a
FEATURES
On-Chip Latches for Both DACs
+5 V to +15 V Operation
DACs Matched to 1%
Four Quadrant Multiplication
TTL/CMOS Compatible
Latch Free (Protection Schottkys not Required)
APPLICATIONS
Digital Control of:
Gain/Attenuation
Filter Parameters
Stereo Audio Circuits
X-Y Graphics
V
DD
DB0
DATA
INPUTS
DB7
CMOS Dual 8-Bit
Buffered Multiplying DAC
AD7528
FUNCTIONAL BLOCK DIAGRAM
V
REF
A
R
FB
A
INPUT
BUFFER
OUT A
LATCH
DAC A
AGND
DAC A/
DAC B
CS
WR
LATCH
DGND
DAC B
CONTROL
LOGIC
AD7528
R
FB
B
OUT B
V
REF
B
GENERAL DESCRIPTION
ORDERING GUIDE
1
Model
2
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.
Separate on-chip latches are provided for each DAC to allow
easy microprocessor interface.
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.
The device operates from a +5 V to +15 V power supply, dis-
sipating only 20 mW of power.
Both DACs offer excellent four quadrant multiplication charac-
teristics with a separate reference input and feedback resistor for
each DAC.
PRODUCT HIGHLIGHTS
Temperature
Ranges
–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
–55°C to +125°C
–55°C to +125°C
–55°C to +125°C
Relative Gain
Accuracy Error
±
1 LSB
±
1/2 LSB
±
1/2 LSB
±
1 LSB
±
1/2 LSB
±
1/2 LSB
±
1 LSB
±
1/2 LSB
±
1/2 LSB
±
1 LSB
±
1/2 LSB
±
1/2 LSB
±
1 LSB
±
1/2 LSB
±
1/2 LSB
±
4 LSB
±
2 LSB
±
1 LSB
±
4 LSB
±
2 LSB
±
1 LSB
±
4 LSB
±
2 LSB
±
1 LSB
±
4 LSB
±
2 LSB
±
1 LSB
±
4 LSB
±
2 LSB
±
1 LSB
Package
Options
3
N-20
N-20
N-20
P-20A
P-20A
P-20A
R-20
R-20
R-20
Q-20
Q-20
Q-20
Q-20
Q-20
Q-20
AD7528JN
AD7528KN
AD7528LN
AD7528JP
AD7528KP
AD7528LP
AD7528JR
AD7528KR
AD7528LR
AD7528AQ
AD7528BQ
AD7528CQ
AD7528SQ
AD7528TQ
AD7528UQ
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.
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.
NOTES
1
Analog Devices reserves the right to ship side-brazed ceramic in lieu of cerdip. Parts
will be marked with cerdip designator “Q.”
2
Processing 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.
3
N = Plastic DIP; P = Plastic Leaded Chip Carrier; Q = Cerdip; R = SOIC.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
World Wide Web Site: http://www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 1998
AD [ ANALOG DEVICES ]
