = 0.02°/sec

Table 12. Z_GYRO_OUT (Page 0, Base Address = 0x1A)

Bits Description

[15:0]

Z-axis gyroscope data; twos complement, ±450°/sec range, 0°/sec = 0x0000, 1 LSB = 0.02°/sec

Table 13. x_GYRO_OUT Data Format Examples

Rotation Rate Decimal Hex Binary

+450°/sec +22,500 0x57E4 0101 0111 1110 0100 +0.04/sec +2 0x0002 0000 0000 0000 0010 +0.02°/sec +1 0x0001 0000 0000 0000 0001 0°/sec 0 0x0000 0000 0000 0000 0000

−0.02°/sec −1 0xFFFF 1111 1111 1111 1111

−0.04°/sec −2 0xFFFE 1111 1111 1111 1110

−450°/sec −22,500 0xA81C 1010 1000 0001 1100

The registers that use the x_GYRO_LOW naming format provide additional resolution for the gyroscope measurements (see Tabl e 14, Tab l e 15, and Tab l e 16). The MSB has a weight of

0.01°/sec, and each subsequent bit has ½ the weight of the previous one.

Table 14. X_GYRO_LOW (Page 0, Base Address = 0x10)

Bits Description

[15:0] X-axis gyroscope data; additional resolution bits

Table 15. Y_GYRO_LOW (Page 0, Base Address = 0x14)

Bits Description

[15:0] Y-axis gyroscope data; additional resolution bits

Table 16. Z_GYRO_LOW (Page 0, Base Address = 0x18)

Bits Description

[15:0] Z-axis gyroscope data; additional resolution bits

Figure 19. Inertial Sensor Direction Reference Diagram

Rev. B | Page 14 of 36

Page 15

Data Sheet ADIS16488

+0.8 mg

0x0001

0000 0000 0000 0001

( )

Snxnx

RATEDEC

Δt

t 1_

;

,1,

=+×

∆

=∆

ωωθ

[15:0]

X-axis delta angle data; twos complement,

−720

−32,768

0x8000

1000 0000 0000 0000

ACCELERATION

The registers that use the x_ACCL_OUT format are the primary registers for the accelerometer measurements (see Ta bl e 17, Tabl e 18, and Tab l e 19). When processing data from these registers, use a 16-bit, twos complement data format. Tab le 20 provides x_ACCL_OUT digital coding examples.

DELTA ANGLES

The delta angle outputs represent an integration of the gyroscope measurements and use the following formula for all three axes (x-axis displayed):

Table 17. X_ACCL_OUT (Page 0, Base Address = 0x1E)

Bits Description

[15:0]

X-axis accelerometer data; twos complement, ±18 g range, 0 g = 0x0000, 1 LSB = 0.8 mg

Table 18. Y_ACCL_OUT (Page 0, Base Address = 0x22)

Bits Description

[15:0]

Y-axis accelerometer data; twos complement, ±18 g range, 0 g = 0x0000, 1 LSB = 0.8 mg

Table 19. Z_ACCL_OUT (Page 0, Base Address = 0x26)

Bits Description

[15:0]

Z-axis accelerometer data; twos complement, ±18 g range, 0 g = 0x0000, 1 LSB = 0.8 mg

Table 20. x_ACCL_OUT Data Format Examples

Acceleration Decimal Hex Binary

+18 g +22,500 0x57E4 0101 0111 1110 0100 +1.6 mg +2 0x0002 0000 0000 0000 0010

0 mg 0 0x0000 0000 0000 0000 0000

−0.8 mg −1 0xFFFF 1111 1111 1111 1111

−1.6 mg −2 0xFFFE 1111 1111 1111 1110

−18 g −22,500 0xA81C 1010 1000 0001 1100

The registers that use the x_ACCL_LOW naming format provide additional resolution for the accelerometer measurements (see Tab l e 21, Ta b le 22, and Tab le 23). The MSB has a weight of 0.4 mg, and each subsequent bit has ½ the weight of the previous one.

Table 21. X_ACCL_LOW (Page 0, Base Address = 0x1C)

Bits Description

[15:0] X-axis accelerometer data; additional resolution bits

Table 22. Y_ACCL_LOW (Page 0, Base Address = 0x20)

Bits Description

[15:0] Y-axis accelerometer data; additional resolution bits

Table 23. Z_ACCL_LOW (Page 0, Base Address = 0x24)

Bits Description

[15:0] Z-axis accelerometer data; additional resolution bits

where:

is the gyroscope, x-axis.

is the time between samples.

Δt

When using the internal sample clock, f

is equal to 2.46 kHz.

When using the external clock option, the time between samples is the time between active edges on the input clock signal, as measured by the internal clock (252 MHz). See Ta b l e 55 for more information on the DEC_RATE register. The registers that use the x_DELTANG_OUT format are the primary registers for the delta angle calculations. When processing data from these registers, use a 16-bit, twos complement data format (see Table 24, Tab l e 25, and Tab l e 26). Tabl e 27 provides x_DELTANG_OUT digital coding examples.

Table 24. X_DELTANG_OUT (Page 0, Base Address = 0x42)

Bits Description

±720° range, 0° = 0x0000, 1 LSB = 720°/215 = ~0.022°

Table 25. Y_DELTANG_OUT (Page 0, Base Address = 0x46)

Bits Description

[15:0]

Y-axis delta angle data; twos complement, ±720° range, 0° = 0x0000, 1 LSB = 720°/2

= ~0.022°

Table 26. Z_DELTANG_OUT (Page 0, Base Address = 0x4A)

Bits Description

[15:0]

Z-axis delta angle data; twos complement, ±720° range, 0° = 0x0000, 1 LSB = 720°/2

= ~0.022°

Table 27. x_DELTANG_OUT Data Format Examples

Angle (°) Decimal Hex Binary

+720 × (215 − 1)/215 +32,767 0x7FFF 0111 1111 1110 1111 +1440/215 +2 0x0002 0000 0000 0000 0010 +720/215 +1 0x0001 0000 0000 0000 0001 0 0 0x0000 0000 0000 0000 0000

−720/215 −1 0xFFFF 1111 1111 1111 1111

−1440/215 −2 0xFFFE 1111 1111 1111 1110

Rev. B | Page 15 of 36

Page 16

ADIS16488 Data Sheet

[15:0]

X-axis delta angle data; additional resolution bits

( )

Snxnx

RATEDEC

Δtaa

t 1_

;

,1,

=+×

∆

=∆

Bits

Description

Velocity (m/sec)

Decimal

Hex

Binary

+400/215

0x0002

0000 0000 0000 0010

Bits

Description

The registers that use the x_DELTANG_LOW format provide additional resolution for the gyroscope measurements (see Tabl e 28, Tab l e 29, and Tabl e 30). The MSB has a weight of ~0.011° (720°/2

), and each subsequent bit carries a weight of

½ of the previous one.

Table 28. X_DELTANG_LOW (Page 0, Base Address = 0x40)

Bits Description

Table 29. Y_DELTANG_LOW (Page 0, Base Address = 0x44)

Bits Description

[15:0] Y-axis delta angle data; additional resolution bits

Table 30. Z_DELTANG_LOW (Page 0, Base Address = 0x48)

Bits Description

[15:0] Z-axis delta angle data; additional resolution bits

DELTA VELOCITY

The delta velocity outputs represent an integration of the accelerometer measurements and use the following formula for all three axes (x-axis displayed):

where:

is the accelerometer, x-axis.

Δt

is the time between samples.

When using the internal sample clock, f When using the external clock option, the time between samples is the time between active edges on the input clock signal, as measured by the internal clock (252 MHz). See Tabl e 55 for more information on the DEC_RATE register. The registers that use the x_DELTVEL_OUT format are the primary registers for the delta velocity calculations. When processing data from these registers, use a 16-bit, twos complement data format (see Tabl e 31, Tab l e 32, and Tab l e 33). Tab le 34 provides x_DELTVEL_OUT digital coding examples.

is equal to 2.46 kHz.

Table 31. X_DELTVEL_OUT (Page 0, Base Address = 0x4E)

Bits Description

[15:0]

X-axis delta velocity data; twos complement, ±200 m/sec range, 0 m/sec = 0x0000

1 LSB = 200 m/sec ÷ (2

– 1) = ~6.104 mm/sec

Table 32. Y_DELTVEL_OUT (Page 0, Base Address = 0x52)

[15:0]

Y-axis delta velocity data; twos complement, ±200 m/sec range, 0 m/sec = 0x0000

1 LSB = 200 m/sec ÷ (2

− 1) = ~6.104 mm/sec

Table 33. Z_DELTVEL_OUT (Page 0, Base Address = 0x56)

Bits Description

[15:0]

Z-axis delta velocity data; twos complement, ±200 m/sec range, 0 m/sec = 0x0000

1 LSB = 200 m/sec ÷ (2

− 1) = ~6.104 mm/sec

Table 34. x_DELTVEL_OUT, Data Format Examples

+160 × (215 − 1)/215 +32,767 0x7FFF 0111 1111 1111 1111

+200/215 +1 0x0001 0000 0000 0000 0001 0 0 0x0000 0000 0000 0000 0000

−200/215 −1 0xFFFF 1111 1111 1111 1111

−400/215 −2 0xFFFE 1111 1111 1111 1110

−160 −32,768 0x8000 1000 0000 0000 0000

The registers that use the x_DELTVEL_LOW naming format provide additional resolution for the gyroscope measurements (see Tabl e 35, Tab l e 36, and Tabl e 37). The MSB has a weight of ~3.052 mm/sec (200 m/sec ÷ 2

), and each subsequent bit

carries a weight of ½ of the previous one.

