Datasheet AD5063 Datasheet (ANALOG DEVICES)

Page 1
Fully Accurate 16-Bit V
V
V
A
nanoDAC
OUT
SPI Interface 2.7 V to 5.5 V in an MSOP

FEATURES

Single 16-bit DAC, 1 LSB INL Power-on reset to midscale Guaranteed monotonic by design 3 power-down functions Low power serial interface with Schmitt-triggered inputs 10-lead MSOP, low power Fast settling time of 1 μs maximum (AD5063-1 model)
2.7 V to 5.5 V power supply Low glitch on power-up Unbuffered voltage capable of driving 60 kΩ load
interrupt facility
SYNC

APPLICATIONS

Process control Data acquisition systems Portable battery-powered instruments Digital gain and offset adjustment Programmable voltage and current sources Programmable attenuators

GENERAL DESCRIPTION

The AD5063, a member of ADI’s nanoDAC™ family, is a low power, single 16-bit, unbuffered voltage-output DAC that operates from a single 2.7 V to 5 V supply. The part offers a relative accuracy specification of ±1 LSB, and operation is guaranteed monotonic with a ±1 LSB DNL specification. The AD5063 comes with on-board resistors in a 10-lead MSOP, allowing bipolar signals to be generated with an output amplifier. The part uses a versatile 3-wire serial interface that operates at clock rates up to 30 MHz and that is compatible with standard SPI®, QSPI™, MICROWIRE™, and DSP interface standards. The reference for the AD5063 is supplied from an external V A reference buffer is also provided on-chip. The part incor­porates a power-on reset circuit that ensures the DAC output powers up to midscale and remains there until a valid write to the device takes place. The part contains a power-down feature
REF
pin.
AD5063

FUNCTIONAL BLOCK DIAGRAM

AD5063
DD
R
FB
INV
V
OUT
GND
RESISTOR NETWORK
04766-001
REF
POWER-ON
RESET
DAC
REGISTER
INPUT
CONTROL
LOGIC
SCLK DIN
SYNC DACGND
BUF
REF(+)
DAC
POWER-DOWN
CONTROL LO GIC
Figure 1.
Table 1. Related Devices
Part No. Description
AD5061
2.7 V to 5.5 V, 16-bit nanoDAC D/A, 4 LSBs INL, SOT-23.
AD5062
2.7 V to 5.5 V, 16-bit nanoDAC D/A, 1 LSB INL, SOT-23.
AD5040/AD5060
2.7 V to 5.5 V, 14-/16-bit nanoDAC D/A, 1 LSB INL, SOT-23.
that reduces the current consumption of the device to typically 300 nA at 5 V and provides software-selectable output loads while in power-down mode. The part is put into power-down mode via the serial interface. Total unadjusted error for the part is <1 mV.
This part exhibits very low glitch on power-up.

PRODUCT HIGHLIGHTS

Available in 10-lead MSOP.
16-bit accurate, 1 LSB INL.
Low glitch on power-up.
High speed serial interface with clock speeds up to 30 MHz.
Three power-down modes available to the user.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2005–2009 Analog Devices, Inc. All rights reserved.
Page 2
AD5063

TABLE OF CONTENTS

Features .............................................................................................. 1
Serial Interface ............................................................................ 13
Applications ....................................................................................... 1
Functional Block Diagram .............................................................. 1
General Description ......................................................................... 1
Product Highlights ........................................................................... 1
Revision History ............................................................................... 2
Specifications ..................................................................................... 3
Timing Characteristics ................................................................ 5
Absolute Maximum Ratings ............................................................ 6
ESD Caution .................................................................................. 6
Pin Configuration and Function Descriptions ............................. 7
Typical Performance Characteristics ............................................. 8
Terminology .................................................................................... 12
Theory of Operation ...................................................................... 13
DAC Architecture ....................................................................... 13
Reference Buffer ......................................................................... 13
Input Shift Register .................................................................... 13
SYNC
Interrupt .......................................................................... 13
Power-On to Midscale ............................................................... 14
Software Reset ............................................................................. 14
Power-Down Modes .................................................................. 14
Microprocessor Interfacing ....................................................... 14
Applications ..................................................................................... 16
Choosing a Reference for the AD5063 .................................... 16
Bipolar Operation Using the AD5063 ..................................... 16
Using the AD5063
with a Galvanically Isolated Interface Chip ............................ 17
Power Supply Bypassing and Grounding ................................ 17
Outline Dimensions ....................................................................... 18
Ordering Guide .......................................................................... 18

REVISION HISTORY

8/09—Rev. B to Rev. C
Changes to Features Section............................................................ 1
Changes to Output Voltage Settling Time Parameter, Table 2 ... 3
Updated Outline Dimensions ....................................................... 18
Changes to Ordering Guide .......................................................... 18
3/06—Rev. A to Rev. B
Updated Format .................................................................. Universal
Change to Features ........................................................................... 1
Change to Figure 1 ........................................................................... 1
Changes to Specifications ................................................................ 3
Change to Absolute Maximum Ratings ......................................... 6
Change to Reference Buffer Section ............................................ 13
Change to Serial Interface Section ............................................... 13
Change to Table 6 ........................................................................... 14
Change to Bipolar Operation Using the AD5063 Section ........ 16
7/05—Rev. 0 to Rev. A
Changes to Galvanically Isolated Chip Section .......................... 17
Changes to Figure 38 ...................................................................... 17
4/05—Revision 0: Initial Version
Rev. C | Page 2 of 20
Page 3
AD5063

