2.7 V to 5.5 V, 250 μA, Rail-to-Rail Output,
Dual 16-Bit nanoDAC
Data Sheet AD5663
Rev. A Document Feedback
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FEATURES
Low power, dual 16-bit nanoDAC
Relative accuracy: ±12 LSBs maximum
Guaranteed monotonic by design
10-lead MSOP and 3 mm × 3 mm LFCSP_WD
2.7 V to 5.5 V power supply
Per channel power-down
Power-on reset to zero scale or midscale
Hardware LDAC and CLR functions
Serial interface; up to 50 MHz
APPLICATIONS
Process control
Data acquisition systems
Portable battery-powered instruments
Digital gain and offset adjustment
Programmable voltage and current sources
Programmable attenuators
FUNCTIONAL BLOCK DIAGRAM
INTERFACE
LOGIC
SCLK
SYNC
DIN
CLR
INPUT
REGISTER
INPUT
REGISTER
DAC
REGISTER
DAC
REGISTER
V
DD
GND
POWER-ON
RESET
STRING
DAC A
STRING
DAC B
BUFFER
BUFFER
V
REF
POWER-DOWN
LOGIC
V
OUT
A
V
OUT
B
AD5663
LDAC
LDAC
05855-001
Figure 1.
Table 1. Related Devices
Part No. Description
AD5623R/AD5643R/AD5663R 2.7 V to 5.5 V, dual 12-/14-/16-bit
DACs with internal reference
GENERAL DESCRIPTION
The AD5663, a member of the nanoDAC® family, is a low
power, dual, 16-bit buffered voltage-out DAC that operates from a
single 2.7 V to 5.5 V supply and is guaranteed monotonic by
design.
The AD5663 requires an external reference voltage to set the
output range of the DAC. The part incorporates a power-on
reset circuit that ensures the DAC output powers up to 0 V or
midscale (AD5663BRMZ-1) and remains there until a valid
write takes place. The part contains a power-down feature that
reduces the current consumption of the device to 480 nA at 5 V
and provides software-selectable output loads while in power-
down mode.
The low power consumption of this part in normal operation
makes it ideally suited to portable, battery-operated equipment.
The power consumption is 1.25 mW at 5 V, going down to
2.4 μW in power-down mode.
The on-chip precision output amplifier of the AD5663 allows
rail-to-rail output swing to be achieved.
The AD5663 uses a versatile, 3-wire serial interface that
operates at clock rates up to 50 MHz and is compatible with
standard SPI®, QSPI™, MICROWIRE™, and DSP interface
standards.
PRODUCT HIGHLIGHTS
1. Dual 16-bit DAC; relative accuracy of ±12 LSBs maximum.
2. Available in 10-lead MSOP and 10-lead, 3 mm × 3 mm
LFCSP_WD packages.
3. Low power; typically consumes 0.6 mW at 3 V and
1.25 mW at 5 V.
4. 7 μs maximum settling time.
AD5663 Data Sheet
Rev. A | Page 2 of 24
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
Functional Block Diagram .............................................................. 1
General Description ......................................................................... 1
Product Highlights ....................................................................... 1
Revision History ............................................................................... 2
Specifications ..................................................................................... 3
AC Characteristics ........................................................................ 4
Timing Characteristics ................................................................ 5
Timing Diagram ........................................................................... 5
Absolute Maximum Ratings ............................................................ 6
ESD Caution .................................................................................. 6
Pin Configuration and Function Description .............................. 7
Typical Performance Characteristics ............................................. 8
Terminology .................................................................................... 12
Theory of Operation ...................................................................... 14
D/A Section ................................................................................. 14
Resistor String ............................................................................. 14
Output Amplifier ........................................................................ 14
Serial Interface ............................................................................ 14
Input Shift Register .................................................................... 14
SYNC Interrupt .......................................................................... 15
Power-On Reset .......................................................................... 15
Software Reset ............................................................................. 15
Power-Down Modes .................................................................. 16
LDAC Function .......................................................................... 16
Microprocessor Interfacing ....................................................... 18
Applications ..................................................................................... 19
Choosing a Reference for the AD5663 .................................... 19
Using a Reference as a Power Supply for the AD5663 .......... 19
Bipolar Operation Using the AD5663 ..................................... 20
Using the AD5663 with a Galvanically Isolated Interface .... 20
Power Supply Bypassing and Grounding ................................ 20
Outline Dimensions ....................................................................... 21
Ordering Guide .......................................................................... 21
REVISION HISTORY
11/2016—Rev. 0 to Rev. A
Changed ADSP-BF53x to ADSP-BF537 ..................... Throughout
Added Figure 4; Renumbered Sequentially .................................. 7
Changes to Table 6 ............................................................................ 7
Change to Figure 28 ....................................................................... 14
Changes to Software Reset Section .............................................. 15
Changes to Figure 33 ...................................................................... 18
Updated Outline Dimensions ....................................................... 21
Changes to Ordering Guide .......................................................... 21
4/2006—Revision 0: Initial Version
Data Sheet AD5663
Rev. A | Page 3 of 24
SPECIFICATIONS
VDD = 2.7 V to 5.5 V; RL = 2 kΩ to GND; CL = 200 pF to GND; VREF = VDD; all specifications TMIN to TMAX, unless otherwise noted.
Table 2.