Table 35. X_DELTVEL_LOW (Page 0, Base Address = 0x4C)

Bits Description

[15:0] X-axis delta velocity data; additional resolution bits

Table 36. Y_DELTVEL_LOW (Page 0, Base Address = 0x50)

[15:0] Y-axis delta velocity data; additional resolution bits

Table 37. Z_DELTVEL_LOW (Page 0, Base Address = 0x54)

Bits Description

[15:0] Z-axis delta velocity data; additional resolution bits

Rev. B | Page 16 of 36

Page 17

Data Sheet ADIS16488

+0.00004

0x0001

0000 0000 0000 0001

[15:0]

Temperature data; twos complement,

MAGNETOMETERS

The registers that use the x_MAGN_OUT format are the primary registers for the magnetometer measurements. When processing data from these registers, use a 16-bit, twos complement data format. Ta b le 38, Ta bl e 39, and Tabl e 40 provide each register’s numerical format, and Tab le 41 provides x_MAGN_OUT digital coding examples.

Table 38. X_MAGN_OUT (Page 0, Base Address = 0x28)

Bits Description

[15:0]

Table 39. Y_MAGN_OUT (Page 0, Base Address = 0x2A)

Bits Description

[15:0]

X-axis magnetometer data; twos complement, ±3.2767 gauss range, 0 gauss = 0x0000, 1 LSB = 0.1 mgauss

Y-axis magnetometer data; twos complement, ±3.2767 gauss range, 0 gauss = 0x0000, 1 LSB = 0.1 mgauss

Table 42. BAROM_OUT (Page 0, Base Address = 0x30)

Bits Description

[15:0]

Barometric pressure; twos complement, ±1.31 bar range, 0 bar = 0x0000, 40 µbar/LSB

Table 43. BAROM_OUT Data Format Examples

Pressure (bar) Decimal Hex Binary

+0.00004 × (215 − 1) +32,767 0x7FFF 0111 1111 1110 1111 +0.00008 +2 0x0002 0000 0000 0000 0010

0 0 0x0000 0000 0000 0000 0000

−0.00004 −1 0xFFFF 1111 1111 1111 1111

−0.00008 −2 0xFFFE 1111 1111 1111 1110

−0.00004 × 215 −32,768 0x8000 1000 0000 0000 0000

The BAROM_LOW register provides additional resolution for the barometric pressure measurement. The MSB has a weight of 20 µbar, and each subsequent bit carries a weight of ½ of the previous one.

Table 40. Z_MAGN_OUT (Page 0, Base Address = 0x2C)

Bits Description

[15:0]

Z-axis magnetometer data; twos complement, ±3.2767 gauss range, 0 gauss = 0x0000, 1 LSB = 0.1 mgauss

Table 41. x_MAGN_OUT Data Format Examples

Magnetic Field Decimal Hex Binary

+3.2767 gauss +32,767 0x7FFF 0111 1111 1111 1111 +0.2 mgauss +2 0x0002 0000 0000 0000 0010 +0.1 mgauss +1 0x0001 0000 0000 0000 0001 0 gauss 0 0x0000 0000 0000 0000 0000

−0.1 mgauss −1 0xFFFF 1111 1111 1111 1111

−0.2 mgauss −2 0xFFFE 1111 1111 1111 1110

−3.2768 gauss −32,768 0x8000 1000 0000 0000 0000

BAROMETER

The BAROM_OUT register (see Table 42) and BAROM_LOW register (see Tab l e 44) provide access to the barometric pressure data. These two registers combine to provide a 32-bit, twos complement format. Some applications are able to use BAROM_OUT by itself. For cases where the finer resolution available from BAROM_LOW is valuable, combine them in the same manner as the gyroscopes (see Figure 18). When processing data from the BAROM_OUT register alone, use a 16-bit, twos complement data format. Tab le 42 provides the numerical format in BAROM_OUT, and Table 43 provides digital coding examples.

Table 44. BAROM_LOW (Page 0, Base Address = 0x2E)

Bits Description

[15:0] Barometric pressure; additional resolution bits

INTERNAL TEMPERATURE

The TEMP_OUT register provides an internal temperature measurement that can be useful for observing relative temperature changes inside of the ADIS16488 (see Ta b le 45). Tab l e 46 provides TEMP_OUT digital coding examples. Note that this temperature reflects a higher temperature than ambient, due to self-heating.

Table 45. TEMP_OUT (Page 0, Base Address = 0x0E)

Bits Description

0.00565°C per LSB, 25°C = 0x0000

Table 46. TEMP_OUT Data Format Examples

Temperature (°C) Decimal Hex Binary

+85 +10,619 0x297B 0010 1001 0111 1011 +25 + 0.0113 +2 0x0002 0000 0000 0000 0010 +25 + 0.00565 +1 0x0001 0000 0000 0000 0001 +25 0 0x0000 0000 0000 0000 0000 +25 − 0.00565 −1 0xFFFF 1111 1111 1111 1111 +25 − 0.0113 −2 0xFFFE 1111 1111 1111 1110

−40 −11,504 0xD310 1101 0011 0001 0000

Rev. B | Page 17 of 36

Page 18

ADIS16488 Data Sheet

[2:1]

Not used

Self-test failure, Y-axis magnetometer (1 = failure)

Y-axis accelerometer alarm flag (1 = alarm is active)

STATUS/ALARM INDICATORS

The SYS_E_FLAG register in Tabl e 47 provides the system error flags and new data bits for the magnetometer and barometer outputs. The new data flags are useful for triggering data collection of the magnetometer and barometer (x_MAGN_OUT and BARO_xxx registers) because they update at a fixed rate that is not dependent on the DEC_RATE setting. Note that reading SYS_E_FLAG also resets it to 0x0000.

Table 47. SYS_E_FLAG (Page 0, Base Address = 0x08)

Bits Description (Default = 0x0000)

[15] Watch dog timer flag (1 = timed out) [14:10] Not used 9 New data flag, barometer (1 = new, unread data)1 8 New data flag, magnetometer (1 = new, unread data)2 7 Processing overrun (1 = error) 6 Flash memory update, result of GLOB_CMD[3] = 1

(1 = failed update, 0 = update successful) 5 Inertial self-test failure (1 = DIAG_STS ≠ 0x0000) 4 Sensor overrange (1 = at least one sensor overranged) 3 SPI communication error

(1 = error condition, when the number of SCLK pulses

is not equal to a multiple of 16)

The ALM_STS register in Table 49 provides the alarm bits for the programmable alarm levels of each sensor. Note that reading ALM_STS also resets it to 0x0000.

Table 49. ALM_STS (Page 0, Base Address = 0x0C)

Bits Description (Default = 0x0000)

[15:12] Not used 11 Barometer alarm flag (1 = alarm is active) 10 Z-axis magnetometer alarm flag (1 = alarm is active) 9 Y-axis magnetometer alarm flag (1 = alarm is active) 8 X-axis magnetometer alarm flag (1 = alarm is active) [7:6] Not used 5 Z-axis accelerometer alarm flag (1 = alarm is active)

3 X-axis accelerometer alarm flag (1 = alarm is active) 2 Z-axis gyroscope alarm flag (1 = alarm is active) 1 Y-axis gyroscope alarm flag (1 = alarm is active) 0 X-axis gyroscope alarm flag (1 = alarm is active)

0 Alarm status flag (1 = ALM_STS ≠ 0x0000)

This flag restores to zero after reading the contents on BAROM_OUT.

This flag restores to zero after reading one x_MAGN_OUT register.

The DIAG_STS register in Tab l e 48 provides the flags for the internal self-test function, which is from GLOB_CMD[1] (see Tabl e 114). Note that the barometer’s flag, DIAG_STS[11], only updates after start-up and reset operations. Note that reading DIAG_STS also resets it to 0x0000.

Table 48. DIAG_STS (Page 0, Base Address = 0x0A)

Bits Description (Default = 0x0000)

[15:12] Not used 11 Self-test failure, barometer (1 = failed at start-up) 10 Self-test failure, Z-axis magnetometer (1 = failure)

8 Self-test failure, X-axis magnetometer (1 = failure) [7:6] Not used 5 Self-test failure, Z-axis accelerometer (1 = failure) 4 Self-test failure, Y-axis accelerometer (1 = failure) 3 Self-test failure, X-axis accelerometer (1 = failure) 2 Self-test failure, Z-axis gyroscope (1 = failure) 1 Self-test failure, Y-axis gyroscope (1 = failure) 0 Self-test failure, X-axis gyroscope (1 = failure)

Rev. B | Page 18 of 36

Page 19

Data Sheet ADIS16488

[3:0]

Binary, revision, hundredths digit

FIRMWARE REVISION

The FIRM_REV register (see Tabl e 50) provides the firmware revision for the internal processor. Each nibble represents a digit in this revision code. For example, if FIRM_REV = 0x0102, the firmware revision is 1.02.

Table 50. FIRM_REV (Page 3, Base Address = 0x78)

Bits Description

[15:12] Binary, revision, 10’s digit [11:8] Binary, revision, 1’s digit [7:4] Binary, revision, tenths digit

The FIRM_DM register (see Tabl e 51) contains the month and day of the factory configuration date. FIRM_DM[15:12] and FIRM_DM[11:8] contain digits that represent the month of factory configuration. For example, November is the 11 month in a year and represented by FIRM_DM[15:8] = 0x11. FIRM_DM[7:4] and FIRM_DM[3:0] contain digits that represent the day of factory configuration. For example, the 27 the month is represented by FIRM_DM[7:0] = 0x27.