SPECIFICATIONS

VDD = 2.7 V to 5.5 V, V
Table 2.
B Version1 Parameter Min Typ Max Unit Test Conditions/Comments
STATIC PERFORMANCE
Resolution 16 Bits Relative Accuracy (INL) ±0.5 ±1 LSB −40°C to + 85°C, B grade over all codes Total Unadjusted Error (TUE) ±500 ±800 μV Differential Nonlinearity (DNL) ±0.5 ±1 LSB Guaranteed monotonic Gain Error ±0.01 ±0.02 % FSR TA = −40°C to +85°C Gain Error Temperature Coefficient 1 ppm FSR/°C Zero-Code Error ±0.05 ±0.1 mV
Zero-Code Error Temperature Coefficient 0.05 μV/°C Offset Error ±0.05 ±0.1 mV TA = −40°C to +85°C Offset Error Temperature Coefficient 0.5 μV/°C Full-Scale Error ±500 ±800 μV
Bipolar Resistor Matching 1 Ω/Ω RFB/R Bipolar Zero Offset Error ±8 ±16 LSB Bipolar Zero Temperature Coefficient ±0.5 ppm FSR/°C Bipolar Gain Error ±16 ±32 LSB
OUTPUT CHARACTERISTICS2
Output Voltage Range 0 V
−V Output Voltage Settling Time3 ¼ scale to ¾ scale code transition to ±1 LSB
AD5063BRMZ 4 μs
AD5063BRMZ-1 1 μs VDD = 4.5 V to 5.5 V 4 μs VDD = 2.7 V to 5.5 V Output Noise Spectral Density 64 nV/√Hz DAC code = midscale, 1 kHz Output Voltage Noise 6 μV p-p
Digital-to-Analog Glitch Impulse 2 nV-s 1 LSB change around major carry Digital Feedthrough 0.002 nV-s DC Output Impedance (Normal) 8 Output impedance tolerance ±10% DC Output Impedance (Power-Down)
(Output Connected to 1 kΩ Network) 1 Output impedance tolerance ±400 Ω (Output Connected to 10 kΩ Network) 100 Output impedance tolerance ±20 kΩ
REFERENCE INPUT/OUPUT
V
Input Range 2 V
REF
Input Current (Power-Down) ±1 μA Zero-scale loaded Input Current (Normal) ±1 μA DC Input Impedance 1 Bipolar/unipolar operation
LOGIC INPUTS
Input Current4 ±1 ±2 μA Input Low Voltage, VIL 0.8 V VDD = 4.5 V to 5.5 V
0.8 VDD = 2.7 V to 3.6 V Input High Voltage, VIH 2.0 V VDD = 2.7 V to 5.5 V
1.8 VDD = 2.7 V to 3.6 V Pin Capacitance 4 pF
= 4.096 V @ VDD = 5.0 V, RL = unloaded, CL = unloaded to GND; T
REF
V Unipolar operation
REF
V
REF
V Bipolar operation
REF
− 50 mV
DD
MIN
to T
, unless otherwise noted.
MAX
All 0s loaded to DAC register,
= −40°C to +85°C
T
A
All 1s loaded to DAC register, TA = −40°C to +85°C
, RFB = R
INV
= 30 kΩ typically
INV
DAC code = midscale, 0.1 Hz to 10 Hz bandwidth
Rev. C | Page 3 of 20
Page 4
AD5063
B Version1 Parameter Min Typ Max Unit Test Conditions/Comments
POWER REQUIREMENTS
VDD 2.7 5.5 V All digital inputs at 0 V or VDD IDD (Normal Mode) DAC active and excluding load current VDD = 4.5 V to 5.5 V 0.65 0.7 mA
VDD = 2.7 V to 3.6 V 0.5 mA VIH = VDD and VIL = GND, VDD = 3 V IDD (All Power-Down Modes)
VDD = 4.5 V to 5.5 V 1 μA VIH = VDD and VIL = GND VDD = 2.7 V to 3.6 V 1 μA VIH = VDD and VIL = GND
Power Supply Rejection Ratio (PSRR) 0.5 LSB ∆VDD ± 10%, VDD = 5 V, unloaded
1
Temperature ranges for the B version: −40°C to +85°C, typical at +25°C, functional to +125°C.
2
Guaranteed by design and characterization, not production tested.
3
See the Ordering Guide.
4
Total current flowing into all pins.
= VDD and VIL = GND, VDD = 5 V,
V
IN
= 4.096 V, code = midscale
V
REF
Rev. C | Page 4 of 20
Page 5
AD5063

TIMING CHARACTERISTICS

VDD = 2.7 V to 5.5 V; all specifications T
Table 3.
Parameter Limit1 Unit Test Conditions/Comments
2
t
33 ns min SCLK cycle time
1
t2 5 ns min SCLK high time t3 3 ns min SCLK low time t4 10 ns min t5 3 ns min Data setup time t6 2 ns min Data hold time t7 0 ns min
t8 12 ns min t9 9 ns min
1
All input signals are specified with tR = tF = 1 ns/V (10% to 90% of VDD) and timed from a voltage level of (VIL + VIH)/2.
2
Maximum SCLK frequency is 30 MHz.
SCLK
SYNC
DIN
t
8
to T
MIN
t
4
, unless otherwise noted.
MAX
to SCLK falling edge setup time
SYNC
SCLK falling edge to SYNC Minimum SYNC
rising edge to next SCLK fall ignore
SYNC
t
t
2
1
t
3
t
t
5
high time
6
D0D1D2D22D23
rising edge
t
9
t
7
D23 D22
04766-002
Figure 2. Timing Diagram
Rev. C | Page 5 of 20
Page 6
AD5063

