AD AD5531BRU-REEL Serial input, voltage output 12-/14-bit digital-to-analog converter Datasheet

Serial Input, Voltage Output
12-/14-Bit Digital-to-Analog Converters
AD5530/AD5531
FUNCTIONAL BLOCK DIAGRAM
Pin-compatible 12-, 14-bit digital-to-analog converters
Serial input, voltage output
Maximum output voltage range of ±10 V
Data readback
3-wire serial interface
Clear function to a user-defined voltage
Power-down function
Serial data output for daisy-chaining
16-lead TSSOP
APPLICATIONS
Industrial automation
Automatic test equipment
Process control
General-purpose instrumentation
VSS
VDD
AD5530/AD5531
REFIN
R
12-/14-BIT
DAC
R
VOUT
R
REFAGND
R
LDAC
DUTGND
DAC REGISTER
RBEN
CLR
SDIN
POWER-DOWN
CONTROL LOGIC
SHIFT REGISTER
GND
SCLK
SYNC
PD
SDO
00938-001
FEATURES
Figure 1.
GENERAL DESCRIPTION
The AD5530/AD5531 are single 12- and 14-bit (respectively)
serial input, voltage output digital-to-analog converters (DAC).
They utilize a versatile 3-wire interface that is compatible with
SPI®, QSPI™, MICROWIRE™, and DSP interface standards. Data
is presented to the part in a 16-bit serial word format. Serial
data is available on the SDO pin for daisy-chaining purposes.
Data readback allows the user to read the contents of the DAC
register via the SDO pin.
The DAC output is buffered by a gain of two amplifier and
referenced to the potential at DUTGND. LDAC can be used to
update the output of the DAC asynchronously. A power-down
pin (PD) allows the DAC to be put into a low power state, and
a CLR pin allows the output to be cleared to a user-defined
voltage, the potential at DUTGND.
The AD5530/AD5531 are available in 16-lead TSSOP.
Rev. B
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.
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Fax: 781.461.3113
©2007 Analog Devices, Inc. All rights reserved.
AD5530/AD5531
TABLE OF CONTENTS
Features .............................................................................................. 1
PD Function................................................................................ 13
Applications....................................................................................... 1
Readback Function .................................................................... 13
Functional Block Diagram .............................................................. 1
CLR Function.............................................................................. 13
General Description ......................................................................... 1
Output Voltage............................................................................ 14
Revision History ............................................................................... 2
Bipolar Configuration................................................................ 14
Specifications..................................................................................... 3
Microprocessor Interfacing........................................................... 15
AC Performance Characteristics ................................................ 5
AD5530/AD5531 to ADSP-21xx.............................................. 15
Standalone Timing Characteristics............................................ 5
AD5530/AD5531 to 8051 Interface ......................................... 15
Daisy-Chaining and Readback Timing Characteristics.......... 6
AD5530/AD5531 to MC68HC11 Interface ............................ 15
Absolute Maximum Ratings............................................................ 7
Applications Information .............................................................. 17
ESD Caution.................................................................................. 7
Optocoupler Interface................................................................ 17
Pin Configuration and Function Descriptions............................. 8
Serial Interface to Multiple AD5530s or AD5531s ................ 17
Typical Performance Characteristics ............................................. 9
Terminology .................................................................................... 12
Daisy-Chaining Interface with Multiple AD5530s or
AD5531s ...................................................................................... 17
Theory of Operation ...................................................................... 13
Outline Dimensions ....................................................................... 18
DAC Architecture....................................................................... 13
Ordering Guide .......................................................................... 18
Serial Interface ............................................................................ 13
REVISION HISTORY
1/07—Rev. A to Rev. B
Updated Format..................................................................Universal
Changes to Figure 28...................................................................... 17
3/06—Rev. 0 to Rev. A
Change to Table 3 ............................................................................. 5
Change to Figure 4 ........................................................................... 8
Change to Output Voltage Section............................................... 14
Change to Ordering Guide............................................................ 18
5/02—Revision 0: Initial Version
Rev. B | Page 2 of 20
AD5530/AD5531
SPECIFICATIONS
VDD = 15 V ± 10%; VSS = −15 V ± 10%; GND = 0 V; RL = 5 kΩ and CL = 220 pF to GND. All specifications TMIN to TMAX, unless otherwise noted.
Table 1.