Table 51. FIRM_DM (Page 3, Base Address = 0x7A)

Bits Description

[15:12] Binary, month 10’s digit, range: 0 to 1 [11:8] Binary, month 1’s digit, range: 0 to 9 [7:4] Binary, day 10’s digit, range: 0 to 3 [3:0] Binary, day 1’s digit, range: 0 to 9

day of

The FIRM_Y register (see Tab l e 52) contains the year of the factory configuration date. For example, the year of 2013 is represented by FIRM_Y = 0x2013.

Table 52. FIRM_Y (Page 3, Base Address = 0x7C)

Bits Description

[15:12] Binary, year 1000’s digit, range: 0 to 9 [11:8] Binary, year 100’s digit, range: 0 to 9 [7:4] Binary, year 10’s digit, range: 0 to 9 [3:0] Binary, year 1’s digit, range: 0 to 9

PRODUCT IDENTIFICATION

The PROD_ID register (see Tabl e 53) contains the binary equivalent of the part number (16,488 = 0x4068), and the SERIAL_NUM register (see Tab le 54) contains a lot-specific serial number.

Table 53. PROD_ID (Page 0, Base Address = 0x7E)

Bits Description (Default = 0x4068)

[15:0] Product identification = 0x4068

Table 54. SERIAL_NUM (Page 4, Base Address = 0x20)

Bits Description

[15:0] Lot-specific serial number

Rev. B | Page 19 of 36

Page 20

ADIS16488 Data Sheet

[15:11]

Don’t care

MEMS

SENSOR

330Hz

÷4

2.46kHz, f

GYROSCOPE 2-POLE: 404Hz , 757Hz

ACCELEROMETER 1-POLE: 330Hz

4×

AVERAGE

DECIMATION

FILTER

SELECTABLE

FIR FILT E R BANK

FILTR_BNK_0 FILTR_BNK_1

AVERAGE/DECIMATION FILTER

D = DEC_RATE[10:0] + 1

1 4

÷D

FIR

FILTER

BANK

10277-018

INTERNAL

CLOCK

9.84kHz

DIOx

OPTIONAL INPUT CLOCK

FNCTIO _CTRL[7] = 1

< 2400Hz

NOTES

1. WHEN FNCTIO_CTRL [ 7] = 1, EACH CLOCK PULSE ON THE DE S IGNATED DIOx LINE (FNCTIO_CTRL[5:4]) STARTS A 4-SAMPLE BURST, AT A SAMPLE RATE OF 9.84kHz. THESE FOUR SAMPLES FEED INTO T HE 4x AVERAGE/DECIMATION FILTER, W HICH PRODUCES A

DATA RATE THAT IS EQUAL TO THE INPUT CLOCK FREQUENCY.

DIGITAL SIGNAL PROCESSING

GYROSCOPES/ACCELEROMETERS

Figure 20 provides a signal flow diagram for all of the components and settings that influence the frequency response for the accelerometers and gyroscopes. The sample rate for each accelerometer and gyroscope is 9.84 kHz. Each sensor has its own averaging/decimation filter stage, which reduces the update rate to 2.46 kSPS. When using the external clock option (FNCTIO_CTRL[7:4], see Tabl e 117), the input clock drives a 4-sample burst at a sample rate of 9.84kSPS, which feeds into the 4x averaging/decimation filter. This results in a data rate that is equal to the input clock frequency.

AVERAGING/DECIMATION FILTER

The DEC_RATE register (see Ta b le 55) provides user control for the final filter stage (see Figure 20), which averages and decimates the accelerometers, gyroscopes, delta angle, and delta velocity data. The output sample rate is equal to 2460/(DEC_RATE + 1). When using the external clock option (FNCTIO_CTRL[7:4], see Ta b le

117), replace the “2460” number in this relationship, with the input clock frequency. For example, turn to Page 3 (DIN = 0x8003), and set DEC_RATE = 0x18 (DIN = 0x8C18, then DIN = 0x8D00) to reduce the output sample rate to 98.4 SPS (2460 ÷ 25).

Table 55. DEC_RATE (Page 3, Base Address = 0x0C)

Bits Description (Default = 0x0000)

[15:11] Don’t care [10:0]

Decimation rate, binary format, maximum = 2047 See Figure 20 for impact on sample rate

MAGNETOMETER/BAROMETER

When using the internal sampling clock, the magnetometer output registers (xMAGN_OUT) update at a rate of 102.5 SPS and the barometer output registers (BARO_xxx) update at a rate of 51.25 SPS. When using the external clock, the magnetometers update at a rate of 1/24th of the input clock frequency and the barometers update at a rate that is 1/48th of the input clock frequenc y. The update rates for the magnetometer and barometers do not change with the DEC_RATE register settings. SYS_E_FLAG[9:8] (see Tab le 47) offers new data bits for these registers and the SEQ_CNT register provides a counter function to help determine when there is new data in the magnetometer and barometer registers. When SEQ_CNT = 0x0001, there is new data in the magnetometer and barometer output registers. The SEQ_CNT register can be useful during initialization to help synchronize read loops for new data in both magnetometer and barometer outputs. When beginning a continuous read loop, read SEQ_CNT, then subtract this value from the maximum value shown (range) in Tabl e 56 to calculate the number of internal sample cycles until both magnetometer and barometer data is ne w.

Table 56. SEQ_CNT (Page 0, Base Address = 0x06)

Bits Description

[6:0] Binary counter: range = 1 to 48/(DEC_RATE + 1)

Figure 20. Sampling and Frequency Response Block Diagram

Rev. B | Page 20 of 36

Page 21

Data Sheet ADIS16488

[7:6] 8

0x08

0x02 to 0x07

Not used

0x08

0x7E

FIR_COEF_B119

0x09

0x00

PAGE_ID

0x0A

0x0C to 0x7C

FIR FILTER BANKS

The ADIS16488 provides four configurable, 120-tap FIR filter banks. Each coefficient is 16 bits wide and occupies its own register location with each page. When designing a FIR filter for these banks, use a sample rate of 2.46 kHz and scale the coefficients so that their sum equals 32,768. For filter designs that have less than 120 taps, load the coefficients into the lower portion of the filter and start with Coefficient 1. Make sure that all unused taps are equal to zero, so that they do not add phase delay to the response. The FILTR_BNK_x registers provide three bits per sensor, which configure the filter bank (A, B, C, D) and turn filtering on and off. For example, turn to Page 3 (DIN = 0x8003), then write 0x0057 to FILTR_BNK_0 (DIN = 0x9657, DIN = 0x9700) to set the x-axis gyroscope to use the FIR filter in Bank D, to set the y-axis gyroscope to use the FIR filter in Bank B, and to enable these FIR filters in both x- and y-axis gyroscopes. Note that the filter settings update after writing to the upper byte; therefore, always configure the lower byte first. In cases that require configuration to only the lower byte of either FILTR_BNK_0 or FILTR_BNK_1, complete the process by writing 0x00 to the upper byte.

Table 57. FILTR_BNK_0 (Page 3, Base Address = 0x16)

Bits Description (Default = 0x0000)

15 Don’t care 14 Y-axis accelerometer filter enable (1 = enabled) [13:12]

11 X-axis accelerometer filter enable (1 = enabled) [10:9]

8 Z-axis gyroscope filter enable (1 = enabled)

5 Y-axis gyroscope filter enable (1 = enabled) [4:3]

2 X-axis gyroscope filter enable (1 = enabled) [1:0]

Table 58. FILTR_BNK_1 (Page 3, Base Address = 0x18)

Bits Description (Default = 0x0000)

[15:12] Don’t care 11 Z-axis magnetometer filter enable (1 = enabled) [10:9]

8 Y-axis magnetometer filter enable (1 = enabled) [7:6]

5 X-axis magnetometer filter enable (1 = enabled) [4:3]

2 Z-axis accelerometer filter enable (1 = enabled) [1:0]

Y-axis accelerometer filter bank selection: 00 = Bank A, 01 = Bank B, 10 = Bank C, 11 = Bank D

X-axis accelerometer filter bank selection: 00 = Bank A, 01 = Bank B, 10 = Bank C, 11 = Bank D

Z-axis gyroscope filter bank selection: 00 = Bank A, 01 = Bank B, 10 = Bank C, 11 = Bank D

Y-axis gyroscope filter bank selection: 00 = Bank A, 01 = Bank B, 10 = Bank C, 11 = Bank D

X-axis gyroscope filter bank selection: 00 = Bank A, 01 = Bank B, 10 = Bank C, 11 = Bank D

Z-axis magnetometer filter bank selection: 00 = Bank A, 01 = Bank B, 10 = Bank C, 11 = Bank D

Y-axis magnetometer filter bank selection: 00 = Bank A, 01 = Bank B, 10 = Bank C, 11 = Bank D

X-axis magnetometer filter bank selection: 00 = Bank A, 01 = Bank B, 10 = Bank C, 11 = Bank D

Z-axis accelerometer filter bank selection: 00 = Bank A, 01 = Bank B, 10 = Bank C, 11 = Bank D

Rev. B | Page 21 of 36

Filter Memory Organization

Each filter bank uses two pages of the user register structure. See Tab l e 59, Ta b l e 60, Tab l e 61, and Ta b le 62 for the register addresses in each filter bank.