A Grade1 B Grade1
Parameter Min Typ Max Min Typ Max Unit Conditions/Comments
STATIC PERFORMANCE2
AD5663
Resolution 16 16 Bits
Relative Accuracy ±8 ±16 ±6 ±12 LSB
Differential Nonlinearity ±1 ±1 LSB Guaranteed monotonic by design
Zero-Scale Error +2 +10 +2 +10 mV All 0s loaded to DAC register
Offset Error ±1 ±10 ±1 ±10 mV
Full-Scale Error −0.15 ±1 −0.15 ±1 % of FSR All 1s loaded to DAC register
Gain Error ±1.5 ±1.5 % of FSR
Zero-Scale Error Drift3 ±2 ±2 µV/°C
Gain Temperature Coefficient ±2.5 ±2.5 ppm Of FSR/°C
DC Power Supply Rejection Ratio −100 −100 dB DAC code = midscale, VDD ± 10%
DC Crosstalk 10 10 µV Due to full-scale output change
RL = 2 kΩ to GND or VDD
10 10 µV/mA Due to load current change
5 5 µV Due to powering down (per channel)
OUTPUT CHARACTERISTICS2
Output Voltage Range 0 VDD 0 VDD V
Capacitive Load Stability 2 2 nF RL = ∞
10 10 nF RL = 2 kΩ
DC Output Impedance 0.5 0.5 Ω
Short-Circuit Current 30 30 mA VDD = 5 V
Power-Up Time 4 4 s Coming out of power-down mode;
VDD = 5 V
REFERENCE INPUTS
Reference Current 170 200 170 200 µA VREF = VDD = 5.5 V, 3.6 V
Reference Input Range 0.75 VDD 0.75 VDD V
Reference Input Impedance 26 26 kΩ
LOGIC INPUTS3
Input Current ±2 ±2 µA All digital inputs
VINL, Input Low Voltage 0.8 0.8 V VDD = 5 V, 3 V
VINH, Input High Voltage 2 2 V VDD = 5 V, 3 V
Pin Capacitance 3 3 pF DIN, SCLK, and SYNC
19 19 pF
LDAC and CLR
POWER REQUIREMENTS
VDD 2.7 5.5 2.7 5.5 V
IDD (Normal Mode)4 V
IH = VDD and VIL = GND
VDD = 4.5 V to 5.5 V 250 450 250 450 µA
VDD = 2.7 V to 3.6 V 200 425 200 425 µA
IDD (All Power-Down Modes)5 V
IH = VDD, VIL = GND
VDD = 4.5 V to 5.5 V 0.48 1 0.48 1 µA
VDD = 2.7 V to 3.6 V 0.2 1 0.2 1 µA
1 Temperature range: A grade and B grade are both equal to −40°C to +105°C.
2 Linearty calculated using a reduced code range: AD5663 (Code 512 to Code 65024). Output unloaded.
3 Guaranteed by design and characterization, not production tested.
4 Interface inactive. All DACs active. DAC outputs unloaded.
5 Both DACs powered down.
AD5663 Data Sheet
Rev. A | Page 4 of 24
AC CHARACTERISTICS
VDD = 2.7 V to 5.5 V; RL = 2 kΩ to GND; CL = 200 pF to GND; VREF = VDD; all specifications TMIN to TMAX, unless otherwise noted.1
Table 3.
Parameter2 Min Typ Max Unit Conditions/Comments
Output Voltage Settling Time 4 7 μs 1/4 to 3/4 scale settling to ±2 LSB
Slew Rate 1.8 V/μs
Digital-to-Analog Glitch Impulse 10 nV-s 1 LSB change around major carry
Digital Feedthrough 0.1 nV-s
Reference Feedthrough −90 dBs VREF = 2 V ± 0.1 V p-p, frequency 10 Hz to 20 MHz
Digital Crosstalk 0.1 nV-s
Analog Crosstalk 1 nV-s
DAC-to-DAC Crosstalk 1 nV-s
Multiplying Bandwidth 340 kHz VREF = 2 V ± 0.1 V p-p
Total Harmonic Distortion −80 dB VREF = 2 V ± 0.1 V p-p; frequency = 10 kHz
Output Noise Spectral Density 120 nV/√Hz DAC code = midscale, 1 kHz
100 nV/√Hz DAC code = midscale, 10 kHz
Output Noise 15 μV p-p 0.1 Hz to 10 Hz
1 Guaranteed by design and characterization, not production tested.
2 See the Terminology section.
Data Sheet AD5663
Rev. A | Page 5 of 24
TIMING CHARACTERISTICS
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.
VDD = 2.7 V to 5.5 V; all specifications TMIN to TMAX, unless otherwise noted.1
Table 4.
Limit at TMIN, TMAX
Parameter VDD = 2.7 V to 5.5 V Unit Conditions/Comments
t12 20 ns min SCLK cycle time
t2 9 ns min SCLK high time
t3 9 ns min SCLK low time
t4 13 ns min SYNC to SCLK falling edge setup time
t5 5 ns min Data setup time
t6 5 ns min Data hold time
t7 0 ns min SCLK falling edge to SYNC rising edge
t8 15 ns min Minimum SYNC high time
t9 13 ns min SYNC rising edge to SCLK fall ignore
t10 0 ns min SCLK falling edge to SYNC fall ignore
t11 10 ns min LDAC pulse width low
t12 15 ns min SCLK falling edge to LDAC rising edge
t13 5 ns min CLR pulse width low
t14 0 ns min SCLK falling edge to LDAC falling edge
t15 300 ns max CLR pulse activation time
1 Guaranteed by design and characterization; not production tested.
2 Maximum SCLK frequency is 50 MHz at VDD = 2.7 V to 5.5 V.
TIMING DIAGRAM
05855-002
t
4
t
3
SCLK
SYNC
DIN
t
1
t
2
t
5
t
6
t
7
t
8
DB23
t
9
t
10
t
11
t
12
LDAC
1
LDAC
2
t
14
1
ASYNCHRO NOUS LDAC UPDAT E M ODE.
2
SYNCHRO NOUS LDAC UPDAT E M ODE.
CLR
t
13
t
15
V
OUT
DB0
Figure 2. Serial Write Operation
AD5663 Data Sheet
Rev. A | Page 6 of 24
ABSOLUTE MAXIMUM RATINGS
TA = 25°C, unless otherwise noted.
Table 5.
Parameter Rating
VDD to GND −0.3 V to +7 V
VOUT to GND −0.3 V to VDD + 0.3 V
VREF to GND −0.3 V to VDD + 0.3 V
Digital Input Voltage to GND −0.3 V to VDD + 0.3 V
Operating Temperature Range
Industrial −40°C to +105°C
Storage Temperature Range −65°C to +150°C
Junction Temperature (TJ max) 150°C
Power Dissipation (TJ max − TA)/θJA
LFCSP_WD Package (4-Layer Board)
θJA Thermal Impedance 61°C/W
MSOP Package (4-Layer Board)
θ
JA
Thermal Impedance
142°C/W
θJC Thermal Impedance 43.7°C/W
Reflow Soldering Peak Temperature
Pb-Free 260(+0/−5)°C
Stresses at or above those listed under Absolute Maximum
Ratings may cause permanent damage to the product. This is a
stress rating only; functional operation of the product at these
or any other conditions above those indicated in the operational
section of this specification is not implied. Operation beyond
the maximum operating conditions for extended periods may
affect product reliability.
