Freescale 33970 Technical Data

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Freescale Semiconductor

Advance Information

Dual Gauge Driver Integrated

Document Number: MC33970

Rev. 3.0, 1/2007

Circuit with Improved Damping Algorithms

This 33970 is a single-packaged, Serial Peripheral Interface (SPI) controlled, dual step motor gauge driver integrated circuit (IC). This monolithic IC consists of four dual output H-Bridge coil drivers and the associated control logic. Each pair of H-Bridge dri ve rs is used to automatically control the speed, direction, and magnitude of current through the two coils of a two-phase instrumentation step motor, similar to an MMT-licensed AFIC

The 33970 is ideal for use in automotive instrumentation systems requiring distributed and flexible step motor gauge driving. The device also eases the transition to step motors from air core motors by emulating the air core pointer movement with little additional processor bandwidth utilization.

Features

• MMT-Licensed Two-Phase Step Motor Compatible

• Minimal Processor Overhead Required

• Fully Integrated Pointer Movement and Position State Machine with Air Core Movement Emulation

• 4096 Possible Steady State Pointer Positions

• 340° Maximum Pointer Sweep

• Fixed Maximum Acceleration and Deceleration of 4500°/s2

• Maximum Pointer Velocity of 400°/s

• Analog Microstepping (12 Steps/Degree of Pointer Movement)

• Pointer Calibration and Return to Zero

• SPI-Controlled 16-Bit Word

• Calibratable Internal Clock

• Low Sleep Mode Current

• Backward Compatible with MC33991

• Improved Pointer Movement, Diagnostics, and Return to Zero (RTZ)

• Pb-Free Packaging Designated by Suffix Code EG

6405.

IMPROVED GAUGE DRIVER

ORDERING INFORMATION

Device

MC33970DW/R2

MCZ33970EG/R2

33970

INTEGRATED CIRCUIT

DW SUFFIX

EG SUFFIX (Pb-FREE)

98ASB42344B 24-PIN SOICW

Temperature

Range (T

-40°C to 125°C 24 SOICW

)

Package

PWR

33970

5.0 V

Regulator

MCU

Figure 1. 33970 Simplified Application Diagram

* This document contains certain information on a new product. Specifications and information herein are subject to change without notice.

VPWR

VDD

RTZ RST CS SCLK SI SO

SIN0+

SIN0-

Motor 0

COS0+

COS0-

SIN1+

SIN1-

Motor 1

COS1+

COS1-

GND

INTERNAL BLOCK DIAGRAM

VPWR

VDD

SCLK

RST

INTERNAL

REGULATOR

COS0

SPI

LOGIC

STATE

MACHINE

UNDER

AND

OVERVOLTAGE

DETECT

ILIM

OVERTEMPERATURE

DETECT

SIGMA-DELTA

ADC

SIN0

COS1

H-BRIDGE

AND

CONTROL

SIN1

MULTIPLEXER

COS0+ COS0-

SIN0+ SIN0-

COS1+ COS1-

SIN1+ SIN1-

VDD

OSCILLATOR

AGND

GND (8)

RTZ

Figure 2. 33970 Simplified Internal Block Diagram

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Analog Integrated Circuit Device Data

2 Freescale Semiconductor

PIN CONNECTIONS

COS0+

COS0-

SIN0+

SIN0-

GND GND GND GND

SCLK

1 2 3 4 5 6 7 8 9 10 11

24 23 22 21 20 19 18 17 16 15 14 13

COS1+ COS1SIN1+ SIN1GND GND GND GND VPWR RST VDD RTZ

Figure 3. 33970 Pin Connections

Table 1. 33970 Pin Definitions

A functional description of each pin can be found in the Functional Pin Description section beginning on page 10.

Pin Number Pin Name Pin Function Formal Name Definition

1 2 3 4

5 – 8,

17–

9 CS Input Chip Select

10 SCLK Input Serial Clock

11 SO Output Serial Output

12 SI Input Serial Input

13 RTZ Output Multiplexed Output

14 VDD Input Voltage 15 RST Input Reset 16 VPWR Input Battery Voltage 21

22 23 24

COS0+ COS0−

SIN0+ SIN0−

GND Ground Ground

SIN1−

SIN1+ COS1− COS1+

Output H-Bridge Outputs 0

Output H-Bridge Outputs 1

Each pin is the output pin of a half bridge, designed to source or sink current.

These pins serve as the ground for the source of the low-side output transistors as well as the logic portion of the device.

This pin is connected to a chip select output of a LSI IC. This pin is connected to the SCLK pin of the master device and acts as a

bit clock for the SPI port. This pin is connected to the SPI Serial Data Input pin of the master

device, or to the SI pin of the next device in a daisy chain. This pin is connected to the SPI Serial Data Output pin of the master

device from which it receives output command data. This is a multiplexed output pin, for the non-driven coil, during a Return to

Zero (RTZ) event. This SPI and logic power supply input will work with 5.0 V supplies. This input has an internal active pull-up. Power supply. Each of these pins are the output pin of a half bridge, designed to source

or sink current.

33970

Analog Integrated Circuit Device Data Freescale Semiconductor 3

ELECTRICAL CHARACTERISTICS

MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

MAXIMUM RATINGS

Table 2. Maximum Ratings

All voltages are with respect to ground unless otherwise noted. Exceeding these ratings may cause a malfunction or

permanent damage to the device.

Ratings Symbol Value Unit

ELECTRICAL RATINGS

Power Supply Voltage

Steady State Input Pin Voltage SIN +/- COS +/- Continuous Per Output Current ESD Voltage

(1)

(2)

(3)

Human Body Model

Machine Model

THERMAL RATINGS

Storage Temperature Operating Junction Temperature Thermal Resistance

Junction to Ambient

Junction to Lead

THERMAL RESISTANCE

Peak Package Reflow Temperature During Reflow

(4), (5)

Notes

1. Exceeding voltage limits on Input pins may cause permanent damage to the device.

2. Output continuous output rating so long as maximum junction temperature is not exceeded. Operation at 125°C ambient temperature will require maximum output current computation using package thermal resistances.

3. ESD1 testing is performed in accordance with the Human Body Model (C accordance with the Machine Model (C

= 200 pF, R

ZAP

= 0 Ω).

4. Pin soldering temperature limit is for 10 seconds maximum duration. Not designed for immersion soldering. Exceeding these limits may cause malfunction or permanent damage to the device.

5. Freescale’s Package Reflow capability meets Pb-free requirements for JEDEC standard J-STD-020C. For Peak Package Reflow Temperature and Moisture Sensitivity Levels (MSL), Go to www.freescale.com, search by part number [e.g. remove prefixes/suffixes and enter the core ID to view all orderable parts. (i.e. MC33xxxD enter 33xxx), and review parametrics.

PWR(SUS)

OUTMAX

= 100 pF, R

ZAP

V V

R R

ESD1 ESD2

STG

PPRT

-0.3 to 41

-0.3 to 7.0 V 40 mA

±2000

±200

-55 to 150 °C

-40 to 150 °C

°C/W 60 20

Note 5

= 1500 Ω), ESD2 testing is performed in

ZAP

°C

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Analog Integrated Circuit Device Data

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STATIC ELECTRICAL CHARACTERISTICS

ELECTRICAL CHARACTERISTICS

STATIC ELECTRICAL CHARACTERISTICS

Table 3. Static Electrical Characteristics

Characteristics noted under conditions 4.75 V < VDD < 5.25 V, -40°C < TA < 125°C, GND = 0 V unless otherwise noted. Typical

values noted reflect the approximate parameter means at T

Characteristic Symbol Min Typ Max Unit

POWER INPUT

Supply Voltage Range

Fully Operational Limited Operational

VPWR Supply Current

Gauge 1 and 2 Outputs ON, No Output Loads

VPWR Supply Current (All Outputs Disabled)

Reset = Logic [0], VDD = 5.0 V Reset = Logic [0], VDD = 0 V

Overvoltage Detection Level Undervoltage Detection Level Logic Supply Voltage Range (5.0 V Nominal Supply) Under VDD Logic Reset VDD Supply Current

Sleep: Reset Logic [0] Outputs Enabled

POWER OUTPUTS

Microstep Output (Measured Across Coil Outputs) SIN0,1, ± (COS0,1, ±) (refer to Table 1)

= 200 Ω

OUT

Steps 6, 18 (0, 12) Steps 5, 7, 17, 19 (1, 11, 13, 23) Steps 4, 8, 16, 20 (2, 10, 14, 22) Steps 3, 9, 15, 21 (3, 9, 15, 21) Steps 2, 10, 14, 22 (4, 8,16, 20) Steps 1, 11, 13, 23 (5, 7, 17, 19) Steps 0, 12 (6, 18)

Full Step Active Output (Measured Across Coil Outputs) SIN0, 1, ± (COS0, 1, ±) (see Figure 9, page 23)

Steps 1, 3 (0, 2)

Microstep, Full Step Output (Measured from Coil Low Side to Ground) SIN0, 1, ± (COS0, 1, ±), I

Notes

6. Outputs and logic remain active; however, the larger coil voltage levels may be clipped. The reduction in drive voltage may result in a loss of position control.

7. The logic will reset at some level below the specified Limited Operational minimum.

8. Outputs will disable and must be re-enabled via the PECCR command.

9. Outputs remain active; however, the reduction in drive voltage may result in a loss of position control.

(6), (7)

OUT

(8)

(9)

= 30 mA

= 25°C under nominal conditions unless otherwise noted.

PWR

PWR(ON)

6.5

4.0

– –

26 26

– 4.0 6.0

PWSLP1

PWRSLP2

PWROV

PWRUV

DDUV

DD(OFF)

DD(ON)

ST6

ST5

ST4

ST3

ST2

ST1

ST0

– –

42 15

60 25

26 32 38 V

5.0 5.6 6.2 V

4.5 5.0 5.5 V – – 4.5 V

4.82

0.94 V

0.84 V

0.68 V

0.47 V

0.23 V

-0.1

– –

ST6 ST6 ST6 ST6 ST6

1.0

5.3

0.97 V

0.87 V

0.71 V

0.50 V

0.26 V

0.0

ST6 ST6 ST6 ST6 ST6

1.8

6.0

1.0 V

0.96 V

0.8 V

0.57 V

0.31 V

0.1

ST6

ST6 ST6

4.9 5.3 6.0

0.0 0.1 0.3

µA

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Analog Integrated Circuit Device Data Freescale Semiconductor 5

ELECTRICAL CHARACTERISTICS

STATIC ELECTRICAL CHARACTERISTICS

Table 3. Static Electrical Characteristics (continued)

Characteristics noted under conditions 4.75 V < VDD < 5.25 V, -40°C < TA < 125°C, GND = 0 V unless otherwise noted. Typical

values noted reflect the approximate parameter means at T

Characteristic Symbol Min Typ Max Unit

POWER OUTPUTS (continued)

Output Flyback Clamp Output Current Limit (Output = VST6) Overtemperature Shutdown Overtemperature Hysteresis

CONTROL I/O

Input Logic High Voltage Input Logic Low Voltage Input Logic Voltage Hysteresis Input Logic Pull Down Current (SI, SCLK) Input Logic Pull-Up Current (CS, RST) SO High-State Output Voltage (IOH = 1.0 mA) SO Low-State Output Voltage (IOL = -1.6 mA) SO Tri-State Leakage Current (CS ≥ 3.5 V) Input Capacitance SO Tri-State Capacitance

ANALOG TO DIGITAL CONVERTER (RTZ ACCUMULATOR COUNT)

ADC Gain

(10), (13)

Notes

10. This parameter is guaranteed by design; however, it is not production tested.

11. VDD = 5.0 V.

12. Capacitance not measured. This parameter is guaranteed by design; however, it is not production tested.

13. Reference Figure 8, RTZ Accumulator (Typical)

(10)

(11)

(10)

(12)

= 25°C under nominal conditions unless otherwise noted.