Table 59. Filter Bank A Memory Map

Page PAGE _ID Address Register

5 0x05 0x00 PAGE_ID 5 0x05 0x02 to 0x07 Not used 5 0x05 0x08 FIR_COEF_A000 5 0x05 0x0A FIR_COEF_A001 5 0x05 0x0C to 0x7C

5 0x05 0x7E FIR_COEF_A059 6 0x06 0x00 PAGE_ID 6 0x06 0x02 to 0x07 Not used 6 0x06 0x08 FIR_COEF_A060 6 0x06 0x0A FIR_COEF_A061 6 0x06 0x0C to 0x7C

6 0x06 0x7E FIR_COEF_D119

FIR_COEF_A002 to FIR_COEF_A058

FIR_COEF_A062 to FIR_COEF_A118

Table 60. Filter Bank B Memory Map

Page PAGE _ID Address Register

7 0x07 0x00 PAGE_ID 7 0x07 0x02 to 0x07 Not used 7 0x07 0x08 FIR_COEF_B000 7 0x07 0x0A FIR_COEF_B001 7 0x07 0x0C to 0x7C

7 0x07 0x7E FIR_COEF_B059 8 0x08 0x00 PAGE_ID

8 0x08 0x08 FIR_COEF_B060 8 0x08 0x0A FIR_COEF_B061 8 0x08 0x0C to 0x7C

FIR_COEF_B002 to FIR_COEF_B058

FIR_COEF_B062 to FIR_COEF_B118

Table 61. Filter Bank C Memory Map

Page PAGE _ID Address Register

9 0x09 0x02 to 0x07 Not used 9 0x09 0x08 FIR_COEF_C000 9 0x09 0x0A FIR_COEF_C001 9 0x09 0x0C to 0x7C

9 0x09 0x7E FIR_COEF_C059 10 0x0A 0x00 PAGE_ID 10 0x0A 0x02 to 0x07 Not used 10 0x0A 0x08 FIR_COEF_C060 10 0x0A 0x0A FIR_COEF_C061

10 0x0A 0x7E FIR_COEF_C119

FIR_COEF_C002 to FIR_COEF_C058

FIR_COEF_C062 to FIR_COEF_C118

Page 22

ADIS16488 Data Sheet

0x0C

0x08

FIR_COEF_D060

NO FIR

FILTERING

0 –10 –20

MAGNITUDE ( dB)

–30 –40 –50 –60 –70 –80 –90

–100

0 200 400 600 800 1000 1200

FREQUENCY (Hz)

10277-019

AD CB

Table 62. Filter Bank D Memory Map

Page PAGE _ID Address Register

11 0x0B 0x00 PAGE_ID 11 0x0B 0x02 to 0x07 Not used 11 0x0B 0x08 FIR_COEF_D000 11 0x0B 0x0A FIR_COEF_D001 11 0x0B 0x0C to 0x7C

FIR_COEF_D002 to

FIR_COEF_D058 11 0x0B 0x7E FIR_COEF_D059 12 0x0C 0x00 PAGE_ID 12 0x0C 0x02 to 0x07 Not used

12 0x0C 0x0A FIR_COEF_D061 12 0x0C 0x0C to 0x7C

FIR_COEF_D062 to

FIR_COEF_D118 12 0x0C 0x7E FIR_COEF_D119

Default Filter Performance

The FIR filter banks have factory-programmed filter designs. They are all low-pass filters that have unity dc gain. Tab le 63 provides a summary of each filter design, and Figure 21 shows the frequency response characteristics. The phase delay is equal to ½ of the total number of taps.

Table 63. FIR Filter Descriptions, Default Configuration

FIR Filter Bank Taps −3 dB Frequency (Hz)

A 120 310 B 120 55 C 32 275 D 32 63

Figure 21. FIR Filter Frequency Response Curves

Rev. B | Page 22 of 36

Page 23

Data Sheet ADIS16488

X-AXIS

GYRO

FACT

ORY

CALIBRATION

AND

FILTERING

X_GYRO_OUT X_GYRO_LOW

XG_BIAS_HIGH

XG_BIAS_LOW

1 + X_GYRO_SCALE

10277-020

[15:0]

Bits

Description (Default = 0x0000)

[7:4]

Not used

[15:0]

X-axis gyroscope scale correction; twos complement,

CALIBRATION

The ADIS16488 factory calibration produces correction formulas for the gyroscopes, accelerometers, magnetometers, and barometers, and then programs them into the flash memory. In addition, there are a series of user-configurable calibration registers, for in-system tuning.

GYROSCOPES

The user-calibration for the gyroscopes includes registers for adjusting bias and sensitivity, as shown in Figure 22.

Figure 22. User Calibration Signal Path, Gyroscopes

Manual Bias Correction

The xG_BIAS_HIGH registers (see Tabl e 64, Tab l e 65, and Tabl e 66) and xG_BIAS_LOW registers (see Tab l e 67, Tab l e 68, and Table 69) provide a bias adjustment function for the output of each gyroscope sensor.

Table 64. XG_BIAS_HIGH (Page 2, Base Address = 0x12)

Bits Description (Default = 0x0000)

[15:0]

Table 65. YG_BIAS_HIGH (Page 2, Base Address = 0x16)

Bits Description (Default = 0x0000)

[15:0]

Table 66. ZG_BIAS_HIGH (Page 2, Base Address = 0x1A)

Bits Description (Default = 0x0000)

Table 67. XG_BIAS_LOW (Page 2, Base Address = 0x10)

Bits Description (Default = 0x0000)

[15:0]

Table 68. YG_BIAS_LOW (Page 2, Base Address = 0x14)

[15:0]

Table 69. ZG_BIAS_LOW (Page 2, Base Address = 0x18)

Bits Description (Default = 0x0000)

[15:0]

X-axis gyroscope offset correction, upper word twos complement, 0°/sec = 0x0000, 1 LSB = 0.02°/sec

Y-axis gyroscope offset correction, upper word; twos complement, 0°/sec = 0x0000, 1 LSB = 0.02°/sec

Z-axis gyroscope offset correction, upper word; twos complement, 0°/sec = 0x0000, 1 LSB = 0.02°/sec

X-axis gyroscope offset correction, lower word; twos complement, 0°/sec = 0x0000, 1 LSB = 0.02°/sec ÷ 2

= ~0.000000305°/sec

Y-axis gyroscope offset correction, lower word; twos complement, 0°/sec = 0x0000, 1 LSB = 0.02°/sec ÷ 2

= ~0.000000305°/sec

Z-axis gyroscope offset correction, lower word twos complement, 0°/sec = 0x0000, 1 LSB = 0.02°/sec ÷ 2

= ~0.000000305°/sec

Bias Null Command

The continuous bias estimator (CBE) accumulates and averages data in a 64-sample FIFO. The average time (t

)

for the bias estimates relies on the sample time base setting in NULL_CNFG[3:0] (see Tab le 70). Users can load the correction factors of the CBE into the gyroscope offset correction registers (see Tab l e 64, Table 65, Tab l e 66, Tabl e 67, Tabl e 68, and Table 69) using the bias null command in GLOB_CMD[0] (see Tabl e 114). NULL_CNFG[13:8] provide on/off controls for the sensors that update when issuing a bias null command. The factory default configuration for NULL_CNFG enables the bias null command for the gyroscopes, disables the bias null command for the accelerometers, and establishes the average time to ~26.64 seconds.

Table 70. NULL_CNFG (Page 3, Base Address = 0x0E)

Bits Description (Default = 0x070A)

[15:14] Not used 13 Z-axis acceleration bias correction enable (1 = enabled) 12 Y-axis acceleration bias correction enable (1 = enabled) 11 X-axis acceleration bias correction enable (1 = enabled) 10 Z-axis gyroscope bias correction enable (1 = enabled) 9 Y-axis gyroscope bias correction enable (1 = enabled) 8 X-axis gyroscope bias correction enable (1 = enabled)

[3:0]

Time base control (TBC), range: 0 to 13 (default = 10);

TBC

= 2

/2460, time base,

= 64 × tB, average time

Turn to Page 3 (DIN = 0x8003) and set GLOB_CMD[0] = 1 (DIN = 0x8201, then DIN = 0x8300) to update the user offset registers with the correction factors of the CBE. Make sure that the inertial platform is stable during the entire average time for optimal bias estimates.

Manual Sensitivity Correction

The x_GYRO_SCALE registers enable sensitivity adjustment (see Tab l e 71, Table 72, and Tabl e 73).

Table 71. X_GYRO_SCALE (Page 2, Base Address = 0x04)

Bits Description (Default = 0x0000)

0x0000 = unity gain, 1 LSB = 1 ÷ 215 = ~0.0003052%

Table 72. Y_GYRO_SCALE (Page 2, Base Address = 0x06)

Bits Description (Default = 0x0000)

[15:0]

Y-axis gyroscope scale correction; twos complement, 0x0000 = unity gain, 1 LSB = 1 ÷ 215 = ~0.0003052%

Table 73. Z_GYRO_SCALE (Page 2, Base Address = 0x08)

Bits Description (Default = 0x0000)

[15:0]

Rev. B | Page 23 of 36

Z-axis gyroscope scale correction; twos complement, 0x0000 = unity gain, 1 LSB = 1 ÷ 2

= ~0.0003052%

Page 24

ADIS16488 Data Sheet

[5:2]

Not used

X-AXIS

ACCL

FAC

TORY

CALIBRATION

AND

FILTERING

X_ACCL_OUT X_ACCL_LOW

XA_BIAS_HIGH XA_BIAS_LOW

1 + X_ACCL_SCALE

10277-021

[15:0]

Bits

Description (Default = 0x0000)

[15:0]

Y-axis accelerometer scale correction,

Linear Acceleration on Effect on Gyroscope Bias

MEMS gyroscopes typically have a bias response to linear acceleration that is normal to their axis of rotation. The ADIS16488 offers an optional compensation function for this effect. Turn to Page 3 (DIN = 0x8003) and set CONFIG[7] = 1 (DIN = 0x9080, DIN = 0x9100).

