EVAL-AD5429EBZ [ADI]

Dual 8-/10-/12-Bit, High Bandwidth, Multiplying DACs with Serial Interface; 双8位/ 10位/ 12位,高带宽,乘法DAC,串行接口
EVAL-AD5429EBZ
型号: EVAL-AD5429EBZ
厂家: ADI    ADI
描述:

Dual 8-/10-/12-Bit, High Bandwidth, Multiplying DACs with Serial Interface
双8位/ 10位/ 12位,高带宽,乘法DAC,串行接口

文件: 总32页 (文件大小:619K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
Dual 8-/10-/12-Bit, High Bandwidth,  
Multiplying DACs with Serial Interface  
AD5429/AD5439/AD5449  
GENERAL DESCRIPTION  
FEATURES  
The AD5429/AD5439/AD54491 are CMOS, 8-, 10-, and 12-bit,  
dual-channel, current output digital-to-analog converters (DAC),  
respectively. These devices operate from a 2.5 V to 5.5 V power  
supply, making them suited to battery-powered and other  
applications.  
10 MHz multiplying bandwidth  
INL of 0.2ꢀ LSB ꢁ 8 bits  
16-lead TSSOP package  
2.ꢀ V to ꢀ.ꢀ V supply operation  
10 V reference input  
ꢀ0 MHz serial interface  
As a result of being manufactured on a CMOS submicron process,  
these parts offer excellent 4-quadrant multiplication character-  
istics, with large signal multiplying bandwidths of 10 MHz.  
2.47 MSPS update rate  
Extended temperature range: −40°C to +12ꢀ°C  
4-quadrant multiplication  
Power-on reset  
0.ꢀ μA typical current consumption  
Guaranteed monotonic  
Daisy-chain mode  
The applied external reference input voltage (VREF) determines  
the full-scale output current. An integrated feedback resistor  
(RFB) provides temperature tracking and full-scale voltage  
output when combined with an external current-to-voltage  
precision amplifier.  
Readback function  
APPLICATIONS  
Portable battery-powered applications  
Waveform generators  
These DACs use a double-buffered, 3-wire serial interface that  
is compatible with SPI, QSPI™, MICROWIRE™, and most DSP  
interface standards. In addition, a serial data out (SDO) pin allows  
daisy-chaining when multiple packages are used. Data readback  
allows the user to read the contents of the DAC register via the  
SDO pin. On power-up, the internal shift register and latches  
are filled with 0s, and the DAC outputs are at zero scale.  
Analog processing  
Instrumentation applications  
Programmable amplifiers and attenuators  
Digitally controlled calibration  
Programmable filters and oscillators  
Composite video  
The AD5429/AD5439/AD5449 DACs are available in 16-lead  
TSSOP packages.  
Ultrasound  
Gain, offset, and voltage trimming  
FUNCTIONAL BLOCK DIAGRAM  
V
A
REF  
RFB  
R
AD5429/AD5439/AD5449  
V
DD  
R
A
FB  
SYNC  
I
I
1A  
OUT  
OUT  
SHIFT  
REGISTER  
INPUT  
REGISTER  
DAC  
REGISTER  
8-/10-/12-BIT  
R-2R DAC A  
SCLK  
SDIN  
2A  
SDO  
CLR  
LDAC  
I
I
1B  
2B  
OUT  
INPUT  
REGISTER  
DAC  
REGISTER  
8-/10-/12-BIT  
R-2R DAC B  
POWER-ON  
RESET  
OUT  
R
B
FB  
RFB  
R
LDAC  
V
B
REF  
Figure 1.  
1 U.S. Patent Number 5,689,257.  
Rev. C  
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 registeredtrademarks arethe 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 ©2004–2010 Analog Devices, Inc. All rights reserved.  
 
 
 
AD5429/AD5439/AD5449  
TABLE OF CONTENTS  
Features .............................................................................................. 1  
Digital-to-Analog Converter .................................................... 15  
Circuit Operation....................................................................... 15  
Single-Supply Applications ....................................................... 17  
Adding Gain................................................................................ 18  
Divider or Programmable Gain Element................................ 18  
Reference Selection .................................................................... 19  
Amplifier Selection .................................................................... 19  
Serial Interface............................................................................ 20  
Microprocessor Interfacing....................................................... 22  
PCB Layout and Power Supply Decoupling ........................... 24  
Evaluation Board for the DAC ................................................. 24  
Overview of AD54xx Devices....................................................... 28  
Outline Dimensions....................................................................... 29  
Ordering Guide .......................................................................... 29  
Applications....................................................................................... 1  
General Description......................................................................... 1  
Functional Block Diagram .............................................................. 1  
Revision History ............................................................................... 2  
Specifications..................................................................................... 3  
Timing Characteristics ................................................................ 5  
Timing Diagrams.......................................................................... 5  
Absolute Maximum Ratings............................................................ 7  
ESD Caution.................................................................................. 7  
Pin Configuration and Function Descriptions............................. 8  
Typical Performance Characteristics ............................................. 9  
Terminology .................................................................................... 14  
Theory of Operation ...................................................................... 15  
REVISION HISTORY  
Changes to Table 5.......................................................................... 15  
Changes to Table 6.......................................................................... 16  
Changes to Single-Supply Applications Section......................... 17  
Changes to Divider or Programmable Gain Element Section.... 18  
Changes to Table 7 Through Table 10 ......................................... 20  
Added ADSP-BF5xx-to-AD5429/AD5439/AD5449  
Interface Section........................................................................ 23  
Change to PCB Layout and  
Power Supply Decoupling Section .......................................... 25  
Changes to Power Supplies for the Evaluation Board Section.... 25  
Changes to Table 13 ....................................................................... 29  
Updated Outline Dimensions....................................................... 30  
Changes to Ordering Guide.......................................................... 30  
4/10—Rev. B to Rev. C  
Added to Figure 4 ............................................................................. 6  
3/08—Rev. A to Rev. B  
Added t13 and t14 Parameters to Table 2 ......................................... 5  
Changes to Figure 2.......................................................................... 5  
Changes to Figure 3.......................................................................... 6  
Changes to Figure 38...................................................................... 16  
Changes to Ordering Guide .......................................................... 30  
7/05—Rev. 0 to Rev. A  
Changes to Features List.................................................................. 1  
Changes to Specifications................................................................ 3  
Changes to Timing Characteristics................................................ 5  
Changes to Absolute Maximum Ratings Section......................... 7  
Changes to General Description Section .................................... 15  
7/04—Revision 0: Initial Version  
Rev. C | Page 2 of 32  
 
AD5429/AD5439/AD5449  
SPECIFICATIONS  
VDD = 2.5 V to 5.5 V, VREF = 10 V, IOUT2 = 0 V. Temperature range for Y version: −40°C to +125°C. All specifications TMIN to TMAX, unless  
otherwise noted. DC performance is measured with the OP177, and ac performance is measured with the AD8038, unless otherwise noted.  
Table 1.  
Parameter1  
Min  
Typ  
Max  
Unit  
Conditions  
STATIC PERFORMANCE  
AD5429  
Resolution  
8
±±.5  
±ꢀ  
Bits  
LSB  
LSB  
Relative Accuracy  
Differential Nonlinearity  
AD5439  
Guaranteed monotonic  
Guaranteed monotonic  
Resolution  
ꢀ±  
±±.5  
±ꢀ  
Bits  
LSB  
LSB  
Relative Accuracy  
Differential Nonlinearity  
AD5449  
Resolution  
ꢀ2  
±ꢀ  
Bits  
LSB  
Relative Accuracy  
Differential Nonlinearity  
Gain Error  
−ꢀ/+2 LSB  
±25  
Guaranteed monotonic  
mV  
Gain Error Temperature  
Coefficient  
±5  
ppm FSR/°C  
Output Leakage Current  
±5  
±ꢀ5  
nA  
nA  
Data = ±x±±±±, TA = 25°C, IOUTꢀ  
Data = ±x±±±±, IOUTꢀ  
REFERENCE INPUT  
Reference Input Range  
VREFA, VREFB Input Resistance  
VREFA-to-VREFB Input Resistance  
Mismatch  
±ꢀ±  
ꢀꢀ  
ꢀ.6  
V
kΩ  
%
9
ꢀ3  
2.5  
Input resistance temperature coefficient = −5± ppm/°C  
Typical = 25°C, maximum = ꢀ25°C  
Input Capacitance  
Code ±  
Code 4±95  
3.5  
3.5  
pF  
pF  
DIGITAL INPUTS/OUTPUT  
Input High Voltage, VIH  
ꢀ.7  
ꢀ.7  
V
V
VDD = 3.6 V to 5.5 V  
VDD = 2.5 V to 3.6 V  
Input Low Voltage, VIL  
Output High Voltage, VOH  
Output Low Voltage, VOL  
±.8  
±.7  
V
V
V
V
V
V
μA  
pF  
VDD = 2.7 V to 5.5 V  
VDD = 2.5 V to 2.7 V  
VDD = 4.5 V to 5.5 V, ISOURCE = 2±± μA  
VDD = 2.5 V to 3.6 V, ISOURCE = 2±± μA  
VDD = 4.5 V to 5.5 V, ISINK = 2±± μA  
VDD = 2.5 V to 3.6 V, ISINK = 2±± μA  
VDD − ꢀ  
VDD − ±.5  
±.4  
±.4  
Input Leakage Current, IIL  
Input Capacitance  
4
ꢀ±  
DYNAMIC PERFORMANCE  
Reference-Multiplying Bandwidth  
Output Voltage Settling Time  
ꢀ±  
MHz  
VREF = ±3.5 V p-p, DAC loaded all ꢀs  
RLOAD = ꢀ±± Ω, CLOAD = ꢀ5 pF, VREF = ꢀ± V,  
DAC latch alternately loaded with ±s and ꢀs  
Measured to ±ꢀ mV of FS  
Measured to ±4 mV of FS  
Measured to ±ꢀ6 mV of FS  
Digital Delay  
8±  
35  
3±  
2±  
3
ꢀ2±  
7±  
6±  
ns  
ns  
ns  
ns  
4±  
Digital-to-Analog Glitch Impulse  
nV-sec  
ꢀ LSB change around major carry, VREF = ± V  
Rev. C | Page 3 of 32  
 