LIM

HYST

IN(HYST)

DWN

SOH

SOL

SOLK

ADC

– V

+ 0.5 V

ST6

+ 1.0 V

ST6

40 100 170 mA

155 – 180 °C

8.0 – 16 °C

2.0 – – V – – 0.8 V – 100 – mV

3.0 – 20 µA

5.0 – 20 µA

0.8 V

– – V

– 0.2 0.4 V

-5.0 0 5.0 µA – 4.0 12 pF – – 20 pF

100 188 270 Counts/V/

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Analog Integrated Circuit Device Data

6 Freescale Semiconductor

DYNAMIC ELECTRICAL CHARACTERISTICS

ELECTRICAL CHARACTERISTICS

DYNAMIC ELECTRICAL CHARACTERISTICS

Table 4. Dynamic Electrical Characteristics

Characteristics noted under conditions 4.75 V < VDD < 5.25 V, -40°C < TA < 125°C, GND = 0 V unless otherwise noted. Typical

values noted reflect the approximate parameter means at TA = 25°C under nominal conditions unless otherwise noted.

Characteristic Symbol Min Typ Max Unit

POWER OUTPUT AND CLOCK TIMINGS

SIN, COS Output Turn ON Delay Time (Time from Rising CS Enabling Outputs to Steady State Coil Voltages and Currents)

SIN, COS Output Turn OFF Delay Time (Time from Rising CS Disables Outputs to Steady State Coil Voltages and Currents)

(14)

Uncalibrated Oscillator Cycle Time Calibrated Oscillator Cycle Time

Cal Pulse = 8.0 µs, PECCR D4 = Logic [0]

Cal pulse = 8.0 µs, PECCR D4 = Logic [1] Maximum Pointer Speed Maximum Pointer Acceleration

SPI INTERFACE TIMING

(15)

(16)

Recommended Frequency of SPI Operation Falling Edge of CS to Rising Edge of SCLK (Required Setup Time) Falling Edge of SCLK to Rising Edge of CS (Required Setup Time) SI to Falling Edge of SCLK (Required Setup Time)

(17)

Required High State Duration of SCLK (Required Setup Time) Required Low State Duration of SCLK (Required Setup Time) Falling Edge of SCLK to SI (Required Hold Time)

(17)

SO Rise Time

CL = 200 pF SO Fall Time

CL = 200 pF SI, CS, SCLK, Incoming Signal Rise Time

SI, CS, SCLK, Incoming Signal Fall Time Falling Edge of RST to Rising Edge of RST (Required Setup Time) Rising Edge of CS to Falling Edge of CS (Required Setup Time) Rising Edge of RST to Falling Edge of CS (Required Setup Time)

(18)

(17)

(17), (19)

(17)

Notes

14. Maximum specified time for the 33970 is the minimum guaranteed time needed from the microcontroller.

15. The minimum and maximum value will vary proportionally to the internal clock tolerance. These numbers are based on an ideally calibrated clock frequency of 1.0

MHz. These are not 100 percent tested.

16. The device shall meet all SPI interface timing requirements specified in the SPI Interface Timing section of this table, over the temperature range specified. Digital interface timing is based on a symmetrical 50 percent duty cycle SCLK Clock Period of 333 ns. The device shall be fully functional for slower clock speeds. See

Figure 4 and 5.

17. The maximum setup time specified for the 33970 is the minimum time needed from the microcontroller to guarantee correct operation.

18. Rise and Fall time of incoming SI, CS, and SCLK signals suggested for design consideration to prevent the occurrence of double pulsing.

19. The value is for a 1.0 MHz calibrated internal clock. The value will change proportionally as the internal clock frequency changes

DLY (ON)

DLY (OFF)

CLU

CLC

MAX

SPI

LEAD

LAG

ISU

WSCLKH

WSCLKL

(HOLD)

RSI

RST

– – 1.0

0.65 1.0 1.7 µs µs

1.0

0.9

1.1

1.0

1.2

1.1 – – 400 °/s – – 4500 °/s

– 1.0 3.0 MHz – 50 167 ns – 50 167 ns – 25 83 ns – – 167 ns – – 167 ns – 25 83 ns

– 25 50

– 25 50 – – 50 ns

– – 50 ns – – 3.0 µs – – 5.0 µs – – 5.0 µs

33970

Analog Integrated Circuit Device Data Freescale Semiconductor 7

ELECTRICAL CHARACTERISTICS

DYNAMIC ELECTRICAL CHARACTERISTICS

Table 4. Dynamic Electrical Characteristics

Characteristics noted under conditions 4.75 V < VDD < 5.25 V, -40°C < TA < 125°C, GND = 0 V unless otherwise noted. Typical

values noted reflect the approximate parameter means at TA = 25°C under nominal conditions unless otherwise noted.

Characteristic Symbol Min Typ Max Unit

(22)

(20)

(21)

SO(EN)

SO(DIS)

VALID

– – 145 ns – 1.3 4.0 µs

– 65 105

Time from Falling Edge of CS to SO Low Impedance Time from Rising Edge of CS to SO High Impedance Time from Rising Edge of SCLK to SO Data Valid

0.2 V

≤ SO ≥ 0.8 VDD, CL = 200 pF

Notes

20. Time required for output status data to be terminated at SO. 1.0 kΩ load on SO

21. Time required for output status data to be available for use at SO. 1.0 kΩ load on SO.

22. Time required to obtain valid data out from SO following the rise of SCLK.

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Analog Integrated Circuit Device Data

8 Freescale Semiconductor

RST

SCLK

WRST

0.7 V

0.2 V

0.7 V

LEAD

0.7 V

0.2 V

TIMING DIAGRAMS

WSCLKh

LEAD

WSCLKl

SI(HOLD)

ELECTRICAL CHARACTERISTICS

0.7 V

RSI

FSI

LAG

TIMING DIAGRAMS

Don’t CareValidValid Don’t CareDon’t Care

SCLK

Low-to-High

High-to-Low

Figure 4. Input Timing Switching Characteristics

0.7 V

0.2 V

FSI

1.0 V

3.5 V

0.2 V

0.7 V

SO(EN)

SO(DIS)

RSI

VALID

50%

RSO

FSO

Figure 5. Valid Data Delay Time and Valid Time Waveforms

33970

Analog Integrated Circuit Device Data Freescale Semiconductor 9

FUNCTIONAL DESCRIPTION

INTRODUCTION

FUNCTIONAL DESCRIPTION

INTRODUCTION

This 33970 is a single-packaged, Serial Peripheral Interface (SPI) controlled, dual step motor gauge driver integrated circuit (IC). This monolithic IC consists of four dual output H-Bridge coil drivers and the associated control logic. Each pair of H-Bridge drivers is used to automatically control the speed, direction, and magnitude of current through the two coils of a two-phase instrumentation step motor, similar to an MMT-licensed AFIC

6405.

FUNCTIONAL PIN DESCRIPTION

H-Bridge Outputs 0 (COS0+, COS0-, SIN0+, SIN0-)

Each pin is the output pin of a half bridge, designed to source or sink current. The H-Bridge pins linearly drive the sine and cosine coils of two separate step motors to provide four-quadrant operation.

GROUND (GND)

These pins serve as the ground for the source of the lowside output transistors as well as the logic portion of the device. They also help dissipate heat from the device.

CHIP SELECT (CS)

The CS pin enables communication with the master device. When this pin is in a logic [0] state, the 33970 is capable of transferring information to, and receiving information from, the master. The 33970 latches data in from the Input Shift registers to the addressed registers on the rising edge of when CS is logic [0]. When CS is logic high, signals at the SCLK and SI pins are ignored and the SO pin is tri-stated (high impedance). state to a logic internal pull-up (lUP) connected to the pin, as specified in the section of the Static Electrical Characteristics table entitled

CONTROL I/O, which is found on page 6.

CS. The output driver on the SO pin is enabled

CS will only be transitioned from a logic [1]

[0] state when SCLK is a logic [0]. CS has an

SERIAL CLOCK (SCLK)

SCLK clocks the Internal Shift registers of the 33970 device. The Serial Input (SI) pin accepts data into the Input Shift register on the falling edge of the SCLK signal, while the Serial Output pin (SO) shifts data information out of the SO Line Driver on the rising edge of the SCLK signal. It is important that the SCLK pin be in a logic [0] state whenever

CS makes any transition. SCLK has an internal pull down

the

), as specified in the section of the Static Electrical

DWN

Characteristics table entitled on page 6. When CS is logic [1], signals at the SCLK and SI pins are ignored and SO is tri-stated (high impedance). Refer to the data transfer timing diagrams in on page 12.

CONTROL I/O, which is found

Figure 6 and Figure 7

SERIAL OUTPUT (SO)

The SO data pin is a tri-stateable output from the Shift register. The Status register bits are the first 16 bits shifted out. Those bits are followed by the message bits clocked in FIFO, when the device is in a daisy chain connection or being sent words that are multiples of 16 bits. Data is shifted on the rising edge of the SCLK signal. The SO pin will remain in a high impedance state until the state.

CS pin is put into a logic low

SERIAL INPUT (SI)

The SI pin is the input of the Serial Peripheral Interface (SPI). Serial Input (SI) information is read on the falling edge of SCLK. A 16-bit stream of serial data is required on the SI pin, beginning with the most significant bit (MSB). Messages that are not multiples of 16 bits (e.g., daisy chained device messages) are ignored. After transmitting a 16-bit word, the

CS pin must be de-asserted (logic [1]) before transmitting a

new word. SI information is ignored when CS is in a logic high state.

Multiplexed Output (RTZ)

This is a multiplexed output pin, for the non-driven coil, during a Return to Zero (RTZ) event.

Voltage (VDD)

This SPI and logic power supply input will work with 5.0 V supplies.

RESET (RST)

If the master decides to reset the device, or place it into a sleep state, the

RST pin will force all internal logic to the known default

the state. This input has an internal active pull-up.

RST pin is driven to a logic [0]. A logic [0] on

BATTERY VOLTAGE (VPWR)

Power supply.

33970

Analog Integrated Circuit Device Data

10 Freescale Semiconductor

FUNCTIONAL DESCRIPTION

FUNCTIONAL PIN DESCRIPTION

H-BRIDGE OUTPUTS 1 (SIN1-, SIN1+, COS1-, COS1+)

Each of this pins is the output pin of a half bridge, designed

to source or sink current. The H-Bridge pins linearly drive the

sine and cosine coils of two separate step motors to provide four-quadrant operation.

33970

Analog Integrated Circuit Device Data Freescale Semiconductor 11

FUNCTIONAL DEVICE OPERATION

OPERATIONAL MODES

FUNCTIONAL DEVICE OPERATION

OPERATIONAL MODES

SPI PROTOCOL DESCRIPTION

The SPI interface has a full-duplex, three-wire synchronous, 16-bit serial synchronous interface data transfer and four I/O lines associated with it: Chip Select (

CS),

Serial Clock (SCLK), Serial Input (SI), and Serial Output

LOGIC COMMANDS AND REGISTERS

This section provides a description of the 33970 SPI behavior. To follow the explanations below, refer to Table 5 and to the timing diagrams shown in Figure 6 and Figure 7.

Table 5. Data Transfer Timing

Pin Description

CS (1-to-0) CS (0-to-1)

SO pin is enabled. 33970 configuration and desired output states are transferred and executed according to the data in

the Shift registers. Will change state on the rising edge of the SCLK pin signal. Will accept data on the falling edge of the SCLK pin signal.

(SO). The SI/SO pins of the 33970 follow a first in/first out (D15/D0) protocol with both input and output words transferring the most significant bit first. All inputs are compatible with 5.0 V CMOS logic levels.

SCLK

Note SO is tri-stated when CS is logic [1].

D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1

OD15 OD14 OD13 OD12 OD11 OD10 OD9 OD8 OD7 OD6 OD5 OD4 OD3 OD2 OD1

Output shift register is loaded here.

Figure 6. Single 16-Bit Word SPI Communication

SCLK

1. SO is tri-stated when

Notes

2. D15, D14, D13, ..., and D0 refer to the first 16 bits of data into the 33970.

3. D15*, D14*, D13*, ..., and D0* refer to the most recent entry of program data into the 33970.

4. OD15, OD14, OD13, ..., and OD0 refer to the first 16 bits of fault and status data out of the 33970.

D15 D14 D13 D12 D11 D2 D1 D0 D15*D14*D13*D4 D3 D2*D1

OD15 OD14 OD13 OD12 OD11 OD2 OD1 OD0 D15 D14 D13 OD4 OD3 D2 D1

CS is logic [1].