Table 78. XA_BIAS_LOW (Page 2, Base Address = 0x1C)

Bits Description (Default = 0x0000)

[15:0]

X-axis accelerometer offset correction, low word, Twos complement, 0 g = 0x0000, 1 LSB = 0.8 mg ÷ 2

= ~0.0000122 mg

Table 79. YA_BIAS_LOW (Page 2, Base Address = 0x20)

Table 74. CONFIG (Page 3, Base Address = 0x0A)

Bits Description (Default = 0x00C0)

[15:8] Not used 7 Linear-g compensation for gyroscopes (1 = enabled) 6 Point of percussion alignment (1 = enabled)

Real-time clock, daylight savings time (1: enabled, 0: disabled)

Real-time clock control (1: relative/elapsed timer mode, 0: calendar mode)

ACCELEROMETERS

The user-calibration for the accelerometers includes registers for adjusting bias and sensitivity, as shown in Figure 23.

Figure 23. User Calibration Signal Path, Gyroscopes

Manual Bias Correction

The xA_BIAS_HIGH (see Tab l e 75, Tab l e 76, and Ta bl e 77) and xA_BIAS_LOW (see Tab l e 78, Tab l e 79, and Tabl e 80) registers provide a bias adjustment function for the output of each gyroscope sensor. The xA_BIAS_HIGH registers use the same format as x_ACCL_OUT registers. The xA_BIAS_LOW registers use the same format as x_ACCL_LOW registers.

[15:0]

Y-axis accelerometer offset correction, low word, Twos complement, 0 g = 0x0000, 1 LSB = 0.8 mg ÷ 2

= ~0.0000122 mg

Table 80. ZA_BIAS_LOW (Page 2, Base Address = 0x24)

Bits Description (Default = 0x0000)

[15:0]

Z-axis accelerometer offset correction, low word;, Twos complement, 0 g = 0x0000, 1 LSB = 0.8 mg ÷ 2

= ~0.0000122 mg

Manual Sensitivity Correction

The x_ACCL_SCALE registers enable sensitivity adjustment (see Tab l e 81, Table 82, Ta bl e 83).

Table 81. X_ACCL_SCALE (Page 2, Base Address = 0x0A)

Bits Description (Default = 0x0000)

[15:0]

X-axis accelerometer scale correction, Twos complement, 0x0000 = unity gain, 1 LSB = 1 ÷ 2

= ~0.0003052%

Table 82. Y_ACCL_SCALE (Page 2, Base Address = 0x0C)

Bits Description (Default = 0x0000)

Twos complement, 0x0000 = unity gain, 1 LSB = 1 ÷ 2

= ~0.0003052%

Table 83. Z_ACCL_SCALE (Page 2, Base Address = 0x0E)

Bits Description (Default = 0x0000)

[15:0]

Z-axis accelerometer scale correction, Twos complement, 0x0000 = unity gain, 1 LSB = 1 ÷ 2

= ~0.0003052%

Table 75. XA_BIAS_HIGH (Page 2, Base Address = 0x1E)

Bits Description (Default = 0x0000)

X-axis accelerometer offset correction, high word, Twos complement, 0 g = 0x0000, 1 LSB = 0.8 mg

Table 76. YA_BIAS_HIGH (Page 2, Base Address = 0x22)

Bits Description (Default = 0x0000)

[15:0]

Y-axis accelerometer offset correction, high word, Twos complement, 0 g = 0x0000, 1 LSB = 0.8 mg

Table 77. ZA_BIAS_HIGH (Page 2, Base Address = 0x26)

Bits Description (Default = 0x0000)

[15:0]

Z-axis accelerometer offset correction, high word, Twos complement, 0 g = 0x0000, 1 LSB = 0.8 mg

Rev. B | Page 24 of 36

MAGNETOMETERS

The user calibration registers enable both hard-iron and softiron correction, as shown in the following relationship:























, MY, and MZ variables represent the magnetometer

The M



 



3231

data, prior to application of the user correction formula. The M

, MYC, and MZC represent the magnetometer data, after the

application of the user correction formula.





1312



























  















Page 25

Data Sheet ADIS16488

−3.2768 gauss

−32,768

0x8000

1000 0000 0000 0000

[15:0]

Magnetometer soft-iron correction factor, S21 +200/215

0x0002

0000 0000 0000 0010

Hard-Iron Correction

Tabl e 84, Tab l e 85, and Tab le 86 describe the register format for the hard-iron correction factors: H

, HY, and HZ. These

registers use a twos complement format. Table 87 provides some numerical examples for converting the digital codes for these registers into their decimal equivalent.

Table 84. HARD_IRON_X (Page 2, Base Address = 0x28)

Bits Description (Default = 0x0000)

[15:0] X-axis magnetometer hard-iron correction factor, HX

Twos complement, ±3.2767 gauss range,

0.1 mgauss/LSB, 0 gauss = 0x0000 (see Table 87)

Table 89. SOFT_IRON_S12 (Page 2, Base Address = 0x30)

Bits Description (Default = 0x0000)

[15:0] Magnetometer soft-iron correction factor, S12

Twos complement format, see Table 97 for examples

Table 90. SOFT_IRON_S13 (Page 2, Base Address = 0x32)

Bits Description (Default = 0x0000)

[15:0] Magnetometer soft-iron correction factor, S13

Twos complement format, see Table 97 for examples

Table 91. SOFT_IRON_S21 (Page 2, Base Address = 0x34)

Bits Description (Default = 0x0000)

Table 85. HARD_IRON_Y (Page 2, Base Address = 0x2A)

Bits Description (Default = 0x0000)

[15:0] Y-axis magnetometer hard-iron correction factor, HY

Twos complement, ±3.2767 gauss range,

0.1 mgauss/LSB, 0 gauss = 0x0000 (see Table 87)

Table 86. HARD_IRON_Z (Page 2, Base Address = 0x2C)

Bits Description (Default = 0x0000)

[15:0] Z-axis magnetometer hard-iron correction factor, Hz

Twos complement, ±3.2767 gauss range,

0.1 mgauss/LSB, 0 gauss = 0x0000 (see Table 87)

Table 87. x_MAGN_OUT Data Format Examples

Magnetic Field Decimal Hex Binary

+3.2767 gauss +32,767 0x7FFF 0111 1111 1111 1111 +0.2 mgauss +2 0x0002 0000 0000 0000 0010 +0.1 mgauss +1 0x0001 0000 0000 0000 0001 0 gauss 0 0x0000 0000 0000 0000 0000

−0.1 mgauss −1 0xFFFF 1111 1111 1111 1111

−0.2 mgauss −2 0xFFFE 1111 1111 1111 1110

Soft-Iron Correction Matrix

The soft-iron correction matrix contains correction factors for both sensitivity (S S

). The registers that represent each soft-iron correction factor

are in Ta b le 88 (S Tabl e 92 (S Tabl e 96 (S

, S22, S33) and alignment (S12, S13, S21, S23, S31,

), Tabl e 89 (S12), Tabl e 90 (S13), Tabl e 91 (S21),

), Table 93 (S23), Tabl e 94 (S31), Table 95 (S32), and

). Table 97 offers some numerical examples for converting between the digital codes and their effect on the magnetometer output, in terms of percent-change.

Table 88. SOFT_IRON_S11 (Page 2, Base Address = 0x2E)

Bits Description (Default = 0x0000)

[15:0] Magnetometer soft-iron correction factor, S11

Twos complement format, see Ta ble 97 for examples

Table 92. SOFT_IRON_S22 (Page 2, Base Address = 0x36)

Bits Description (Default = 0x0000)

[15:0] Magnetometer soft-iron correction factor, S22

Twos complement format, see Ta ble 97 for examples

Table 93. SOFT_IRON_S23 (Page 2, Base Address = 0x38)

Bits Description (Default = 0x0000)

[15:0] Magnetometer soft-iron correction factor, S23

Twos complement format, see Ta ble 97 for examples

Table 94. SOFT_IRON_S31 (Page 2, Base Address = 0x3A)

Bits Description (Default = 0x0000)

[15:0] Magnetometer soft-iron correction factor, S31

Twos complement format, see Ta ble 97 for examples

Table 95. SOFT_IRON_S32 (Page 2, Base Address = 0x3C)

Bits Description (Default = 0x0000)

[15:0] Magnetometer soft-iron correction factor, S32

Twos complement format, see Ta ble 97 for examples

Table 96. SOFT_IRON_S33 (Page 2, Base Address = 0x3E)

Bits Description (Default = 0x0000)

[15:0] Magnetometer soft-iron correction factor, S33

Twos complement format, see Ta ble 97 for examples

Table 97. Soft Iron Correction, Numerical Examples

Delta (%) Decimal Hex Binary

+100 – 1/216 +32,767 0x7FFF 0111 1111 1111 1111

+100/215 +1 0x0001 0000 0000 0000 0001 0 0 0x0000 0000 0000 0000 0000

−100/215 −1 0xFFFF 1111 1111 1111 1111

−200/215 −2 0xFFFE 1111 1111 1111 1110

−100 −32,768 0x8000 1000 0000 0000 0000

Rev. B | Page 25 of 36

Page 26

ADIS16488 Data Sheet

[15:0]

Barometric pressure bias correction factor, low word

10277-022

PIN 1

PIN 23

POINT OF PERCUSSION ALIGNME NT REFERENCE POINT. SEE CONFIG[6].