Parameter 1
ACCURACY
Resolution
Relative Accuracy
Differential Nonlinearity
Zero-Scale Error
Full-Scale Error
Gain Error
Gain Temperature Coefficient 2
REFERENCE INPUTS2
Reference Input Range
DC Input Resistance
Input Current
DUTGND INPUT2
DC Input Impedance
Max Input Current
Input Range
O/P CHARACTERISTICS2
Output Voltage Swing
Short-Circuit Current
Resistive Load
Capacitive Load
DC Output Impedance
DIGITAL I/O
VINH, Input High Voltage
VINL, Input Low Voltage
IINH, Input Current
CIN, Input Capacitance2
SDO VOL, Output Low Voltage
POWER REQUIREMENTS
VDD/VSS
Power Supply Sensitivity
ΔFull Scale/ΔVDD
ΔFull Scale/ΔVSS
IDD
ISS
IDD in Power-Down
1
2
AD5530
AD5531
Unit
12
±1
±1
±2
±2
±1
0.5
10
14
±2
±1
±8
±8
±4
0.5
10
Bits
LSB max
LSB max
LSB max
LSB max
LSB typ
ppm FSR/°C typ
ppm FSR/°C max
0 to 5
100
±1
0 to 5
100
±1
V min to V max
MΩ typ
μA max
Per input, typically ±20 nA
60
±0.3
−4 to +4
60
±0.3
−4 to +4
kΩ typ
mA typ
V min to V max
Max output range ±10 V
±10
15
5
1200
0.5
±10
15
5
1200
0.5
V max
mA max
kΩ min
pF max
Ω max
2.4
0.8
±10
10
0.4
2.4
0.8
±10
10
0.4
V min
V max
μA max
pF max
V max
Total for all pins
3 pF typical
ISINK = 1 mA
+15/−15
+15/−15
V nom
±10% for specified performance
110
100
2
2
150
110
100
2
2
150
dB typ
dB typ
mA max
mA max
μA max
Outputs unloaded
Outputs unloaded
Typically 50 μA
Temperature range for B Version: −40°C to +85°C.
Guaranteed by design, not subject to production test.
Rev. B | Page 3 of 20
Test Conditions/Comments
Guaranteed monotonic over temperature
Typically within ±1 LSB
Typically within ±1 LSB
Max output range ±10 V
To 0 V
To 0 V
AD5530/AD5531
VDD = 12 V ± 10%; VSS = −12 V ± 10%; GND = 0 V; RL = 5 kΩ and CL = 220 pF to GND; TA = TMIN to TMAX, unless otherwise noted.
Table 2.
Parameter 1
ACCURACY
Resolution
Relative Accuracy
Differential Nonlinearity
Zero-Scale Error
Full-Scale Error
Gain Error
Gain Temperature Coefficient 2
REFERENCE INPUTS2
Reference Input Range
DC Input Resistance
Input Current
DUTGND INPUT2
DC Input Impedance
Max Input Current
Input Range
O/P CHARACTERISTICS2
Output Voltage Swing
Short-Circuit Current
Resistive Load
Capacitive Load
DC Output Impedance
DIGITAL I/O
VINH, Input High Voltage
VINL, Input Low Voltage
IINH, Input Current
CIN, Input Capacitance2
SDO VOL, Output Low Voltage
POWER REQUIREMENTS
VDD/VSS
Power Supply Sensitivity
ΔFull Scale/ΔVDD
ΔFull Scale/ΔVSS
IDD
ISS
IDD in Power-Down
1
2
AD5530
AD5531
Unit
12
±1
±1
±2
±2
±1
0.5
10
14
±2
±1
±8
±8
±4
0.5
10
Bits
LSB max
LSB max
LSB max
LSB max
LSB typ
ppm FSR/°C typ
ppm FSR/°C max
0 to 4.096
100
±1
0 to 4.096
100
±1
V min to V max
MΩ typ
μA max
Per input, typically ±20 nA
60
±0.3
−3 to +3
60
±0.3
−3 to +3
kΩ typ
mA typ
V min to V max
Max output range ±8.192 V
±8.192
15
5
1200
0.5
±8.192
15
5
1200
0.5
V max
mA max
kΩ min
pF max
Ω max
2.4
0.8
±10
10
0.4
2.4
0.8
±10
10
0.4
V min
V max
μA max
pF max
V max
Total for all pins
3 pF typical
ISINK = 1 mA
+12/−12
+12/−12
V nom
±10% for specified performance
110
100
2
2
150
110
100
2
2
150
dB typ
dB typ
mA max
mA max
μA max
Outputs unloaded
Outputs unloaded
Typically 50 μA
Temperature range for B Version: −40°C to +85°C.
Guaranteed by design, not subject to production test.
Rev. B | Page 4 of 20
Test Conditions/Comments
Guaranteed monotonic over temperature
Typically within ±1 LSB
Typically within ±1 LSB
Max output range ±8.192 V
To 0 V
To 0 V
AD5530/AD5531
AC PERFORMANCE CHARACTERISTICS
VDD = 10.8 V to 16.5 V, VSS = −10.8 V to −16.5 V; GND = 0 V; RL = 5 kΩ and CL = 220 pF to GND. All specifications TMIN to TMAX, unless
otherwise noted.