OD0

Figure 7. Multiple 16-Bit Word SPI Communication

33970

Analog Integrated Circuit Device Data

12 Freescale Semiconductor

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

DATA INPUT

The Input Shift register captures data at the falling edge of the SCLK clock. The SCLK clock pulses exactly 16

times only inside the transmission windows (CS in a logic [0] state). By the time the CS signal goes to logic [1] again, the contents of the Input Shift register are transferred to the appropriate internal register, to the address contained in bits 15:13. The minimum time

CS should be kept high depends on the

internal clock speed. That data is specified in the SPI

INTERFACE TIMING section of the Static Electrical

Characteristics, which is found on

page 7. It must be long enough so the internal clock is able to capture the data from the Input Shift register and transfer it to the internal registers.

DATA OUTPUT

At the first rising edge of the SCLK clock, with the CS at

[0], the contents of the selected Status Word register

logic are transferred to the Output Shift register. The first 16 bits clocked out are the status bits. If data continues to clock in before the

CS transitions to a logic [1], the device begins to

shift out the data previously clocked in FIFO after the CS first transitioned to logic [0].

COMMUNICATION MEMORY MAPS AND REGISTER DESCRIPTIONS

The 33970 device is capable of interfacing directly with a microcontroller via the 16-bit SPI protocol described and specified below. The device is controlled by the microprocessor and reports back status information via the SPI. This section provides a detailed description of all registers accessible via serial interface. The various registers control the behavior of this device.

A message is transmitted by the master beginning with the MSB (D15) and ending with the LSB (D0). Multiple messages can be transmitted in succession to accommodate those applications where daisy chaining is desirable, or to confirm transmitted data, as long as the messages are all multiples of

bits. Data is transferred through daisy-chained devices, as

16 illustrated in Figure 7, page 12. If an attempt is made to latch in a message smaller than 16 bits wide, it is ignored.

The 33970 uses six registers to configure the device, control the state of the four H-bridge outputs, and determine the type of status information that is clocked back to the master. The registers are addressed via D15:D13 of the incoming SPI word (refer to

Table 6).

MODULE MEMORY MAP

Various registers of the 33970 SPI module are addressed by the three MSBs of the 16-bit word received serially. Functions to be controlled include:

• Individual gauge drive enabling

• Power-up/down

• Internal clock calibration

• Gauge pointer position and velocity

• Gauge pointer zeroing

• Air core motor movement emulation

• Status information

Status reporting includes:

• Individual gauge overtemperature condition

• Battery overvoltage

• Battery undervoltage

• Pointer zeroing status

• Internal clock status

• Confirmation of coil output changes that should result in pointer movement

• Real time pointer position information

• Real time pointer velocity step information

• Pointer movement direction

• Command pointer position status

• RTZ accumulator value

Table 6 provides the registers available to control the

above functions.

Table 6. Module Memory Map

Address

[15:13]

000 Power, Enable, Calibration,

and Configuration Register 001 Maximum Velocity Register VELR Page 15 010 Gauge 0 Position Register POS0R Page 15 011 Gauge 1 Position Register POS1R Page 15 100 Gauge Return to 0 Register RTZR Page 16 101 Gauge Return to 0

110 Not Used – – 111 Reserved for Test – –

PECCR Page 13

RTZCR Page 17

Configuration

The following section describes the registers, their

addresses, and their impact on device operation.

Address 000 — Power, Enable, Calibration, and Configuration Register (PECCR)

The Power, Enable, Calibration, and Configuration Register is illustrated in 33970 using this register allows the master to (1)

independently enable or disable the output drivers of the two-gauge controllers, (2) (3) disable the air core emulation, (4) select the direction of the pointer movement during pointer positioning and zeroing,

configure the device for the desired status information to

(5) be clocked out into the SO pin, or (6) send a null command for the purpose of reading the status bits. This register is also used to place the 33970 into a low current consumption mode.

Each of the gauge drivers can be enabled by writing a

[1] to their assigned address bits, PE0 and PE1

logic respectively. This feature could be used to disable a driver if

Table 7, page 14. A write to the

calibrate the internal clock,

33970

Analog Integrated Circuit Device Data Freescale Semiconductor 13

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

it is failing or is not being used. The device can be placed into a standby current mode by writing a logic [0] to both PE0 and PE1. During this state, most current consuming circuits are biased off. When in the Standby mode, the internal clock will remain ON.

The internal state machine utilizes a ROM table of step times defining the duration that the motor will spend at each microstep as it accelerates or decelerates to a commanded position. The accuracy of the acceleration and velocity of the motor is directly related to the accuracy of the internal clock. Although the accuracy of the internal clock is temperature independent, the non-calibrated tolerance is +70% to -35%. The 33970 was designed with a feature allowing the internal clock to be software calibrated to a tighter tolerance of ±10%, using the

CS pin and a reference time pulse provided by the

microcontroller.

Calibration of the internal clock is initiated by writing a logic [1] to PE3. The calibration pulse, which must be 8.0 µs for an internal clock speed of 1.0 MHz, will be sent on the CS pin immediately after the SPI word is sent. No other SPI lines will be toggled. A clock calibration will be allowed only if the gauges are disabled or the pointers are not moving, as indicated by status bits MOV0 and MOV1. Additional details are provided in the

INTERNAL CLOCK CALIBRATION

section, beginning on page 26.

Some applications may require a guaranteed maximum pointer velocity and acceleration. Guaranteeing these maximums requires that the nominal internal clock frequency fall below 1.0 clock will always be below 1.0

MHz. The frequency range of the calibrated

MHz if bit PE4 is logic [0] when initiating a calibration command, followed by an 8.0 µs reference pulse. The frequency will be centered at 1.0 MHz if bit PE4 is logic

[1].

Some applications may require a slower calibrated clock due to a lower motor gear reduction ratio. Writing a logic [1] to bit PE2 will slow the internal oscillator by one-third. Slowing the clock accommodates a longer calibration pulse without overrunning the internal counter— a con d i ti on de si g ne d to generate a CAL fault indication. For example, calibration for

a clock frequency of 667

kHz would require a calibration pulse of 12 µs. Unless the internal oscillator is slowed by writing PE2 to logic [1], a 12 µs calibration pulse may overrun the counter and generate a CAL fault indication.

Some applications may require faster pointer positioning than is provided with the air core motor emulation feature. This feature is enabled with the device that is in the default mode. Writing logic

[1] to bit PE5 will disable the air core emulation and provide a constant acceleration and deceleration at the maximum rate.

Bit D6 is logic [0] during a PECCR commands.

The default Pointer Position 0 (PE7 = 0) will be the farthest counter-clockwise position. A logic [1] written to bit PE7 will change the location of the position 0, for the Gauge selected by bit PE8, to the farthest clockwise position. A change in position 0 of only one, or both, of the two coils can be accomplished by using bits PE8 and PE7. Performing an RTZ will always move the pointer to position

0. Exercise care when writing to PECCR bits PE8 and PE7 in order to prevent accidental changes of the position 0 locations.

Bits PE11:PE8 determine the content of the bits clocked

out of the SO pin. When bit PE11 is at logic

[0], the clocked out bits will provide device status. If a logic [1] is written to bit PE11, the bits clocked out of the SO pin, depending upon the state of bits PE10:PE8, provides either:

• Accumulator information and detection status during the RTZ (PE10 logic [0])

• Real time pointer position location at the time CS goes low (PE10 logic [1] and PE9 logic [0]), or

• The real time step position of the pointer as described in the velocity

Table 21, page 24 (PE10, PE9, and PE8

logic [1]).

Additional details are provided in the SO Communication

section beginning on page 18.

If bit PE12 is logic [1] during a PECCR command, the state of PE11:PE0 is ignored. This is referred to as the null command and can be used to read device status without affecting device operation.

Table 7. Power, Enable, Calibration, and Configuration Register (PECCR)

Address 000

Bits D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Read Write

The bits in Table 7 are write-only. PE12 (D12) — Null Command for Status Read

• 0 = Disable

• 1 = Enable PE11 (D11) — Status Select bit. This bit selects the

information clocked out of the SO pin.

• 0 = Device Status (the logic states of PE10, PE9, and

33970

– – – – – – – – – – – – –

PE12 PE11 PE10 PE9 PE8 PE7 0 PE5 PE4 PE3 PE2 PE1 PE0

• 1 = RTZ Accumulator Value, Gauge 0 or 1 Pointer position, or Gauge 0 and 1 Velocity ramp position (depending upon the logic states of PE10, PE9, and PE8)

PE10 (D10) — RTZ Accumulator or Pointer Status Select

bit. This bit is recognized only when PE11 = 1.

• 0 = RTZ Accumulator Value and status

PE8 don’t cares)

• 1 = Pointer Position or Speed

Analog Integrated Circuit Device Data

14 Freescale Semiconductor

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

PE9 (D9) — Pointer Position or Pointer Speed Select bit.

This bit is recognized only if PE11 and PE10 = 1.

• 0 = Gauge 0 or Gauge 1 Pointer Position

• 1 = Gauge 0 and Gauge 1 Pointer Speed

PE8 (D8) — Pointer Position Gauge Select bit. Also the Position 0 of the selected gauge is determined by the PE7 selection. This bit is recognized only if PE11 and PE10 = 1 and PE9 = 0.

• 0 = Gauge 0 position

• 1 = Gauge 1 position

PE7 (D7) — Position 0 Location Select bit. This bit determines the Position 0 of the gauge selected by PE8. RTZ direction will always be to the position 0.

• 0 = Position 0 is the most CCW (counterclockwise) position

• 1 = Position 0 is the most CW (clockwise) position

PE6 (D6) — This bit must be transmitted as logic [0] for

valid PECCR commands.

PE5 (D5) — Air Core Motor Emulation bit. This bit is enabled or disabled (acceleration and deceleration is constant if disabled).

• 0 = Enable

• 1 = Disable

PE4 (D4) — Clock Calibration Frequency Selector

• 0 = Maximum f =1.0 MHz (for 8.0 µs calibration pulse)

• 1 = Nominal f =1.0 MHz (for 8.0 µs calibration pulse)

PE3 (D3) — Clock Calibration Enable bit. This bit enables or disables the clock calibration.

• 0 = Disable

•1 = Enable PE2 (D2) — Oscillator Adjustment

•0 = t

CLU

• 1 = 0.66 x t

CLU

PE1 (D1) — Gauge 1 Enable bit. This bit enables or

disables the output driver of Gauge 1.

• 0 = Disable

•1 = Enable PE0 (D0) — Gauge 0 Enable bit. This bit enables or

disables the output driver of Gauge 0.

• 0 = Disable

•1 = Enable

Address 001 — Maximum Velocity Register (VELR)

The Gauge Maximum Velocity Register is used to set a

maximum velocity for each gauge (refer to

Table 8). Bits

V7:V0 contain a position value from 1– 225 that is representative of the velocity position value described in

Table 21, page 24. The table value becomes the maximum

velocity until it is changed to another value. If a maximum value is chosen greater than the maximum velocity in the acceleration table, the maximum table value becomes the maximum velocity. If the motor is turning at a speed greater than the new maximum, the motor immediately moves down the velocity ramp until the speed falls equal to or below it. Velocity for each motor can be changed simultaneously or independently by writing V8 and/or V9 to a logic V12:V10 must be at logic

[0] for valid VELR commands.

[1]. Bits

Table 8. Maximum Velocity Register (VELR)

Address 001

Bits D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Read Write

The bits in Table 8 are write-only. V12:V10 (D12:D10) — These bits must be transmitted as

logic

V9 (D9) — Gauge 1 Velocity. Specifies whether the maximum velocity determined in the V7: V0 field will apply to Gauge 1.

• 0 = Velocity does not apply to Gauge 1

• 1 = Velocity applies to Gauge 1

V8 (D8) — Gauge 0 Velocity. Specifies whether the maximum velocity specified in the V7: V0 field will apply to Gauge 0.

• 0 = Velocity does not apply to Gauge 0

• 1 = Velocity applies to Gauge 0

– – – – – – – – – – – – – 0 0 0 V9 V8 V7 V6 V5 V4 V3 V2 V1 V0

V7:V0 (D7:D0) — Maximum Velocity. Specifies the

Table 21. This velocity will

[0] for valid VELR commands

maximum velocity position from remain the maximum of the intended gauge until changed by command. Velocities can range from position 1 (00000001) to position 225 (11111111).