AD5429/AD5439/AD5449  
Parameter1  
Min  
Typ  
Max  
Unit  
Conditions  
Multiplying Feedthrough Error  
DAC latches loaded with all ±s, VREF = ±3.5 V  
ꢀ MHz  
ꢀ± MHz  
DAC latches loaded with all ±s  
DAC latches loaded with all ꢀs  
Feedthrough to DAC output with CS high and  
alternate loading of all ±s and all ꢀs  
@ ꢀ kHz  
7±  
48  
ꢀ7  
3±  
5
dB  
dB  
pF  
pF  
Output Capacitance  
Digital Feedthrough  
ꢀ2  
25  
3
nV-sec  
Output Noise Spectral Density  
Analog THD  
Digital THD  
25  
8ꢀ  
nV/√Hz  
dB  
VREF = 3. 5 V p-p, all ꢀs loaded, f = ꢀ kHz  
Clock = ꢀ± MHz, VREF = 3.5 V  
ꢀ±± kHz fOUT  
5± kHz fOUT  
6ꢀ  
66  
dB  
dB  
SFDR Performance (Wide Band)  
Clock = ꢀ± MHz  
5±± kHz fOUT  
AD5449, 65k codes, VREF = 3.5 V  
55  
63  
65  
dB  
dB  
dB  
ꢀ±± kHz fOUT  
5± kHz fOUT  
Clock = 25 MHz  
5±± kHz fOUT  
ꢀ±± kHz fOUT  
5±  
6±  
62  
dB  
dB  
dB  
5± kHz fOUT  
SFDR Performance (Narrow Band)  
Clock = ꢀ± MHz  
5±± kHz fOUT  
AD5449, 65k codes, VREF = 3.5 V  
73  
8±  
87  
dB  
dB  
dB  
ꢀ±± kHz fOUT  
5± kHz fOUT  
Clock = 25 MHz  
5±± kHz fOUT  
ꢀ±± kHz fOUT  
7±  
75  
8±  
dB  
dB  
dB  
5± kHz fOUT  
Intermodulation Distortion  
f= 4± kHz, f2 = 5± kHz  
f= 4± kHz, f2 = 5± kHz  
POWER REQUIREMENTS  
Power Supply Range  
IDD  
AD5449, 65k codes, VREF = 3.5 V  
Clock = ꢀ± MHz  
Clock = 25 MHz  
72  
65  
dB  
dB  
2.5  
5.5  
±.7  
ꢀ±  
±.±±ꢀ  
V
μA  
μA  
%/%  
TA = 25°C, logic inputs = ± V or VDD  
TA = −4±°C to +ꢀ25°C, logic inputs = ± V or VDD  
∆VDD = ±5%  
±.5  
Power Supply Sensitivity  
Guaranteed by design and characterization, not subject to production test.  
Rev. C | Page 4 of 32  
AD5429/AD5439/AD5449  
TIMING CHARACTERISTICS  
All input signals are specified with tR = tF = 1 ns (10% to 90% of VDD) and timed from a voltage level of (VIL + VIH)/2. VDD = 2.5 V to 5.5 V,  
REF = 10 V, IOUT2 = 0 V, temperature range for Y version: −40°C to +125°C. All specifications TMIN to TMAX, unless otherwise noted.  
V
Table 2.  
Parameter1  
Limit at TMIN, TMAX  
Unit  
Conditions/Comments2  
fSCLK  
t1  
t2  
t3  
t4  
50  
20  
8
8
13  
5
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  
ns min  
ns min  
ns min  
MSPS  
Maximum clock frequency  
SCLK cycle time  
SCLK high time  
SCLK low time  
SYNC falling edge to SCLK falling edge setup time  
Data setup time  
Data hold time  
SYNC rising edge to SCLK falling edge  
Minimum SYNC high time  
t5  
t6  
t7  
4
5
t8  
30  
0
t9  
SCLK falling edge to LDAC falling edge  
LDAC pulse width  
t10  
t11  
12  
10  
25  
60  
12  
4.5  
2.47  
SCLK falling edge to LDAC rising edge  
SCLK active edge to SDO valid, strong SDO driver  
SCLK active edge to SDO valid, weak SDO driver  
CLR pulse width  
3
t12  
t13  
t14  
SYNC rising edge to LDAC falling edge  
Consists of cycle time, SYNC high time, data setup, and output voltage settling time  
Update Rate  
1 Guaranteed by design and characterization, not subject to production test.  
2 Falling or rising edge as determined by the control bits of the serial word. Strong or weak SDO driver selected via the control register.  
3 Daisy-chain and readback modes cannot operate at maximum clock frequency. SDO timing specifications are measured with a load circuit, as shown in Figure 5.  
TIMING DIAGRAMS  
t1  
SCLK  
t2  
t3  
t4  
t8  
t7  
SYNC  
SDIN  
t6  
t5  
DB0  
DB15  
t10  
t9  
1
LDAC  
t11  
2
LDAC  
1
ASYNCHRONOUS LDAC UPDATE MODE.  
SYNCHRONOUS LDAC UPDATE MODE.  
2
NOTES  
1. ALTERNATIVELY, DATA CAN BE CLOCKED INTO THE INPUT SHIFT REGISTER ON THE RISING EDGE OF SCLK AS  
DETERMINED BY THE CONTROL BITS. TIMING IS AS ABOVE, WITH SCLK INVERTED.  
Figure 2. Standalone Mode Timing Diagram  
Rev. C | Page 5 of 32  
 
 
 
AD5429/AD5439/AD5449  
t1  
SCLK  
t2  
t3  
t7  
t4  
SYNC  
t6  
t8  
t5  
DB0  
(N + 1)  
DB15  
(N)  
DB0  
(N)  
DB15  
(N + 1)  
SDIN  
t12  
DB0  
(N)  
DB15  
(N)  
SDO  
NOTES  
1. ALTERNATIVELY, DATA CAN BE CLOCKED INTO THE INPUT SHIFT REGISTER ON THE RISING EDGE OF SCLK AS  
DETERMINED BY THE CONTROL BITS. IN THIS CASE, DATA WOULD BE CLOCKED OUT OF SDO ON THE FALLING  
EDGE OF SCLK. TIMING IS AS ABOVE, WITH SCLK INVERTED.  
Figure 3. Daisy-Chain Timing Diagram  
SCLK  
16  
32  
SYNC  
SDIN  
DB15  
DB0  
DB15  
DB0  
INPUT WORD SPECIFIES  
REGISTER TO BE READ  
NOP CONDITION  
DB15  
DB0  
SDO  
SELECTED REGISTER DATA  
CLOCKED OUT  
UNDEFINED  
Figure 4. Readback Mode Timing Diagram  
200μA  
I
OL  
V
(MIN) + V (MAX)  
OL  
OH  
TO OUTPUT  
PIN  
2
C
L
50pF  
200μA  
I
OH  
Figure 5. Load Circuit for SDO Timing Specifications  
Rev. C | Page 6 of 32  
 
 
AD5429/AD5439/AD5449  
ABSOLUTE MAXIMUM RATINGS  
Transient currents of up to 100 mA do not cause SCR latch-up.  
TA = 25°C, unless otherwise noted.  
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. Only one absolute maximum rating may be  
applied at any one time.  
Table 3.  
Parameter  
Rating  
VDD to GND  
VREFx, RFBx to GND  
IOUT1, IOUT2 to GND  
Input Current to Any Pin Except Supplies  
Logic Inputs and Output1  
Operating Temperature Range  
Extended (Y Version)  
Storage Temperature Range  
Junction Temperature  
−0.3 V to +7 V  
−12 V to +12 V  
−0.3 V to +7 V  
10 mA  
−0.3 V to VDD + 0.3 V  
ESD CAUTION  
−40°C to +125°C  
−65°C to +150°C  
150°C  
16-Lead TSSOP, θJA Thermal Impedance  
Lead Temperature, Soldering (10 sec)  
IR Reflow, Peak Temperature (<20 sec)  
150°C/W  
300°C  
235°C  
1
SYNC  
Overvoltages at SCLK,  
, and SDIN are clamped by internal diodes.  
Rev. C | Page 7 of 32  
 
 
 
AD5429/AD5439/AD5449  
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS  
1
2
3
4
5
6
7
8
16  
15  
14  
13  
12  
11  
10  
9
I
1A  
2A  
I
1B  
2B  
OUT  
OUT  
I
I
OUT  
OUT  
R
A
A
R
B
FB  
FB  
AD5429/  
AD5439/  
V
V
B
REF  
REF  
DD  
AD5449  
GND  
LDAC  
SCLK  
SDIN  
V
TOP VIEW  
CLR  
(Not to Scale)  
SYNC  
SDO  
NC = NO CONNECT  
Figure 6. Pin Configuration  
Table 4. Pin Function Descriptions  
Pin No. Mnemonic Description  
DAC A Current Output.  
1
2
IOUT1A  
IOUT2A  
DAC A Analog Ground. This pin should typically be tied to the analog ground of the system, but it can be  
biased to achieve single-supply operation.  
3
RFBA  
DAC Feedback Resistor Pin. This pin establishes voltage output for the DAC by connecting to an external  
amplifier output.  
4
5
6
VREF  
GND  
LDAC  
A
DAC A Reference Voltage Input Pin.  
Ground Pin.  
Load DAC Input. This pin allows asynchronous or synchronous updates to the DAC output. The DAC is  
asynchronously updated when this signal goes low. Alternatively, if this line is held permanently low, an  
automatic or synchronous update mode is selected, whereby the DAC is updated on the 16th clock falling  
edge when the device is in standalone mode, or on the rising edge of SYNC when in daisy-chain mode.  
7
8
9
SCLK  
SDIN  
SDO  
Serial Clock Input. By default, data is clocked into the input shift register on the falling edge of the serial clock  
input. Alternatively, by means of the serial control bits, the device can be configured such that data is clocked  
into the shift register on the rising edge of SCLK.  
Serial Data Input. Data is clocked into the 16-bit input register on the active edge of the serial clock input. By  
default, data is clocked at power-on into the shift register on the falling edge of SCLK. The control bits allow  
the user to change the active edge to a rising edge.  
Serial Data Output. This pin allows a number of parts to be daisy-chained. By default, data is clocked into the  
shift register on the falling edge and clocked out via SDO on the rising edge of SCLK. Data is always clocked  
out on the alternate edge to loading data to the shift register. Writing the readback control word to the shift  
register makes the DAC register contents available for readback on the SDO pin, and they are clocked out on the  
next 16 opposite clock edges to the active clock edge.  
10  
11  
SYNC  
Active Low Control Input. This pin provides the frame synchronization signal for the input data. When SYNC  
goes low, it powers on the SCLK and DIN buffers, and the input shift register is enabled. Data is loaded into the  
shift register on the active edge of the subsequent clocks. In standalone mode, the serial interface counts the  
clocks, and data is latched into the shift register on the 16th active clock edge.  
Active Low Control Input. This pin clears the DAC output, input, and DAC registers. Configuration mode allows the  
user to enable the hardware CLR pin as a clear-to-zero scale or midscale, as required.  
CLR  
VDD  
12  
13  
14  
Positive Power Supply Input. These parts can be operated from a supply of 2.5 V to 5.5 V.  
DAC B Reference Voltage Input Pin.  
DAC B Feedback Resistor Pin. This pin establishes voltage output for the DAC by connecting to an external  
amplifier output.  
VREF  
B
RFBB  
15  
16  
IOUT2B  
IOUT1B  
DAC B Analog Ground. This pin typically should be tied to the analog ground of the system, but it can be  
biased to achieve single-supply operation.  
DAC B Current Output.  
Rev. C | Page 8 of 32  
 