ESD CAUTION
Data Sheet AD5663
Rev. A | Page 7 of 24
PIN CONFIGURATION AND FUNCTION DESCRIPTION
1
V
OUT
A
10
V
REF
2
V
OUT
B
9
V
DD
3
GND
8
DIN
4
LDAC
7
SCLK
5
CLR
6
SYNC
AD5663
TOP VIEW
(No t t o Scal e)
05855-003
Figure 3. 10-Lead MSOP Pin Configuration
1VOUTA
2
VOUTB
3GND
4LDAC
5
CLR
10 VREF
9 VDD
8DIN
7SCLK
6 SYNC
05855-100
AD5663
TOP VIEW
(Not to Scal e)
NOTES
1. EXPOSED PAD. THE EXPOSED PAD IS INTE RNALLY FLOATING
AND IS RE COMM E NDE D TO BE CO NNE CTED TO GROUND.
Figure 4. 10-Lead LFCSP Pin Configuration
Table 6. Pin Function Descriptions
Pin No.
10-Lead
MSOP
10-Lead
LFCSP Mnemonic Description
1 1 VOUTA Analog Output Voltage from DAC A. The output amplifier has rail-to-rail operation.
2 2 VOUTB Analog Output Voltage from DAC B. The output amplifier has rail-to-rail operation.
3 3 GND Ground Reference Point for All Circuitry on the Device.
4 4 LDAC Pulsing this pin low allows any or all DAC registers to be updated if the input registers have new data. This
allows simultaneous update of all DAC outputs. Alternatively, this pin can be tied permanently low.
5 5 CLR Asynchronous Clear Input. The CLR input is falling edge sensitive. While CLR is low, all LDAC pulses are
ignored. When CLR is activated, zero scale is loaded to all input and DAC registers. This clears the
output to 0 V. The device exits clear code mode on the 24th falling edge of the next write to the
device. If CLR is activated during a write sequence, the write is aborted.
6 6 SYNC Active Low Control Input. This is the frame synchronization signal for the input data. When SYNC goes
low, it powers on the SCLK and DIN buffers and enables the input shift register. Data is transferred in
on the falling edges of the next 24 clocks. If SYNC is taken high before the 24th falling edge, the rising
edge of SYNC acts as an interrupt, and the write sequence is ignored by the device.
7 7 SCLK Serial Clock Input. Data is clocked into the input shift register on the falling edge of the serial clock
input. Data can be transferred at rates up to 50 MHz.
8
8
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.
9 9 VDD Power Supply Input. These devices can be operated from 2.7 V to 5.5 V, and the supply must be
decoupled with a 10 µF capacitor in parallel with a 0.1 µF capacitor to GND.
10 10 VREF Reference Voltage Input.
N/A1 EPAD Exposed Pad. The exposed pad is internally floating and is recommended to be connected to ground.
1 N/A means not applicable.
AD5663 Data Sheet
Rev. A | Page 8 of 24
TYPICAL PERFORMANCE CHARACTERISTICS
CODE
INL ERROR (LSB)
10
4
6
8
0
2
–6
–10
–8
–2
–4
0 5k 10k 15k 20k 25k 30k 35k 40k 45k 50k 55k 60k 65k
05855-004
V
DD
= V
REF
= 5V
T
A
= 25°C
Figure 5. INL
CODE
DNL ERROR (LSB)
1.0
0.6
0.4
0.2
0.8
0
–0.4
–0.2
–0.6
–1.0
–0.8
0 10k 20k 30k 40k 50k 60k
05855-005
V
DD
= V
REF
= 5V
T
A
= 25°C
Figure 6. DNL
TEMPERATURE (°C)
ERROR (LSB)
8
6
4
2
–6
–4
–2
0
–8
–40 –20 40200 1008060 120
05855-006
MIN DNL
MAX DNL
MAX INL
MIN INL
V
DD
= V
REF
= 5V
Figure 7. INL Error and DNL Error vs. Temperature
V
REF
(V)
ERROR (LSB)
10
4
6
8
2
0
–8
–6
–4
–2
–10
0.75 1.25 1.75 2.25 4.253.753.252.75 4.75
05855-007
MIN DNL
MAX DNL
MAX INL
MIN INL
V
DD
= 5V
T
A
= 25°C
Figure 8. INL and DNL Error vs. VREF
V
DD
(V)
ERROR (LSB)
8
6
4
2
–6
–4
–2
0
–8
2.7 3.2 3.7 4.74.2 5.2
05855-008
MIN DNL
MAX DNL
MAX INL
MIN INL
T
A
= 25°C
Figure 9. INL and DNL Error vs. Supply
TEMPERATURE (°C)
ERROR (% FSR)
0
–0.04
–0.02
–0.06
–0.08
–0.10
–0.18
–0.16
–0.14
–0.12
–0.20
–40 –20 402001008060
05855-009
VDD = 5V
GAIN ERROR
FULL-SCALE ERROR
Figure 10. Gain Error and Full-Scale Error vs. Temperature
Data Sheet AD5663
Rev. A | Page 9 of 24
TEMPERATURE (°C)
ERROR (mV)
1.5
1.0
0.5
0
–2.0
–1.5
–1.0
–0.5
–2.5
–40 –20 402008060 100
05855-010
OFFSET ERROR
ZERO-SCALE ERROR
Figure 11. Zero-Scale and Offset Error vs. Temperature
V
DD
(V)
ERROR (% FSR)
1.0
–1.5
–1.0
–0.5
0
0.5
–2.0
2.7 3.2 3.7 4.74.2 5.2
05855-011
GAIN ERROR
FULL-SCALE ERROR
Figure 12. Gain Error and Full-Scale Error vs. Supply
VDD (V)
ERROR (mV)
1.0
0.5
0
–2.0
–1.5
–1.0
–0.5
–2.5
2.7 3.2 4.23.7 5.24.7
05855-012
ZERO-SCALE ERROR
OFFSET ERROR
TA = 25°C
Figure 13. Zero-Scale and Offset Error vs. Supply
I
DD
(mA)
NUMBER OF UNITS
8
6
4
2
0
0.230 0.235 0.240 0.245 0.250 0.255
V
DD
= 5.5V
T
A
= 25°C
05858-090
Figure 14. IDD Histogram with VDD = 5.5 V
I (mA)
ERROR VOLTAGE (V)
0.20
–0.25
–0.20
–0.15
–0.10
–0.05
0
0.05
0.10
0.15
–5 –4 –3 –2 –1 0 1 2 435
05855-014
V
DD
= V
REF
= 5V, 3V
T
A
= 25°C
DAC LOADED WITH
ZERO SCALE –
SINKING CURRENT
DAC LOADED WITH
FULL SCALE –
SOURCING CURRENT
Figure 15. Headroom at Rails vs. Source and Sink Current
TEMPERATURE (°C)
I
DD
(mA)
0.30
0.05
0.10
0.15
0.20
0.25
0
–40–200 20406080100
05855-044
T
A
= 25°C
V
DD
= V
REFIN
= 5V
V
DD
= V