Addresses 010 and 011 — Gauge 0/1 Position Registers (POS0R, POS1R)

Gauge 0 Position Register (SI Addresses 010) bits 11: P0 0 are written to when communicating the desired

P0 pointer positions, and Gauge 1 Position Register (SI Address

011) bits P1

11: P1 0 are written to when communicating the desired pointer positions. Commanded positions can range from 0 to 4095. The D12 bit must be at logic

[0] for valid

POS0R and POS1R commands.

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Analog Integrated Circuit Device Data Freescale Semiconductor 15

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

Table 9. Gauge 0 Position Register (POS0R)

Address 010

Bits D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Read Write

– – – – – – – – – – – – – 0 P0 11 P0 10 P0 9 P0 8 P0 7 P0 6 P0 5 P0 4 P0 3 P02 P01 P0 0

The bits in Table 9 are write-only. P0 12 (D12) — This bit must be transmitted as logic [0] for

valid commands.

P0 11:P0 0 (D11:D0) — Desired pointer position of Gauge 0. Pointer positions can range from 0 (000000000000) to position 4095 (111111111111). For a step motor requiring 12

microsteps per degree of pointer

movement, the maximum pointer sweep is 341.25°.

Table 10. Gauge 1 Position Register (POS1R)

Address 011

Bits D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Read Write

The bits in Table 10 are write-only. P1 12 (D12) — This bit must be transmitted as logic [0] for

valid commands.

P1 11:P1 0 (D11:D0) — Desired pointer position of Gauge 1. Pointer positions can range from 0 (000000000000) to position 4095 (111111111111). For a step motor requiring 12 movement, the maximum pointer sweep is 341.25° (4095 ÷ 12).

– – – – – – – – – – – – – 0 P1 11 P1 10 P1 9 P1 8 P1 7 P1 6 P1 5 P1 4 P1 3 P1 2 P1 1 P1 0

driven coil is integrated and its results are stored in an accumulator.

A logic [1] written to bit RZ1 enables a Return to Zero for Gauge 0 if RZ0 is logic [0], and Gauge 1 if RZ0 is logic [1], respectively. Similarly, a logic [0] written to bit RZ1 disables a

0 when RZ0 is logic [0], and

microsteps per degree of pointer

Return to Zero for Gauge Gauge 1 when RZ0 is logic [1], respectively.

Bits D12:D5 and D3:D2 must be at logic [0] for valid RTZR commands.

Bit RZ4 is used to enable an unconditional RTZ event. A

Address 100 — Gauge Return to Zero Register (RTZR)

Gauge Return to Zero Register (RTZR) (refer to Table 11) is written to return the gauge pointers to the zero position. During an RTZ event, the pointer is returned to zero using full steps, where only one coil is driven at any point in time. The

[0] results in a typical RTZ event, automatically

logic providing a Stop when a stall condition is detected. A logic [1] will result in RTZ movement, causing a Stop if a logic [0] is written to bit RZ0. This feature is useful during development and characterization of RTZ requirements.

back electromotive force (EMF) signal present on the non-

Table 11. Return to Zero Register (RTZR)

Address 100

Bits D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Read Write

The register bits in Table 11 are write-only. RZ12:RZ5 (D12:D5) — These bits must be transmitted as

logic

RZ4 (D4) — This bit is used to enable an unconditional

RTZ event.

• 0 = Automatic Return to Zero

• 1 = Unconditional Return to Zero

– – – – – – – – – – – – – 0 0 0 0 0 0 0 0 RZ4 0 RZ2 RZ1 RZ0

RZ3 (D3) — This bit must be transmitted as logic [0] for

valid commands.

[0] for valid commands.

RZ2 (D2) — Return to Zero Direction bit. This bit is used to properly sequence the integrator, depending upon the desired zeroing direction.

• 0 = Return to Zero will occur in the CCW direction = 0)

(PE7

• 1 = Return to Zero will occur in the CW direction

(PE7

= 1)

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Analog Integrated Circuit Device Data

16 Freescale Semiconductor

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

RZ1 (D1) — Return to Zero Direction. This bit commands

the selected gauge to return the pointer to zero position.

• 0 = Return to Zero Disabled

• 1 = Return to Zero Enabled RZ0 (D0) — Gauge Select: Gauge 0/Gauge 1. This bit

selects the gauge to be commanded.

• 0 = Selects Gauge 0

• 1 = Selects Gauge 1

Address 101 — Gauge Return to Zero Configuration Register

Gauge Return to Zero Configuration Register (RTZCR) is

used to configure the Return to Zero Event (refer to

Table 12). It is written to modify the step time, or rate; at

which the pointer moves during an RTZ event. Also, the integration blanking time, which is the time immediately following the transition of a coil from a driven state to an open state in the RTZ mode, is adjustable with this command. Finally, this command is used to adjust the threshold of the RTZ integration register.

The values used for this register should be selected during development to optimize the RTZ for each application. Selecting an RTZ step rate resulting in consistently successful zero detections depends on a clear understanding of the motor characteristics. Specifically, resonant frequencies exist due to the interaction between the motor and the pointer. This command allows movement of the RTZ pointer speed away from these frequencies. Also, some motors require a significant amount of time for the pointer to settle to a steady state position when moving from one full step position to the next. Consistent and accurate integration values require the pointer be stationary at the end of the full step time.

Bits RC3:RC0, RC12:RC11, and RC4 determine the time spent at each full step during an RTZ event. Bits RC3:RC0 are used to select a (1111) in increments of 4.096 ms (refer to

∆t ranging from 0 ms (0000) to 61.44 ms

Table 13). The ∆t

is multiplied by the factor M, which is defined by bits RC12:RC11. The product is then added to the blanking time, selected using bit RC4, to generate the full step time. The multiplier selected with RC12:RC11 will be 1 4

(10) as illustrated in the equations below. Note that the

(00), 2 (01), or

RC12:RC11 value of 8 (11) is not recommended for use in a product design application, because of the potential for an RTZ accumulator internal overflow, due to the long time step. The blanking time is either 512

µs when RC4 is logic [0], or

Table 12. RTZCR SI Register Assignment

µs when it is logic [1].The full step time is generated

768 using the following equations:

When D3:D0 (RC3:RC0) ≠ 0000

Full Step (t) = ∆t x M + blanking (t)(1)

When D3:D0 (RC3:RC0) = 0000

Full Step (t) = blanking (t) + 2.048 ms(2)

Note In equation (2), a 2.048 ms offset is added to the full step time when the RC:3:RC0 = 0000. The full step time default value after a logic reset is 12.80 ms (RC12:RC11

= 00, RC4 = 0, and RC3:RC0 = 0011).

If there are two full steps per degree of pointer movement, the pointer speed is 1/(FullStep

x 2) deg/s.

Detecting pointer movement is accomplished by integrating the EMF present in the non-driven coil during the RTZ event. The integration circuitry is implemented using a Sigma-Delta converter resulting in the placement of a value in the 15-bit RTZ accumulator at the end of each full step. The value in the RTZ accumulator represents the change in flux and is compared to a threshold. Values above the threshold indicate a pointer is moving. Values below the threshold indicate a stalled pointer, thereby resulting in the cessation of the RTZ event.

The RTZ accumulator bits are signed and represented in two’s complement. After a full step of integration, a sign bit of 0 is the indicator of an accumulator exceeding the decision threshold of 0, and the pointer is assumed to still be moving. Similarly, if the sign bit is logic [1] after a full step of integration, the accumulator value is negative and the pointer is assumed to be stopped. The integrator and accumulator are initialized after each full step. If the PECCR command is written to clock out the RTZ accumulator values via the SO, the OD14 bit corresponds to the sign bit of the RTZ accumulator.

Accurate pointer stall detection depends on a correctly preloaded accumulator for specific gauge, pointer, and full step combinations. Bits RC10:RC5 are used to offset the initial RTZ accumulator value, properly detecting a stalled motor. The initial accumulator value at the start of a full step of integration is negative. If the accumulator was correctly preloaded, a free-moving pointer will result in a positive value at the end of the integration time, and a stalled pointer will result in a negative value. The preloaded values associated with each combination of bits RC10:RC5 are illustrated in

Table 14. The accumulator should be loaded with a value

resulting in an accumulator MSB to a logic [1] when the motor is stalled. For the default mode, after a power-up or any reset, the 33970 device sets the accumulator value to -1.

Address 101

Bits D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Read Write

– – – – – – – – – – – – –

RC12 RC11 RC10 RC9 RC8 RC7 RC6 RC5 RC4 RC3 RC2 RC1 RC0

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Analog Integrated Circuit Device Data Freescale Semiconductor 17

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

The bits in Table 12 are write-only.

RC12:RC11 (D12:D11) — These bits, along with RC3:RC0 (D3:D0) and RC4 (D4), determine the full step time and, therefore, the rate at which the pointer will move during an RTZ event. The values of D12:D11 determine the multiplier (M) is used in equation (1) (refer to

page 17).

RC12:RC11 = M

• 00 = 1

• 01 = 2

• 10 = 4

• 11 = 8 (Not to be used for design)

RC10:RC5 (D10:D5) — These bits determine the value preloaded into the RTZ integration accumulator to adjust the detection threshold. Values range from -1 (00000000) to 1099 (11111111) as shown in

Table 14.

RC4 (D4) — This bit determines the RTZ blanking time (blanking (t)).

• 0 = 512 µs

• 1 = 768 µs

RC3:RC0 (D3:D0) — These bits, along with RC12:RC11 (D12:D11) and RC4 (D4), determine the time variables used to calculate the full step times with equations (1) or (2) illustrated above. RC3:RC0 determines the

∆t time. The ∆t values range from 0 (0000) to 61.440 ms (1111) and are shown in Table 13. The default ∆t is 0 (0011).

Note Equation (2) (refer to page 17) is only used to calculate the full step time if RC3:RC0 = 0000. Use equation (1) for all other combinations of RC3:RC0.

Table 13. RTZCR Full Step Time

RC3 RC2 RC1 RC0 ∆t (ms)

0 0 0 0 0 0 0 0 1 4.096 0 0 1 0 8.192 0 0 1 1 12.288 0 1 0 0 16.384 0 1 0 1 20.480 0 1 1 0 24.576 0 1 1 1 28.672 1 0 0 0 32.768 1 0 0 1 36.864 1 0 1 0 40.960 1 0 1 1 45.056 1 1 0 0 49.152 1 1 0 1 53.248 1 1 1 0 57.344 1 1 1 1 61.440

Table 14. RTZCR Accumulator Offset

RC10 RC9 RC8 RC7 RC6 RC5

0 0 0 0 0 0 0 -1 0 0 0 0 0 1 1 -17 0 0 0 0 1 0 2 -33 0 0 0 0 1 1 3 -49 0 0 0 1 0 0 4 -65

. . .

1 1 1 1 1 1 63 -1009

. . .

SO Communication

When the CS pin is pulled low, the internal status register, as configured with the PECCR command bits PE11:PE8, is loaded into the output register and the data is clocked out MSB (OD15) first. Following a

CS transition 0 to 1, the device

determines if the shifted-in message was of a valid length (a valid message length is one that is greater than 0 bits and a multiple of 16 bits), and if so, latches the incoming data into the appropriate registers.

. . .

Preload Value

(PV)

. . .

Initial Accumulator Value = (-16

x PV) -1

. . .

At this time, the SO pin is tri-stated and the status register is now able to accept new status information. Fault status information will be latched and held until the Device Status Output register is selected and it is clocked out via the SO. If the message length was determined to be invalid, the fault information will not be cleared and will be transmitted again during the next valid SPI message. Pointer status information bits (e.g., pointer position, velocity, and commanded position status) will always reflect the real time state of the pointer.

33970

Analog Integrated Circuit Device Data

18 Freescale Semiconductor

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

Any bits clocked out of the SO pin after the first 16 are representative of the initial message bits clocked into the SI pin since the CS pin first transitioned to a logic [0]. This feature is useful for daisy-chaining devices as well as message verification.

As described above, the last valid write to bits PE11:PE8 of the PECCR command determines the nature of the status

5. Gauge 1 and 2 Pointer Velocity Status (refer to

Table 19, page 22)

Once a specific status type is selected, it will not change until either the PECCR command bits PE11:PE8 (D11:D8) are written to select another or the device is reset. Each of the Status types and the PECCR bit necessary to select them are described below.

data that is clocked out of the SO pin.