Table 3.
Parameter
DYNAMIC PERFORMANCE
Output Voltage Settling Time
B Version
Unit
Test Conditions/Comments
20
μs typ
Full-scale change to ±½ LSB. DAC latch contents alternately
loaded with all 0s and all 1s.
Slew Rate
Digital-to-Analog Glitch Impulse
1.3
120
V/μs typ
nV-s typ
Digital Feedthrough
Output Noise Spectral Density @ 1 kHz
0.5
100
nV-s typ
nV/√Hz typ
DAC latch alternately loaded with 0x0FFF and 0x1000. Not
dependent on load conditions.
Effect of input bus activity on DAC output under test.
All 1s loaded to DAC.
STANDALONE TIMING CHARACTERISTICS
VDD = 10.8 V to 16.5 V, VSS = −10.8 V to −16.5 V; GND = 0 V; RL = 5 kΩ and CL = 220 pF to GND. All specifications TMIN to TMAX, unless
otherwise noted.
Table 4.
Parameter 1, 2
fMAX
t1
t2
t3
t4
t5
t6
t7
t8
t9
t10
t11
t12
2
Unit
MHz max
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
Description
SCLK frequency
SCLK cycle time
SCLK low time
SCLK high time
SYNC to SCLK falling edge setup time
SCLK falling edge to SYNC rising edge
Min SYNC high time
Data setup time
Data hold time
SYNC high to LDAC low
LDAC pulse width
LDAC high to SYNC low
CLR pulse width
Guaranteed by design, not subject to production test.
Sample tested during initial release and after any redesign or process change that can affect this parameter. All input signals are measured with tR = tF = 5 ns (10% to
90% of VDD) and timed from a voltage level of (VIL + VIH)/2.
t1
t3
SCLK
t4
SYNC
t2
t5
t6
t7
MSB
SDIN
DB15
DB14
t8
LSB
DB11
DB0
t9
LDAC1
t11
t10
t12
CLR
1LDAC
00938-002
1
Limit at TMIN, TMAX
7
140
60
60
50
40
50
40
15
5
50
5
50
CAN BE TIED PERMANENTLY LOW, IF REQUIRED.
Figure 2. Timing Diagram for Standalone Mode
Rev. B | Page 5 of 20
AD5530/AD5531
DAISY-CHAINING AND READBACK TIMING CHARACTERISTICS
VDD = 10.8 V to 16.5 V, VSS = −10.8 V to −16.5 V; GND = 0 V; RL = 5 kΩ and CL = 220 pF to GND. All specifications TMIN to TMAX, unless
otherwise noted.
Table 5.
Parameter 1, 2, 3
fMAX
t1
t2
t3
t4
t5
t6
t7
t8
t12
t13
t14
t15
t16
t17
Limit at TMIN, TMAX
2
500
200
200
50
40
50
40
15
50
130
50
50
50
100
Unit
MHz max
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns max
ns min
ns min
ns min
Description
SCLK frequency
SCLK cycle time
SCLK low time
SCLK high time
SYNC to SCLK falling edge setup time
SCLK falling edge to SYNC rising edge
Min SYNC high time
Data setup time
Data hold time
CLR pulse width
SCLK falling edge to SDO valid
SCLK falling edge to SDO invalid
RBEN to SCLK falling edge setup time
RBEN hold time
RBEN falling edge to SDO valid
1
Guaranteed by design, not subject to production test.
Sample tested during initial release and after any redesign or process change that can affect this parameter. All input signals are measured with tR = tF = 5 ns (10% to
90% of VDD) and timed from a voltage level of (VIL + VIH)/2.
3
SDO; RPULLUP = 5 kΩ, CL = 15 pF
2
t1
t3
SCLK
t4
t6
t7
MSB
SDIN
DB15
DB14
t8
DB11
LSB
DB0
t13
SDO
(DAISYCHAINING)
t14
MSB
DB15
LSB
DB11
DB0
t15
t16
RBEN
t13
t17
SDO
(READBACK)
0
MSB
Figure 3. Timing Diagram for Daisy-Chaining and Readback Mode
Rev. B | Page 6 of 20
t14
0
RB13
RB0
LSB
00938-003
SYNC
t2
t5
AD5530/AD5531
ABSOLUTE MAXIMUM RATINGS
TA = 25°C, unless otherwise noted.
Table 6.