AD5429/AD5439/AD5449  
TYPICAL PERFORMANCE CHARACTERISTICS  
0.20  
0.20  
0.15  
0.10  
0.05  
0
T
= 25°C  
T = 25°C  
A
A
V
V
= 10V  
= 5V  
V
V
= 10V  
REF  
REF  
= 5V  
DD  
0.15  
0.10  
0.05  
0
DD  
–0.05  
–0.10  
–0.15  
–0.20  
–0.05  
–0.10  
–0.15  
–0.20  
0
50  
100  
150  
200  
250  
0
50  
100  
150  
200  
250  
CODE  
CODE  
Figure 7. INL vs. Code (8-Bit DAC)  
Figure 10. DNL vs. Code (8-Bit DAC)  
0.5  
0.4  
0.5  
0.4  
T
V
V
= 25°C  
T
V
V
= 25°C  
A
A
= 10V  
= 10V  
REF  
= 5V  
REF  
= 5V  
DD  
DD  
0.3  
0.3  
0.2  
0.2  
0.1  
0.1  
0
0
–0.1  
–0.2  
–0.3  
–0.4  
–0.1  
–0.2  
–0.3  
–0.4  
–0.5  
0
–0.5  
0
200  
400  
600  
800  
1000  
200  
400  
600  
800  
1000  
CODE  
CODE  
Figure 8. INL vs. Code (10-Bit DAC)  
Figure 11. DNL vs. Code (10-Bit DAC)  
1.0  
0.8  
1.0  
0.8  
T
V
V
= 25°C  
T = 25°C  
A
A
= 10V  
V
= 10V  
REF  
= 5V  
REF  
= 5V  
DD  
V
DD  
0.6  
0.6  
0.4  
0.4  
0.2  
0.2  
0
0
–0.2  
–0.4  
–0.6  
–0.8  
–0.2  
–0.4  
–0.6  
–0.8  
–1.0  
0
–1.0  
0
500  
1000  
1500  
2000  
2500  
3000  
3500  
4000  
500  
1000  
1500  
2000  
2500  
3000  
3500  
4000  
CODE  
CODE  
Figure 9. INL vs. Code (12-Bit DAC)  
Figure 12. DNL vs. Code (12-Bit DAC)  
Rev. C | Page 9 of 32  
 