BAROMETERS

The BR_BIAS_HIGH register (see Tab le 98) and BR_BIAS_LOW register (Tabl e 99) provide an offset control function and use the same format as the output registers, BAROM_OUT and BAROM_LOW.

Table 98. BR_BIAS_HIGH (Page 2, Base Address = 0x42)

Bits Description (Default = 0x0000)

[15:0]

Table 99. BR_BIAS_LOW (Page 2, Base Address = 0x40)

Bits Description (Default = 0x0000)

Barometric pressure bias correction factor, high word Twos complement, ±1.3 bar measurement range, 0 bar = 0x0000, 1 LSB = 40 µbar

Twos complement, ±1.3 bar measurement range, 0 bar = 0x0000, 1 LSB = 40 µbar ÷ 2

= ~0.00061 µbar

RESTORING FACTORY CALIBRATION

Turn to Page 3 (DIN = 0x8003) and set GLOB_CMD[6] = 1 (DIN = 0xA240, DIN = 0xA300) to execute the factory calibration restore function. This function resets each user calibration register to zero, resets all sensor data to 0, and automatically updates the flash memory within 72 ms. See Tabl e 114 for more information on GLOB_CMD.

POINT OF PERCUSSION ALIGNMENT

CONFIG[6] offers a point of percussion alignment function that maps the accelerometer sensors to the corner of the package identified in Figure 24. To activate this feature, turn to Page 3 (DIN = 0x8003), then set CONFIG[6] = 1 (DIN = 0x8A40, DIN = 0x8B00). See Tab l e 74 for more information on the CONFIG register.

Figure 24. Point of Percussion Reference Point

Rev. B | Page 26 of 36

Page 27

Data Sheet ADIS16488

[15:0]

Bits

Description (Default = 0x0000)

Not used

X-axis gyroscope alarm (1 = enabled)

ALARMS

Each sensor has an independent alarm function that provides controls for alarm magnitude, polarity, and enabling a dynamic rate-of-change option. The ALM_STS register (see Ta bl e 49) contains the alarm output flags and the FNCTIO_CTRL register (see Tab l e 117) provides an option for configuring one of the digital I/O lines as an alarm indicator.

STATIC ALARM USE

The static alarm setting compares each sensor’s output with the trigger settings in the xx_ALM_MAGN registers (see Tab l e 100, Tabl e 101, Tab l e 102, Tabl e 103, Tab l e 104, Ta b l e 105, Ta b l e 106, Tabl e 107, Table 108, and Ta b l e 109) of that sensor. The polarity controls for each alarm are in the ALM_CNFG_x registers (see Tabl e 110, Tab le 111, Tabl e 112). The polarity establishes whether greater than or less than produces an alarm condition. The comparison between the xx_ALM_MAGN value and the output data only applies to the upper word or 16 bits of the output data.

DYNAMIC ALARM USE

The dynamic alarm setting provides the option of comparing the change in each sensor’s output over a period of 48.7 ms with that sensor’s xx_ALM_MAGN register.

Table 100. XG_ALM_MAGN (Page 3, Base Address = 0x28)

Bits Description (Default = 0x0000)

[15:0]

X-axis gyroscope alarm threshold settings, Twos complement, 0°/sec = 0x0000, 1 LSB = 0.02°/sec

Table 105. ZA_ALM_MAGN (Page 3, Base Address = 0x32)

Bits Description (Default = 0x0000)

[15:0]

Z-axis accelerometer alarm threshold settings, Twos complement, 0 g = 0x0000, 1 LSB = 0.8 mg

Table 106. XM_ALM_MAGN (Page 3, Base Address = 0x34)

Bits Description (Default = 0x0000)

X-axis magnetometer alarm threshold settings, Twos complement, 0 gauss = 0x0000, 1 LSB = 0.1 mgauss

Table 107. YM_ALM_MAGN (Page 3, Base Address = 0x36)

Bits Description (Default = 0x0000)

[15:0]

Y-axis magnetometer alarm threshold settings, Twos complement, 0 gauss = 0x0000, 1 LSB = 0.1 mgauss

Table 108. ZM_ALM_MAGN (Page 3, Base Address = 0x38)

Bits Description (Default = 0x0000)

Z-axis magnetometer alarm threshold settings, Twos complement, 0 gauss = 0x0000, 1 LSB = 0.1 mgauss

Table 109. BR_ALM_MAGN (Page 3, Base Address = 0x3A)

Bits Description (Default = 0x0000)

[15:0]

Z-axis barometer alarm threshold settings, Twos complement, 0 bar = 0x0000, 1 LSB = 40 µbar

Table 110. ALM_CNFG_0 (Page 3, Base Address = 0x20)

Table 101. YG_ALM_MAGN (Page 3, Base Address = 0x2A)

Bits Description (Default = 0x0000)

[15:0]

Y-axis gyroscope alarm threshold settings, Twos complement, 0°/sec = 0x0000, 1 LSB = 0.02°/sec

Table 102. ZG_ALM_MAGN (Page 3, Base Address = 0x2C)

Bits Description (Default = 0x0000)

[15:0]

Z-axis gyroscope alarm threshold settings, Twos complement, 0°/sec = 0x0000, 1 LSB = 0.02°/sec

Table 103. XA_ALM_MAGN (Page 3, Base Address = 0x2E)

Bits Description (Default = 0x0000)

[15:0]

X-axis accelerometer alarm threshold settings, Twos complement, 0 g = 0x0000, 1 LSB = 0.8 mg

Table 104. YA_ALM_MAGN (Page 3, Base Address = 0x30)

Bits Description (Default = 0x0000)

[15:0]

Y-axis accelerometer alarm threshold settings, Twos complement, 0 g = 0x0000, 1 LSB = 0.8 mg

15 X-axis accelerometer alarm (1 = enabled)

13 X-axis accelerometer alarm polarity (1 = greater than) 12 X-axis accelerometer dynamic enable (1 = enabled) 11 Z-axis gyroscope alarm (1 = enabled) 10 Not used 9 Z-axis gyroscope alarm polarity (1 = greater than) 8 Z-axis gyroscope dynamic enable (1 = enabled) 7 Y-axis gyroscope alarm (1 = enabled) 6 Not used 5 Y-axis gyroscope alarm polarity (1 = greater than) 4 Y-axis gyroscope dynamic enable (1 = enabled)

2 Not used 1 X-axis gyroscope alarm polarity (1 = greater than) 0 X-axis gyroscope dynamic enable (1 = enabled)

Rev. B | Page 27 of 36

Page 28

ADIS16488 Data Sheet

Not used

Y-axis accelerometer dynamic enable (1 = enabled)

Z-axis magnetometer alarm (1 = enabled)

Table 111. ALM_CNFG_1 (Page 3, Base Address = 0x22)

Bits Description (Default = 0x0000)

15 Y-axis magnetometer alarm (1 = enabled) 14 Not used 13 Y-axis magnetometer alarm polarity (1 = greater than) 12 Y-axis magnetometer dynamic enable (1 = enabled) 11 X-axis magnetometer (1 = enabled) 10 Not used 9 X-axis magnetometer alarm polarity (1 = greater than) 8 X-axis magnetometer dynamic enable (1 = enabled) 7 Z-axis accelerometer alarm (1 = enabled)

5 Z-axis accelerometer alarm polarity (1 = greater than) 4 Z-axis accelerometer dynamic enable (1 = enabled) 3 Y-axis accelerometer alarm (1 = enabled) 2 Not used 1 Y-axis accelerometer alarm polarity (1 = greater than)

Table 112. ALM_CNFG_2 (Page 3, Base Address = 0x24)

Bits Description (Default = 0x0000)

[15:8] Not used 7 Barometer alarm (1 = enabled) 6 Not used 5 Barometer alarm polarity (1 = greater than) 4 Barometer dynamic enable (1 = enabled)

2 Not used 1 Z-axis magnetometer alarm polarity (1 = greater than) 0 Z-axis magnetometer dynamic enable (1 = enabled)

Alarm Example

Tabl e 113 offers an alarm configuration example, which sets the Z-axis gyroscope alarm to trip when Z_GYRO_OUT > 131.1°/sec (0x199B).

Table 113. Alarm Configuration Example

DIN Description

0xAC9B Set ZG_ALM_MAGN[7:0] = 0x9B 0xAD19 Set ZG_ALM_MAGN[15:8] = 0x19 0xA000 Set ALM_CNFG_0[7:0] = 0x00 0xA103 Set ALM_CNFG_0[15:8] = 0x03

Rev. B | Page 28 of 36

Page 29

Data Sheet ADIS16488

Flash memory test

50 ms

RETENTION (Years)

SYSTEM CONTROLS

The ADIS16488 provides a number of system-level controls for managing its operation, which include reset, self-test, calibration, memory management, and I/O configuration.

GLOBAL COMMANDS

The GLOB_CMD register (see Tabl e 114) provides trigger bits for several operations. Write 1 to the appropriate bit in GLOB_CMD to start a function. After the function completes, the bit restores to 0.