REFIN
= 3V
Figure 16. Supply Current vs. Temperature
AD5663 Data Sheet
Rev. A | Page 10 of 24
05855-019
TIME BASE = 4µs/DIV
VDD = VREF = 5V
TA = 25°C
FULL-SCALE CODE CHANGE
0x0000 TO 0xFFFF
OUTPUT LOADED WITH 2kΩ
AND 200pF TO GND
VOUT = 909mV/DIV
1
Figure 17. Full-Scale Settling Time, 5 V
05855-020
CH1 2.0V CH2 500mV M100µs 125MS/s
A CH1 1.28V
8.0ns/pt
V
DD
= V
REF
= 5V
T
A
= 25°C
V
OUT
V
DD
1
2
MAX(C2)*
420.0mV
Figure 18. Power-On Reset to 0 V
05855-021
VDD = 5V
SYNC
SLCK
VOUT
1
3
CH1 5.0V
CH3 5.0V
CH2 500mV M400ns A CH1 1.4V
2
Figure 19. Exiting Power-Down to Midscale
SAMPLE NUMBER
V
OUT
(V)
2.521
2.522
2.523
2.524
2.525
2.526
2.527
2.528
2.529
2.530
2.531
2.532
2.533
2.534
2.535
2.536
2.537
2.538
0 50 100 150 350 400200 250 300 450 512
05855-058
V
DD
= V
REF
= 5V
T
A
= 25°C
5ns/SAMPLE NUMBER
GLITCH IMPULSE = 9.494nV
1LSB CHANGE AROUND
MIDSCALE (0x8000 TO 0x7FFF)
Figure 20. Digital-to-Analog Glitch Impulse (Negative)
SAMPLE NUMBER
V
OUT
(V)
2.491
2.492
2.493
2.494
2.495
2.496
2.497
2.498
0 50 100 150 350 400200 250 300 450 512
05855-059
V
DD
= V
REF
= 5V
T
A
= 25°C
5ns/SAMPLE NUMBER
ANALOG CROSSTALK = 0.424nV
Figure 21. Analog Crosstalk
FREQUENCY (Hz)
(dB)
–20
–50
–80
–30
–40
–60
–70
–90
–100
2k 4k 6k 8k 10k
05855-025
V
DD
= 5V
T
A
= 25°C
DAC LOADED WITH FULL SCALE
V
REF
= 2V ± 0.3V p-p
Figure 22. Total Harmonic Distortion
Data Sheet AD5663
Rev. A | Page 11 of 24
CAPACITANCE (nF)
TIME (µs)
16
14
12
10
8
6
4
012 34567 9810
05855-026
V
REF
= V
DD
T
A
= 25°C
V
DD =
5V
V
DD =
3V
Figure 23. Settling Time vs. Capacitive Load
05855-027
1
Y AXIS = 2µV/DIV
X AXIS = 4s/DIV
V
DD
= V
REF
= 5V
T
A
= 25°C
DAC LOADED WITH MIDSCALE
Figure 24. 0.1 Hz to 10 Hz Output Noise Plot
FREQUENCY (Hz)
OUTPUT NOISE (nV/ Hz)
800
600
700
400
500
100
200
300
0
10 100k10k1k100 1M
05855-028
V
DD
= V
REF
= 5V
T
A
= 25°C
Figure 25. Noise Spectral Density
FREQUENCY (Hz)
(dB)
5
–40
10k 100k 1M 10M
05855-029
–35
–30
–25
–20
–15
–10
–5
0
V
DD
= 5V
T
A
= 25°C
Figure 26. Multiplying Bandwidth
05855-050
VOUT A
VOUT B
3
CH3 5.0V CH4 1.0V
CH2 1.0V M200ns A CH3 1.10V
2
4
4
CLR
Figure 27. CLR Pulse Activation Time
AD5663 Data Sheet
Rev. A | Page 12 of 24
TERMINOLOGY
Relative Accuracy or Integral Nonlinearity (INL)
For the DAC, relative accuracy or integral nonlinearity is a
measurement of the maximum deviation, in LSBs, from a
straight line passing through the endpoints of the DAC transfer
function. A typical INL vs. code plot is shown in Figure 5.
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 vs. code plot is shown in Figure 6.
Zero-Scale Error
Zero-scale error is a measurement of the output error when
zero code (0x0000) is loaded to the DAC register. Ideally, the
output should be 0 V. The zero-scale error is always positive in
the AD5663 because the output of the DAC cannot go below
0 V. It is due to a combination of the offset errors in the DAC
and the output amplifier. Zero-scale error is expressed in mV.
A plot of zero-scale error vs. temperature is shown in Figure 11.
Full-Scale Error
Full-scale error is a measurement of the output error when full-
scale code (0xFFFF) is loaded to the DAC register. Ideally, the
output should be VDD − 1 LSB. Full-scale error is expressed in
percent of full-scale range. A plot of full-scale error vs. tempera-
ture is shown in Figure 10.
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 percent of the full-scale range.
Zero-Scale Error Drift
Zero-scale error drift is a measurement of the change in zero-
scale error with a change in temperature. It is expressed in µV/°C.
Gain Temperature Coefficient
Gain temperature coefficient is a measurement of the change in
gain error with changes in temperature. It is expressed in (ppm
of full-scale range)/°C.
Offset Error
Offset error is a measure of the difference between VOUT (actual)
and VOUT (ideal) expressed in mV in the linear region of the trans-
fer function. Offset error is measured on the AD5663 with
Code 512 loaded in the DAC register. It can be negative or
positive.
DC Power Supply Rejection Ratio (PSRR)
PSRR indicates how the output of the DAC is affected by changes
in the supply voltage. PSRR is the ratio of the change in VOUT to
a change in VDD for full-scale output of the DAC. It is measured
in dB. VREF is held at 2 V, and V DD is varied by ±10%.
Output Voltage Settling Time
Output voltage settling time is the amount of time it takes for
the output of a DAC to settle to a specified level for a 1/4 to 3/4
full-scale input change and is measured from the 24th falling
edge of SCLK.
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 (0x7FFF to 0x8000). See
Figure 20.
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 it 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.
