CMOS Dual 8-Bit
a
Buffered Multiplying DAC
AD7528
FEATURES
FUNCTIONAL BLOCK DIAGRAM
On-Chip Latches for Both DACs
+5 V to +15 V Operation
V
A
REF
DACs Matched to 1%
R
A
V
FB
DD
Four Quadrant Multiplication
TTL/CMOS Compatible
Latch Free (Protection Schottkys not Required)
DB0
OUT A
DATA
INPUTS
INPUT
BUFFER
LATCH
DAC A
DB7
AGND
APPLICATIONS
AD7528
Digital Control of:
Gain/Attenuation
Filter Parameters
Stereo Audio Circuits
X-Y Graphics
DAC A/
DAC B
R
B
FB
CONTROL
LOGIC
CS
OUT B
WR
LATCH
DAC B
DGND
V
B
REF
GENERAL DESCRIPTION
ORDERING GUIDE1
The AD7528 is a monolithic dual 8-bit digital/analog converter
featuring excellent DAC-to-DAC matching. It is available in
skinny 0.3" wide 20-lead DIPs and in 20-lead surface mount
packages.
Temperature
Ranges
Relative Gain
Accuracy Error
Package
Options3
Model2
AD7528JN –40°C to +85°C
AD7528KN –40°C to +85°C
AD7528LN –40°C to +85°C
±1 LSB
±4 LSB N-20
±1/2 LSB ±2 LSB N-20
±1/2 LSB ±1 LSB N-20
Separate on-chip latches are provided for each DAC to allow
easy microprocessor interface.
AD7528JP
–40°C to +85°C
±1 LSB
±4 LSB P-20A
Data is transferred into either of the two DAC data latches via a
common 8-bit TTL/CMOS compatible input port. Control
input DAC A/DAC B determines which DAC is to be loaded.
The AD7528’s load cycle is similar to the write cycle of a ran-
dom access memory and the device is bus compatible with most
8-bit microprocessors, including 6800, 8080, 8085, Z80.
AD7528KP –40°C to +85°C
AD7528LP –40°C to +85°C
±1/2 LSB ±2 LSB P-20A
±1/2 LSB ±1 LSB P-20A
AD7528JR
–40°C to +85°C
±1 LSB
±4 LSB R-20
AD7528KR –40°C to +85°C
AD7528LR –40°C to +85°C
AD7528AQ –40°C to +85°C
AD7528BQ –40°C to +85°C
AD7528CQ –40°C to +85°C
AD7528SQ –55°C to +125°C ±1 LSB
AD7528TQ –55°C to +125°C ±1/2 LSB ±2 LSB Q-20
AD7528UQ –55°C to +125°C ±1/2 LSB ±1 LSB Q-20
±1/2 LSB ±2 LSB R-20
±1/2 LSB ±1 LSB R-20
±1 LSB
±4 LSB Q-20
±1/2 LSB ±2 LSB Q-20
±1/2 LSB ±1 LSB Q-20
The device operates from a +5 V to +15 V power supply, dis-
sipating only 20 mW of power.
±4 LSB Q-20
Both DACs offer excellent four quadrant multiplication charac-
teristics with a separate reference input and feedback resistor for
each DAC.
NOTES
1Analog Devices reserves the right to ship side-brazed ceramic in lieu of cerdip. Parts
will be marked with cerdip designator “Q.”
2Processing to MIL-STD-883C, Class B is available. To order, add suffix “/883B” to
part number. For further information, see Analog Devices’ 1990 Military Products
Databook.
PRODUCT HIGHLIGHTS
1. DAC-to-DAC matching: since both of the AD7528 DACs are
fabricated at the same time on the same chip, precise match-
ing and tracking between DAC A and DAC B is inherent.
The AD7528’s matched CMOS DACs make a whole new
range of applications circuits possible, particularly in the
audio, graphics and process control areas.
3N = Plastic DIP; P = Plastic Leaded Chip Carrier; Q = Cerdip; R = SOIC.
2. Small package size: combining the inputs to the on-chip DAC
latches into a common data bus and adding a DAC A/DAC B
select line has allowed the AD7528 to be packaged in either a
small 20-lead DIP, SOIC or PLCC.
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
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
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Tel: 781/329-4700
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© Analog Devices, Inc., 1998