Table 114. GLOB_CMD (Page 3, Base Address = 0x02)

Bits Description Execution Time

[15:8] Not used Not applicable 7 Software reset 120 ms 6 Factory calibration restore 75 ms [5:4] Not used Not applicable 3 Flash memory update 375 ms

1 Self-test 12 ms 0 Bias null See Table 70

MEMORY MANAGEMENT

The data retention of the flash memory depends on temperature and the number of write cycles. Figure 25 characterizes the dependence on temperature, and the FLSHCNT_LOW and FLSHCNT_HIGH registers (see Table 115 and Ta bl e 116) provide a running count of flash write cycles. The flash updates every time GLOB_CMD[6], GLOB_CMD[3], or GLOB_CMD[0] is set to 1.

Table 115. FLSHCNT_LOW (Page 2, Base Address = 0x7C)

Bits Description

[15:0] Binary counter; number of flash updates, lower word

Table 116. FLSHCNT_HIGH (Page 2, Base Address = 0x7E)

Bits Description

[15:0] Binary counter; number of flash updates, upper word

Software Reset

Tur n to Page 3 (DIN = 0x8003) and then set GLOB_CMD[7] = 1 (DIN = 0x8280, DIN = 0x8300) to reset the operation, which removes all data, initializes all registers from their flash settings, and starts data collection. This function provides a firmware alternative to the

RST

line (see Ta bl e 5, Pin 8).

Automatic Self-Test

Tur n to Page 3 (DIN = 0x8003) and then set GLOB_CMD[1] = 1 (DIN = 0x8202, then DIN = 0x8300) to run an automatic selftest routine, which executes the following steps:

1. Measure output on each sensor.

2. Activate self-test on each sensor.

3. Measure output on each sensor.

4. Deactivate the self-test on each sensor.

5. Calculate the difference with self-test on and off.

6. Compare the difference with internal pass/fail criteria.

7. Report the pass/fail results for each sensor in DIAG_STS.

After waiting 12 ms for this test to complete, turn to Page 0 (DIN = 0x8000) and read DIAG_STS using DIN = 0x0A00. Note that using an external clock can extend this time. When using an external clock of 100 Hz, this time extends to 35 ms. Note that 100 Hz is too slow for optimal sensor performance.

600

450

300

150

30 40

55 70 85 100 125 135 150

JUNCTION T E M P E R ATURE (°C)

Figure 25. Flash Memory Retention

10277-023

Flash Memory Test

Tur n to Page 3 (DIN = 0x8003), and then set GLOB_CMD[2] = 1 (DIN = 0x8204, DIN = 0x8300) to run a checksum test of the internal flash memory, which compares a factory-programmed value with the current sum of the same memory locations. The result of this test loads into SYS_E_FLAG[6]. Tur n to Page 0 (DIN = 0x8000) and use DIN = 0x0800 to read SYS_E_FLAG.

GENERAL-PURPOSE I/O

There are four general-purpose I/O lines: DIO1, DIO2, DIO3, and DIO4. The FNCTIO_CTRL register controls the basic function of each I/O line, which provides a number of useful functions. Each I/O line will only support one function at a time. In cases where a single line has two different assignments, the enable bit for the lower-priority function will automatically reset to zero and be disabled. The priority is (1) data-ready, (2) sync clock input, (3) alarm indicator, and (4) general-purpose, where 1 identifies the highest priority and 4 indicates the lowest priority.

Rev. B | Page 29 of 36

Page 30

ADIS16488 Data Sheet

General-Purpose I/O Line 4 (DIO4) direction control

Table 117. FNCTIO_CTRL (Page 3, Base Address = 0x06)

Bits Description (Default = 0x000D)

[15:12] Not used 11 Alarm indicator: 1 = enabled, 0 = disabled 10 Alarm indicator polarity: 1 = positive, 0 = negative [9:8]

7 Sync clock input enable: 1 = enabled, 0 = disabled 6

[5:4]

3 Data-ready enable: 1 = enabled, 0 = disabled 2 Data-ready polarity: 1 = positive, 0 = negative [1:0]

Alarm indicator line selection: 00 = DIO1, 01 = DIO2, 10 = DIO3, 11 = DIO4

Sync clock input polarity: 1 = rising edge, 0 = falling edge

Sync clock input line selection: 00 = DIO1, 01 = DIO2, 10 = DIO3, 11 = DIO4

Data-ready line selection: 00 = DIO1, 01 = DIO2, 10 = DIO3, 11 = DIO4

Data-Ready Indicator

FNCTIO_CTRL[3:0] provide some configuration options for using one of the DIOx lines as a data-ready indicator signal, which can drive a processor’s interrupt control line. The factory default assigns DIO2 as a positive polarity, data-ready signal. Use the following sequence to change this assignment to DIO1 with a negative polarity: turn to Page 3 (DIN = 0x8003) and set FNCTIO_CTRL[3:0] = 1000 (DIN = 0x8608, then DIN = 0x8700). The timing jitter on the data-ready signal is ±1.4 µs.

Input Sync/Clock Control

FNCTIO_CTRL[7:4] provide some configuration options for using one of the DIOx lines as an input synchronization signal for sampling inertial sensor data. For example, use the following sequence to establish DIO4 as a positive polarity, input clock pin and keep the factory default setting for the data-ready function: turn to Page 3 (DIN = 0x8003) and set FNCTIO_CTRL[7:0] = 0xFD (DIN = 0x86FD, then DIN = 0x8700). Note that this command also disables the internal sampling clock, and no data sampling takes place without the input clock signal. When selecting a clock input frequency, consider the 330 Hz sensor bandwidth, because under sampling the sensors can degrade noise and stability performance.

General-Purpose I/O Control

When FNCTIO_CTRL does not configure a DIOx pin, GPIO_CTRL provides register controls for general-purpose use of the pin. GPIO_CTRL[3:0] provides input/output assignment controls for each line. When the DIOx lines are inputs, monitor their level by reading GPIO_CTRL[7:4]. When the DIOx lines are used as outputs, set their level by writing to GPIO_CTRL[7:4]. For example, use the following sequence to set DIO1 and DIO3 as high and low output lines, respectively, and set DIO2 and DIO4 as input lines. Turn to Page 3 (DIN = 0x8003) and set GPIO_CTRL[7:0] = 0x15 (DIN = 0x8815, then DIN = 0x8900).

Table 118. GPIO_CTRL (Page 3, Base Address = 0x08)

Bits Description (Default = 0x00X0)1

[15:8] Don’t care 7 General-Purpose I/O Line 4 (DIO4) data level 6 General-Purpose I/O Line 3 (DIO3) data level 5 General-Purpose I/O Line 2 (DIO2) data level 4 General-Purpose I/O Line 1 (DIO1) data level

(1 = output, 0 = input)

GPIO_CTRL[7:4] reflects levels on DIOx lines.

General-Purpose I/O Line 3 (DIO3) direction control (1 = output, 0 = input)

General-Purpose I/O Line 2 (DIO2) direction control (1 = output, 0 = input)

General-Purpose I/O Line 1 (DIO1) direction control (1 = output, 0 = input)

POWER MANAGEMENT

The SLP_CNT register (see Tab l e 119) provides controls for both power-down mode and sleep modes. The trade-off between power-down mode and sleep mode is between idle power and recovery time. Power-down mode offers the best idle power consumption but requires the most time to recover. Also, all volatile settings are lost during power-down but are preserved during sleep mode.

For timed sleep mode, turn to Page 3 (DIN = 0x8003), write the amount of sleep time to SLP_CNT[7:0] and then, set SLP_CNT[8] = 1 (DIN = 0x9101) to start the sleep period. For a timed powerdown period, change the last command to set SLP_CNT[9] = 1 (DIN = 0x9102). To power down or sleep for an indefinite period, set SLP_CNT[7:0] = 0x00 first, then set either SLP_CNT[8] or SLP_CNT[9] to 1. Note that the command takes effect when the

from sleep or power-down mode, use one of the following options to restore normal operation:

• Assert

• Pulse

from high to low.

RST

low, then high again.

• Cycle the power.

line goes high. To awaken the device

For example, set SLP_CNT[7:0] = 0x64 (DIN = 0x9064), then set SLP_CNT[8] = 1 (DIN = 0x9101) to start a sleep period of 100 seconds.

Rev. B | Page 30 of 36

Page 31

Data Sheet ADIS16488

Table 119. SLP_CNT (Page 3, Base Address = 0x10)

Bits Description

[15:10] Not used 9 Power-down mode 8 Normal sleep mode [7:0]

Programmable time bits; 1 sec/LSB; 0x00 = indefinite

If the sleep mode and power-down mode bits are both set high, the normal sleep mode (SLP_CNT[8]) bit takes precedence.

General-Purpose Registers

The USER_SCR_x registers (see Tabl e 120, Tab l e 121, Tab l e 122, and Tabl e 123) provide four 16-bit registers for storing data.