AD5429/AD5439/AD5449  
8
7
6
5
4
3
2
1
0
0.6  
0.5  
0.4  
T
= 25°C  
A
MAX INL  
0.3  
V
= 5V  
DD  
0.2  
0.1  
0
T
V
= 25°C  
= 5V  
A
DD  
MIN INL  
–0.1  
V
= 3V  
DD  
–0.2  
–0.3  
V
= 2.5V  
DD  
1.5  
2.0  
2.5  
3.0  
3.5  
4.0  
4.5  
5.0  
0
0.5  
1.0  
2
3
4
5
6
7
8
9
10  
INPUT VOLTAGE (V)  
REFERENCE VOLTAGE  
Figure 13. INL vs. Reference Voltage  
Figure 16. Supply Current vs. Logic Input Voltage  
1.6  
–0.40  
T
= 25°C  
A
V
= 5V  
DD  
1.4  
1.2  
1.0  
0.8  
0.6  
0.4  
0.2  
0
–0.45  
–0.50  
–0.55  
–0.60  
–0.65  
–0.70  
I
1 V = 5V  
OUT DD  
I
1 V = 3V  
DD  
OUT  
MIN DNL  
–40  
–20  
0
20  
40  
60  
80  
100  
120  
2
3
4
5
6
7
8
9
10  
TEMPERATURE (°C)  
REFERENCE VOLTAGE  
Figure 14. DNL vs. Reference Voltage  
Figure 17. IOUT1 Leakage Current vs. Temperature  
0.50  
5
4
3
2
1
0
0.45  
0.40  
0.35  
0.30  
0.25  
0.20  
0.15  
0.10  
0.05  
0
V
= 5V  
V
= 5V  
DD  
DD  
ALL 0s  
ALL 1s  
V
DD  
= 2.5V  
V
= 2.5V  
DD  
–1  
–2  
–3  
–4  
–5  
ALL 1s  
ALL 0s  
V
= 10V  
REF  
–60 –40 –20  
0
20  
40  
60  
80  
100 120 140  
–60 –40 –20  
0
20  
40  
60  
80  
100 120 140  
TEMPERATURE (°C)  
TEMPERATURE (°C)  
Figure 18. Supply Current vs. Temperature  
Figure 15. Gain Error vs. Temperature  
Rev. C | Page 10 of 32  
AD5429/AD5439/AD5449  
3
0
14  
12  
10  
8
T
V
= 25°C  
A
T
= 25°C  
A
= 5V  
DD  
LOADING ZS TO FS  
V
= 5V  
DD  
–3  
–6  
–9  
6
V
V
= 3V  
DD  
DD  
4
V
V
V
V
V
= ±2V, AD8038 C 1.47pF  
REF  
REF  
REF  
REF  
REF  
C
= 2.5V  
= ±2V, AD8038 C 1pF  
C
= ±0.15V, AD8038 C 1pF  
C
2
= ±0.15V, AD8038 C 1.47pF  
C
= ±3.51V, AD8038 C 1.8pF  
C
0
10k  
100k  
1M  
10M  
100M  
1
10  
100  
1k  
10k  
100k  
1M  
10M  
100M  
FREQUENCY (Hz)  
FREQUENCY (Hz)  
Figure 19. Supply Current vs. Update Rate  
Figure 22. Reference Multiplying Bandwidth vs. Frequency  
and Compensation Capacitor  
6
0
0.045  
0.040  
0.035  
0.030  
0.025  
0.020  
0.015  
0.010  
0.005  
0
T
= 25°C  
ALL ON  
DB11  
DB10  
DB9  
DB8  
DB7  
A
T
V
= 25°C  
= 0V  
0x7FF TO 0x800  
A
LOADING  
ZS TO FS  
REF  
–6  
–12  
–18  
–24  
–30  
–36  
–42  
–48  
–54  
–60  
–66  
–72  
–78  
–84  
–90  
–96  
–102  
AMP = AD8038  
= 1.8pF  
V
= 5V  
DD  
C
COMP  
DB6  
V
= 3V  
DD  
DB5  
DB4  
DB3  
DB2  
DB1  
DB0  
0x800 TO 0x7FF  
= 3V  
V
DD  
T
V
= 25°C  
A
= 5V  
DD  
V
= ±3.5V  
= 1.8pF  
REF  
ALL OFF  
C
–0.005  
–0.010  
COMP  
AMP = AD8038  
V
= 5V  
DD  
1
10  
100  
1k  
10k  
100k  
1M 10M 100M  
0
20  
40  
60  
80  
100 120 140 160 180 200  
TIME (ns)  
FREQUENCY (Hz)  
Figure 20. Reference Multiplying Bandwidth vs. Frequency and Code  
Figure 23. Midscale Transition, VREF = 0 V  
0.2  
0
–1.68  
–1.69  
–1.70  
–1.71  
–1.72  
–1.73  
–1.74  
–1.75  
–1.76  
–1.77  
T
V
= 25°C  
= 3.5V  
A
0x7FF TO 0x800  
REF  
AMP = AD8038  
= 1.8pF  
V
= 5V  
DD  
C
COMP  
–0.2  
–0.4  
V
= 3V  
DD  
V
= 5V  
V
DD  
= 3V  
DD  
T
V
V
= 25°C  
A
–0.6  
–0.8  
= 5V  
DD  
=
±
3.5V  
REF  
C
= 1.8pF  
COMP  
0x800 TO 0x7FF  
20 40 60  
AMP = AD8038  
1
10 100  
1k  
10k  
100k  
1M  
10M  
100M  
0
80  
100 120 140 160 180 200  
TIME (ns)  
FREQUENCY (Hz)  
Figure 21. Reference Multiplying Bandwidth—All 1s Loaded  
Figure 24. Midscale Transition, VREF = 3.5 V  
Rev. C | Page 11 of 32  
AD5429/AD5439/AD5449  
90  
80  
70  
60  
50  
40  
30  
20  
10  
0
20  
T
V
= 25°C  
A
= 3V  
DD  
AMP = AD8038  
0
–20  
MCLK = 5MHz  
MCLK = 10MHz  
–40  
FULL SCALE  
ZERO SCALE  
MCLK = 25MHz  
–60  
–80  
–100  
–120  
T
V
= 25°C  
= 3.5V  
A
REF  
AMP = AD8038  
1
100  
1k  
10k  
100k  
1M  
10M  
10  
0
100 200 300 400 500 600 700 800 900 1000  
fOUT (kHz)  
FREQUENCY (Hz)  
Figure 25. Power Supply Rejection Ratio vs. Frequency  
Figure 28. Wideband SFDR vs. fOUT Frequency  
–60  
–65  
–70  
–75  
–80  
–85  
0
T
V
= 25°C  
A
T
V
V
= 25°C  
A
= 5V  
DD  
= 3V  
DD  
–10  
–20  
–30  
–40  
–50  
–60  
–70  
–80  
–90  
AMP = AD8038  
65k CODES  
= 3.5V p-p  
REF  
–90  
1
0
2
4
6
8
10  
12  
10  
100  
1k  
10k  
100k  
1M  
FREQUENCY (MHz)  
FREQUENCY (Hz)  
Figure 26. THD + Noise vs. Frequency  
Figure 29. Wideband SFDR, fOUT = 100 kHz, Clock = 25 MHz  
100  
80  
60  
40  
20  
0
–10  
–20  
–30  
–40  
–50  
–60  
–70  
–80  
–90  
–100  
T
V
= 25°C  
A
= 5V  
DD  
MCLK = 1MHz  
AMP = AD8038  
65k CODES  
MCLK = 200kHz  
MCLK = 0.5MHz  
T
V
= 25°C  
= 3.5V  
A
REF  
AMP = AD8038  
0
0
0
0.5  
1.0  
1.5  
2.0  
2.5  
3.0  
3.5  
4.0  
4.5  
5.0  
20  
40  
60  
80  
100 120 140 160 180 200  
FREQUENCY (MHz)  
fOUT (kHz)  
Figure 27. Wideband SFDR vs. fOUT Frequency  
Figure 30. Wideband SFDR, fOUT = 500 kHz, Clock = 10 MHz  
Rev. C | Page 12 of 32  
AD5429/AD5439/AD5449  
0
–10  
–20  
–30  
–40  
–50  
–60  
–70  
–80  
–90  
–100  
0
–10  
–20  
–30  
–40  
–50  
–60  
–70  
–80  
–90  
T
V
= 25°C  
T = 25°C  
A
DD  
AMP = AD8038  
65k CODES  
A
= 5V  
V
= 3V  
DD  
AMP = AD8038  
65k CODES  
0
0.5  
1.0  
1.5  
2.0  
2.5  
3.0  
3.5  
4.0  
4.5  
5.0  
70  
75  
80  
85  
90  
95  
100 105 110 115 120  
FREQUENCY (MHz)  
FREQUENCY (kHz)  
Figure 31. Wideband SFDR, fOUT = 50 kHz, Clock = 10 MHz  
Figure 34. Narrow-Band IMD, fOUT = 90 kHz, 100 kHz, Clock = 10 MHz  
0
–10  
–20  
–30  
–40  
–50  
–60  
–70  
–80  
–90  
–100  
0
T
V
= 25°C  
DD  
A
T
V
= 25°C  
DD  
A
= 3V  
= 5V  
–10  
–20  
–30  
–40  
–50  
–60  
–70  
–80  
–90  
–100  
AMP = AD8038  
65k CODES  
AMP = AD8038  
65k CODES  
250 300 350 400 450 500 550 600 650 700 750  
0
50  
100  
150  
200  
250  
300  
350  
400  
FREQUENCY (kHz)  
FREQUENCY (kHz)  
Figure 32. Narrow-Band Spectral Response, fOUT = 500 kHz, Clock = 25 MHz  
Figure 35. Wideband IMD, fOUT = 90 kHz, 100 kHz, Clock = 25 MHz  
20  
300  
T
V
= 25°C  
DD  
T
= 25°C  
A
A
= 3V  
ZERO SCALE LOADED TO DAC  
MIDSCALE LOADED TO DAC  
FULL SCALE LOADED TO DAC  
AMP = AD8038  
AMP = AD8038  
65k CODES  
0
–20  
250  
200  
150  
100  
50  
–40  
–60  
–80  
–100  
–120  
0
50  
60  
70  
80  
90  
100 110 120 130 140 150  
100  
1k  
10k  
FREQUENCY (Hz)  
100k  
FREQUENCY (kHz)  
Figure 33. Narrow-Band SFDR, fOUT = 100 kHz, Clock = 25 MHz  
Figure 36. Output Noise Spectral Density  
Rev. C | Page 13 of 32  
AD5429/AD5439/AD5449  
TERMINOLOGY  
Relative Accuracy (Endpoint Nonlinearity)  
Digital Crosstalk  
A measure of the maximum deviation from a straight line  
passing through the endpoints of the DAC transfer function.  
It is measured after adjusting for zero and full scale and is typically  
expressed in LSBs or as a percentage of the full-scale reading.  
The glitch impulse transferred to the outputs of one DAC in  
response to a full-scale code change (all 0s to all 1s, or vice versa)  
in the input register of the other DAC. It is expressed in nV-sec.  
Analog Crosstalk  
Differential Nonlinearity  
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  
The difference in the measured change and the ideal 1 LSB  
change between two adjacent codes. A specified differential  
nonlinearity of −1 LSB maximum over the operating temperature  
range ensures monotonicity.  
LDAC  
(all 0s to all 1s, or vice versa) while keeping  
high and  
LDAC  
then pulsing  
low and monitoring the output of the DAC  
whose digital code has not changed. The area of the glitch is  
expressed in nV-sec.  
Gain Error (Full-Scale Error)  
A measure of the output error between an ideal DAC and the  
actual device output. For these DACs, ideal maximum output is  
Channel-to-Channel Isolation  
The portion of input signal from the reference input of a DAC  
that appears at the output of another DAC. It is expressed in dB.  
V
REF − 1 LSB. The gain error of the DACs is adjustable to zero  
with an external resistance.  
Output Leakage Current  
Total Harmonic Distortion (THD)  
The current that flows into the DAC ladder switches when they  
are turned off. For the IOUT1x terminal, it can be measured by  
loading all 0s to the DAC and measuring the IOUT1 current.  
Minimum current flows into the IOUT2x line when the DAC is  
loaded with all 1s.  
The DAC is driven by an ac reference. The ratio of the rms sum  
of the harmonics of the DAC output to the fundamental value is  
the THD. Usually only the lower-order harmonics are included,  
such as the second to fifth harmonics.  
2
2
2
2
V2 +V3 +V4 +V5  
Output Capacitance  
Capacitance from IOUT1 or IOUT2 to AGND.  
THD = 20 log  
V1  
Intermodulation Distortion (IMD)  
Output Current Settling Time  
The DAC is driven by two combined sine wave references of  
Frequency fa and Frequency fb. Distortion products are produced  
at sum and difference frequencies of mfa nfb, where m, n = 0, 1,  
2, 3 … Intermodulation terms are those for which m or n is not  
equal to 0. The second-order terms include (fa + fb) and (fa − fb),  
and the third-order terms are (2fa + fb), (2fa − fb), (f + 2fa + 2fb),  
and (fa − 2fb). IMD is defined as  
The amount of time for the output to settle to a specified level  
for a full-scale input change. For these devices, it is specified  
with a 100 Ω resistor to ground.  
Digital-to-Analog Glitch Impulse  
The amount of charge injected from the digital inputs to the  
analog output when the inputs change state. This is normally  
specified as the area of the glitch in either pA-sec or nV-sec,  
depending on whether the glitch is measured as a current or  
voltage signal.  
RMS Sum of the Sum and Diff Distortion Products  
IMD = 20log  
RMS Amplitude of the Fundamental  
Digital Feedthrough  
Compliance Voltage Range  
When the device is not selected, high frequency logic activity  
on the digital inputs of the device is capacitively coupled through  
the device and produces noise on the IOUT pins and, subsequently,  
on the circuitry that follows. This noise is digital feedthrough.  
The maximum range of (output) terminal voltage for which the  
device provides the specified characteristics.  
Multiplying Feedthrough Error  
The error due to capacitive feedthrough from the DAC  
reference input to the DAC IOUT1x terminal when all 0s are  
loaded to the DAC.  
Rev. C | Page 14 of 32  
 
AD5429/AD5439/AD5449  
THEORY OF OPERATION  
DIGITAL-TO-ANALOG CONVERTER  
When an output amplifier is connected in unipolar mode, the  
output voltage is given by  
The AD5429/AD5439/AD5449 are 8-, 10-, and 12-bit, dual-  
channel, current output DACs consisting of a standard inverting  
R-2R ladder configuration. Figure 37 shows a simplified diagram  
for a single channel of the AD5449. The feedback resistor, RFBA,  
has a value of R. The value of R is typically 10 kΩ (with a  
minimum of 8 kΩ and a maximum of 12 kΩ). If IOUT1A and  
IOUT2A are kept at the same potential, a constant current flows  
into each ladder leg, regardless of digital input code. Therefore,  
the input resistance presented at VREFA is always constant.  
VOUT = VREF × D/2n  
where:  
D is the fractional representation of the digital word loaded to  
the DAC.  
D = 0 to 255 (AD5429)  
= 0 to 1023 (AD5439)  
= 0 to 4095 (AD5449)  
n is the number of bits.  
R
R
R
V
A
REF  
With a fixed 10 V reference, the circuit shown in Figure 38 gives  
a unipolar 0 V to −10 V output voltage swing. When VIN is an ac  
signal, the circuit performs 2-quadrant multiplication.  
2R  
S1  
2R  
S2  
2R  
S3  
2R  
2R  
R
S12  
R
A
FB  
I
I
1A  
2A  
OUT  
OUT  
Table 5 shows the relationship between digital code and the  
expected output voltage for unipolar operation using the 8-bit  
AD5429 DAC.  
DAC DATA LATCHES  
AND DRIVERS  
Table 5. Unipolar Code Table  
Figure 37. Simplified Ladder  
Digital Input  
1111 1111  
1000 0000  
0000 0001  
0000 0000  
Analog Output (V)  
Access is provided to the VREFx, RFBx, IOUT1x, and IOUT2x termi-  
nals of the DACs, making the devices extremely versatile and  
allowing them to be configured in several operating modes, such  
as unipolar mode, bipolar output mode, or single-supply mode.  
−VREF (255/256)  
−VREF (128/256) = −VREF/2  
−VREF (1/256)  
−VREF (0/256) = 0  
CIRCUIT OPERATION  
Unipolar Mode  
Using a single op amp, these devices can easily be configured to  
provide 2-quadrant multiplying operation or a unipolar output  
voltage swing, as shown in Figure 38.  
V
DD  
R2  
C1  
A1  
V
R
A
DD  
FB  
I
1A  
AD5429/  
AD5439/  
AD5449  
OUT  
V
V
x
REF  
REF  
I
2A  
R1  
OUT  
V
= 0V TO –V  
REF  
OUT  
SYNC SCLK SDIN GND  
MICROCONTROLLER  
AGND  
NOTES  
1. R1 AND R2 USED ONLY IF GAIN ADJUSTMENT IS REQUIRED.  
2. C1 PHASE COMPENSATION (1pF TO 2pF) MAY BE REQUIRED  
IF A1 IS A HIGH SPEED AMPLIFIER.  
3. DAC B OMITTED FOR CLARITY.  
Figure 38. Unipolar Operation  
Rev. C | Page 15 of 32  
 