Parameter
VDD to GND
VSS to GND
Digital Inputs to GND
SDO to GND
REFIN to REFAGND
REFIN to GND
REFAGND to GND
DUTGND to GND
Operating Temperature Range
Industrial (B Version)
Storage Temperature Range
Maximum Junction Temperature (TJ MAX)
Package Power Dissipation
Thermal Impedance θJA
TSSOP (RU-16)
Lead Temperature (Soldering 10 sec)
IR Reflow, Peak Temperature (<20 sec)
Rating
−0.3 V to +17 V
+0.3 V to −17 V
−0.3 V to VDD + 0.3 V
−0.3 V to +6.5 V
−0.3 V to +17 V
VSS − 0.3 V to VDD + 0.3 V
VSS − 0.3 V to VDD + 0.3 V
VSS − 0.3 V to VDD + 0.3 V
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.
ESD CAUTION
−40°C to +85°C
−65°C to +150°C
150°C
(TJ MAX – TA)/θJA
150.4°C/W
300°C
235°C
Rev. B | Page 7 of 20
AD5530/AD5531
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
1
16
VDD
REFIN
2
15
VOUT
LDAC
3
14
DUTGND
SDIN
4
13
VSS
AD5530/
AD5531
TOP VIEW
(Not to Scale)
SYNC
5
12
NC
RBEN
6
11
GND
SCLK
7
10
PD
SDO
8
9
CLR
NC = NO CONNECT
00938-004
REFAGND
Figure 4. Pin Configuration
Table 7. Pin Function Descriptions
Pin No.
1
2
3
Mnemonic
REFAGND
REFIN
LDAC
4
5
6
SDIN
SYNC
RBEN
7
8
SCLK
SDO
9
CLR
10
11
12
13
14
15
16
PD
GND
NC
VSS
DUTGND
VOUT
VDD
Description
For bipolar ±10 V output range, this pin should be tied to 0 V.
This is the voltage reference input for the DAC. Connect to external 5 V reference for specified bipolar ±10 V output.
Load DAC Logic Input (Active Low). When taken low, the contents of the shift register are transferred to the DAC
register. LDAC can be tied permanently low, enabling the outputs to be updated on the rising edge of SYNC.
Serial Data Input. This device accepts 16-bit words. Data is clocked into the input register on the falling edge of SCLK.
Active Low Control Input. Data is clocked into the shift register on the falling edges of SCLK.
Active Low Readback Enable Function. This function allows the contents of the DAC register to be read. Data
from the DAC register is shifted out on the SDO pin on each rising edge of SCLK.
Clock Input. Data is clocked into the input register on the falling edge of SCLK.
Serial Data Out. This pin is used to clock out the serial data previously written to the input shift register or can be
used in conjunction with RBEN to read back the data from the DAC register. This is an open drain output; it
should be pulled high with an external pull-up resistor. In standalone mode, SDO should be tied to GND or left
high impedance.
Level Sensitive, Active Low Input. A falling edge of CLR resets VOUT to DUTGND. The contents of the registers
are untouched.
This allows the DAC to be put into a power-down state.
Ground Reference.
Do not connect anything to this pin.
Negative Analog Supply Voltage. −12 V ± 10% or −15 V ± 10%, for specified performance.
VOUT is referenced to the voltage applied to this pin.
DAC Output.
Positive Analog Supply Voltage. 12 V ± 10% or 15 V ± 10%, for specified performance.