Total Harmonic Distortion (THD)
Total harmonic distortion is the difference between an ideal
sine wave and its attenuated version using the DAC. The sine
wave is used as the reference for the DAC, and the THD is a
measurement of the harmonics present on the DAC output.
It is measured in dB.
Noise Spectral Density
Noise spectral density is a measurement of the internally
generated random noise. Random noise is characterized as a
spectral density (voltage per √Hz). It is measured by loading the
DAC to midscale and measuring noise at the output. It is
measured in nV/√Hz. Figure 25 shows a plot of noise spectral
density.
DC Crosstalk
DC crosstalk is the dc change in the output level of one DAC in
response to a change in the output of another DAC. It is measured
with a full-scale output change on one DAC (or soft power-down
and power-up) while monitoring another DAC kept at midscale.
It is expressed in μV.
DC crosstalk due to load current change is a measure of the
impact that a change in load current on one DAC has to another
DAC kept at midscale. It is expressed in μV/mA.
Digital Crosstalk
Digital crosstalk is the glitch impulse transferred to the output
of one DAC at midscale in response to a full-scale code change
(all 0s to all 1s and vice versa) in the input register of another
DAC. It is measured in standalone mode and is expressed
in nV-s.
Data Sheet AD5663
Rev. A | Page 13 of 24
Analog Crosstalk
Analog crosstalk is the glitch impulse transferred to the output
of one DAC due to a change in the output of another DAC. It is
measured by loading one of the input registers with a full-scale
code change (all 0s to all 1s and vice versa) while keeping
LDAC high. Then pulse LDAC low and monitor the output of
the DAC whose digital code was not changed. The area of the
glitch is expressed in nV-s.
DAC-to-DAC Crosstalk
DAC-to-DAC crosstalk is the glitch impulse transferred to the
output of one DAC due to a digital code change and subsequent
output change of another DAC. This includes both digital and
analog crosstalk. It is measured by loading one of the DACs
with a full-scale code change (all 0s to all 1s and vice versa) with
LDAC low and monitoring the output of another DAC. The
energy of the glitch is expressed in nV-s.
Multiplying Bandwidth
The amplifiers within the DAC have a finite bandwidth. The
multiplying bandwidth is a measure of this. A sine wave on the
reference (with full-scale code loaded to the DAC) appears on
the output. The multiplying bandwidth is the frequency at
which the output amplitude falls to 3 dB below the input.
AD5663 Data Sheet
Rev. A | Page 14 of 24
THEORY OF OPERATION
D/A SECTION
The AD5663 DAC is fabricated on a CMOS process. The
architecture consists of a string DAC followed by an output
buffer amplifier. Figure 28 shows a block diagram of the DAC
architecture.
DAC
REGISTER RESISTOR
STRING
REF (+)
V
DD
GND
REF (–)
V
OUT
OUTPUT
AMPLIFIER
(GAIN = +1)
05855-032
Figure 28. DAC Architecture
Because the input coding to the DAC is straight binary, the ideal
output voltage is given by
65,536
D
VV REF
OUT
where D is the decimal equivalent of the binary code that is
loaded to the DAC register. It can range from 0 to 65,535.
RESISTOR STRING
The resistor string section is shown in Figure 29. It is a string of
resistors, each of Value R. The code loaded to the DAC register
determines at which node on the string the voltage is tapped off
to be fed into the output amplifier. The voltage is tapped off by
closing one of the switches connecting the string to the amplifier.
Because it is a string of resistors, it is guaranteed monotonic.
R
R
R
R
RTO OUTPUT
AMPLIFIER
0
5855-033
Figure 29. Resistor String
OUTPUT AMPLIFIER
The output buffer amplifier can generate rail-to-rail voltages on
its output, which gives an output range of 0 V to VDD. It can drive
a load of 2 kΩ in parallel with 1000 pF to GND.
The source and sink capabilities of the output amplifier can be
seen in Figure 15. The slew rate is 1.8 V/μs with a 1/4 to 3/4
full-scale settling time of 10 μs.
SERIAL INTERFACE
The AD5663 has a 3-wire serial interface (SYNC, SCLK, and
DIN) that is compatible with SPI, QSPI, and MICROWIRE
interface standards, as well as with most DSPs. See Figure 2 for
a timing diagram of a typical write sequence.
The write sequence begins by bringing the SYNC line low. Data
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 50 MHz, making the AD5663 compatible with high speed
DSPs. On the 24th falling clock edge, the last data bit is clocked
in and the programmed function is executed; that is, there is a
change in DAC register contents and/or a change in the mode
of operation. At this stage, the SYNC line can be kept low or be
brought high. In either case, it must be brought high for a mini-
mum of 15 ns before the next write sequence so that a falling edge
of SYNC can initiate the next write sequence. Because the SYNC
buffer draws more current when VIN = 2.0 V than it does when
VIN = 0.10 V, SYNC should be idled low between write sequences
for even lower power operation. As mentioned previously,
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 30). The first
two bits are don’t cares. The next three are the Command Bit C2
to Command Bit C0 (see Table 7), followed by the 3-bit DAC
Address A2 to DAC Address A0 (see Table 8), and, finally, the
16-bit data-word. These are transferred to the DAC register on
the 24th falling edge of SCLK.
Table 7. Command Definition
C2 C1 C0 Command
0 0 0 Write to input register n
0 0 1 Update DAC register n
0 1 0 Write to input register n, update all
(software LDAC)
0 1 1 Write to and update DAC channel n
1 0 0 Power down DAC (power up)
1 0 1 Reset
1 1 0 LDAC register setup
1 1 1 Reserved
Data Sheet AD5663
Rev. A | Page 15 of 24
Table 8. Address Command
A2 A1 A0 ADDRESS (n)
0 0 0 DAC A
0 0 1 DAC B
0 1 0 Reserved
0 1 1 Reserved
1 1 1 All DACs
SYNC INTERRUPT
In a normal write sequence, the SYNC line is kept low for at
least 24 falling edges of SCLK, and the DAC is updated on the
24th falling edge. However, if SYNC is brought high before the
24th falling edge, this acts as an interrupt to the write sequence.
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).
POWER-ON RESET
The AD5663 family contains a power-on reset circuit that
controls the output voltage during power-up. The AD5663 DAC
outputs power up to 0 V, the AD5663BRMZ-1 powers up to
midscale, and the output remains there 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 output of the DAC
while it is in the process of powering up. Any events on LDAC
or CLR during power-on reset are ignored.