There are five different types of status information

available:

1. Device Status (refer to Table 15 below)

Device Status Information

Most recent valid PECCR command resulting in the Device Status output:

2. RTZ Accumulator Status (refer to Table 16, page 20)

3. Gauge 0 Pointer Position Status (refer to Table 17, page 21)

4. Gauge 1 Pointer Position Status (refer to Table 18,

D11 D10 D9 D8

0 x x x

x = Don’t care.

page 21)

Table 15. Device Status Output Register

Bits OD15 OD14 OD13 OD12 OD11 OD10 OD9 OD8 OD7 OD6 OD5 OD4 OD3 OD2 OD1 OD0

Read

DIR1 DIR0 0POS1 0POS0 CMD1 CMD0 OV UV CAL OVUV MOV1 MOV0 RTZ1 RTZ0 OT1 OT0

Write

pointer is moving.

– – – – – – – – – – – – – – – –

The bits in Table 15 are read-only bits. DIR1 (OD15) — This bit indicates the direction Gauge 1

overvoltage event will automatically disable the driver outputs. Because the pointer may not be in the expected position, the master may want to re-calibrate the pointer

• 0 = Toward position 0

• 1 = Away from position 0 DIR0 (OD14) — This bit indicates the direction Gauge 0

• 0 = Toward position 0

• 1 = Away from position 0

position with an RTZ command after the voltage returns to a normal level. For an overvoltage event, both gauges must be re-enabled as quickly as this flag returns to logic state machine will continue to operate properly as long as

is within the normal range.

• 0 = Normal range

• 1 = Battery voltage exceeded V

PWROV

[0]. The

0POS1 (OD13) — This bit indicates the configured Position

0 for Gauge 1.

• 0 = Farthest CCW

•1 = Farthest CW 0POS0 (OD12) — This bit indicates the configured Position

0 for Gauge 0.

• 0 = Farthest CCW

•1 = Farthest CW CMD1 (OD11) — This bit indicates whether Gauge 1 is at

the most recently commanded position.

• 0 = At commanded position

• 1 = Not at commanded position CMD0 (OD10) — This bit indicates whether Gauge 0 is at

the most recently commanded position.

• 0 = At commanded position

• 1 = Not at commanded position OV (OD9) — Overvoltage Indication. A logic [1] on this bit

indicates V

voltage exceeded the upper limit of V

PWR

PWROV

since the last SPI communication (refer to the Static Electrical Characteristics table under

POWER INPUT, page 5). An

UV (OD8) — Undervoltage Indication. A logic 1] on this bit

indicates the V

voltage fell below V

PWR

PWRUV

since the last SPI communication (refer to the Static Electrical Characteristics table under

POWER INPUT, page 5). An

undervoltage event is just flagged; however, at some voltage level below 4.0

V, the outputs turn OFF and the state machine resets. Because the pointer may not be in the expected position, the master may want to re-calibrate the pointer position with an RTZ command after the voltage returns to a normal level. For an undervoltage event, both gauges may need to be re-enabled as quickly as this flag returns to logic properly as long as V

[0]. The state machine will continue to operate

is within the normal range.

• 0 = Normal range

• 1 = Battery voltage fell below V

PWRUV

CAL (OD7) — Calibrated Clock out of Specification. A

[1] on this bit indicates the clock count calibrated to a

logic value outside the expected range given the tolerance specified by t

in the Dynamic Electrical Characte ri sti cs

CLC

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Analog Integrated Circuit Device Data Freescale Semiconductor 19

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

table under POWER OUTPUT AND CLOCK TIMINGS, page 7.

• 0 = Clock within spec

• 1 = Clock out of spec

OVUV (OD6) — Undervoltage or Overvoltage Indication. A logic [1] on this bit indicates the V below the V

since the last SPI communication (refer to

PWRUV

the Static Electrical Characteristics table under

voltage fell to a level

PWR

POWER INPUT, page 5). An undervoltage event is just flagged, while

an overvoltage event automatically disables the drive outputs. Because the pointer may not be in the expected position, the master may want to re-calibrate the pointer with an RTZ command after the voltage returns to normal level. For an overvoltage event, both gauges must be re-enabled as soon as this flag returns to logic

[0]. The state machine will continue to operate properly as long as VDD is within the normal range.

• 0 = Normal range

• 1 = Battery voltage fell below V V

PWROV

PWRUV

or exceeded

MOV1 (OD5) — This bit identifies Gauge 1 Movement since last SPI communication. A logic [1] on this bit indicates the Gauge 1 pointer position changed since the last SPI command. This information allows the master to confirm the pointer is moving as commanded.

• 0 = Gauge 1 position has not changed since the last SPI command

• 1 = Gauge 1 pointer position has changed since the last SPI command

MOV0 (OD4) — Gauge 0 Movement Since last SPI Communication. A logic [1] on this bit indicates the Gauge 0 pointer position has changed since the last SPI command. This information allows the master to confirm the pointer is moving as commanded.

• 0 = Gauge 0 position has not changed since the last SPI command

• 1 = Gauge 0 pointer position has changed since the last SPI command

RTZ1 (OD3) — RTZ1 Is Enabled or Disabled. A logic [1] on this bit indicates Gauge 1 is in the process of returning to the zero position as requested with the RTZ command. This bit will continue to indicate a logic [1] until the SPI message following a detection of the zero position, or the RTZ feature is commanded OFF using the RTZ message.

• 0 = Return to Zero disabled

• 1 = Return to Zero enabled successfully

RTZ0 (OD2) — RTZ0 Is Enabled or Disabled. A logic [1] on this bit indicates Gauge 0 is in the process of returning to the zero position as requested with the RTZ command. This bit continues to indicate a logic [1] until the SPI message following a detection of the zero position, or the RTZ feature is commanded OFF using the RTZ message.

• 0 = Return to Zero disabled

• 1 = Return to Zero enabled successfully

OT1 (OD1) — Gauge 1 Junction Overtemperature. A logic [1] on this bit indicates that the coil drive circuitry dedicated to drive Gauge 1 has exceeded the maximum allowable junction temperature since the last SPI communication and that Gauge

1 has been disabled. It is recommended that the pointer be re-calibrated using the RTZ command after re-enabling the gauge using the PECCR command. This bit remains logic

[1] until the gauge is

enabled.

• 0 = Temperature within range

• 1 = Gauge 1 maximum allowable junction temperature condition has been reached

OT0 (OD0) — Gauge 0 Junction Overtemperature. A logic [1] on this bit indicates that the coil drive circuitry dedicated to drive Gauge 0 has exceeded the maximum allowable junction temperature since the last SPI communication and that Gauge

0 has been disabled. It is recommended that the pointer be re-calibrated using the RTZ command after re-enabling the gauge using the PECCR command. This bit remains logic

[1] until the gauge is re-

enabled.

• 0 = Temperature within range

• 1 = Gauge 0 maximum allowable junction temperature condition is reached

RTZ Accumulator Status Information

Most recent valid PECCR command resulting in the RTZ

Accumulator status output:

D11 D10 D9 D8

1 0 x x

x = Don’t care.

Table 16. RTZ Accumulator Status Output Register

Bits OD15 OD14 OD13 OD12 OD11 OD10 OD9 OD8 OD7 OD6 OD5 OD4 OD3 OD2 OD1 OD0 Read Write

on this bit indicates that the Gauge is in the process of returning to the zero position as requested with the RTZ

33970

RTZ ACC14 ACC13 ACC12 ACC11 ACC10 ACC9 ACC8 ACC7 ACC6 ACC5 ACC4 ACC3 AC2C ACC1 ACC0

– – – – – – – – – – – – – – – –

The bits in Table 16 are read-only bits. RTZ (OD15) — RTZ Bit Is Enabled or Disabled. A logic [1]

command. This bit will continue to indicate a logic [1] until the SPI message following a detection of the zero position, or the RTZ feature is commanded OFF using the RTZ message.

• 0 = Return to Zero disabled

Analog Integrated Circuit Device Data

20 Freescale Semiconductor

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

• 1 = Return to Zero enabled successfully

ACC14:ACC0 (OD14:OD0) — These 15 bits are from the RTZ accumulator. They represent the integrated signal present on the non-driven coil during an RTZ event. These bits are logic [0] after power-on reset, or after the

RST pin

transitions from logic [0] to [1]. After an RTZ event, they will represent the last RTZ accumulator result before the RTZ was stopped. ACC14 is the MSB and is the sign bit used for zero detection.

Figure 8. RTZ Accumulator (Typical)

The analog-to-digital converter's linear input range covers the expected magnitude of motor back e.m.f. signals, which is_usually less than 500mV. Input signals greater than this will not cause any damage (the circuit is connected to the motor H-Bridge drivers, and thus is exposed to the full magnitude of the drive voltages), but may cause some small loss of linearity. A typical plot of output vs. input is shown in

Figure 8 for 4ms step times.

Gauge 0 Pointer Position Status Information

Most recent valid PECCR command resulting in the Gauge 0 Pointer Position status output:

D11 D10 D9 D8

1 1 0 0

Table 17. Gauge 0 Pointer Position Status Output Register

Bits OD15 OD14 OD13 OD12 OD11 OD10 OD9 OD8 OD7 OD6 OD5 OD4 OD3 OD2 OD1 OD0

Read

ENB0 DIR0 DIRC0 CMD0 POS11 POS10 POS9 POS8 POS7 POS6 POS5 POS4 POS3 POS2 POS1 POS0

Write

enabled.

moving.

direction of the most recent pointer movement is toward the

– – – – – – – – – – – – – – – –

The bits in Table 17 are read-only bits. ENB0 (OD15) — This bit indicates whether Gauge 0 is

CMD0 (OD12) — This bit indicates whether Gauge 0 is at the most recently commanded position.

• 0 = At commanded position

• 0 = Disabled

• 1 = Enabled DIR0 (OD14) — This bit indicates the direction Gauge 0 is

• 1 = Not at commanded position

POS11:POS0 (OD11:OD0) — These 12 bits represent the actual position of the pointer at the time CS transitions to a logic [0].

• 0 = Toward position 0

• 1 = Away from position 0 DIRC0 (OD13) — This bit is used to determine whether the

Gauge 1 Pointer Position Status Information

Most recent valid PECCR command resulting in the

1 Pointer Velocity status output:

Gauge

last commanded position or away from it.

• 0 = Direction of the pointer movement is toward the commanded position

D11 D10 D9 D8

1 1 0 1

• 1 = Direction of the pointer movement is away from the commanded position

Table 18. Gauge 1 Pointer Position Status Output Register

Bits OD15 OD14 OD13 OD12 OD11 OD10 OD9 OD8 OD7 OD6 OD5 OD4 OD3 OD2 OD1 OD0

Read

ENB1 DIR1 DIRC1 CMD1 POS11 POS10 POS9 POS8 POS7 POS6 POS5 POS4 POS3 POS2 POS1 POS0

Write

– – – – – – – – – – – – – – – –

33970

Analog Integrated Circuit Device Data Freescale Semiconductor 21

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

The bits in Table 18 are read-only bits. ENB1 (OD15) — This bit indicates if Gauge 1 is enabled.

• 0 = Disabled

• 1 = Enabled

DIR1 (OD14) — This bit indicates the direction Gauge 1

pointer is moving.

• 0 = Toward position 0

• 1 = Away from position 0

DIRC1 (OD13) — This bit determines if the direction of the most recent pointer movement is toward, or away from, the last commanded position.

• 0 = Direction of the pointer movement is toward the commanded position

• 1 = Direction of the pointer movement is away from the commanded position

CMD1 (OD12) — This bit indicates if Gauge 1 is at the most

recently commanded position.

• 0 = At commanded position

• 1 = Not at commanded position POS11:POS0 (OD11:OD0) — These 12 bits represent the

actual position of the pointer at the time CS transitions to a

[0].

logic

Gauge 0 and 1 Pointer Velocity Status Information

Most recent valid PECCR command resulting in the

Gauge 0 and 1 Pointer Velocity status output:

D11 D10 D9 D8

1 1 1 x

x = Don’t care.