ABSOLUTE MAXIMUM RATINGS

Table 4.
Parameter Rating
VDD to GND −0.3 V to +7.0 V Digital Input Voltage to GND −0.3 V to VDD + 0.3 V V
to GND −0.3 V to VDD + 0.3 V
OUT
V
to GND −0.3 V to VDD + 0.3 V
REF
INV to GND −0.3 V to VDD + 0.3 V RFB to GND +7 V to −7 V Operating Temperature Range
Industrial (B Version) −40°C to + 85°C1 Storage Temperature Range −65°C to +150°C Maximum Junction Temperature 150°C MSOP Package
Power Dissipation (TJ max − TA)/θJA
θJA Thermal Impedance 206°C/W
θJc Thermal Impedance 44°C/W Reflow Soldering (Pb-Free)
Peak Temperature 260(0/−5)°C
Time at Peak Temperature 10 sec to 40 sec ESD 1.5 kV
1
Temperature range for this device is 40°C to +85°C; however, the device is
still operational at 125°C.
Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
This device is a high performance integrated circuit with an ESD rating of <2 kV, and it is ESD sensitive. Proper precautions should be taken for handling and assembly.

ESD CAUTION

ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although this product features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.
Rev. C | Page 6 of 20
Page 7
AD5063

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

110
DIN
V
29
DD
AD5063
38
V
V
TOP VIEW
REF
(Not to Scale)
47
OUT
56
INV
Figure 3. Pin Configuration
Table 5. Pin Function Descriptions
Pin No. Mnemonic Description
1 DIN
Serial Data Input. This device has a 24-bit shift register. Data is clocked into the register on the falling edge of the
serial clock input. 2 VDD Power Supply Input. These parts can be operated from 2.7 V to 5.5 V, and VDD should be decoupled to GND. 3 V 4 V 5 INV
Reference Voltage Input.
REF
Analog Output Voltage from DAC.
OUT
Connected to the Internal Scaling Resistors of the DAC. Connect the INV pin to the external op amp’s inverting
input in bipolar mode. 6 RFB Feedback Resistor. In bipolar mode, connect this pin to the external op amp circuit. 7 AGND Ground Reference Point for Analog Circuitry. 8 DACGND Ground Input to the DAC. 9
Level-Triggered Control Input (Active Low). This is the frame synchronization signal for the input data. When
SYNC
SYNC
goes low, it enables the input shift register, and data is then transferred in on the falling edges of the
following clocks. The DAC is updated following the 24
10 SCLK
which case the rising edge of SYNC
Serial Clock Input. Data is clocked into the input shift register on the falling edge of the serial clock input. Data
acts as an interrupt, and the write sequence is ignored by the DAC.
can be transferred at rates of up to 30 MHz.
SCLK
SYNC
DACGND
AGND
R
FB
04766-003
th
clock cycle unless SYNC is taken high before this edge, in
Rev. C | Page 7 of 20
Page 8
AD5063