 
 
 
 
 
AD5429/AD5439/AD5449  
Bipolar Operation  
Stability  
In some applications, it may be necessary to generate full  
4-quadrant multiplying operation or a bipolar output swing.  
This can easily be accomplished by using another external  
amplifier and three external resistors, as shown in Figure 39.  
In the I-to-V configuration, the IOUT of the DAC and the inverting  
node of the op amp must be connected as closely as possible, and  
proper PCB layout techniques must be used. Because every code  
change corresponds to a step function, gain peaking may occur  
if the op amp has limited gain bandwidth product (GBP) and  
there is excessive parasitic capacitance at the inverting node.  
This parasitic capacitance introduces a pole into the open-loop  
response, which can cause ringing or instability in the closed-  
loop applications circuit.  
When VIN is an ac signal, the circuit performs 4-quadrant  
multiplication. When connected in bipolar mode, the output  
voltage is  
VOUT  
=
(
V
REF ×D/2n 1  
VREF  
)
As shown in Figure 38 and Figure 39, an optional compensation  
capacitor, C1, can be added in parallel with RFBx for stability.  
Too small a value of C1 can produce ringing at the output,  
whereas too large a value can adversely affect the settling time.  
C1 should be found empirically, but 1 pF to 2 pF is generally  
adequate for the compensation.  
where:  
D is the fractional representation of the digital word loaded to  
the DAC.  
D = 0 to 255 (AD5429)  
= 0 to 1023 (AD5439)  
= 0 to 4095 (AD5449)  
n is the number of bits.  
Table 6 shows the relationship between digital code and the  
expected output voltage for bipolar operation with the AD5429.  
Table 6. Bipolar Code  
Digital Input  
1111 1111  
1000 0000  
0000 0001  
0000 0000  
Analog Output (V)  
+VREF (255/256)  
0
−VREF (255/256)  
−VREF (256/256)  
R3  
20k  
V
V
DD  
R2  
R5  
20kΩ  
C1  
R
A
DD  
FB  
R4  
10kΩ  
R1  
I
1A  
AD5429/  
AD5439/  
AD5449  
OUT  
V
x
V
±10V  
A1  
REF  
REF  
A2  
I
2A  
R1  
OUT  
V
= –V  
REF  
TO +V  
REF  
SYNC SCLK SDIN  
GND  
OUT  
AGND  
MICROCONTROLLER  
NOTES  
1. R1 AND R2 USED ONLY IF GAIN ADJUSTMENT IS REQUIRED.  
ADJUST R1 FOR V = 0V WITH CODE 10000000 LOADED TO DAC.  
OUT  
2. MATCHING AND TRACKING IS ESSENTIAL FOR RESISTOR PAIRS  
R3 AND R4.  
3. C1 PHASE COMPENSATION (1pF TO 2pF) MAY BE REQUIRED  
IF A1/A2 IS A HIGH SPEED AMPLIFIER.  
4. DAC B AND ADDITIONAL PINS OMITTED FOR CLARITY.  
Figure 39. Bipolar Operation  
Rev. C | Page 16 of 32  
 
 
AD5429/AD5439/AD5449  
Note that VIN is limited to low voltages because the switches  
in the DAC ladder no longer have the same source-drain drive  
voltage. As a result, their on resistance differs and degrades the  
integral linearity of the DAC. Also, VIN must not go negative by  
more than 0.3 V, or an internal diode turns on, causing the device  
to exceed the maximum ratings. In this type of application, the  
full range of multiplying capability of the DAC is lost.  
SINGLE-SUPPLY APPLICATIONS  
Voltage-Switching Mode  
Figure 40 shows the DACs operating in voltage-switching mode.  
The reference voltage, VIN, is applied to the IOUT1A pin; IOUT2A  
is connected to AGND; and the output voltage is available at the  
VREFA terminal. In this configuration, a positive reference voltage  
results in a positive output voltage, making single-supply operation  
possible. The output from the DAC is voltage at a constant  
impedance (the DAC ladder resistance). Therefore, an op amp  
is necessary to buffer the output voltage. The reference input  
no longer sees a constant input impedance; instead, it sees one  
that varies with code. Therefore, the voltage input should be  
driven from a low impedance source.  
Positive Output Voltage  
The output voltage polarity is opposite to the VREF polarity for  
dc reference voltages. To achieve a positive voltage output, an  
applied negative reference to the input of the DAC is preferred  
over the output inversion through an inverting amplifier because  
of the resistor tolerance errors. To generate a negative reference,  
the reference can be level-shifted by an op amp such that the VOUT  
and GND pins of the reference become the virtual ground and  
−2.5 V, respectively, as shown in Figure 41.  
V
V
DD  
R1  
R2  
R
A
FB  
DD  
V
I
1A  
IN  
OUT  
V
8-/10-/12-BIT  
DAC  
OUT  
V
A
REF  
I
2A  
OUT  
GND  
NOTES  
1. ADDITIONAL PINS OMITTED FOR CLARITY.  
2. C1 PHASE COMPENSATION (1pF TO 2pF) MAY BE REQUIRED  
IF A1 IS A HIGH SPEED AMPLIFIER.  
Figure 40. Single-Supply Voltage-Switching Mode  
V
= +5V  
DD  
ADR03  
V
V
IN  
OUT  
GND  
+5V  
C1  
R
A
V
FB  
DD  
–2.5V  
I
I
1A  
2A  
OUT  
V
A
8-/10-/12-BIT  
DAC  
REF  
OUT  
V
= 0V TO +2.5V  
OUT  
GND  
–5V  
NOTES  
1. ADDITIONAL PINS OMITTED FOR CLARITY.  
2. C1 PHASE COMPENSATION (1pF TO 2pF) MAY BE REQUIRED  
IF A1 IS A HIGH SPEED AMPLIFIER.  
Figure 41. Positive Voltage Output with Minimum Components  
Rev. C | Page 17 of 32  
 
 
 
AD5429/AD5439/AD5449  
As D is reduced, the output voltage increases. For small values of  
the Digital Fraction D, it is important to ensure that the amplifier  
does not saturate and the required accuracy is met. For example,  
an 8-bit DAC driven with binary code of 0x10 (0001 0000)—that  
is, 16 decimal—in the circuit of Figure 43 should cause the output  
voltage to be 16 × VIN. However, if the DAC has a linearity speci-  
fication of 0.5 LSB, D can have a weight in the range of 15.5/256  
to 16.5/256, so that the possible output voltage is in the range of  
15.5 VIN to 16.5 VIN. This range represents an error of 3%, even  
though the DAC itself has a maximum error of 0.2%.  
ADDING GAIN  
In applications in which the output voltage must be greater than  
VIN, gain can be added with an additional external amplifier, or  
it can be achieved in a single stage. Consider the effect of temper-  
ature coefficients of the thin film resistors of the DAC. Simply  
placing a resistor in series with the RFB resistor causes mismatches  
in the temperature coefficients, resulting in larger gain temper-  
ature coefficient errors. Instead, the circuit in Figure 42 shows  
the recommended method of increasing the gain of the circuit.  
R1, R2, and R3 should have similar temperature coefficients,  
but they need not match the temperature coefficients of the  
DAC. This approach is recommended in circuits in which  
gains of greater than 1 are required.  
DAC leakage current is also a potential error source in divider  
circuits. The leakage current must be counterbalanced by an  
opposite current supplied from the op amp through the DAC.  
Because only a fraction, D, of the current into the VREFx terminal  
is routed to the IOUT1 terminal, the output voltage changes as  
follows:  
DIVIDER OR PROGRAMMABLE GAIN ELEMENT  
Current-steering DACs are very flexible and lend themselves  
to many applications. If this type of DAC is connected as the  
feedback element of an op amp and RFBA is used as the input  
resistor, as shown in Figure 43, the output voltage is inversely  
proportional to the digital input fraction, D.  
Output Error Voltage Due to DAC Leakage = (Leakage × R)/D  
where R is the DAC resistance at the VREFx terminal.  
For a DAC leakage current of 10 nA, R = 10 kΩ, and a gain (that  
is, 1/D) of 16, the error voltage is 1.6 mV.  
For D = 1 − 2−n, the output voltage is  
n  
(
)
VOUT = −VIN /D = −VIN / 12  
V
DD  
C1  
V
R
A
DD  
FB  
I
1A  
2A  
OUT  
R1  
8-/10-/12-BIT  
DAC  
V
V
V
A
IN  
OUT  
REF  
I
OUT  
R3  
GND  
R2 + R3  
R2  
GAIN =  
R2  
R2R3  
R2 + R3  
R1 =  
NOTES  
1. ADDITIONAL PINS OMITTED FOR CLARITY.  
2. C1 PHASE COMPENSATION (1pF TO 2pF) MAY BE REQUIRED  
IF A1 IS A HIGH SPEED AMPLIFIER.  
Figure 42. Increasing Gain of Current Output DAC  
V
DD  
V
IN  
R
A
V
FB  
DD  
I
1A  
OUT  
8-/10-/12-BIT  
DAC  
V
A
REF  
I
2A  
OUT  
GND  
V
OUT  
NOTES  
1. ADDITIONAL PINS OMITTED FOR CLARITY.  
Figure 43. Current-Steering DAC Used as a Divider or Programmable Gain Element  
Rev. C | Page 18 of 32  
 
 
 