Table 120. USER_SCR_1 (Page 2, Base Address = 0x74)

Bits Description

[15:0] User-defined

Table 121. USER_SCR_2 (Page 2, Base Address = 0x76)

Bits Description

[15:0] User-defined

Table 122. USER_SCR_3 (Page 2, Base Address = 0x78)

Bits Description

[15:0] User-defined

Table 123. USER_SCR_4 (Page 2, Base Address = 0x7A)

Bits Description

[15:0] User-defined

Real-Time Clock Configuration/Data

The VDDRTC power supply pin (see Tabl e 5, Pin 23) provides a separate supply for the real-time clock (RTC) function. This enables the RTC to keep track of time, even when the main supply (VDD) is off. Configure the RTC function by selecting one of two modes in CONFIG[0] (see Tabl e 74). The real-time clock data is available in the TIME_MS_OUT register (see Ta b l e 124), TIME_DH_OUT register (see Table 125), and TIME_YM_OUT register (see Tab l e 126). When using the elapsed timer mode, the time data registers start at 0x0000 when the device starts up (or resets) and begin keeping time in a manner that is similar to a stopwatch. When using the clock/calendar mode, write the current time to the real-time registers in the following

sequence: seconds (TIME_MS_OUT[5:0]), minutes (TIME_ MS_OUT[13:8]), hours (TIME_DH_OUT[5:0]), day (TIME_DH_OUT[12:8]), month (TIME_YM_OUT[3:0]), and year (TIME_YM_OUT[14:8]). The updates to the timer do not become active until a successful write to the TIME_ YM_OUT[14:8] byte. The real-time clock registers reflect the newly updated values only after the next seconds tick of the clock that follows the write to TIME_YM_OUT[14:8] (year). Writ i ng t o T IM E_ YM_OUT[14:8] activates all timing values; therefore, always write to this location last when updating the timer, even if the year information does not require updating.

Write the current time to each time data register after setting CONFIG[0] = 1 (DIN = 0x8003, DIN = 0x8A01). Note that CONFIG[1] provides a bit for managing daylight savings time. After the CONFIG and TIME_xx_OUT registers are configured, set GLOB_CMD[3] = 1 (DIN = 0x8003, DIN = 0x8204, DIN = 0x8300) to back these settings up in flash, and use a separate 3.3 V source to supply power to the VDDRTC function. Note that access to time data in the TIME_xx_OUT registers requires normal operation (VDD = 3.3 V and full startup), but the timer function only requires that VDDRTC =

3.3 V when the rest of the ADIS16488 is turned off.

Table 124. TIME_MS_OUT (Page 0, Base Address = 0x78)

Bits Description

[15:14] Not used [13:8] Minutes, binary data, range = 0 to 59 [7:6] Not used [5:0] Seconds, binary data, range = 0 to 59

Table 125. TIME_DH_OUT (Page 0, Base Address = 0x7A)

Bits Description

[15:13] Not used [12:8] Day, binary data, range = 1 to 31 [7:6] Not used [5:0] Hours, binary data, range = 0 to 23

Table 126. TIME_YM_OUT (Page 0, Base Address = 0x7C)

Bits Description

[15] Not used [14:8] Year, binary data, range = 0 to 99, relative to 2000 A.D. [7:4] Not used [3:0] Month, binary data, range = 1 to 12

Rev. B | Page 31 of 36

Page 32

ADIS16488 Data Sheet

10277-024

ADIS16488

MOUNTING

HOLES

6.35mm

58.42mm

64.77mm

66.04mm

59.69mm

6.35mm

1.65mm

11.30mm

1RST 2 SCLK 3CS 4 DOUT 5DNC

6 DIN 7GND 8 GND 9GND 10 VDD

11VDD 12 VDD 13DIO1 14 DIO2 15DIO3 16 DIO4

10277-200

10277-025

0.560 BSC 2×

ALIGNMENT HOLES

FOR MATING SOCKET

2.500 BSC 4×

19.800 BSC

39.600 BSC

42.600

21.300 BSC

5 BSC5 BSC

1.642 BSC

NOTES

1. ALL DI M E NS IONS IN mm UNITS.

0.4334 [11.0]

0.0240 [0.610]

0.019685 [0.5000]

(TYP)

0.054 [1.37]

0.0394 [1.00]

0.1800 [4.57]

NONPLATED THRU HOLE 2×

0.022± DIA (TYP)

0.022 DIA THRU HOLE (TYP) NONPLATED THRU HOL E

10277-026

APPLICATIONS INFORMATION

PROTOTYPE INTERFACE BOARD

The ADIS16488/PCBZ includes one ADIS16488AMLZ, one interface printed circuit board (PCB), and four M2 × 0.4 × 18 mm machine screws. The interface PCB provides four holes for

ADIS16488AMLZ attachment and four larger holes for

attaching the interface PCB to another surface. The

ADIS16488AMLZ attachment holes are pre-tapped for M2 ×

0.4 mm machine screws and the four larger holes, located in each corner, support attachment with M2.5 or #4 machine screws. J1 is a dual-row, 2 mm (pitch) connector that works with a number of ribbon cable systems, including 3M Part Number 152212-0100-GB (ribbon crimp connector) and 3M Part Number 3625/12 (ribbon cable). Note that J1 has 16 pads but currently uses a 12-pin connector. The extra pins accommodate future evaluation system plans.

Figure 27 provides the pin assignments for J1. The pin descriptions match those listed in Tab l e 5. The C1 and C2 locations provide solder pads for extra capacitors, which can provide additional filtering for start-up transients and supply noise.

INSTALLATION TIPS

Figure 28 and Figure 29 provide the mechanical design information used for the ADIS16488/PCBZ. Use these figures when implementing a connector-down approach, where the mating connector and the ADIS16488AMLZ are on the same surface. When designing a connector-up system, use the mounting holes shown in Figure 28 as a guide in designing the bulkhead mounting system and use Figure 29 as a guide in developing the mating connector interface on a flexible circuit or other connector system. The suggested torque setting for the attachment hardware is 40 inch-ounces, or 0.2825 N-m.

Figure 26. Physical Diagram for the ADIS16488/PCBZ

Figure 27. ADIS16488/PCBZ J1 Pin Assignments

Rev. B | Page 32 of 36

Figure 28. Suggested Mounting Hole Locations, Connector Down

Figure 29. Suggested Layout and Mechanical Design for the Matin g Connector

Page 33

Data Sheet ADIS16488

10-20-2010-B

BOTTOM VIEW

FRONT VIEW

44.254

44.000

43.746

42.854

42.600

42.346

47.254

47.000

46.746

14.254

14.000

13.746

3.454

3.200

2.946

39.854

39.600

39.346

Ø 2.40 BSC

(4 PLCS)

19.80

2.20 BSC DETAIL A

DETAIL B

5.50 BSC

5.50

BSC

1.00 BSC

1.142 BSC

2.84 BSC

DETAIL A

DETAIL B

1.00 BSC PITCH

0.30 SQ BSC

OUTLINE DIMENSIONS

Figure 30. 24-Lead Module with Connector Interface [MODULE]

(ML-24-6)

Dimensions shown in millimeters

ORDERING GUIDE

1, 2

Model

ADIS16488AMLZ −40°C to +85°C 24-Lead Module with Connector Interface [MODULE] ML-24-6 ADIS16488/PCBZ Interface PCB

Z = RoHS Compliant Part.

The ADIS16488/PCBZ includes one ADIS16488AMLZ and one interface board PCB. See Figure 26 for more information on the interface PCB.

Temperature Range Package Description Package Option

Rev. B | Page 33 of 36

Page 34

ADIS16488 Data Sheet

NOTES

Rev. B | Page 34 of 36

Page 35

Data Sheet ADIS16488

NOTES

Rev. B | Page 35 of 36

Page 36

ADIS16488 Data Sheet

NOTES

Rev. B | Page 36 of 36

Datasheet ADIS16488 Datasheet (ANALOG DEVICES)

FEATURES

GENERAL DESCRIPTION

APPLICATIONS

FUNCTIONAL BLOCK DIAGRAM

TABLE OF CONTENTS

REVISION HISTORY

SPECIFICATIONS

TIMING SPECIFICATIONS

Timing Diagrams

ABSOLUTE MAXIMUM RATINGS

ESD CAUTION

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

TYPICAL PERFORMANCE CHARACTERISTICS

BASIC OPERATION

REGISTER STRUCTURE

SPI COMMUNICATION

DEVICE CONFIGURATION

Dual Memory Structure

READING SENSOR DATA

USER REGISTERS

OUTPUT DATA REGISTERS

INERTIAL SENSOR DATA FORMAT

ROTATION RATE (GYROSCOPE)

ACCELERATION

DELTA ANGLES

DELTA VELOCITY

MAGNETOMETERS

BAROMETER

INTERNAL TEMPERATURE

STATUS/ALARM INDICATORS

FIRMWARE REVISION

PRODUCT IDENTIFICATION

DIGITAL SIGNAL PROCESSING

GYROSCOPES/ACCELEROMETERS

AVERAGING/DECIMATION FILTER

MAGNETOMETER/BAROMETER

FIR FILTER BANKS

Filter Memory Organization

Default Filter Performance

CALIBRATION

GYROSCOPES

Manual Bias Correction

Bias Null Command

Manual Sensitivity Correction

Linear Acceleration on Effect on Gyroscope Bias

ACCELEROMETERS

Manual Bias Correction

Manual Sensitivity Correction

MAGNETOMETERS

Hard-Iron Correction

Soft-Iron Correction Matrix

BAROMETERS

RESTORING FACTORY CALIBRATION

POINT OF PERCUSSION ALIGNMENT

ALARMS

STATIC ALARM USE

DYNAMIC ALARM USE

Alarm Example

Flash memory test

SYSTEM CONTROLS

GLOBAL COMMANDS

MEMORY MANAGEMENT

Software Reset

Automatic Self-Test

GENERAL-PURPOSE I/O

Data-Ready Indicator

Input Sync/Clock Control

General-Purpose I/O Control

POWER MANAGEMENT

General-Purpose Registers

Real-Time Clock Configuration/Data

APPLICATIONS INFORMATION

PROTOTYPE INTERFACE BOARD

INSTALLATION TIPS

OUTLINE DIMENSIONS

ORDERING GUIDE