TYPICAL PERFORMANCE CHARACTERISTICS

1.4 TA = 25°C
1.2
V
= 5V V
DD
1.0
0.8
0.6
0.4
0.2
0
INL ERROR (LSB)
–0.2
–0.4
–0.6
–0.8
–1.0
0 10000 20000 30000 40000 50000 60000 70000
= 4.096V
REF
04766-047
DAC CODE
Figure 4. INL Error vs. DAC Code Figure 7. DNL Error vs. DAC Code
1.0 TA = 25°C
V
= 5V V
REF
= 4.096V
DAC CODE
DD
0.8
0.6
0.4
0.2
0
–0.2
DNL ERRO R (LSB)
–0.4
–0.6
–0.8
–1.0
0 10000 20000 30000 40000 50000 60000 70000
04766-046
0.10 TA = 25°C
V
= 5V V
REF
= 4.096V
DAC CODE
DD
0.08
0.06
0.04
0.02
0
–0.02
TUE ERROR (mV)
–0.04
–0.06
–0.08
–0.10
0 10000 20000 30000 40000 50000 60000 70000
Figure 5. TUE Error vs. DAC Code
1.2 VDD = 5.5V V
V
= 2.7V V
1.0
DD
0.8
0.6
0.4
0.2
0
–0.2
INL ERROR (LSB)
–0.4
–0.6
–0.8
–1.0
–40 –20 0 20 40 60 80 100 120 140
= 4.096V
REF
= 2.0V
REF
TEMPERATURE (° C)
MAX INL @ VDD = 2.7V
MAX INL @ VDD = 5.5V
MIN INL @ VDD = 5.5V
MIN INL @ VDD = 2.7V
Figure 6. INL Error vs. Temperature
1.0 VDD = 5.5V V V
= 2.7V V
0.8
DD
0.6
0.4
0.2
0
–0.2
DNL ERROR (LSB)
–0.4
–0.6
–0.8
04766-048
–1.0
–40 –20 0 20 40 60 80 100 120 140
= 4.096V
REF
= 2.0V
REF
MIN DNL @ VDD = 2.7V
MIN DNL @ VDD = 5.5V
TEMPERATURE (° C)
MAX DNL @ VDD = 5.5V
MAX DNL @ VDD = 2.7V
04766-013
Figure 8. DNL Error vs. Temperature
1.0
VDD = 5.5V V V
= 2.7V V
0.8
DD
0.6
0.4
0.2
MIN TUE @ 5.5V
0
–0.2
TUE ERROR (LS B)
–0.4
–0.6
–0.8
04766-012
–1.0
MIN TUE @ 2. 7V
–40 –20 0 20 40 60 80 100 120 140
= 4.096V
REF
= 2.0V
REF
MAX TUE @ 2.7V MAX TUE @ 5.5V
TEMPERATURE ( °C)
04766-009
Figure 9. TUE Error vs. Temperature
Rev. C | Page 8 of 20
Page 9
AD5063
3
TA = 25°C
2
1
0
INL ERRO R (LSB)
–1
–2
–3
1
MAX INL @ VDD = 5.5V
MIN INL @ VDD = 5.5V
REFERENCE VO LTAGE (V)
Figure 10. INL Error vs. Reference Input Voltage
04766-004
62345
0.25 VDD = 5.5V V
V
= 2.7V V
0.20
DD
0.15
0.10
0.05
0
–0.05
OFFSET (mV)
–0.10
–0.15
–0.20
–0.25
–40 –20 0 20 40 60 80 100 120 140
= 4.096V
REF
= 2.0V
REF
TEMPERATURE ( °C)
MAX OFFSET @ VDD = 5.5V
MAX OFFSET @ VDD = 2.7V
Figure 13. Offset vs. Temperature
04766-007
1.0 TA = 25°C
0.8
0.6
0.4
0.2
0
–0.2
DNL ERRO R (LSB)
–0.4
–0.6
–0.8
–1.0
1
MAX DNL VDD = 5.5V
MIN DNL VDD = 5.5V
REFERENCE VO LTAGE (V)
Figure 11. DNL Error vs. Reference Input Voltage
0.10 TA = 25°C
0.08
0.06
–0.02
TUE ERROR (mV)
–0.04
–0.06
–0.08
–0.10
0.04
0.02
0
1
MAX TUE @ VDD = 5.5V
MIN TUE @ VDD = 5.5V
REFERENCE VO LTAGE (V)
Figure 12. TUE Error vs. Reference Input Voltage
1.0
0.9
0.8
0.7 VDD = 5.5V V
0.6
0.5 VDD = 3V V
0.4
0.3
SUPPLY CURRENT (mA)
0.2
0.1
04766-044
62345
0
–40 –20 0 20 40 60 80 100 120 140
= 4.096V
REF
= 2.7V
REF
TEMPERATURE (° C)
04766-041
Figure 14. Supply Current vs. Temperature
1.0 TA = 25°C
0.9
0.8
0.7
0.6
0.5
0.4
0.3
SUPPLY CURRENT (mA)
0.2
0.1
04766-005
62345
0
0 10000 20000 30000 40000 50000 60000 70000
VDD = 5.5V V
VDD = 3V V
REF
REF
DIGITAL INPUT CODE
= 4.096V
= 2.5V
04766-042
Figure 15. Supply Current vs. Digital Input Code
Rev. C | Page 9 of 20
Page 10
AD5063
1.0 TA = 25°C V
0.9
0.8
0.7
0.6
0.5
0.4
0.3
SUPPLY CURRENT (mA)
0.2
0.1
= 2.7V
REF
0
2.7 3.2 3.7 4.2 4.7 5.2 5.7 SUPPLY VOLTAGE (V)
Figure 16. Supply Current vs. Supply Voltage
CH3 = SCLK
CH2 = V
OUT
CH1 = TRIGGER
04766-043
CH1 2V/DIV CH2 2V/DIV CH3 2V TIME BASE = 5.00μs
04766-026
Figure 19. Exiting Power-Down Time to Midscale
24TH CLO CK FALLI NG
CH1 = SCLK
CH2 = V
OUT
CH2 50mV/DIV CH1 2V/DIV TIME BASE 400ns/DIV
Figure 17. Digital-to-Analog Glitch Impulse (See Figure 21)
300
VDD = 5V T
= 25°C
A
V
= 4.096V
REF
250
200
150
FULL SCALE
100
50
NOISE SPECT RAL DENSITY (n V/ Hz)
MIDSCALE
ZERO SCALE
VDD = 3V DAC = FULL SCALE V
= 2.7V
REF
T
= 25°C
A
04766-015
Y-AXIS = 2µV/DI V X-AXIS = 4sec/ DIV
04766-018
Figure 20. 0.1 Hz to 10 Hz Noise Plot
VDD = 5V
V
= 4.096V
REF
T
= 25°C
A
10ns/SAMPL E
AMPLITUDE (200µV/DIV )
0
100
1000 10000 100000 1000000
FREQUENCY ( Hz)
Figure 18. Output Noise Spectral Density
04766-011
Rev. C | Page 10 of 20
50 100 150 200 250 300 350 400 450 5000
SAMPLES
04766-017
Figure 21. Glitch Energy
Page 11
AD5063
0.010 VDD = 5.5V V
V
= 2.7V V
DD
0
–40 –20 0 20 40 60 80 100 120 140
–0.002
GAIN ERROR (%fsr)
–0.004
–0.006
–0.008
–0.010
0.008
0.006
0.004
0.002
Figure 22. Gain Error vs. Temperature
20
18
16
14
12
10
8
FREQUENCY
6
4
2
0
0.550
0.565
Figure 23. I
= 4.096V
REF
= 2.0V
REF
TEMPERATURE ( °C)
0.580
0.595
0.610
Histogram @ VDD = 5 V
DD
GAIN ERROR @ VDD = 5.5V
GAIN ERROR @ VDD = 2.7V
0.625
0.640
BIN
0.655
CH1 = V
DD
CH2 = V
OUT
VDD = 5V V
04766-010
RAMP RATE = 200µs T
= 25°C
A
CH1 2V/DIV CH2 1V/DIV TIME BASE = 100µs
REF
= 4.096V
04766-022
Figure 25. Hardware Power-Down Glitch
CH1 = SCLK
CH2 = SYNC
CH3 = V
OUT
04766-049
0.680 MORE
VDD = 5V V T
= 25°C
A
CH1 2V/DIV CH2 2V/DIV CH3 20mV/DIV CH4 2V/DIV TIME BASE 1µ s/DIV
REF
= 4.096V
CH4 = TRIGG ER
04766-020
Figure 26. Exiting Software Power-Down Glitch
35
30
25
20
15
FREQUENCY
10
5
0.535
04766-050
0.545
0
0.465
0.475
0.485
0.495
0.505
0.515
DD
0.525
= 3 V
BIN
Figure 24. IDD Histogram @ V
Rev. C | Page 11 of 20
Page 12
AD5063