 
AD5429/AD5439/AD5449  
voltage change is superimposed on the desired change in output  
between the two codes and gives rise to a differential linearity  
error, which, if large enough, could cause the DAC to be non-  
monotonic. The input bias current of an op amp also generates  
an offset at the voltage output as a result of the bias current flowing  
in the feedback resistor, RFB. Most op amps have input bias  
currents low enough to prevent significant errors in 12-bit  
applications.  
REFERENCE SELECTION  
When selecting a reference for use with the AD54xx series of  
current output DACs, pay attention to the reference output voltage  
temperature coefficient specification. This parameter affects not  
only the full-scale error, but it can also affect the linearity (INL and  
DNL) performance. The reference temperature coefficient should  
be consistent with the system accuracy specifications. For example,  
an 8-bit system required to hold its overall specification to within  
1 LSB over the temperature range of 0°C to 50°C dictates that the  
maximum system drift with temperature should be less than  
78 ppm/°C. A 12-bit system with the same temperature range  
to overall specification within 2 LSBs requires a maximum drift  
of 10 ppm/°C. By choosing a precision reference with a low output  
temperature coefficient, this error source can be minimized.  
Table 7 lists some references available from Analog Devices, Inc.,  
that are suitable for use with this range of current output DACs.  
Common-mode rejection of the op amp is important in voltage-  
switching circuits because it produces a code-dependent error  
at the voltage output of the circuit. Most op amps have adequate  
common-mode rejection for use at 8-, 10-, and 12-bit resolution.  
If the DAC switches are driven from true wideband low impedance  
sources (VIN and AGND), they settle quickly. Consequently, the  
slew rate and settling time of a voltage-switching DAC circuit  
is determined largely by the output op amp. To obtain minimum  
settling time in this configuration, minimize capacitance at the  
AMPLIFIER SELECTION  
VREF node (the voltage output node in this application) of the  
The primary requirement for the current-steering mode is an  
amplifier with low input bias currents and low input offset voltage.  
Because of the code-dependent output resistance of the DAC,  
the input offset voltage of an op amp is multiplied by the variable  
gain of the circuit. A change in this noise gain between two  
adjacent digital fractions produces a step change in the output  
voltage due to the amplifier input offset voltage. This output  
DAC by using low input capacitance buffer amplifiers and careful  
board design.  
Most single-supply circuits include ground as part of the analog  
signal range, which, in turn, requires an amplifier that can handle  
rail-to-rail signals. Analog Devices offers a wide range of single-  
supply amplifiers (see Table 8 and Table 9).  
Table 7. Suitable Analog Devices Precision References  
Part No. OutputVoltage (V) Initial Tolerance (%)  
Temp Drift (ppm/°C)  
ISS (mA)  
Output Noise (μV p-p) Package  
ADR01  
ADR01  
ADR02  
ADR02  
ADR03  
ADR03  
ADR06  
ADR06  
ADR431  
ADR435  
ADR391  
ADR395  
10  
10  
5
0.05  
0.05  
0.06  
0.06  
0.10  
0.10  
0.10  
0.10  
0.04  
0.04  
0.16  
0.10  
3
9
3
9
3
9
3
9
3
3
9
9
1
1
1
1
1
1
1
1
0.8  
0.8  
0.12  
0.12  
20  
20  
10  
10  
6
SOIC-8  
TSOT-23, SC70  
SOIC-8  
TSOT-23, SC70  
SOIC-8  
TSOT-23, SC70  
SOIC-8  
TSOT-23, SC70  
SOIC-8  
SOIC-8  
TSOT-23  
TSOT-23  
5
2.5  
2.5  
3
3
2.5  
5
6
10  
10  
3.5  
8
5
8
2.5  
5
Table 8. Suitable Analog Devices Precision Op Amps  
Part No. Supply Voltage (V)  
VOS (Max) (μV)  
IB (Max) (nA) 0.1 Hz to 10 Hz Noise (μV p-p) Supply Current (μA) Package  
OP97  
2 to 20  
2.5 to 15  
2.7 to 5  
1.8 to 6  
2.7 to 6  
25  
60  
5
50  
5
0.1  
2
0.05  
0.001  
0.1  
0.5  
0.4  
1
2.3  
0.5  
600  
500  
975  
50  
SOIC-8  
OP1177  
AD8551  
AD8603  
AD8628  
MSOP, SOIC-8  
MSOP, SOIC-8  
TSOT  
850  
TSOT, SOIC-8  
Table 9. Suitable Analog Devices High Speed Op Amps  
Part No.  
AD8065  
AD8021  
AD8038  
AD9631  
Supply Voltage (V) BW ꢁ ACL (MHz) Slew Rate (V/μs)  
VOS (Max) (μV) IB (Max) (nA)  
Package  
5 to 24  
145  
490  
350  
320  
180  
120  
425  
1300  
1500  
1000  
3000  
10,000  
6000  
10,500  
750  
SOIC-8, SOT-23, MSOP  
SOIC-8, MSOP  
SOIC-8, SC70-5  
SOIC-8  
2.5 to 12  
3 to 12  
3 to 6  
7000  
Rev. C | Page 19 of 32  
 
 
 
 
 
AD5429/AD5439/AD5449  
SDO Control (SDO1 and SDO2)  
SERIAL INTERFACE  
The SDO bits enable the user to control the SDO output driver  
strength, disable the SDO output, or configure it as an open-drain  
driver. The strength of the SDO driver affects the timing of t12,  
and, when stronger, allows a faster clock cycle.  
The AD5429/AD5439/AD5449 have an easy-to-use, 3-wire  
interface that is compatible with SPI, QSPI, MICROWIRE, and  
most DSP interface standards. Data is written to the device in  
16-bit words. Each 16-bit word consists of four control bits and  
eight, 10, or 12 data bits, as shown in Figure 44 through Figure 46.  
Table 10. SDO Control Bits  
Low Power Serial Interface  
SDO2  
SDO1  
Function Implemented  
0
0
Full SDO driver  
To minimize the power consumption of the device, the interface  
powers up fully only when the device is being written to, that is,  
0
1
1
1
0
1
Weak SDO driver  
SDO configured as open drain  
Disable SDO output  
SYNC  
on the falling edge of  
. The SCLK and SDIN input buffers  
SYNC  
are powered down on the rising edge of  
.
DAC Control Bit C3 to Control Bit C0  
Daisy-Chain Control (DSY)  
Control Bit C3 to Control Bit C0 allow control of various functions  
of the DAC, as shown in Table 11. The default settings of the DAC  
at power-on are such that data is clocked into the shift register  
on falling clock edges and daisy-chain mode is enabled. The device  
powers on with a zero-scale load to the DAC register and IOUT lines.  
The DAC control bits allow the user to adjust certain features at  
power-on. For example, daisy-chaining can be disabled if not in  
use, an active clock edge can be changed to a rising edge, and DAC  
output can be cleared to either zero scale or midscale. The user  
can also initiate a readback of the DAC register contents for veri-  
fication.  
DSY allows the enabling or disabling of daisy-chain mode.  
A 1 enables daisy-chain mode; a 0 disables daisy-chain mode.  
When disabled, a readback request is accepted; SDO is auto-  
matically enabled; the DAC register contents of the relevant  
DAC are clocked out on SDO; and, when complete, SDO is  
disabled again.  
CLR  
Hardware  
The default setting for the hardware  
and DAC output to zero code. A 1 in the HCLR bit allows the  
CLR  
Bit (HCLR)  
CLR  
bit is to clear the registers  
pin to clear the DAC outputs to midscale, and a 0 clears to  
zero scale.  
Control Register (Control Bits = 1101)  
Active Clock Edge (SCLK)  
While maintaining software compatibility with single-channel  
current output DACs (AD5426/AD5432/AD5443), these DACs  
also feature additional interface functionality. Set the control bits  
to 1101 to enter control register mode. Figure 47 shows the  
contents of the control register, the functions of which are  
described in the following sections.  
The default active clock edge is a falling edge. Write a 1 to this  
bit to clock data in on the rising edge, or a 0 to clock it in on the  
falling edge.  
DB15 (MSB)  
DB0 (LSB)  
C3  
C2  
C1  
C0  
C0  
C0  
1
DB7  
DB6  
DB5  
DB4  
DB3  
DB2  
DB1  
DB0  
0
0
0
0
CONTROL BITS  
DATA BITS  
Figure 44. AD5429 8-Bit Input Shift Register Contents  
DB15 (MSB)  
C3 C2  
DB0 (LSB)  
0 0  
C1  
DB9  
DB8  
DB7  
DB6  
DB5  
DB4  
DB3  
DB2  
DB1  
DB0  
DB2  
X
CONTROL BITS  
DATA BITS  
Figure 45. AD5439 10-Bit Input Shift Register Contents  
DB15 (MSB)  
C3 C2  
DB0 (LSB)  
C1  
DB11  
DB10  
DB9  
DB8  
DB7  
DB6  
DB5  
DB4  
DB3  
DB1  
DB0  
CONTROL BITS  
DATA BITS  
Figure 46. AD5449 12-Bit Input Shift Register Contents  
DB15 (MSB)  
1
DB0 (LSB)  
X X  
1
0
SDO2 SDO1  
DSY HCLR SCLK  
X
X
X
X
CONTROL BITS  
Figure 47. Control Register Loading Sequence  
Rev. C | Page 20 of 32  
 
 
 
 
AD5429/AD5439/AD5449  
When control bits = 0000, the device is in no operation mode.  
This may be useful in daisy-chain applications in which the user  
does not want to change the settings of a particular DAC in the  
chain. Write 0000 to the control bits for that DAC; subsequent  
data bits are ignored.  
SYNC  
Function  
SYNC  
is an edge-triggered input that acts as a frame synchron-  
ization signal and chip enable. Data can be transferred into the  
device only while  
SYNC  
SYNC  
is low. To start the serial data transfer,  
SYNC  
should be taken low, observing the minimum  
Standalone Mode  
falling edge to SCLK falling edge setup time, t4.  
After power-on, write 1001 to the control word to disable daisy-  
Daisy-Chain Mode  
SYNC  
chain mode. The first falling edge of  
clock counter to ensure that the correct number of bits are  
SYNC  
resets the serial  
Daisy-chain mode is the default power-on mode. To disable the  
daisy-chain function, write 1001 to the control word. In daisy-  
chain mode, the internal gating on SCLK is disabled. SCLK is  
shifted in and out of the serial shift registers. A  
edge  
during the 16-bit write cycle causes the device to abort the  
current write cycle.  
SYNC  
continuously applied to the input shift register when  
is  
low. If more than 16 clock pulses are applied, the data ripples  
out of the shift register and appears on the SDO line. This data  
is clocked out on the rising edge of SCLK (this is the default; use  
the control word to change the active edge) and is valid for the  
next device on the falling edge of SCLK (default). By connecting  
this line to the SDIN input on the next device in the chain,  
a multidevice interface is constructed. For each device in the  
system, 16 clock pulses are required. Therefore, the total number  
of clock cycles must equal 16n, where n is the total number of  
devices in the chain. See Figure 4.  
After the falling edge of the 16th SCLK pulse, data is automat-  
ically transferred from the input shift register to the DAC. For  
another serial transfer to take place, the counter must be reset  
SYNC  
by the falling edge of  
.
LDAC  
Function  
LDAC  
The  
function allows asynchronous and synchronous  
updates to the DAC output. The DAC is asynchronously updated  
when this signal goes low. Alternatively, if this line is held perma-  
nently low, an automatic or synchronous update mode is selected,  
whereby the DAC is updated on the 16th clock falling edge when  
SYNC  
When the serial transfer to all devices is complete,  
should  
be taken high. This prevents additional data from being clocked  
into the input shift register. A burst clock containing the exact  
SYNC  
the device is in standalone mode, or on the rising edge of  
when the device is in daisy-chain mode.  
SYNC  
number of clock cycles can be used, after which  
can be  
, data is automatically  
LDAC  
Software  
Load-and-update mode can also serve as a software update func-  
LDAC  
Function  
SYNC  
taken high. After the rising edge of  
transferred from the input shift register of each device to the  
addressed DAC.  
tion, irrespective of the voltage level on the  
pin.  
Table 11. DAC Control Bits  
C3  
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
C2  
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
C1  
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
C0  
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
DAC  
A and B  
A
A
A
B
B
B
A and B  
A and B  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
Function Implemented  
No operation (power-on default)  
Load and update  
Initiate readback  
Load input register  
Load and update  
Initiate readback  
Load input register  
Update DAC outputs  
Load input registers  
Disable daisy-chain  
Clock data to shift register on rising edge  
Clear DAC output to zero scale  
Clear DAC output to midscale  
Control word  
Reserved  
No operation  
Rev. C | Page 21 of 32  
 