Table 19. Gauge 0 and 1 Pointer Velocity Status Output Register

Bits OD15 OD14 OD13 OD12 OD11 OD10 OD9 OD8 OD7 OD6 OD5 OD4 OD3 OD2 OD1 OD0 Read Write

velocity position value (refer to Table 21, page 24) indicating the actual velocity of Gauge 1 pointer at the time CS transitions to a logic

velocity position value (refer to Table 21) indicating the actual velocity of Gauge 0 pointer at the time CS transitions to a logic

1V7 1V6 1V5 1V4 1V3 1V2 1V1 1V0 0V7 0V6 0V5 0V4 0V3 0V2 0V1 0V0

– – – – – – – – – – – – – – – –

The bits in Table 19 are read-only bits. 1V7:1V0 (OD15:OD8) — These eight bits represent the

A requirement of the state machine is to ensure the deceleration phase begins at the correct time and pointer position. When commanded, the motor will accelerate constantly to the maximum velocity, then move toward the

[0].

0V7:0V0 (OD7:OD0) — These eight bits represent the

commanded position. Eventually, the pointer will reach the calculated location where the movement has to decelerate, slowing safely to a stop at the desired position. During the deceleration phase, the motor will not exceed the maximum

[0].

deceleration.

During normal operation, both step motor rotors are

STATE MACHINE OPERATION

The two-phase step motor has maximum allowable velocities and acceleration and deceleration.The purpose of the step motor state machine is to drive the motor with maximum performance while remaining within the motor’s voltage, velocity, and acceleration constraints.

microstepped with 24

Figure 9). A complete electrical revolution results in two

degrees of pointer movement. There is a second (smaller) state machine in the IC controlling these microsteps. This state machine receives clockwise or counter-clockwise index commands at intervals, stepping the motor in the appropriate direction by adjusting the current in each coil. Normalized values are provided in

steps per electrical revolution (see

Table 20, page 23.

33970

Analog Integrated Circuit Device Data

22 Freescale Semiconductor

MAX

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

MAX

812345670 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

COIL

MAX

812345670 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Figure 9. Clockwise Microsteps

Table 20. Coil Step Value

Step Angle SINE Angle*

SINE Current

Flow

0 0 0 + 0 0 1 + 255 FF 1 15 0.259 + 66 42 0.965 + 247 F7 2 30 0.5 + 128 80 0.866 + 222 DE 3 45 0.707 + 181 B5 0.707 + 181 B5 4 60 0.866 + 222 DE 0.5 + 128 80 5 75 0.966 + 247 F7 0.259 + 66 42 6 90 1 + 255 FF 0 + 0 0 7 105 0.966 + 247 F7 -0.259 - 66 42 8 120 0.866 + 222 DE -0.5 - 128 80

9 135 0.707 + 181 B5 -0.707 - 181 B5 10 150 0.5 + 128 80 -0.866 - 222 DE 11 165 0.259 + 66 42 -0.966 - 247 F7 12 180 0 + 0 0 -1 - 255 FF 13 195 -0.259 - 66 42 -0.966 - 247 F7 14 210 -0.5 - 128 80 -0.867 - 222 DE 15 225 -0.707 - 181 B5 -0.707 - 181 B5 16 240 -0.866 - 222 DE -0.5 - 128 80 17 255 -0.966 - 247 F7 -0.259 - 66 42 18 270 -1 - 255 FF 0 + 0 0 19 285 -0.966 - 247 F7 0.259 + 66 42 20 300 -0.866 - 222 DE 0.5 + 128 80 21 315 -0.707 - 181 B5 0.707 + 181 B5 22 330 -0.5 - 128 80 0.866 + 222 DE 23 345 -0.259 - 66 42 0.966 + 247 F7

8-Bit Value

(DEC)

8-Bit Value

(HEX)

COS Angle*

COS Current

Flow

8-Bit Value

(DEC)

8-Bit Value

(HEX)

33970

Analog Integrated Circuit Device Data Freescale Semiconductor 23

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

Table 20. Coil Step Value

* Denotes normalized values.

The motor is stepped by providing index commands at intervals. The time between steps defines the motor velocity, and the changing time defines the motor acceleration.

The state machine uses a table to define the allowed time and also the maximum velocity. A useful side effect of the table is that it also allows the direct determination of the position at which the velocity should reduce to allow the motor to stop at the desired position.

The motor equations of motion are generated as follows. (The units of position are steps, and velocity and acceleration are in steps/second and steps/second².)

From an initial position of 0 with an initial velocity (u), the motor position (s) at a time (t) is:

atuts +=

For unit steps, the time between steps is:

++−

auu

=⇒

This defines the time increment between steps when the motor is initially travelling at a velocity u. In the ROM, this time is quantized to multiples of the system clock by rounding upwards, ensuring acceleration never exceeds the allowed value. The actual velocity and acceleration is calculated from the time step actually used.

Using

v2 = u2 + 2as

and

v = u + at

and solving for v in terms of u, s, and t gives:

v =

- u

The correct value of t to use in this equation is the quantized value obtained above.

From these equations a set of recursive equations can be generated to give the allowed time step between motor indexes when the motor is accelerating from a stop to its maximum velocity.

Starting from a position p of 0 and a velocity v of 0, these equations define the time interval between steps at each position. To drive the motor at maximum performance, index

commands are given to the motor at these intervals. A table is generated giving the time step

⎡ ⎢

=∆

⎢ ⎢

⎡⎤

where indicates rounding up.

∆

t at an index position n.

−−

−

∆

⎤

avv

++−

⎥ ⎥

⎥

12−

Pn = n

Note Pn = n. This means on the n th step the motor has indexed by n positions and has been accelerating steadily at the maximum allowed rate. This is critical because it also indicates the minimum distance the motor must travel while decelerating to a stop. For example, the stopping distance is also equal to the current value of n.

The algorithm of pointer movement can be summarized in two steps:

1. The pointer is at the previously commanded position and is not moving.

2. A command to move to a pointer position (other than the current position) has been received. Timed index pulses are sent to the motor driver at an everincreasing rate, according to the time steps in

Table 21, until:

a. The maximum velocity (default or selected) is

reached after which the step time intervals will no longer decrease; or,

b. The distance in steps that remain to travel are less

than the current step time index value. The motor then decelerates by increasing the step times according to

Table 21 until the commanded position

is reached. The state machine controls the deceleration so that the pointer reaches the commanded position efficiently.

An example of the velocity table for a particular motor is provided in Table 21. This motor’s maximum speed is 4800 microsteps/s (at 12 microsteps/degrees), and its maximum acceleration is 54000 microsteps/s

. The table is

quantized to a 1.0 MHz clock.

Table 21. Velocity Table

Velocity Position

0 0 0.00 76 380 2631.6 152 257 3891.1 1 27217 36.7 77 377 2652.5 153 256 3906.3

33970

Time Between

Steps (µs)

Velocity

(µSteps/s)

Velocity

Position

Time Between

Steps (µs)

Velocity

(µSteps/s)

Velocity Position

Time Between

Steps (µs)

Velocity

(µSteps/s)

Analog Integrated Circuit Device Data

24 Freescale Semiconductor

Table 21. Velocity Table (continued)

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

Velocity Position

2 13607 73.5 78 374 2673.8 154 255 3921.6 3 11271 88.7 79 372 2688.2 155 254 3937.0 4 7970 125.5 80 369 2710.0 156 254 3937.0 5 5858 170.7 81 366 2732.2 157 253 3952.6 6 4564 219.1 82 364 2747.3 158 252 3968.3 7 3720 268.8 83 361 2770.1 159 251 3984.1 8 3132 319.3 84 358 2793.3 160 250 4000.0

9 2701 370.2 85 356 2809.0 161 249 4016.1 10 2373 421.4 86 354 2824.9 162 248 4032.3 11 2115 472.8 87 351 2849.0 163 248 4032.3 12 1908 524.1 88 349 2865.3 164 247 4048.6 13 1737 575.7 89 347 2881.8 165 246 4065.0 14 1594 627.4 90 344 2907.0 166 245 4081.6 15 1473 678.9 91 342 2924.0 167 244 4098.4 16 1369 730.5 92 340 2941.2 168 244 4098.4 17 1278 782.5 93 338 2958.6 169 243 4115.2 18 1199 834.0 94 336 2976.2 170 242 4132.2 19 1129 885.7 95 334 2994.0 171 241 4149.4 20 1066 938.1 96 332 3012.0 172 241 4149.4 21 1010 990.1 97 330 3030.3 173 240 4166.7 22 960 1041.7 98 328 3048.8 174 239 4184.1 23 916 1091.7 99 326 3067.5 175 238 4201.7 24 877 1140.3 100 324 3086.4 176 238 4201.7 25 842 1187.6 101 322 3105.6 177 237 4219.4 26 812 1231.5 102 321 3115.3 178 236 4237.3 27 784 1275.5 103 319 3134.8 179 235 4255.3 28 760 1315.8 104 317 3154.6 180 235 4255.3 29 737 1356.9 105 315 3174.6 181 234 4273.5 30 716 1396.6 106 314 3184.7 182 233 4291.8 31 697 1434.7 107 312 3205.1 183 233 4291.8 32 680 1470.6 108 310 3225.8 184 232 4310.3 33 663 1508.3 109 309 3236.2 185 231 4329.0 34 648 1543.2 110 307 3257.3 186 231 4329.0 35 634 1577.3 111 306 3268.0 187 230 4347.8 36 621 1610.3 112 304 3289.5 188 229 4366.8 37 608 1644.7 113 303 3300.3 189 229 4366.8 38 596 1677.9 114 301 3322.3 190 228 4386.0 39 585 1709.4 115 300 3333.3 191 227 4405.3 40 575 1739.1 116 298 3355.7 192 227 4405.3 41 565 1769.9 117 297 3367.0 193 226 4424.8

Time Between

Steps (µs)

Velocity

(µSteps/s)

Velocity Position

Time Between

Steps (µs)

Velocity

(µSteps/s)

Velocity Position

Time Between

Steps (µs)

(µSteps/s)

Velocity

33970

Analog Integrated Circuit Device Data Freescale Semiconductor 25

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

Table 21. Velocity Table (continued)

Velocity Position

42 555 1801.8 118 295 3389.8 194 226 4424.8 43 546 1831.5 119 294 3401.4 195 225 4444.4 44 538 1858.7 120 293 3413.0 196 224 4464.3 45 529 1890.4 121 291 3436.4 197 224 4464.3 46 521 1919.4 122 290 3448.3 198 223 4484.3 47 514 1945.5 123 289 3460.2 199 222 4504.5 48 507 1972.4 124 287 3484.3 200 222 4504.5 49 500 2000.0 125 286 3496.5 201 221 4524.9 50 493 2028.4 126 285 3508.8 202 221 4524.9 51 487 2053.4 127 284 3521.1 203 220 4545.5 52 481 2079.0 128 282 3546.1 204 220 4545.5 53 475 2105.3 129 281 3558.7 205 219 4566.2 54 469 2132.2 130 280 3571.4 206 218 4587.2 55 464 2155.2 131 279 3584.2 207 218 4587.2 56 458 2183.4 132 278 3597.1 208 217 4608.3 57 453 2207.5 133 277 3610.1 209 217 4608.3 58 448 2232.1 134 275 3636.4 210 216 4629.6 59 444 2252.3 135 274 3649.6 211 216 4629.6 60 439 2277.9 136 273 3663.0 212 215 4651.2 61 434 2304.1 137 272 3676.5 213 215 4651.2 62 430 2325.6 138 271 3690.0 214 214 4672.9 63 426 2347.4 139 270 3703.7 215 214 4672.9 64 422 2369.7 140 269 3717.5 216 213 4694.8 65 418 2392.3 141 268 3731.3 217 212 4717.0 66 414 2415.5 142 267 3745.3 218 212 4717.0 67 410 2439.0 143 266 3759.4 219 211 4739.3 68 406 2463.1 144 265 3773.6 220 211 4739.3 69 403 2481.4 145 264 3787.9 221 210 4761.9 70 399 2506.3 146 263 3802.3 222 210 4761.9 71 396 2525.3 147 262 3816.8 223 209 4784.7 72 393 2544.5 148 261 3831.4 224 209 4784.7 73 389 2570.7 149 260 3846.2 225 208 4807.7 74 386 2590.7 150 259 3861.0 75 383 2611.0 151 258 3876.0

Time Between

Steps (µs)

Velocity

(µSteps/s)

Velocity Position

Time Between

Steps (µs)

Velocity

(µSteps/s)

Velocity Position

Time Between

Steps (µs)

(µSteps/s)

Velocity

INTERNAL CLOCK CALIBRATION

Timing-related functions on the 33970 (e.g., pointer velocities, acceleration, and Return To Zero Pointer speeds) depend upon a precise, consistent time reference to control the pointer accurately and reliably. Generating accurate time references on an integrated circuit can be accomplished; however, they tend to be costly due to the large amount of die

33970

area required for trim pads and the associated trim procedure. One possibility is an externally generated clock signal; however, this requires a dedicated pin on the device and controller. Another expensive approach would require the use of an additional crystal or resonator.