TERMINOLOGY

Relative Accuracy
For the DAC, relative accuracy, or integral nonlinearity (INL), is a measure of the maximum deviation, in LSB, from a straight line passing through the endpoints of the DAC transfer function. A typical INL error vs. code plot is shown in Figure 4.
Differential Nonlinearity (DNL)
Differential nonlinearity is the difference between the measured change and the ideal 1 LSB change between any two adjacent codes. A specified differential nonlinearity of ±1 LSB maximum ensures monotonicity. This DAC is guaranteed monotonic by design. A typical DNL error vs. code plot is shown in Figure 7.
Zero-Code Error
Zero-code error is a measure of the output error when zero code (0x0000) is loaded to the DAC register. Ideally, the output should be 0 V. The zero-code error is always positive in the AD5063 because the output of the DAC cannot go below 0 V. This is due to a combination of the offset errors in the DAC and output amplifier. Zero-code error is expressed in mV.
Full-Scale Error
Full-scale error is a measure of the output error when full-scale code (0xFFFF) is loaded to the DAC register. Ideally, the output should be V of the full-scale range.
Gain Error
Gain error is a measure of the span error of the DAC. It is the deviation in slope of the DAC transfer characteristic from ideal, expressed as a percentage of the full-scale range.
− 1 LSB. Full-scale error is expressed as a percentage
DD
Tot a l U n ad ju s te d E rr o r ( TU E )
Total unadjusted error is a measure of the output error, taking all the various errors into account. A typical TUE vs. code plot is shown in Figure 5.
Zero-Code Error Drift
Zero-code error drift is a measure of the change in zero-code error with a change in temperature. It is expressed in μV/°C.
Gain Error Drift
Gain error drift is a measure of the change in gain error with a change in temperature. It is expressed in (ppm of full-scale range)/°C.
Digital-to-Analog Glitch Impulse
Digital-to-analog glitch impulse is the impulse injected into the analog output when the input code in the DAC register changes state. It is normally specified as the area of the glitch in nV-s and is measured when the digital input code is changed by 1 LSB at the major carry transition. See Figure 17 and Figure 21. Figure 17 shows the glitch generated following completion of the calibration routine; Figure 21 zooms in on this glitch.
Digital Feedthrough
Digital feedthrough is a measure of the impulse injected into the analog output of the DAC from the digital inputs of the DAC, but is measured when the DAC output is not updated. It is specified in nV-s and measured with a full-scale code change on the data bus, that is, from all 0s to all 1s, and vice versa.
Rev. C | Page 12 of 20
Page 13
AD5063

THEORY OF OPERATION

The AD5063 is a single 16-bit, serial input, voltage-output DAC. It operates from supply voltages of 2.7 V to 5.5 V. Data is written to the AD5063 in a 24-bit word format via a 3-wire serial interface.
The AD5063 incorporates a power-on reset circuit that ensures the DAC output powers up to midscale. The device also has a software power-down mode pin that reduces the typical current consumption to less than 1 μA.

DAC ARCHITECTURE

The DAC architecture of the AD5063 consists of two matched DAC sections. A simplified circuit diagram is shown in Figure 27. The four MSBs of the 16-bit data-word are decoded to drive 15 switches, E1 to E15. Each of these switches connects one of 15 matched resistors to either the DACGND or V buffer output. The remaining 12 bits of the data-word drive Switches S0 to S11 of a 12-bit voltage mode R-2R ladder network.
2R
2R
2R
S1
S0
V
REF
12-BIT R-2R L ADDER FOUR MSBs DECODED I NTO
Figure 27. DAC Ladder Structure
2R
S11
2R
E12RE2
15 EQUAL SEGMENTS
2R
E15
REF
V
OUT
04766-027
The write sequence begins by bringing the
line low. Data
SYNC from the DIN line is clocked into the 24-bit shift register on the falling edge of SCLK. The serial clock frequency can be as high as 30 MHz, making these parts compatible with high speed DSPs. On the 24
th
falling clock edge, the last data bit is clocked in and the programmed function is executed (that is, a change in the DAC register contents and/or a change in the mode of operation).
At this stage, the
line can be kept low or be brought
SYNC
high. In either case, it must be brought high for a minimum of 12 ns before the next write sequence, so that a falling edge of
can initiate the next write sequence. Because the
SYNC
SYNC
buffer draws more current when VIH = 1.8 V than it does when V
= 0.8 V,
IH
should be idled low between write sequences
SYNC
for even lower power operation of the part. As previously indi­cated, however, it must be brought high again just before the next write sequence.