AD5429/AD5439/AD5449  
See the ADSP-21xx user manual at www.analog.com for details  
SYNC  
Table 12 shows the setup for the SPORT control register.  
MICROPROCESSOR INTERFACING  
on clock and frame  
frequencies for the SPORT register.  
Microprocessor interfacing to the AD54xx family of DACs is  
through a serial bus that uses standard protocol and is compatible  
with microcontrollers and DSP processors. The communication  
channel is a 3-wire interface consisting of a clock signal, a data  
signal, and a synchronization signal. The AD5429/AD5439/  
AD5449 require a 16-bit word, with the default being data valid  
on the falling edge of SCLK; however, this is changeable using  
the control bits in the data-word.  
Table 12. SPORT Control Register Setup  
Name  
TFSW  
INVTFS  
DTYPE  
ISCLK  
TFSR  
Setting  
Description  
1
1
00  
1
1
Alternate framing  
Active low frame signal  
Right-justify data  
Internal serial clock  
Frame every word  
Internal framing signal  
16-bit data-word  
ADSP-21xx-to-AD5429/AD5439/AD5449 Interface  
ITFS  
SLEN  
1
The ADSP-21xx family of DSPs is easily interfaced to an AD5429/  
AD5439/AD5449 DAC without the need for extra glue logic.  
Figure 48 is an example of a serial peripheral interface (SPI)  
between the DAC and the ADSP-2191. The MOSI (master output,  
slave input) pin of the DSP drives the serial data line, SDIN.  
1111  
ADSP-BF5xx-to-AD5429/AD5439/AD5449 Interface  
The ADSP-BF5xx family of processors has an SPI-compatible port  
that enables the processor to communicate with SPI-compatible  
devices. A serial interface between the BlackFin® processor and  
the AD5429/AD5439/AD5449 DAC is shown in Figure 50. In  
this configuration, data is transferred through the MOSI pin.  
SYNC  
SPIxSEL  
is driven from a port line, in this case  
.
AD5429/AD5439/  
AD5449  
ADSP-2191*  
SPIxSEL  
*
SYNC  
SDIN  
SCLK  
SYNC  
SPIxSEL  
is driven by the  
pin, which is a reconfigured  
MOSI  
SCK  
programmable flag pin.  
AD5429/AD5439/  
AD5449*  
ADSP-BF5xx*  
*ADDITIONAL PINS OMITTED FOR CLARITY.  
SYNC  
SDIN  
SCLK  
SPIxSEL  
MOSI  
Figure 48. ADSP-2191 SPI-to-AD5429/AD5439/AD5449 Interface  
The ADSP-2101/ADSP-2103/ADSP-2191 processor incorporates  
channel synchronous serial ports (SPORT). A serial interface  
between the DAC and DSP SPORT is shown in Figure 49. In this  
interface example, SPORT0 is used to transfer data to the DAC  
shift register. Transmission is initiated by writing a word to the Tx  
register after SPORT has been enabled. In a write sequence, data  
is clocked out on each rising edge of the DSP serial clock and  
clocked into the DAC input shift register on the falling edge of  
its SCLK. Updating of the DAC output takes place on the rising  
SCK  
*ADDITIONAL PINS OMITTED FOR CLARITY.  
Figure 50. ADSP-BF5xx-to-AD5429/AD5439/AD5449 Interface  
A serial interface between the DAC and the DSP SPORT is shown  
in Figure 51. When SPORT is enabled, initiate transmission by  
writing a word to the Tx register. The data is clocked out on each  
rising edge of the DSP serial clock and clocked into the DAC  
input shift register on the falling edge of its SCLK. The DAC  
output is updated by using the transmit frame synchronization  
SYNC  
edge of the  
signal.  
AD5429/AD5439/  
AD5449*  
ADSP-2101/  
ADSP-2103/  
SYNC  
(TFS) line to provide a  
signal.  
ADSP-2191  
*
TFS  
DT  
SYNC  
AD5429/AD5439/  
AD5449*  
ADSP-BF5xx*  
SDIN  
TFS  
DT  
SYNC  
SCLK  
SCLK  
SDIN  
SCLK  
SCLK  
*ADDITIONAL PINS OMITTED FOR CLARITY.  
Figure 49. ADSP-2101/ADSP-2103/ADSP-2191 SPORT-to-  
AD5429/AD5439/AD5449 Interface  
*ADDITIONAL PINS OMITTED FOR CLARITY.  
Figure 51. ADSP-BF5xx SPORT-to-AD5429/AD5439/AD5449 Interface  
Communication between two devices at a given clock speed is  
possible when the following specifications are compatible: frame  
SYNC  
SYNC  
delay and frame  
data setup-and-hold, and SCLK width. The DAC interface expects  
SYNC  
setup-and-hold, data delay and  
a t4 (  
minimum.  
falling edge to SCLK falling edge setup time) of 13 ns  
Rev. C | Page 22 of 32  
 
 
 
 
 
 
AD5429/AD5439/AD5449  
80C51/80L51-to-AD5429/AD5439/AD5449 Interface  
valid on the falling edge of SCK. Serial data from the 68HC11  
is transmitted in 8-bit bytes with only eight falling clock edges  
occurring in the transmit cycle. Data is transmitted MSB first.  
A serial interface between the DAC and the 80C51/80L51 is  
shown in Figure 52. TxD of the 80C51/80L51 drives SCLK of  
the DAC serial interface, and RxD drives the serial data line, SDIN.  
P1.1 is a bit-programmable pin on the serial port and is used to  
To load data to the DAC, leave PC7 low after the first eight bits  
are transferred and perform a second serial write operation to  
the DAC. PC7 is taken high at the end of this procedure.  
SYNC  
drive  
. When data is to be transmitted to the switch, P1.1  
is taken low. The 80C51/80L51 transmit data in 8-bit bytes only;  
therefore, only eight falling clock edges occur in the transmit cycle.  
If the user wants to verify the data previously written to the input  
shift register, the SDO line can be connected to MISO of the  
SYNC  
To load data correctly to the DAC, P1.1 is left low after the first  
eight bits are transmitted, and then a second write cycle is initiated  
to transmit the second byte of data. Data on RxD is clocked out  
of the microcontroller on the rising edge of TxD and is valid on  
the falling edge of TxD. As a result, no glue logic is required  
between the DAC and microcontroller interface. P1.1 is taken  
high following the completion of this cycle. The 80C51/80L51  
provide the LSB of the SBUF register as the first bit in the data  
stream. The DAC input register requires its data with the MSB  
as the first bit received. The transmit routine should take this  
requirement into account.  
MC68HC11, and, with  
low, the shift register clocks data  
out on the rising edges of SCLK.  
MICROWIRE-to-AD5429/AD5439/AD5449 Interface  
Figure 54 shows an interface between the DAC and any  
MICROWIRE-compatible device. Serial data is shifted out  
on the falling edge of the serial clock, SK, and is clocked into  
the DAC input shift register on the rising edge of SK, which  
corresponds to the falling edge of the DAC SCLK.  
MICROWIRE*  
AD5429/AD5439/  
AD5449*  
SK  
SO  
CS  
SCLK  
AD5429/AD5439/  
80C51  
*
SDIN  
AD5449*  
SYNC  
TxD  
RxD  
P1.1  
SCLK  
SDIN  
SYNC  
*ADDITIONAL PINS OMITTED FOR CLARITY.  
Figure 54. MICROWIRE-to-AD5429/AD5439/AD5449 Interface  
PIC16C6x/7x-to-AD5429/AD5439/AD5449 Interface  
*ADDITIONAL PINS OMITTED FOR CLARITY.  
Figure 52. 80C51/80L51-to-AD5429/AD5439/AD5449 Interface  
The PIC16C6x/7x synchronous serial port (SSP) is configured  
as an SPI master with the clock polarity bit (CKP) = 0. This is  
done by writing to the synchronous serial port control register  
(SSPCON). See the PIC16/17 microcontroller user manual for  
more information. In this example, the I/O port, RA1, is used to  
MC68HC11-to-AD5429/AD5439/AD5449 Interface  
Figure 53 is an example of a serial interface between the DAC  
and the MC68HC11 microcontroller. The SPI on the MC68HC11  
is configured for master mode (MSTR) = 1, clock polarity bit  
(CPOL) = 0, and clock phase bit (CPHA) = 1. The SPI is configured  
by writing to the SPI control register (SPCR); see the MC68HC11  
user manual. The SCK of the MC68HC11 drives the SCLK of  
the DAC interface; the MOSI output drives the serial data line  
(SDIN) of the AD5429/AD5439/AD5449.  
SYNC  
provide a  
signal and enable the serial port of the DAC. This  
microcontroller transfers only eight bits of data during each serial  
transfer operation; therefore, two consecutive write operations  
are required. Figure 55 shows the connection diagram.  
PIC16C6x/7x*  
SCK/RC3  
AD5429/AD5439/  
AD5449*  
SCLK  
MC68HC11*  
AD5429/AD5439/  
AD5449*  
SDI/RC4  
RA1  
SDIN  
PC7  
SCK  
SYNC  
SCLK  
SDIN  
SYNC  
MOSI  
*ADDITIONAL PINS OMITTED FOR CLARITY.  
Figure 55. PIC16C6x/7x-to-AD5429/AD5439/AD5449 Interface  
*ADDITIONAL PINS OMITTED FOR CLARITY.  
Figure 53. MCH68HC11/68L11-to-AD5429/AD5439/AD5449 Interface  
SYNC  
The  
is being transmitted to the AD5429/AD5439/AD5449, the  
line is taken low (PC7). Data appearing on the MOSI output is  
signal is derived from a port line (PC7). When data  
SYNC  
Rev. C | Page 23 of 32  
 