SOFTWARE RESET
The AD5663 contains a software reset function. Command 101 is
reserved for the software reset function (see Table 7). The software
reset command contains two reset modes that are software-
programmable by setting Bit DB0 in the control register.
Table 9 shows how the state of the bit corresponds to the mode
of operation of the device. Table 10 shows the contents of the
input shift register during the software reset mode of operation.
After a full software reset (DB0 = 1), there must be a short time
delay, approximately 5 μs, to complete the reset. During the
reset, a low pulse can be observed on the CLR line. If the next
SPI transaction commences before the CLR line returns high,
that SPI transaction is ignored.
Table 9. Software Reset Modes for the AD5663
DB0 Registers Reset to 0
0 DAC register
Input register
1 (Power-On Reset) DAC register
Input register
LDAC register
Power-down register
Table 10. 24-Bit Input Shift Register Contents for Software Reset Command
MSB LSB
DB23 to DB22 DB21 DB20 DB19 DB18 DB17 DB16 DB15 to DB1 DB0
x 1 0 1 x x x x 1/0
Don’t care Command bits (C2 to C0) Address bits (A2 to A0) Don’t care Determines software reset mode
X X C2 C1 C0 A2 A1 A0 D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
DB23 (MSB) DB0 (LSB)
COMMAND BITS ADDRESS BITS
DATA BITS
05855-034
Figure 30. Input Register Contents
DIN
DB23 DB23 DB0DB0
VALID WRITE SEQUENCE, OUTPUT UPDATES
ON THE 24
TH
FALLING EDGE
SYNC
SCLK
INVALID WRITE SEQUENCE:
SYNC HIGH BEFORE 24
TH
FALLING EDGE
05855-035
Figure 31. SYNC Interrupt Facility
AD5663 Data Sheet
Rev. A | Page 16 of 24
POWER-DOWN MODES
The AD5663 contains four separate modes of operation.
Command 100 is reserved for the power-down function
(see Table 7). These modes are software-programmable by
setting Bit DB5 and Bit DB4 in the control register. Table 11
shows how the state of the bits corresponds to the mode of
operation of the device. Any or all DACs (DAC B and DAC A)
can be powered down to the selected mode by setting the
corresponding two bits (Bit DB1 and Bit DB0) to 1. By
executing the same Command 100, any combination of DACs
can be powered up by setting Bit DB5 and Bit DB4 to normal
operation mode. Again, to select which combination of DAC
channels to power up, set the corresponding two bits (Bit DB1
and Bit DB0) to 1. See Table 12 for contents of the input shift
register during power-down/power-up operation.
The DAC output powers up to the value in the input register
while LDAC is low. If LDAC is high, the DAC output powers up
to the value held in the DAC register before power-down.
When both bits are set to 0, the part works normally with its
normal power consumption of 500 µA at 5 V. However, for the
three power-down modes, the supply current falls to 480 nA at
5 V (100 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. The outputs can either be
connected internally to GND through a 1 kΩ or 100 kΩ register
or left open-circuited (three-state) (see Figure 32).
RESISTOR
NETWORK
VOUT
RESISTOR
STRING DAC
POWER-DOWN
CIRCUITRY
AMPLIFIER
05855-036
Figure 32. Output Stage During Power-Down
The bias generator, the output amplifier, the resistor string, and
other associated linear circuitry are shut down when power-
down mode is activated. However, the contents of the DAC
register are unaffected when in power-down.
The time required to exit power-down is typically 4 µs for
VDD = 5 V and for VDD = 3 V (see Figure 19).
Table 11. Power-Down Modes of Operation for the AD5663
DB5 DB4 Operating Mode
0 0 Normal operation
Power-Down Modes
0 1 1 kΩ to GND
1 0 100 kΩ to GND
1 1 Three-state
LDAC FUNCTION
The AD5663 DAC has double-buffered interfaces consisting of
two banks of registers: input registers and DAC registers. The
input registers are connected directly to the input shift register
and the digital code is transferred to the relevant input register
on completion of a valid write sequence. The DAC registers
contain the digital code used by the resistor strings.
Access to the DAC registers is controlled by the LDAC pin.
When the LDAC pin is high, the DAC registers are latched and
the input registers can change state without affecting the
contents of the DAC registers. When LDAC is brought low,
however, the DAC registers become transparent and the
contents of the input registers are transferred to them. The
double-buffered interface is useful if the user requires
simultaneous updating of all DAC outputs. The user can write
to one of the input registers individually and then, by bringing
LDAC low when writing to the other DAC input register, all
outputs update simultaneously.
These parts each contain an extra feature whereby a DAC
register is not updated unless its input register has been updated
since the last time LDAC was brought low. Normally, when
LDAC is brought low, the DAC registers are filled with the
contents of the input registers. In the case of the AD5663, the
DAC register updates only if the input register has changed
since the last time the DAC register was updated, thereby
removing unnecessary digital crosstalk.
The outputs of all DACs can be updated simultaneously using
the hardware LDAC pin.
Table 12. 24-Bit Input Shift Register Contents of Power-Up/Power-Down Function
MSB LSB
DB23 to
DB22 DB21 DB20 DB19 DB18 DB17 DB16
DB15 to
DB6 DB5 DB4 DB3 DB2 DB1 DB0
x 1 0 0 x x x x PD1 PD0 x x DAC B DAC A
Don’t
care
Command bits (C2 to C0) Address bits (A2 to A0);
don’t care
Don’t
care
Power-down
mode
Don’t care Power down/Power up
channel selection;
set bit to 1 to select
channel
Data Sheet AD5663
Rev. A | Page 17 of 24
Synchronous LDAC: The DAC registers are updated after new
data is read in on the falling edge of the 24th SCLK pulse.
LDAC can be permanently low or pulsed, as shown in Figure 2.
Asynchronous LDAC: The outputs are not updated at the same
time that the input registers are written to. When LDAC goes
low, the DAC registers are updated with the contents of the
input register.
The LDAC register gives the user full flexibility and control over
the hardware LDAC pin. This register allows the user to select
which combination of channels to simultaneously update when
the hardware LDAC pin is executed. Setting the LDAC bit
register to 0 for a DAC channel means that the update of this
channel is controlled by the LDAC pin. If this bit is set to 1, this
channel synchronously updates; that is, the DAC register is
updated after new data is read in, regardless of the state of the
LDAC pin. It effectively sees the LDAC pin as being pulled low.
See Table 13 for the LDAC register mode of operation.