INPUT SHIFT REGISTER

The input shift register is 24 bits wide (see Figure 28). PD1 and PD0 are bits that control the operating mode of the part (normal mode or any one of the three power-down modes). There is a more complete description of the various modes in the Power-Down Modes section. The next 16 bits are the data bits. These are transferred to the DAC register on the 24 edge of SCLK.
th
falling

REFERENCE BUFFER

The AD5063 operates with an external reference. The reference input (V
) has an input range of 2 V to AVDD − 50 mV. This
REF
input voltage is used to provide a buffered reference for the DAC core.

SERIAL INTERFACE

The AD5063 has a 3-wire serial interface (
DIN) that is compatible with SPI, QSPI, and MICROWIRE interface standards, as well as most DSPs. (See for a timing diagram of a typical write sequence.)
0000 00PD1PD0
, SCLK, and
SYNC
Figure 2
DB15 (MSB) DB0 (LSB)
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
NORMAL OPERATION
0
0
THREE-STATE
0
1
100kTO GND
1
0
1kTO GND
1
1
Figure 28. Input Register Contents
SYNC INTERRUPT
In a normal write sequence, the
least 24 falling edges of SCLK, and the DAC is updated on the
th
24
falling edge. However, if
th
24
falling edge, it acts as an interrupt to the write sequence.
SYNC
The shift register is reset and the write sequence is seen as invalid. Neither an update of the DAC register contents nor a change in the operating mode occurs (see ). Figure 31
DATA BITS
POWER-DOWN MODES
line is kept low for at
SYNC
is brought high before the
04766-028
Rev. C | Page 13 of 20
Page 14
AD5063

POWER-ON TO MIDSCALE

The AD5063 contains a power-on reset circuit that controls the output voltage during power-up. The DAC register is filled with the midscale code, and the output voltage is midscale until a valid write sequence is made to the DAC. This is useful in applications where it is important to know the state of the DAC output while it is in the process of powering up.

SOFTWARE RESET

The device can be put into software reset by setting all bits in the DAC register to 1; this includes writing 1s to Bits D23 to D16, which is not the normal mode of operation. Note that the
interrupt command cannot be performed if a software
SYNC reset command is started.

POWER-DOWN MODES

The AD5063 contains four separate modes of operation. These modes are software-programmable by setting two bits (DB17 and DB16) in the control register. Tab le 6 shows how the state of the bits corresponds to the operating mode of the device.
Table 6. Modes of Operation for the AD5063
DB17 DB16 Operating Mode 0 0 Normal operation Power-down mode: 0 1 Three-state 1 0 100 kΩ to GND 1 1 1 kΩ to GND
When both bits are set to 0, the part has normal power con­sumption. However, for the three power-down modes, the supply current falls to 200 nA at 5 V (50 nA at 3 V). Not only does the supply current fall, but the output stage is also internally switched from the output of the amplifier to a resistor network of known values. This has the advantage that the output impedance of the part is known while the part is in power-down mode. There are three options: The output can be connected internally to GND through either a 1 kΩ resistor or a 100 kΩ resistor, or it can be left open-circuited (three-stated). The output stage is illustrated in Figure 29.
AD5063
DAC
POWER-DOW N
CIRCUITRY
Figure 29. Output Stage During Power-Down
RESISTOR NETWORK
V
OUT
04766-029
The bias generator, DAC core, and other associated linear circuitry are all shut down when the power-down mode is activated. However, the contents of the DAC register are unaffected when in power-down. The time to exit power-down is typically
2.5 μs for V
= 5 V, and 5 μs for VDD = 3 V (see Figure 19).
DD

MICROPROCESSOR INTERFACING

AD5063 to ADSP-2101/ADSP-2103 Interface

Figure 30 shows a serial interface between the AD5063 and the ADSP-2101/ADSP-2103. The ADSP-2101/ADSP-2103 should be set up to operate in the SPORT transmit alternate framing mode. The ADSP-2101/ADSP-2103 SPORT are programmed through the SPORT control register and should be configured as follows: internal clock operation, active low framing, and 16-bit word length. Transmission is initiated by writing a word to the Tx register after the SPORT has been enabled.
ADSP-2101/
ADSP-2103
1
ADDITIONAL PI NS OMIT TED FOR CL ARITY
1
TFS
DT
SCLK
Figure 30. AD5063 to ADSP-2101/ADSP-2103 Interface
AD5063
SYNC
DIN
SCLK
04766-030
SCLK
SYNC
DIN
DB23 DB23 DB0DB0
INVALID WRITE SEQUENCE:
SYNC HIGH BEFO RE 24
TH
FALLING EDGE
Figure 31.
SYNC
Rev. C | Page 14 of 20
OUTPUT UPDATES O N THE 24THFALLING EDGE
Interrupt Facility
VALID WRITE SEQUENCE:
04766-031
Page 15
AD5063

AD5063 to 68HC11/68L11 Interface

Figure 32 shows a serial interface between the AD5063 and the 68HC11/68L11 microcontroller. SCK of the 68HC11/68L11 drives the SCLK pin of the AD5063, and the MOSI output drives the serial data line of the DAC. The
SYNC
signal is
derived from a port line (PC7). The setup conditions for correct operation of this interface require that the 68HC11/68L11 be configured so that its CPOL bit is 0 and its CPHA bit is 1. When data is being transmitted to the DAC, the
SYNC
line is taken
low (PC7). When the 68HC11/68L11 are configured with their CPOL bit set to 0 and their CPHA bit set to 1, data appearing on the MOSI output is valid on the falling edge of SCK. Serial data from the 68HC11/68L11 is transmitted in 8-bit bytes with only eight falling clock edges occurring in the transmit cycle. Data is transmitted MSB first. To load data to the AD5063, PC7 is left low after the first eight bits are transferred, and then a second serial write operation is performed to the DAC, with PC7 taken high at the end of this procedure.
68HC11/
1
68L11
PC7
SCK
MOSI
1
ADDITIONAL PI NS OMIT TED FOR CL ARITY
Figure 32. AD5063 to 68HC11/68L11 Interface
SYNC
SCLK
DIN
AD5063
1