 
 
 
AD5429/AD5439/AD5449  
layout reduces the effects of feedthrough on the board. A micro-  
strip technique is by far the best method, but its use is not always  
possible with a double-sided board. In this technique, the compo-  
nent side of the board is dedicated to the ground plane, and  
signal traces are placed on the soldered side.  
PCB LAYOUT AND POWER SUPPLY DECOUPLING  
In any circuit where accuracy is important, careful considera-  
tion of the power supply and ground return layout helps to  
ensure the rated performance. The printed circuit board on  
which the AD5429/AD5439/AD5449 is mounted should be  
designed so that the analog and digital sections are separate  
and confined to certain areas of the board. If the DAC is in a  
system where multiple devices require an AGND-to-DGND  
connection, the connection should be made at one point only.  
The star ground point should be established as close as possible  
to the device.  
It is good practice to use compact, minimum lead-length PCB  
layout design. Leads to the input should be as short as possible  
to minimize IR drops and stray inductance.  
The PCB metal traces between VREFx and RFBx should also be  
matched to minimize gain error. To maximize high frequency  
performance, the I-to-V amplifier should be located as close as  
possible to the device.  
The DAC should have ample supply bypassing of 10 μF in parallel  
with 0.1 μF on the supply, located as close as possible to the  
package, ideally right up against the device. The 0.1 μF capacitor  
should have low effective series resistance (ESR) and low effective  
series inductance (ESI), such as the common ceramic types of  
capacitors that provide a low impedance path to ground at high  
frequencies, to handle transient currents due to internal logic  
switching. Low ESR, 1 μF to 10 μF tantalum or electrolytic  
capacitors should also be applied at the supplies to minimize  
transient disturbance and filter out low frequency ripple.  
EVALUATION BOARD FOR THE DAC  
The evaluation board consists of an AD5429/AD5439/AD5449  
DAC and a current-to-voltage amplifier, the AD8065. Included  
on the evaluation board is a 10 V reference, the ADR01. An  
external reference can also be applied via an SMB input.  
The evaluation kit consists of a CD-ROM with self-installing  
PC software to control the DAC. The software allows the user  
to write a code to the device.  
Components, such as clocks, that produce fast-switching signals,  
should be shielded with digital ground to avoid radiating noise  
to other parts of the board, and they should never be run near  
the reference inputs.  
Power Supplies for the Evaluation Board  
The board requires 12 V and +5 V supplies. The +12 V VDD  
and −12 V VSS are used to power the output amplifier; the +5 V  
supply is used to power the DAC (VDD) and transceivers (VCC).  
Avoid crossover of digital and analog signals. Traces on opposite  
sides of the board should run at right angles to each other. This  
Both supplies are decoupled to their respective ground plane  
with 10 μF tantalum and 0.1 μF ceramic capacitors.  
Rev. C | Page 24 of 32  
 
 
AD5429/AD5439/AD5449  
Evaluation Board Schematic and Artwork  
Figure 56. Schematic of the Evaluation Board  
Rev. C | Page 25 of 32  
AD5429/AD5439/AD5449  
Figure 57. Component-Side Artwork  
Figure 58. Silkscreen—Component-Side View (Top)  
Rev. C | Page 26 of 32  
AD5429/AD5439/AD5449  
Figure 59. Solder-Side Artwork  
Rev. C | Page 27 of 32  
AD5429/AD5439/AD5449  
OVERVIEW OF AD54xx DEVICES  
Table 13.  
Part No.  
AD5424  
AD5426  
AD5428  
AD5429  
AD5450  
AD5432  
AD5433  
AD5439  
AD5440  
AD5451  
AD5443  
AD5444  
AD5415  
AD5405  
AD5445  
AD5447  
AD5449  
AD5452  
AD5446  
AD5453  
AD5553  
AD5556  
AD5555  
AD5557  
AD5543  
AD5546  
AD5545  
AD5547  
Resolution  
No. DACs  
INL (LSB)  
Interface  
Parallel  
Serial  
Parallel  
Serial  
Serial  
Serial  
Parallel  
Serial  
Parallel  
Serial  
Serial  
Serial  
Serial  
Parallel  
Parallel  
Parallel  
Serial  
Serial  
Serial  
Serial  
Serial  
Parallel  
Serial  
Parallel  
Serial  
Parallel  
Serial  
Parallel  
Package1  
RU-16, CP-20  
RM-10  
RU-20  
Features  
8
1
1
2
2
1
1
1
2
2
1
1
1
2
2
2
2
2
1
1
1
1
1
2
2
1
1
2
2
0.25  
0.25  
0.25  
0.25  
0.25  
0.5  
0.5  
0.5  
0.5  
0.25  
1
10 MHz BW, 17 ns CS pulse width  
10 MHz BW, 50 MHz serial  
10 MHz BW, 17 ns CS pulse width  
10 MHz BW, 50 MHz serial  
10 MHz BW, 50 MHz serial  
10 MHz BW, 50 MHz serial  
10 MHz BW, 17 ns CS pulse width  
10 MHz BW, 50 MHz serial  
10 MHz BW, 17 ns CS pulse width  
10 MHz BW, 50 MHz serial  
10 MHz BW, 50 MHz serial  
10 MHz BW, 50 MHz serial  
8
8
8
8
RU-10  
UJ-8  
RM-10  
RU-20, CP-20  
RU-16  
10  
10  
10  
10  
10  
12  
12  
12  
12  
12  
12  
12  
12  
14  
14  
14  
14  
14  
14  
16  
16  
16  
16  
RU-24  
UJ-8  
RM-10  
RM-8  
RU-24  
CP-40  
0.5  
1
1
10 MHz BW, 50 MHz serial  
10 MHz BW, 17 ns CS pulse width  
10 MHz BW, 17 ns CS pulse width  
10 MHz BW, 17 ns CS pulse width  
10 MHz BW, 50 MHz serial  
10 MHz BW, 50 MHz serial  
10 MHz BW, 50 MHz serial  
1
RU-20, CP-20  
RU-24  
1
1
0.5  
1
2
1
RU-16  
UJ-8, RM-8  
RM-8  
UJ-8, RM-8  
RM-8  
RU-28  
10 MHz BW, 50 MHz serial  
4 MHz BW, 50 MHz serial clock  
4 MHz BW, 20 ns WR pulse width  
4 MHz BW, 50 MHz serial clock  
4 MHz BW, 20 ns WR pulse width  
4 MHz BW, 50 MHz serial clock  
4 MHz BW, 20 ns WR pulse width  
4 MHz BW, 50 MHz serial clock  
4 MHz BW, 20 ns WR pulse width  
1
1
1
RM-8  
RU-38  
2
2
RM-8  
RU-28  
2
2
RU-16  
RU-38  
1 RU = TSSOP, CP = LFCSP, RM = MSOP, UJ = TSOT.  
Rev. C | Page 28 of 32  
 
 
AD5429/AD5439/AD5449  
OUTLINE DIMENSIONS  
5.10  
5.00  
4.90  
16  
9
8
4.50  
4.40  
4.30  
6.40  
BSC  
1
PIN 1  
1.20  
MAX  
0.15  
0.05  
0.20  
0.09  
0.75  
0.60  
0.45  
8°  
0°  
0.30  
0.19  
0.65  
BSC  
SEATING  
PLANE  
COPLANARITY  
0.10  
COMPLIANT TO JEDEC STANDARDS MO-153-AB  
Figure 60. 16-Lead Thin Shrink Small Outline Package [TSSOP]  
(RU-16)  
Dimensions shown in millimeters  
ORDERING GUIDE  
Model1  
Resolution  
INL (LSB)  
0.5  
0.5  
0.5  
0.5  
0.5  
0.5  
0.5  
0.5  
0.5  
0.5  
0.5  
0.5  
1
Temperature Range  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
−40°C to +125°C  
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  
16-Lead TSSOP  
16-Lead TSSOP  
16-Lead TSSOP  
16-Lead TSSOP  
16-Lead TSSOP  
16-Lead TSSOP  
Evaluation Board  
Evaluation Board  
Evaluation Board  
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  
RU-16  
RU-16  
RU-16  
RU-16  
RU-16  
RU-16  
AD5429YRU  
8
8
8
8
8
8
AD5429YRU-REEL  
AD5429YRU-REEL7  
AD5429YRUZ  
AD5429YRUZ-REEL  
AD5429YRUZ-REEL7  
AD5439YRU  
AD5439YRU-REEL  
AD5439YRU-REEL7  
AD5439YRUZ  
AD5439YRUZ-REEL  
AD5439YRUZ-REEL7  
AD5449YRU  
AD5449YRU-REEL  
AD5449YRU-REEL7  
AD5449YRUZ  
AD5449YRUZ-REEL  
AD5449YRUZ-REEL7  
EVAL-AD5429EBZ  
EVAL-AD5439EB  
EVAL-AD5449EBZ  
10  
10  
10  
10  
10  
10  
12  
12  
12  
12  
12  
12  
1
1
1
1
1
1 Z = RoHS Compliant Part.  
Rev. C | Page 29 of 32  
 
 
 
AD5429/AD5439/AD5449  
NOTES  
Rev. C | Page 30 of 32  
AD5429/AD5439/AD5449  
NOTES  
Rev. C | Page 31 of 32  
AD5429/AD5439/AD5449  
NOTES  
©2004–2010 Analog Devices, Inc. All rights reserved. Trademarks and  
registered trademarks are the property of their respective owners.  
D04464-0-4/10(C)  
Rev. C | Page 32 of 32  

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