The internal clock in the 33970 is temperature

independent and area efficient; however, it can vary up to 70

Analog Integrated Circuit Device Data

26 Freescale Semiconductor

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

percent due to process variation. Using the existing SPI inputs and the precision timing reference already available to the microcontroller, the 33970 allows clock calibration to within ±10 percent.

Calibrating the internal 1.0 MHz clock is initiated by writing a logic [1] to PECCR bit PE3 (see Figure 10, page 27). The

8.0 µs calibration pulse that is then provided by the controller will ideally result in an internal 33970 clock speed of 1.0

MHz. The pulse is sent on the CS pin immediately after the SPI word is sent. No other SPI lines should be toggled. At the moment the

CS pin transitions from logic [1] to logic [0], an internal 7-bit counter counts the number of cycles of an internal 8.0

MHz clock. The counter stops when the CS pin

transitions from logic [0] to logic [1]. The value in the counter

D15

SCLK

PECCR Command

Figure 10. Gauge Enable and Clock Calibration Exa m pl e

Some applications may require a guaranteed maximum pointer velocity and acceleration. Guaranteeing these maximums requires nominal internal clock frequency falls below 1.0 will always be below 1.0

MHz. The frequency range of the calibrated clock

MHz if PECCR bit PE4 is logic [0]

prior to initiating a calibration command, followed by an

8.0 µs reference pulse. The frequency will be centered at

MHz if bit D4 is logic [1].

1.0

The 33970 can be fooled into calibrating faster or slower than the optimal frequency by sending a calibration pulse longer or shorter than the intended 8.0 µs. As long as the count remains between 4 and 15, there will be no clock calibration flag. For applications requiring a slower calibrated

— e.g., a motor designed with a gear ratio of 120:1

clock

microsteps/deg) — the user will have to provide a longer

(8 calibration pulse. The device allows a SPI-selectable slowing of the internal oscillator, using the PECCR command, so that the calibration divisor safely falls within the 4-to-15 range when calibrating with a longer time reference. For example, for the 120:1 motor, the pulse would be 12

µs. The result of this slower calibration results in the

8.0

µs instead of

longer step times necessary to generate pointer movements

represents the number of cycles of the 8.0

MHz clock

occurring in the 8.0 µs window; it should range from 32 to

119. An offset is added to this number to help center or skew the calibrated result to generate a desired maximum or nominal frequency. The modified counter value is truncated

bits to generate the calibration divisor, which should

by 4 range from 4 to 15. The 8.0 calibration divisor, resulting in a calibrated 1.0

MHz clock is divided by the

MHz clock. If the calibration divisor lies outside the range of 4 to 15, the 33970 flags the CAL bit of the status bits, indicating the calibration procedure was not successful. A clock calibration is allowed only if the gauges are disabled or the pointers are not moving, as indicated by status bits MOV1 and MOV0.

s Calibration Pulse

8.0

meeting acceleration and velocity requirements. The resolution of the pointer positioning decreases from

0.083

deg/microstep (180:1) to 0.125 deg/microstep (120:1).

The pointer sweep range increases from approximately

degrees to over 500 degrees.

340

Note Be aware that a fast calibration could result in violations of the motor acceleration and velocity maximums, resulting in missed steps.

POINTER DECELERATION

Constant acceleration and deceleration of the pointer produces relatively choppy movements when compared to those of an air core gauge. Air core behavior can be simulated with appropriate ramp modification during deceleration. This shaping can be accomplished by adding repetitive steps at several of the last step values as the pointer decelerates. The default movement in the 33970 uses this ramp modification feature. An example is shown in

Figure 11. If the maximum acceleration and deceleration of

the pointer is desired, the repetitive steps can be disabled by writing logic

[1] to the PECCR bit PE5.

33970

Analog Integrated Circuit Device Data Freescale Semiconductor 27

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

VELOCITY

Accelerat

n=0

11 10 9

HOLDCNT =2

STEPS

Figure 11. Deceleration Ramp

RETURN TO ZERO CALIBRATION

Many step motor applications require that the IC detect when the motor is stalled after commanded to return to the zero position for calibration purposes. The stalling occurs when the pointer hits the end stop on the gauge bezel, which is usually at the zero position. It is important that when the pointer reaches the end stop it immediately stops without bouncing away.

The 33970 device provides the ability to automatically and independently return each of the two pointers to the zero position via the RTZR and RTZCR SPI commands. An automatic RTZ is initiated using the RZ0, RZ1, and RZ2 bits. Unconditional RTZ movement is initiated using the RZ0, RZ2, and RZ4 bits. During an RTZ event, all commands related to the gauge being returned are ignored until the pointer has successfully zeroed or the RTZR bit RZ1 is written to disable the event. Once an RTZ event is initiated, the device reports back via the SO pin that an RTZ is underway.

The RTZCR command is used to set the RTZ pointer speed, choose an appropriate blanking time, and preload the integration accumulator with an appropriate offset. On reaching the end stop, the device reports back to the microcontroller via the status message that the RTZ was successful. The RTZ automatically disables, allowing other

commands to be valid. In the event the master determines an RTZ sequence is not working properly (i.e., the RTZ taking too long), it can disable the command via the RTZR bit RZ1.

RTZCR bits RC10:RC5 are written to preload the accumulator with a predetermined value that will assure an accurate pointer stall detection. This preloaded value is determined during application development by disabling the automatic shutdown feature of the device with the RTZR bits RZ4 and RZ2. This operating mode allows the master to monitor the RTZ event, using the accumulator information available via the SO if the device is configured to provide the RTZ Accumulator Status. The unconditional RTZ event can be turned OFF using the RTZR bit RZ1.

If the Position 0 location bit is in the default logic [0] mode, then during an RTZ event the pointer is returned counterclockwise (CCW) using full steps at a constant speed determined by the RTZCR RC3:RC0 and RC12:RC11 bits during RTZ configuration (see

Figure 12). Full steps are used

during an RTZ so that only one coil of the motor is being driven at any time. The coil not being driven is used to determine if the pointer is moving. If the pointer is moving, the EMF signal that is present in the non-driven coil is processed by integrating the signal present on the opened pin of the coil while essentially grounding the other end.

33970

Analog Integrated Circuit Device Data

28 Freescale Semiconductor

MAX

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

COIL

MAX

01 2 30

Figure 12. Full Steps Counterclockwise

The IC automatically prepares the non-driven coil at each step, waits for a predetermined blanking time, then processes the signal for the duration of the full step. When the pointer reaches the stop and no longer moves, the dissipating flux is detected. The processed results are placed in the RTZ accumulator, then compared to a decision threshold. If the signal exceeds the decision threshold, the pointer is assumed to be moving. If the threshold value is not exceeded, the drive sequence is stopped if RTZR bit RZ4 is

[0]. If bit RZ4 is logic [1], the RTZ movement will

logic continue indefinitely until the RTZR bit RZ1 is used to stop the RTZ event.

A pointer that is not on a full step location or that is in magnetic alignment prior to the RTZ event may cause a false RTZ detection. More specifically, an RTZ event beginning from a non-full step position may result in an abbreviated integration value potentially interpreted as a stalled pointer. Advancing the pointer by at least 12 microsteps clockwise (if PE7 = 0) to the nearest full step position (e.g., 0, 6, 12, 18, 24, etc.) prior to initiating an RTZ ensures the magnetic fields line up and increases the chances of a successful pointer stall detection. It is important that the pointer be in a static, or commanded, position before starting the RTZ event. Because the time duration and the number of steps the pointer moves prior to reaching the commanded position can vary depending upon its status at the time a position change is communicated, the master should assure sufficient elapsed time prior to starting an RTZ. If an RTZ is desired after first enabling the outputs or after forcing a reset of the device, the pointer should first be commanded to move 12 microsteps clockwise to the nearest full step location. Because the pointer was in a static position at default, the

SINE

COSINE

master could determine the number of microsteps the device has taken by monitoring and counting the MOV0. MOV1 device status bit transitions to confirm the pointer is again in a static position. Alternatively, the user could monitor the device status bits CMD1 and CMD2.

Only one gauge at a time can be returned to the zero position. The gauge not returning to zero can continue to be controlled. An RTZ should not begin until the gauge to be calibrated is at a static position and its pointer is at a full step position. An attempt to calibrate a gauge while the other is in the process of an RTZ event is ignored by the device. In most applications of the RTZR command, it is possible to avoid a visually obvious sequential calibration by first bringing the pointers back close to their previous zero positions, then recalibrating them sequentially.

After completion of an RTZ, the 33970 automatically assigns the zero-step position to the full step position at the end-stop location. Because the actual zero position could lie anywhere within the full step where the zero was detected, the assigned zero position could be within a window of ±0.5 degree. An RTZ can be used to detect stall, even if the pointer already rests on the end stop when an RTZ sequence is initiated. However, it is recommended the pointer be advanced by at least 12

microsteps to the nearest full step

prior to initiating the RTZ.

RTZ OUTPUT

During an RTZ event the non-driven coil is analyzed to determine the state of the motor. The 33970 multiplexes the coil voltages and provides the signal from the non-driven coil to the RTZ pin.

33970

Analog Integrated Circuit Device Data Freescale Semiconductor 29

FUNCTIONAL DEVICE OPERATION

LOGIC COMMANDS AND REGISTERS

DEFAULT MODE

Default mode refers to the state of the 33970 after an internal or external reset prior to SPI communication. An internal reset occurs during V

power-up or if V

PWR

falls below 4.0 V. An external reset is initiated by the RST pin driven to a logic

[0]. With the exception of the RTZCR full step time, all of the specific pin functions and internal registers will operate as though all of the addressable configuration register bits were set to logic

[0]. This means, for example, all of the outputs will be disabled after a power-up or external reset, and SO flag ST6 is set, indicating an undervoltage event. Anytime an external reset is exerted and the default is restored, all configuration parameters (e.g., clock calibration, maximum speed, RTZ parameters, etc.) are lost and must be reloaded.

FAULT LOGIC REQUIREMENTS

The 33970 device indicates each of the following faults as

they occur:

• Overtemperature fault

• Undervoltage V

• Overvoltage V

PWR

• Clock out of spec These fault bits remain enabled until they are clocked out

of the SO pin with a valid SPI message.

Overcurrent faults are not reported directly; however, it is likely an overcurrent condition will become a thermal issue and be reported.

OVERTEMPERATURE FAULT REQUIREMENTS

The 33970 incorporates overtemperature protection circuitry, which shuts off the affected gauge driver when excessive temperatures are detected. In the event of a thermal overload, the affected gauge driver is automatically disabled. The overtemperature fault is flagged via the OT0 and/or OT1 device status bits. The indicating flag continues to be set until the affected gauge is successfully re-enabled,

provided the junction temperature has fallen to a temperature below the hysteresis level.

OVERVOLTAGE FAULT REQUIREMENTS

The device is capable of surviving V the maximum specified in Table 2. V an Overvoltage Shutdown condition can result in uncertain pointer positions. Therefore, the pointer position should be re-calibrated. The master will be notified of an overvoltage event via the SO pin if the device status is selected. Overvoltage detection and notification occurs regard l ess of whether the gauge(s) are enabled or disabled.

voltages within

PWR

levels resulting in

PWR

OVERCURRENT FAULT REQUIREMENTS

Output currents are limited to safe levels allowing the device to rely on thermal shutdown to protect itself.