AD5063 to Blackfin® ADSP-BF53x Interface

Figure 33 shows a serial interface between the AD5063 and the Blackfin® ADSP-BF53x microprocessor. The ADSP-BF53x processor family incorporates two dual-channel synchronous serial ports, SPORT1 and SPORT0, for serial and multiprocessor communications. Using SPORT0 to connect to the AD5063, the setup for the interface is as follows: DT0PRI drives the DIN pin of the AD5063, TSCLK0 drives the SCLK of the part, and TFS0 drives
1
ADDITIONAL PI NS OMIT TED FOR CL ARITY
.
SYNC
ADSP-BF53x
1
DT0PRI
TSCLK0
TFS0
Figure 33. AD5063 to Blackfin ADSP-BF53x Interface
DIN
SCLK
SYNC
AD5063
1
04766-032
04766-033

AD5063 to 80C51/80L51 Interface

Figure 34 shows a serial interface between the AD5063 and the 80C51/80L51 microcontroller. The setup for the interface is as follows: TxD of the 80C51/80L51 drives SCLK of the AD5063, and RxD drives the serial data line of the part. The
SYNC
signal
is again derived from a bit-programmable pin on the port. In this case, Port Line P3.3 is used. When data is to be transmitted to the AD5063, P3.3 is taken low. The 80C51/80L51 transmits data only in 8-bit bytes; therefore, only eight falling clock edges occur in the transmit cycle. To load data to the DAC, P3.3 is left low after the first eight bits are transmitted, and a second write cycle is initiated to transmit the second byte of data. P3.3 is taken high following the completion of this cycle. The 80C51/80L51 output the serial data in a format that has the LSB first. The AD5063 requires its data with the MSB as the first bit received. The 80C51/80L51 transmit routine should take this into account.
80C51/80L51
1
ADDITIONAL PI NS OMIT TED FOR CL ARITY
1
P3.3
TxD
RxD
Figure 34. AD5063 to 80C51/80L51 Interface
SYNC
SCLK
DIN
AD5063
1

AD5063 to MICROWIRE Interface

Figure 35 shows an interface between the AD5063 and any MICROWIRE-compatible device. Serial data is shifted out on the falling edge of the serial clock and clocked into the AD5063 on the rising edge of the SK.
MICROWIRE
1
ADDITIONAL PI NS OMIT TED FOR CL ARITY
1
CS
SK
SO
Figure 35. AD5063 to MICROWIRE Interface
SYNC
SCLK
DIN
AD5063
1
04766-034
04766-035
Rev. C | Page 15 of 20
Page 16
AD5063

APPLICATIONS

CHOOSING A REFERENCE FOR THE AD5063

To achieve optimum performance of the AD5063, thought should be given to the choice of a precision voltage reference. The AD5063 has one reference input, V reference input is used to supply the positive input to the DAC; therefore, any error in the reference is reflected in the DAC.
There are four possible sources of error when choosing a voltage reference for high accuracy applications: initial accuracy, ppm drift, long-term drift, and output voltage noise. Initial accuracy on the output voltage of the DAC leads to a full-scale error in the DAC. To minimize these errors, a reference with high initial accuracy is preferred. Also, choosing a reference with an output trim adjustment, such as the ADR423, allows a system designer to trim out system errors by setting a reference voltage to a voltage other than the nominal. The trim adjustment can also be used at any point within the operating temperature range to trim out error.
Because the supply current required by the AD5063 is extremely low, the parts are ideal for low supply applications. The ADR395 voltage reference is recommended; it requires less than 100 μA of quiescent current and can, therefore, drive multiple DACs in one system, if required. It also provides very good noise performance at 8 μV p-p in the 0.1 Hz to 10 Hz range.
7V
ADR395
5V
. The voltage on the
REF
Table 7. Recommended Precision References for the AD5063
Initial
Part No.
Accuracy (mV max)
Temperature Drift (ppm/°C max)
0.1 Hz to 10 Hz Noise (μV p-p typ)
ADR435 ±2 3 (R-8) 8 ADR425 ±2 3 (R-8) 3.4 ADR02 ±3 3 (R-8) ADR02 ±3 3 (SC-70)
10 10
ADR395 ±5 9 (TSOT-23) 8