This flexibility is useful in applications where the user wants to
simultaneously update select channels while the rest of the
channels are synchronously updating
Writing to the DAC using Command 110 loads the 2-bit LDAC
register [DB1:DB0]. The default for each channel is 0; that is,
the LDAC pin works normally. Setting the bits to 1 means the
DAC register is updated regardless of the state of the LDAC pin.
See Table 14 for contents of the input shift register during the
LDAC register setup command.
Table 13. LDAC Register Mode of Operation
LDAC Bits
(DB1 to DB0) LDAC Pin LDAC Operation
0 1/0 Determined by LDAC pin
1 x = don’t care The DAC registers are updated
after new data is read in on the
falling edge of the 24th SCLK
pulse
Table 14. 24-Bit Input Shift Register Contents for LDAC Register Setup Command
MSB LSB
DB23 to DB22 DB21 DB20 DB19 DB18 DB17 DB16 DB15 to DB2 DB1 DB0
x 1 1 0 x x x x DAC B DAC A
Don’t care Command bits (C2 to C0) Address bits (A3 to A0);
Don’t care
Don’t care Set DAC to 0 or 1 for required mode of
operation
AD5663 Data Sheet
Rev. A | Page 18 of 24
MICROPROCESSOR INTERFACING
AD5663 to Blackfin ADSP-BF537 Interface
Figure 33 shows a serial interface between the AD5663 and the
Blackfin ADSP-BF537 microprocessor. The ADSP-BF537
incorporates two dual-channel synchronous serial ports, SPORT1
and SPORT0, for serial and multiprocessor communications.
When using SPORT0 to connect to the AD5663, the setup for the
interface is as follows:
DT0PRI drives the DIN pin of the AD5663.
TSCLK0 drives the SCLK of the device.
The SYNC pin is driven from TFS0.
AD5663
1
ADSP-BF5371
SYNC
TFS0
DINDT0PRI
SCLKTSCLK0
1ADDITIONAL PINS OMITTED FOR CLARITY.
05855-037
Figure 33. AD5663 to Blackfin ADSP-BF537 Interface
AD5663 to 68HC11/68L11 Interface
Figure 34 shows a serial interface between the AD5663 and the
68HC11/68L11 microcontroller. SCK of the 68HC11/68L11
drives the SCLK of the AD5663, 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 are as follows:
The 68HC11/68L11 is configured with its CPOL bit as 0.
The 68HC11/68L11 is configured with its CPHA bit as 1.
When data is being transmitted to the DAC, the SYNC line is
taken low (PC7). When the 68HC11/68L11 is configured as
previously described, data appearing on the MOSI output is
valid on the falling edge of SCK. Serial data from the
68HC11/68L11 is transmitted in 10-bit bytes with only eight
falling clock edges occurring in the transmit cycle. Data is
transmitted MSB first. To load data to the AD5663, PC7 is left
low after the first eight bits are transferred, and a second serial
write operation is performed to the DAC. PC7 is taken high at
the end of this procedure.
AD5663
1
68HC11/68L11
1
SYNC
PC7
SCLKSCK
DINMOSI
1
ADDITIONAL PINS OMITTED FOR CLARITY.
05855-038
Figure 34. AD5663 to 68HC11/68L11 Interface
AD5663 to 80C51/80L51 Interface
Figure 35 shows a serial interface between the AD5663 and the
80C51/80L51 microcontroller. The setup for the interface is as
follows:
TxD of the 80C51/80L51 drives SCLK of the AD5663.
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 AD5663, P3.3 is taken low. The 80C51/80L51
transmits data in 10-bit bytes only; thus 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 outputs the serial data in a format that has the LSB first.
The AD5663 must receive data with the MSB first. The 80C51/
80L51 transmit routine should take this into account.
AD5663
1
80C51/80L51
1
SYNC
P3.3
SCLKTxD
DINRxD
1
ADDITIONAL PINS OMITTED FOR CLARITY.
05855-039
Figure 35. AD5663 to 80C51/80L51 Interface
AD5663 to MICROWIRE Interface
Figure 36 shows an interface between the AD5663 and any
MICROWIRE-compatible device. Serial data is shifted out on
the falling edge of the serial clock and is clocked into the AD5663
on the rising edge of the SK.
AD5663
1
MICROWIRE1
SYNC
CS
SCLKSK
DINSO
1ADDITIONAL PINS OMITTED FOR CLARITY.
05855-040
Figure 36. AD5663 to MICROWIRE Interface
Data Sheet AD5663
Rev. A | Page 19 of 24
APPLICATIONS
CHOOSING A REFERENCE FOR THE AD5663
To achieve the optimum performance from the AD5663,
thought should be given to the choice of a precision voltage
reference. The AD5663 has only one reference input, VREF.
The voltage on the reference input is used to supply the positive
input to the DAC. Therefore, any error in the reference is
reflected in the DAC.
When choosing a voltage reference for high accuracy applica-
tions, the sources of error are 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 system errors out by setting a reference voltage to a voltage
other than the nominal. The trim adjustment can also be used
at temperature to trim out any error.
Long-term drift is a measurement of how much the reference
drifts over time. A reference with a tight long-term drift specifi-
cation 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 temperature dependence of the DAC output voltage in
ambient conditions.
In high accuracy applications, which have a relatively low noise
budget, 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 ADR425, produce low
output noise in the 0.1 Hz to 10 Hz range. Examples of recom-
mended precision references for use as supplies to the AD5663
are shown in the Table 15.
USING A REFERENCE AS A POWER SUPPLY FOR
THE AD5663
Because the supply current required by the AD5663 is extremely
low, an alternative option is to use a voltage reference to supply
the required voltage to the part (see Figure 37). This is especially
useful if the power supply is quite noisy, or if the system supply
voltages are at some value other than 5 V or 3 V (for example,
15 V). The voltage reference outputs a steady supply voltage for
the AD5663; see Table 15 for a suitable reference. If the low drop-
out REF195 is used, it must supply 250 μA of current to the
AD5663, with no load on the output of the DAC. When the
DAC output is loaded, the REF195 also needs to supply the
current to the load. The total current required (with a 5 kΩ
load on the DAC output) is
250 μA + (5 V/5 kΩ) = 1.25 mA
The load regulation of the REF195 is typically 2 ppm/mA,
which results in a 2.5 ppm (12.5 μV) error for the 1.25 mA
current drawn from it. This corresponds to a 0.164 LSB error.