Rev. B | Page 8 of 20
AD5530/AD5531
TYPICAL PERFORMANCE CHARACTERISTICS
1.0
1.00
VDD = +15V
VSS = –15V
REFIN = +5V
REFAGND = 0V
TA = 25°C
0.8
0.6
VDD = +15V
VSS = –15V
REFIN = +5V
REFAGND = 0V
TA = 25°C
0.75
0.50
0.4
0.25
LSB
LSB
0.2
0
–0.2
0
–0.25
–0.4
–0.50
–0.6
0
500
1000
1500
2000
2500
3000
3500
–1.00
4000
00938-008
–1.0
–0.75
00938-005
–0.8
0
2000
4000
6000
CODE
Figure 8. AD5531 Typical DNL Plot
2.0
VDD = +15V
VSS = –15V
REFIN = +5V
REFAGND = 0V
TA = 25°C
0.4
0.3
10000 12000 14000 16000
CODE
Figure 5. AD5530 Typical INL Plot
0.5
8000
1.5
VDD = +15V
VSS = –15V
REFIN = +5V
REFAGND = 0V
1.0
ERROR (LSB)
0.2
LSB
0.1
0
–0.1
0.5
0
–0.5
–0.2
–1.0
–0.3
0
500
1000
1500
2000
2500
3000
3500
–2.0
–40
4000
00938-009
–0.5
–1.5
00938-006
–0.4
–20
0
CODE
Figure 6. AD5530 Typical DNL Plot
VDD = +15V
VSS = –15V
REFIN = +5V
REFAGND = 0V
TA = 25°C
1.5
0.8
0.6
0
–0.5
80
VDD = +15V
VSS = –15V
REFIN = +5V
REFAGND = 0V
0.2
0
–0.2
–0.4
–1.0
–1.5
0
2000
4000
6000
8000
00938-010
–0.6
–0.8
00938-007
LSB
0.5
–2.0
60
0.4
ERROR (LSB)
1.0
40
Figure 9. AD5531 Typical INL Error vs. Temperature
1.0
2.0
20
TEMPERATURE (°C)
–1.0
–40
10000 12000 14000 16000
–20
0
20
40
60
TEMPERATURE (°C)
CODE
Figure 10. AD5531 Typical DNL Error vs. Temperature
Figure 7. AD5531 Typical INL Plot
Rev. B | Page 9 of 20
80
AD5530/AD5531
3
0.03
VDD = +15V
VSS = –15V
REFIN = 0V
TA = 25°C
2
POSITIVE INL
–40°C
0.02
IDD (mA)
ERROR (LSB)
1
0
NEGATIVE INL
+25°C
+85°C
0.01
–1
2.5
3.0
3.5
4.0
4.5
5.0
5.5
0
10
6.0
00938-014
–3
2.0
00938-011
–2
11
12
REFIN VOLTAGE (V)
13
14
15
16
17
SUPPLY VOLTAGE (V)
Figure 11. AD5531 Typical INL Error vs. Reference Voltage
Figure 14. IDD in Power-Down vs. Supply
0
12
VDD = +15V
VSS = –15V
REFIN = +5V
REFAGND = 0V
–0.5
8
VOUT (V)
ERROR (LSB)
4
–1.0
–1.5
0
–4
00938-012
–2.5
–40
–20
0
20
40
60
–12
80
TEMPERATURE (°C)
0
5
10
15
20
25
TIME (µs)
Figure 12. Typical Full-Scale and Offset Error vs. Temperature
Figure 15. Settling Time
1.50
0
–0.02
1.45
+85°C
–0.04
1.40
–0.06
VOUT (V)
+25°C
1.35
–40°C
–0.08
–0.10
–0.12
VDD = +15V
VSS = –15V
REFIN = +5V
REFAGND = 0V
TA = 25°C
1.25
1.20
10
11
12
13
14
15
16
17
VDD/VSS (V)
–0.14
–0.16
TIME (750ns/DIV)
Figure 13. IDD vs. VDD/VSS
Figure 16. Typical Digital-to-Analog Glitch Impulse
Rev. B | Page 10 of 20
00938-016
1.30
00938-013
CURRENT (mA)
VDD = +15V
VSS = –15V
REFIN = +5V
REFAGND = 0V
TA = 25°C
–8
00938-015
–2.0
AD5530/AD5531
VOUT
VDD = +15V
VSS = –15V
REFIN = +5V
REFAGND = 0V
TA = 25°C
PD
2V/DIV
00938-017
2V/DIV
Figure 17. Typical Power-Down Time
Rev. B | Page 11 of 20
AD5530/AD5531
TERMINOLOGY
Relative Accuracy
Relative accuracy or endpoint linearity is a measure of the
maximum deviation, in LSBs, from a straight line passing
through the endpoints of the DAC transfer function.
Gain Error
Gain error is the difference between the actual and ideal analog
output range, expressed as a percent of the full-scale range. It is
the deviation in slope of the DAC transfer characteristic from ideal.
Differential Nonlinearity
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.
Output Voltage Settling Time
This is the amount of time it takes for the output to settle to a
specified level for a full-scale input change.
Zero-Scale Error
Zero-scale error is a measure of the output error when all 0s are
loaded to the DAC latch.
Full-Scale Error
This is the error in DAC output voltage when all 1s are loaded
into the DAC latch. Ideally the output voltage, with all 1s loaded
into the DAC latch, should be 2 VREF − 1 LSB.
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 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.
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 is measured with a full-scale code
change on the data bus, that is, from all 0s to all 1s and vice versa.
Rev. B | Page 12 of 20
AD5530/AD5531
THEORY OF OPERATION
DAC ARCHITECTURE
REFIN
The AD5530/AD5531 are pin-compatible 12- and 14-bit DACs.
The AD5530 consists of a straight 12-bit R-2R voltage mode
DAC, and the AD5531 consists of a 14-bit R-2R section. Using a
5 V reference connected to the REFIN pin and REFAGND tied
to 0 V, a bipolar ±10 V voltage output results. The DAC coding
is straight binary.