UNDERVOLTAGE FAULT REQUIREMENTS

Undervoltage V pointer positions. Therefore, the internal clock and the pointer position may require re-calibration. The state machine continues with V the coil voltages may be clipped. The master can be notified of an undervoltage event via the SO pin. Undervoltage detection and notification are disabled if both outputs are disabled.

conditions may result in uncertain

PWR

voltage levels as low as 4.0 V; however,

PWR

RESET (SLEEP MODE)

The device can reset internally or externally. If the VDD level falls below the V Characteristics table under POWER INPUT, page 5), the device resets and powers up in the Default mode. Similarly,

RST pin is driven to a logic [0], the device resets to its

If the default state. The device consumes the least amount of current (IDD and I

PWR

also referred to as the Sleep mode.

level (refer to the Static Electrical

DDUV

) when the RST pin is logic 0]. This is

33970

Analog Integrated Circuit Device Data

30 Freescale Semiconductor

TYPICAL APPLICATIONS

INTRODUCTION

TYPICAL APPLICATIONS

INTRODUCTION

The 33970 is an extremely versatile device used in a variety of applications. Table 22 provides a step-by-step example of configuring and using many of the features designed into the IC.

Table 22. 33970 Setup, Configuration, and Usage Example

Step Command Description

1 PECCR

2 RTZCR

(a) Enable Gauges

- Bit PE0: Gauge 0

- Bit PE1: Gauge 1

(b) Clock Calibration

- Bit PE3: Enables Calibration Procedure

- Bit PE4: Set clock f = 1.0 MHz maximum or nominal (c) Send 8.0 µs pulse on CS to calibrate 1.0 MHz clock (a) Set RTZ Full Step Time

- Bits RC3:RC0 (b) Set RTZ Blanking Time

- Bit RC4 (c) Preload RTZ Accumulator

- Bits RC12:RC11 and RC10:RC5

This example is intended to give a generic overview how the device could be used. Further, it is intended to familiarize users with some of its capabilities.

Reference Table

and or Figure

Table 7 (page 14),

Figure 10 (page 27)

Table 12 (page 17),

Table 13 (page 18)

Table 14 (page 18)

3 POS0R 4 POS1R

5 PECCR

6 RTZ

(d) Check SO for an Out-of-Range Clock Calibration

- Is bit CAL logic [1]? If so, then repeat Steps 1 and 2 (a) Move pointer to position 12 prior to RTZ (a) Move pointer to position 12 prior to RTZ (b) Check SO to see if Gauge 0 has moved

- Is bit MOV0 (OD4) logic [1]? If so then the Gauge 0 has moved to the first microstep (a) Send null command to see if gauges have moved

- Bit PE12 (b) Check SO to see if Gauge 0 (Gauge 1) has moved

- Is bit MOV0 (OD4) (MOV1 (OD5)) logic [1]? If so, then Gauge 0 (Gauge 1) moved

another microstep. Keep track of movement and if 12 steps are finished and both gauges are at a static position, then RTZ. Otherwise, repeat steps (a) and (b)

- Bit CMD0 (OD10) (CMD1 (OD11)) could also be monitored to determine that the

pointer is static

(a) Return one gauge at a time to the zero stop using RTZ command

- Bit RZ0 selects the gauge

- Bit RZ1 is used to enable or disable an RTZ

- Bits RZ2 is used to select the direction (along with PE7) (b) Select the RTZ accumulator bits to clock out on the SO bits using bits PE11:PE10. These

will be used if characterizing the RTZ.

Table 7 (page 14),

Table 15 (page 19)

Table 9 (page 16)

Table 10 (page 16)

Table 7 (page 14),

Table 15 (page 19)

Table 7 (page 14)

Table 7 (page 14),

Table 15 (page 19)

Table 11 (page 16)

Table 7 (page 14),

Table 16 (page 20)

33970

Analog Integrated Circuit Device Data Freescale Semiconductor 31

TYPICAL APPLICATIONS

INTRODUCTION

Table 22. 33970 Setup, Configuration, and Usage Example (continued)

Step Command Description

7 PECCR

(a) Check the Status of the RTZ by sending the null command to monitor SO bit RTZ0, RTZ1

of Device Status SO

- Bit PE12 is the null command (b) Is RTZ0 (OD2) logic [0]? If not, Gauge 0 still returning and null command should be

resent.

8 RTZ

(a) Return the other gauge to the zero stop. If the second gauge is driving a different pointer

than the first, a new RTZCR command may be required to change the Full Step time.

9 PECCR

(a) Check the Status of the RTZ by sending the null command to monitor SO, bit RTZ1 (OD3)

- Bit PE12 is the null command (b) Is RTZ1 (OD3) logic [0]? If not, Gauge 1 still returning and null command should be

resent.

10 VELR

(a) Change the maximum velocity of the gauge

- Bits V8:V9 determine which gauge(s) will change the maximum velocity

- Bits V7:V0 determine the maximum velocity position from Table 21, Velocity Table

11 POS0R

(a) Position Gauge 0 pointer

- Bits P011:P00: Desired Pointer Position (b) Check SO for Out-of-Range V

PWR

- Bit OVUV (OD6) logic [1]? If so, use UV (OD8) and OV (OD9) to decide whether to

RTZ after valid V

PWR

Reference Table

and or Figure

Table 7 (page 14),

Table 15 (page 19)

Table 11 (page 16)

Table 7 (page 14),

Table 15 (page 19)

Table 7 (page 15),

Table 21 (page 24)

Table 9 (page 16),

Table 21 (page 24)

12 POS1R

13 POS0R

14 POS1R

- Bit OT0 logic [1]? If so, enable driver again. If OT0 continues to indicate

overtemperature, shut down Gauge 0

- If RTZ0 returns to normal, re-establish the zero reference by RTZ command (a) Position Gauge 1 pointer

- Bits P1 11:P1 0: Desired Pointer Position (b) Check SO for Out-of-Range V

PWR

- Bit OVUV logic [1]? If so, use UV (OD8) and OV (OD9) to decided whether to RTZ

after valid V

PWR

- Bit OT1 logic [1]? If so, enable driver again. If OT1 continues to indicate overtemperature,

shut down Gauge 1.

- If OT1 returns to normal, re-establish the zero reference by RTZ command (a) Return the pointers close to zero position using POS0R (b) Move pointer position at least 12 microsteps CW to the nearest full step prior to RTZ (c) Return the pointers close to zero position using POS1R (d) Move pointer position at least 12 microsteps CW to the nearest full step position prior to

RTZ

(e) Check SO to see if Gauge 0 has moved

- Bit MOV0 logic [1]? If so, Gauge 0 moved to the first microstep

Table 10 (page 16),

Table 21 (page 24)

Table 9 (page 16)

Table 10 (page 16)

Table 10 (page 16),

Table 15 (page 19)

33970

Analog Integrated Circuit Device Data

32 Freescale Semiconductor

Table 22. 33970 Setup, Configuration, and Usage Example (continued)

TYPICAL APPLICATIONS

INTRODUCTION

Step Command Description

15 PECCR

16 RTZ

17 PECCR

18 RTZ

19 PECCR

(f) Send null command to see if gauges have moved

- Bits PE12

(g) Check SO to see if Gauge 0 (Gauge 1) moved

- Bit MOV0 (MOV1) logic [1]? If so, Gauge 0 (Gauge 1) moved another microstep. Keep track of movement. If 12 steps are finished, and both gauges are at a static position, then RTZ. Otherwise repeat steps (a) and (b)

- Bit CMD0 (OD10) (CMD1 (OD1)) could also be monitored to determine that the pointer is static

(a) Return one gauge at a time to the zero stop using RTZ command

- Bit RZ0 selects the gauge

- Bit RZ1 is used to enable or disable an RTZ

- Bit RZ2 is used to select the direction (along with PE7)

(b) Select the RTZ accumulator bits clocking out on the SO bits using bits PE11:PE10. These

will be used if characterizing the RTZ

(a) Check the status of the RTZ by sending the null command to monitor SO bit RTZ0

- Bit PE12 is the null command (b) Is RTZ0 logic [0]? If not, Gauge 0 still returning and null command should be resent (c) Return the other gauge to the zero stop. If the second gauge is driving a different pointer

than the first, a new RTZCR command may be required to change the Full Step time

(a) Check the status of the RTZ by sending the null command to monitor SO bit RTZ1

- Bit PE12 is the null command

Reference Table

and or Figure

Table 7 (page 14),

Table 15 (page 19)

Table 7 (page 14),

Table 11 (page 16),

Table 16 (page 20)

Table 7 (page 14),

Table 15 (page 19)

Table 11 (page 16),

Table 14 (page 18)

Table 7 (page 14),

Table 15 (page 19)

20 PECCR

(b) Is RTZ1 logic [0]? If not, Gauge 1 still returning and null command should be resent (a) Disable both gauges and go to standby

- Bit PE0:PE1 are used to disable the gauges (b) Put the device to sleep

- RST pin is pulled to logic [0]

Table 11 (page 16)

Table 7 (page 14)

33970

Analog Integrated Circuit Device Data Freescale Semiconductor 33

PACKAGING

PACKAGE DIMENSIONS

PACKAGING

PACKAGE DIMENSIONS

For the most current package revision, visit www.freescale.com and perform a keyword search using the “98A” listed below.

DW SUFFIX

EG SUFFIX (Pb-FREE)

33970

24-PIN

PLASTIC PACKAGE

98ASB42344B

ISSUE F

Analog Integrated Circuit Device Data

34 Freescale Semiconductor

REVISION HISTORY

REVISION DATE DESCRIPTION OF CHANGES

2.0

3.0

8/2006

1/2007

• Implemented Revision History page

• Converted to Freescale format

• Corrected Symbol notation for Microstep Outp ut (M ea su red Across Coil Outputs)

SIN0,1, ± (COS0,1, ±) (refer to Table 1) and Output Flyback Clamp

• Added maximum pointer calculation on page 16

• Corrected detect threshold upper range from 4081 to 1009

• Changed internal clock variation from 35% to 70%

• Changed EMF to flux on page 28

• Added MCZ33970EG/R2 to the Ordering Information block

• Revised Internal Block Diagram to enhance readability

• Added parameter Peak Package Reflow Temperature During Reflow and notes

• Added ADC Gain

(4)

and

(5)

(10), (13)

• Made wording additions to Address 101 — Gauge Return to Zero Configuration Register

on page 17 and RC12:RC11 = M on page 18

• Added RTZ Accumulator (Typical) on page 21 and accompanying te xt

to Static Elecrtrical Characteristics table.

REVISION HISTORY

(10)

(4), (5)

on page 4

33970

Analog Integrated Circuit Device Data Freescale Semiconductor 35

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MC33970 Rev. 3.0 1/2007

Freescale 33970 Technical Data

Specifications and Main Features

Frequently Asked Questions

User Manual

Figure 1. 33970 Simplified Application Diagram

INTERNAL BLOCK DIAGRAM

Figure 2. 33970 Simplified Internal Block Diagram

PIN CONNECTIONS

Figure 3. 33970 Pin Connections

Table 1. 33970 Pin Definitions

ELECTRICAL CHARACTERISTICS

Table 2. Maximum Ratings

Table 3. Static Electrical Characteristics

Table 4. Dynamic Electrical Characteristics

Figure 4. Input Timing Switching Characteristics

Figure 5. Valid Data Delay Time and Valid Time Waveforms

FUNCTIONAL DESCRIPTION

FUNCTIONAL DEVICE OPERATION

Table 5. Data Transfer Timing

Figure 6. Single 16-Bit Word SPI Communication

Figure 7. Multiple 16-Bit Word SPI Communication

Table 6. Module Memory Map

Table 7. Power, Enable, Calibration, and Configuration Register (PECCR)

Table 8. Maximum Velocity Register (VELR)

Table 9. Gauge 0 Position Register (POS0R)

Table 10. Gauge 1 Position Register (POS1R)

Table 11. Return to Zero Register (RTZR)

Table 12. RTZCR SI Register Assignment

Table 13. RTZCR Full Step Time

Table 14. RTZCR Accumulator Offset

Table 15. Device Status Output Register

Table 16. RTZ Accumulator Status Output Register

Figure 8. RTZ Accumulator (Typical)

Table 17. Gauge 0 Pointer Position Status Output Register

Table 18. Gauge 1 Pointer Position Status Output Register

Table 19. Gauge 0 and 1 Pointer Velocity Status Output Register

Figure 9. Clockwise Microsteps

Table 20. Coil Step Value

Table 21. Velocity Table

Figure 10. Gauge Enable and Clock Calibration Exa m pl e

Figure 11. Deceleration Ramp

Figure 12. Full Steps Counterclockwise

TYPICAL APPLICATIONS

Table 22. 33970 Setup, Configuration, and Usage Example

PACKAGING

REVISION HISTORY