AD5663
T
HREE-WIRE
SERIAL
INTERFACE
SYNC
SCLK
DIN
15V
5V
500µA
V
OUT
= 0V TO 5V
V
REF
V
DD
REF195
05855-041
Figure 37. REF195 as Power Supply to the AD5663
Table 15. Partial List of Precision References for Use with the AD5663
Part No. Initial Accuracy (mV Max) Temperature Drift (ppm°C Max) 0.1 Hz to 10 Hz Noise (μV p-p Typ) VOUT (V)
ADR425 ±2 3 3.4 5
ADR395 ±6 25 5 5
REF195 ±2 5 50 5
AD780 ±2 3 4 2.5/3
ADR423 ±2 3 3.4 3
AD5663 Data Sheet
Rev. A | Page 20 of 24
BIPOLAR OPERATION USING THE AD5663
The AD5663 has been designed for single-supply operation,
but a bipolar output range is also possible using the circuit in
Figure 38. The circuit gives an output voltage range of ±5 V.
Rail-to-rail operation at the amplifier output is achievable using
an AD820 or an OP295 as the output amplifier.
The output voltage for any input code can be calculated as
R1
R2
V
R1
R2R1D
VV DDDD
O536,65
where D represents the input code in decimal (0 to 65,535).
With VDD = 5 V, R1 = R2 = 10 kΩ
V5
536,65
10
D
VO
This is an output voltage range of ±5 V, with 0x0000 corre-
sponding to a −5 V output, and 0xFFFF corresponding to a
+5 V output.
THREE-WIRE
SERIAL
INTERFACE
R2 = 10kΩ
+5V
–5V
AD820/
OP295
+5V
AD5663
V
DD
V
OUT
R1 = 10kΩ
±5V
0.1µF10µF
05855-042
Figure 38. Bipolar Operation with the AD5663
USING THE AD5663 WITH
A GALVANICALLY ISOLATED INTERFACE
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 any hazardous
common-mode voltages that can occur in the area where the
DAC is functioning. iCoupler® provides isolation in excess of
2.5 kV. The AD5663 use a 3-wire serial logic interface, so the
ADuM1300 three-channel digital isolator provides the required
isolation (see Figure 39). The power supply to the part also
needs to be isolated, which is done by using a transformer. On
the DAC side of the transformer, a 5 V regulator provides the
5 V supply required for the AD5663.
0.1µF
5V
REGULATOR
GND
DIN
SYNC
SCLK
POWER 10µF
SDI
SCLK
DATA
AD5663
V
OUT
V
OB
V
OA
V
OC
V
DD
V
IC
V
IB
V
IA
ADuM1300
05855-043
Figure 39. AD5663 with a Galvanically Isolated Interface
POWER SUPPLY BYPASSING AND GROUNDING
When accuracy is important in a circuit, it is helpful to carefully
consider the power supply and ground return layout on the
board. The printed circuit board containing the AD5663 should
have separate analog and digital sections, each having its own
area of the board. If the AD5663 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 AD5663.
The power supply to the AD5663 should be bypassed with 10 μF
and 0.1 μF capacitors. The capacitors should be located as close
as possible to the device, with the 0.1 μF capacitor ideally right
up against the device. The 10 μF capacitors are of the tantalum
bead type. It is important that the 0.1 μF capacitor have low
effective series resistance (ESR) and effective series inductance
(ESI) as in, for example, common ceramic types of capacitors.
This 0.1 μF capacitor provides a low impedance path to ground
for high frequencies caused by transient currents due to 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 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 through 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.
Data Sheet AD5663
Rev. A | Page 21 of 24
OUTLINE DIMENSIONS
2.48
2.38
2.23
0.50
0.40
0.30
10
1
6
5
0.30
0.25
0.20
PIN 1 INDEX
AREA
SEATING
PLANE
0.80
0.75
0.70
1.74
1.64
1.49
0.20 REF
0.05 M AX
0.02 NO M
0.50 BSC
EXPOSED
PAD
3.10
3.00 SQ
2.90
PIN 1
INDICATOR
(R 0. 15)
FOR PRO P E R CONNECT IO N OF
THE EXPOSED PAD, REFER TO
THE PIN CO NFI G URATI ON AND
FUNCTION DES CRIPT IO NS
SECTION OF THIS DATA SHEET.
COPLANARITY
0.08
02-05-2013-C
TOP VIEW BOTTOM VIEW
0.20 M IN
Figure 40. 10-Lead Lead Frame Chip Scale Package [LFCSP_WD]
3 mm × 3 mm Body, Very Very Thin, Dual Lead
(CP-10-9)
Dimensions shown in millimeters
COMPLIANTTO JEDEC STANDARDS MO-187-BA
091709-A
6°
0°
0.70
0.55
0.40
5
10
1
6
0.50BSC
0.30
0.15
1.10 MAX
3.10
3.00
2.90
COPLANARITY
0.10
0.23
0.13
3.10
3.00
2.90
5.15
4.90
4.65
PIN 1
IDENTIFIER
15° MAX
0.95
0.85
0.75
0.15
0.05
Figure 41. 10-Lead Mini Small Outline Package [MSOP]
(RM-10)
Dimensions shown in millimeters
ORDERING GUIDE
Model1
Temperature
Range
Power-On
Reset Code Accuracy
Package
Description
Package
Option Branding
AD5663ARMZ −40°C to +105°C Zero ±16 LSB INL 10-Lead MSOP RM-10 D80
AD5663ARMZ-REEL7 −40°C to +105°C Zero ±16 LSB INL 10-Lead MSOP RM-10 D80
AD5663BRMZ −40°C to +105°C Zero ±12 LSB INL 10-Lead MSOP RM-10 D8C
AD5663BRMZ-REEL7 −40°C to +105°C Zero ±12 LSB INL 10-Lead MSOP RM-10 D8C
AD5663BRMZ-1
−40°C to +105°C
Midscale
±12 LSB INL
10-Lead MSOP
RM-10
D7J
AD5663BRMZ-1REEL7 −40°C to +105°C Midscale ±12 LSB INL 10-Lead MSOP RM-10 D7J
AD5663BCPZ-R2 −40°C to +105°C Zero ±12 LSB INL 10-Lead LFCSP_WD CP-10-9 D8C
AD5663BCPZ-REEL7 −40°C to +105°C Zero ±12 LSB INL 10-Lead LFCSP_WD CP-10-9 D8C
1 Z = RoHS Compliant Part.
AD5663 Data Sheet
Rev. A | Page 22 of 24
NOTES
Data Sheet AD5663
Rev. A | Page 23 of 24
NOTES