LDAC
DAC REGISTER
14
SYNC REGISTER
SYNC
DB0 (LSB)
D6 D5
D4 D3 D2 D1 D0 X X
DATA BITS
00938-018
DB15 (MSB)
00938-019
DATA BITS
SDO
Figure 20. Simplified Serial Interface
Data written to the part via SDIN is available on the SDO pin 16
clocks later if the readback function is not used. SDO data is
clocked out on the falling edge of the serial clock with some delay.
The PD pin allows the user to place the device into power-down
mode. While in this mode, power consumption is at a minimum;
the device draws only 50 μA of current. The PD function does
not affect the contents of the DAC register.
DB0 (LSB)
X X D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
16-BIT SHIFT
REGISTER
SDIN
PD FUNCTION
Figure 18. AD5530 Input Shift Register Contents
DB15 (MSB)
14
00938-020
Serial data on the SDIN input is loaded to the input register
under the control of SCLK, SYNC, and LDAC. A write
operation transfers a 16-bit word to the AD5530/AD5531.
Figure 2 and Figure 3 show the timing diagrams. Figure 18 and
Figure 19 show the contents of the input shift register. Twelve or
14 bits of the serial word are data bits; the rest are don’t cares.
OUTPUT
14
SERIAL INTERFACE
X X D11 D10 D9 D8 D7
12-/14-BIT DAC
Figure 19. AD5531 Input Shift Register Contents
The serial word is framed by the signal, SYNC. After a high-tolow transition on SYNC, data is latched into the input shift
register on the falling edges of SCLK. There are two ways the
DAC register and output can be updated. The LDAC signal is
examined on the falling edge of SYNC; depending on its status,
either a synchronous or asynchronous update is selected. If
LDAC is low, then the DAC register and output are updated on
the low-to-high transition of SYNC. Alternatively, if LDAC is
high upon sampling, the DAC register is not loaded with the
new data on a rising edge of SYNC. The contents of the DAC
register and the output voltage are updated by bringing LDAC
low any time after the 16-bit data transfer is complete. LDAC
can be tied permanently low if required. A simplified diagram
of the input loading circuitry is illustrated in Figure 20.
READBACK FUNCTION
The AD5530/AD5531 allows the data contained in the DAC
register to be read back if required. The pins involved are the
RBEN and SDO (serial data out). When RBEN is taken low, on
the next falling edge of SCLK, the contents of the DAC register
are transferred to the shift register. RBEN can be used to frame
the readback data by leaving it low for 16 clock cycles, or it can
be asserted high after the required hold time. The shift register
contains the DAC register data and this is shifted out on the
SDO line on each falling edge of SCLK with some delay. This
ensures the data on the serial data output pin is valid for the
falling edge of the receiving part. The two MSBs of the 16-bit
word are 0s.
CLR FUNCTION
The falling edge of CLR causes VOUT to be reset to the same
potential as DUTGND. The contents of the registers remain
unchanged, so the user can reload the previous data with LDAC
after CLR is asserted high. Alternatively, if LDAC is tied low, the
output is loaded with the contents of the DAC register automatically after CLR is brought high.
Rev. B | Page 13 of 20
AD5530/AD5531
+15V
OUTPUT VOLTAGE
The DAC transfer function is as follows:
2
D
VOUT = 2 × [2 × ((REFIN − REFAGND) × N ) + 2 ×
2
REFAGND − REFIN] − DUTGND
6
REFIN
9
AD586
C1
1µF
where:
5
R1
10kΩ
4
VOUT
AD5530/
AD55311
DUTGND
REFAGND
D is the decimal data-word loaded to the DAC register.
N is the resolution of the DAC.
GND
VSS
SIGNAL
GND
BIPOLAR CONFIGURATION
VOUT
(–10V TO +10V)
VOUT
SIGNAL
GND
1ADDITIONAL
00938-021
–15V
PINS OMITTED FOR CLARITY.
Figure 21. Bipolar ±10 V Operation
2 REFIN
DAC OUTPUT VOLTAGE
Figure 21 shows the AD5530/AD5531 in a bipolar circuit
configuration. REFIN is driven by the AD586, 5 V reference,
and the REFAGND and DUTGND pins are tied to GND. This
results in a bipolar output voltage ranging from −10 V to +10 V.
Resistor R1 is provided (if required) for gain adjust. Figure 22
shows the transfer function of the DAC when REFAGND is tied
to 0 V.
0V
DAC INPUT CODE
000 001
(3)FFF
Figure 22. Output Voltage vs. DAC Input Codes (Hex)
Rev. B | Page 14 of 20
00938-022
–2 REFIN
AD5530/AD5531
MICROPROCESSOR INTERFACING
The 8051 provides the LSB of its SBUF register as the first bit in
the data stream. The user has to ensure that the data in the SBUF
register is arranged correctly because the DAC expects MSB first.