BIPOLAR OPERATION USING THE AD5063

The AD5063 has been designed for single-supply operation, but a bipolar output range is also possible by using the circuit shown in Figure 37. This circuit yields an output voltage range of ±4.096 V. Rail-to-rail operation at the amplifier output is achievable using AD8675/AD8031/AD8032 or an OP196.
The output voltage for any input code can be calculated as
O
×=
VV
⎞ ⎟
536,65
R2R1D
+
×
⎜ ⎝
R1
V
DDDD
where D represents the input code in decimal (0 to 65,536).
With V
= 5 V, R1 = R2 = 30 kΩ
REF
10
×=D
V
O
65536
⎟ ⎠
V5
R2
×
R1
3-WIRE
SERIAL
INTERFACE
SYNC
SCLK
DIN
Figure 36. ADR395 as a Reference to AD5063
AD5063
V
OUT
= 0V TO 5V
Long-term drift is a measure of how much the reference drifts over time. A reference with a tight long-term drift specification ensures that the overall solution remains relatively stable during its entire lifetime. The temperature coefficient of a reference’s output voltage affects INL, DNL, and TUE. A reference with a tight temperature coefficient specification should be chosen to reduce the temperature dependence of the DAC output voltage on ambient conditions.
In high accuracy applications, which have a relatively low tolerance for noise, reference output voltage noise needs to be considered. It is important to choose a reference with as low an output noise voltage as practical for the system noise resolution required. Precision voltage references, such as the ADR435, produce low output noise in the 0.1 Hz to 10 Hz region. Exam­ples of some recommended precision references for use as the supply to the AD5063 are shown in Tabl e 7.
This is an output voltage range of ±5 V, with 0x0000 corresponding to a −5 V output and 0xFFFF corresponding to a +5 V output.
V
+4.096
04766-036
SERIAL
INTERFACE
+5V
0.1
µ
F
VV
DD
SYNC
DIN
SCLK
DACGND
µ
F
10
+
0.1µF
R
FB
REF
AD5063
AGND
Figure 37. Bipolar Operation
R
FB
INV
R
INV
OUT
+5V
–5V
EXTERNAL
OP A
MP
BIPOLAR
OUTPUT
04766-037
Rev. C | Page 16 of 20
Page 17
AD5063

USING THE AD5063 WITH A GALVANICALLY ISOLATED INTERFACE CHIP

In process-control applications in industrial environments, it is often necessary to use a galvanically isolated interface to protect and isolate the controlling circuitry from hazardous common­mode voltages that may occur in the area where the DAC is functioning. iCoupler® provides isolation in excess of 2.5 kV. Because the AD5063 uses a 3-wire serial logic interface, the ADuM130x family provides an ideal digital solution for the DAC interface.
The ADuM130x isolators provide three independent isolation channels in a variety of channel configurations and data rates. They operate across the full range of 2.7 V to 5.5 V, providing compatibility with lower voltage systems as well as enabling a voltage translation functionality across the isolation barrier.
Figure 38 shows a typical galvanically isolated configuration using the AD5063. The power supply to the part also needs to be isolated; this is accomplished by using a transformer. On the DAC side of the transformer, a 5 V regulator provides the 5 V supply required for the AD5063.
5V
POWER 10µF 0.1µF
SCLK
SDI
V1A
V1B
REGULATOR
V
DD
SCLKV0A
AD5063ADMu1300
V
OUTV0B SYNC

POWER SUPPLY BYPASSING AND GROUNDING

When accuracy is important in a circuit, it is helpful to consider carefully the power supply and ground return layout on the board. The printed circuit board containing the AD5063 should have separate analog and digital sections, each on its own area of the board. If the AD5063 is in a system where other devices require an AGND-to-DGND connection, the connection should be made at one point only. This ground point should be as close as possible to the AD5063.
The power supply to the AD5063 should be bypassed with 10 μF and 0.1 μF capacitors. The capacitors should physically be as close as possible to the device, with the 0.1 μF capacitor ideally right up against the device. The 10 μF capacitors are the tantalum bead type. It is important that the 0.1 μF capacitor has low effective series resistance (ESR) and low effective series inductance (ESI), as do common ceramic types of capacitors. This 0.1 μF capacitor provides a low impedance path to ground for high frequencies caused by transient currents from internal logic switching.
The power supply line itself should have as large a trace as possible to provide a low impedance path and to reduce glitch effects on the supply line. Clocks and other fast switching digital signals should be shielded from other parts of the board by a digital ground. Avoid crossover of digital and analog signals, if possible. When traces cross on opposite sides of the board, ensure that they run at right angles to each other to reduce feedthrough effects on the board. The best board layout technique is the microstrip technique where the component side of the board is dedicated to the ground plane only, and the signal traces are placed on the solder side. However, this is not always possible with a 2-layer board.
A DIN
DAT
V1C
Figure 38. AD5063 with a Galvanically Isolated Interface
V0C
GND
04766-039
Rev. C | Page 17 of 20
Page 18
AD5063

OUTLINE DIMENSIONS

3.10
3.00
2.90
6
10
3.10
3.00
2.90
1
PIN 1
0.50 BSC
0.95
0.85
0.75
0.15
0.05
0.33
0.17
COPLANARITY
0.10
COMPLIANT TO JEDEC STANDARDS MO-187-BA
Figure 39. 10-Lead Mini Small Outline Package [MSOP]

ORDERING GUIDE

Model Temperature Range INL Settling Time Package Description Package Option Branding
AD5063BRMZ1 −40°C to +85°C 1 LSB 4 μs typ 10-Lead MSOP RM-10 D49 AD5063BRMZ-REEL71 −40°C to +85°C 1 LSB 4 μs typ 10-Lead MSOP RM-10 D49 AD5063BRMZ-1 AD5063BRMZ-1-REEL7 EVAL-AD5063EB
1
Z = RoHS Compliant Part.
1
−40°C to +85°C 1 LSB 1 μs max 10-Lead MSOP RM-10 DCG
1
−40°C to +85°C 1 LSB 1 μs max 10-Lead MSOP RM-10 DCG Evaluation Board
5.15
4.90
4.65
5
1.10 MAX
SEATING PLANE
0.23
0.08
8° 0°
(RM-10)
Dimensions shown in millimeters
0.80
0.60
0.40
Rev. C | Page 18 of 20
Page 19
AD5063
NOTES
Rev. C | Page 19 of 20
Page 20
AD5063
NOTES
©2005–2009 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D04766-0-8/09(C)
Rev. C | Page 20 of 20
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