For all the interfaces, the DAC output update can be done
automatically when all the data is clocked in or asynchronously
under the control of LDAC.
The contents of the DAC register can be read using the
readback function. RBEN is used to frame the readback data,
which is clocked out on SDO. Figure 23, Figure 24, and Figure 25
show these DACs interfacing with a simple 4-wire interface.
The serial interface of the AD5530/AD5531 can be operated
from a minimum of three wires.
AD5530/AD5531 TO ADSP-21xx
An interface between the AD5530/AD5531 and the ADSP-21xx
is shown in Figure 23. In the interface example shown, SPORT0
is used to transfer data to the DAC. The SPORT control register
should be configured as follows: internal clock operation,
alternate framing mode; active low framing signal.
Transmission is initiated by writing a word to the Tx register
after the SPORT has been enabled. As the data is clocked out of
the DSP on the rising edge of SCLK, no glue logic is required to
interface the DSP to the DAC. In the interface shown, the DAC
output is updated using the LDAC pin via the DSP. Alternatively,
the LDAC input could be tied permanently low and then the
update takes place automatically when TFS is taken high.
FO
TFS
DT
SCLK
LDAC
P3.3
SYNC
RxD
SDIN
TxD
SCLK
Figure 24. AD5530/AD5531 to 8051 Interface
When data is to be transmitted to the DAC, P3.3 is taken low.
Data on RxD is clocked out of the microcontroller on the rising
edge of TxD and is valid on the falling edge. As a result no glue
logic is required between this DAC and microcontroller interface.
The 8051 transmits data in 8-bit bytes with only eight falling
clock edges occurring in the transmit cycle. As the DAC expects
a 16-bit word, P3.3 must be left low after the first 8 bits are
transferred. After the second byte has been transferred, the P3.3
line is taken high. The DAC can be updated using LDAC via
P3.4 of the 8051.
AD5530/AD5531 TO MC68HC11 INTERFACE
Figure 25 shows an example of a serial interface between the
AD5530/AD5531 and the MC68HC11 microcontroller. SCK of
the MC68HC11 drives the SCLK of the DAC, and the MOSI
output drives the serial data lines, SDIN. SYNC is driven from
one of the port lines, in this case PC7.
MC68HC111
AD5530/
AD55311
LDAC
SYNC
SDIN
SCLK
1ADDITIONAL PINS OMITTED FOR CLARITY.
P3.4
1ADDITIONAL PINS OMITTED FOR CLARITY.
AD5530/
AD55311
PC6
LDAC
PC7
SYNC
MOSI
SDIN
SCK
SCLK
1ADDITIONAL PINS OMITTED FOR CLARITY.
00938-023
ADSP-2101/
ADSP-21031
AD5530/
AD55311
00938-024
80C51/80L511
00938-025
Microprocessor interfacing to the AD5530/AD5531 is via a
serial bus that uses standard protocol compatible with microcontrollers and DSP processors. The communications channel
is a 3-wire (minimum) interface consisting of a clock signal, a
data signal, and a synchronization signal. The AD5530/AD5531
requires a 16-bit data-word with data valid on the falling edge
of SCLK.
Figure 25. AD5530/AD5531 to MC68HC11 Interface
Figure 23. AD5530/AD5531 to ADSP-21xx Interface
AD5530/AD5531 TO 8051 INTERFACE
A serial interface between the AD5530/AD5531 and the 8051 is
shown in Figure 24. TxD of the 8051 drives SCLK of the
AD5530/AD5531, while RxD drives the serial data line, SDIN.
P3.3 and P3.4 are bit-programmable pins on the serial port and
are used to drive SYNC and LDAC, respectively.
The MC68HC11 is configured for master mode, MSTR = 1,
CPOL = 0, and CPHA = 1. When data is transferred to the part,
PC7 is taken low and data is transmitted MSB first. Data
appearing on the MOSI output is valid on the falling edge of SCK.
Eight falling clock edges occur in the transmit cycle, so to load the
required 16-bit word, PC7 is not brought high until the second
8-bit word has been transferred to the DAC input shift register.
Rev. B | Page 15 of 20
AD5530/AD5531
LDAC is controlled by the PC6 port output. The DAC can be
updated after each 2-byte transfer by bringing LDAC low. This
example does not show other serial lines for the DAC. If CLR
were used, it could be controlled by port output PC5. To read
data back from the DAC register, the SDO line can be
connected to MISO of the MC68HC11, with RBEN tied to
another port output controlling and framing the readback
data transfer.
Rev. B | Page 16 of 20
AD5530/AD5531
APPLICATIONS INFORMATION
OPTOCOUPLER INTERFACE
In many process control applications, it is necessary to provide
an isolation barrier between the controller and the unit being
controlled. Opto-isolators can provide voltage isolation in
excess of 3 kV. The serial loading structure of the AD5530/
AD5531 makes it ideal for opto-isolated interfaces because the
number of interface lines is kept to a minimum. Figure 26
shows a 4-channel isolated interface to the AD5530/AD5531.
To reduce the number of opto-isolators, if simultaneous
updating is not required, then the LDAC pin can be tied
permanently low.
SERIAL INTERFACE TO MULTIPLE AD5530s OR
AD5531s
Figure 27 shows how the SYNC pin is used to address multiple
AD5530/AD5531s. All devices receive the same serial clock and
serial data, but only one device receives the SYNC signal at any
one time. The DAC addressed is determined by the decoder.
There is some feedthrough from the digital input lines, the
effects of which can be minimized by using a burst clock.
AD5530/AD55311
SCLK
SYNC
VCC
SDIN
SDIN
VCC
µCONTROLLER
CONTROL OUT
TO LDAC
ENABLE
SYNC OUT
SERIAL CLOCK OUT
AD5530/AD55311
EN
SYNC
DECODER1
TO SYNC
CODED
ADDRESS
VOUT
SCLK
SDIN
DGND
VOUT
SCLK
TO SCLK
AD5530/AD55311
1 ADDITIONAL PINS
OMITTED FOR CLARITY.
SERIAL DATA OUT
SYNC
TO SDIN
SDIN
VOUT
00938-026
SCLK
OPTOCOUPLER
AD5530/AD55311
Figure 26. Opto-Isolated Interface
SDIN
VOUT
SCLK
Figure 27. Addressing Multiple AD5530/AD5531s
DAISY-CHAINING INTERFACE WITH MULTIPLE AD5530s OR AD5531s
A number of these DAC parts can be daisy-chained together using the SDO pin. Figure 28 illustrates such a configuration.
VDD
R
R
R
AD5530/AD55311
AD5530/AD55311
AD5530/AD55311
SCLK
SCLK
SCLK
SCLK
SDIN
SDIN
SYNC
SYNC
SDIN
SDO
SYNC
SDIN
SYNC
SDO
TO OTHER
SERIAL DEVICES
00938-028
1 ADDITIONAL
SDO
PINS OMITTED FOR CLARITY.
Figure 28. Daisy-Chaining Multiple AD5530/AD5531s
Rev. B | Page 17 of 20
00938-027
SYNC
AD5530/AD5531
OUTLINE DIMENSIONS
5.10
5.00
4.90
16
9
4.50
4.40
4.30
6.40
BSC
1
8
PIN 1
1.20
MAX
0.15
0.05
0.65
BSC
0.30
0.19
0.20
0.09
SEATING
PLANE
COPLANARITY
0.10
0.75
0.60
0.45
8°
0°
COMPLIANT TO JEDEC STANDARDS MO-153-AB
Figure 29. 16-Lead Thin Shrink Small Outline Package (TSSOP)
(RU-16)
Dimensions shown in millimeters
ORDERING GUIDE
Model
AD5530BRU
AD5530BRU-REEL
AD5530BRU-REEL7
AD5530BRUZ 1
AD5530BRUZ-REEL1
AD5530BRUZ-REEL71
AD5531BRU
AD5531BRU-REEL
AD5531BRU-REEL7
AD5531BRUZ1
AD5531BRUZ-REEL1
AD5531BRUZ-REEL71
1
Temperature Range
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
Resolution
12
12
12
12
12
12
14
14
14
14
14
14
INL (LSBs)
±1
±1
±1
±1
±1
±1
±2
±2
±2
±2
±2
±2
Z = Pb-free part.
Rev. B | Page 18 of 20
DNL (LSBs)
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
±1
Package Description
16-Lead TSSOP
16-Lead TSSOP
16-Lead TSSOP
16-Lead TSSOP
16-Lead TSSOP
16-Lead TSSOP
16-Lead TSSOP
16-Lead TSSOP
16-Lead TSSOP
16-Lead TSSOP
16-Lead TSSOP
16-Lead TSSOP
Package Option
RU-16
RU-16
RU-16
RU-16
RU-16
RU-16
RU-16
RU-16
RU-16
RU-16
RU-16
RU-16
AD5530/AD5531
NOTES
Rev. B | Page 19 of 20
AD5530/AD5531
NOTES
©2007 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
C00938-0-1/07(B)
Rev. B | Page 20 of 20
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