a
FEATURES
12-Bit CMOS DAC with
On-Chip Voltage Reference
Output Amplifier
Three Selectable Output Ranges
–5 V to +5 V, 0 V to +5 V, 0 V to +10 V
Serial Interface
300 kHz DAC Update Rate
Small Size: 16-Lead DIP or SOIC
Nonlinearity: 1/2 LSB T
MIN
to T
MAX
Low Power Dissipation: 100 mW Typical
APPLICATIONS
Process Control
Industrial Automation
Digital Signal Processing Systems
Input/Output Ports
REFOUT
LC MOS
12-Bit Serial DACPORT
AD7243
FUNCTIONAL BLOCK DIAGRAM
V
DD
2
2R
R
OFS
2R
V
OUT
12 - BIT DAC
REFIN
12
AGND
AD7243
DAC LATCH
12
DGND
INPUT SHIFT REGISTER
V
SS
SDIN CLR BIN/ SCLK SYNC LDAC DCEN SDO
COMP
GENERAL DESCRIPTION
The AD7243 is a complete 12-bit, voltage output, digital-to-
analog converter with output amplifier and Zener voltage refer-
ence on a monolithic CMOS chip. No external trims are
required to achieve full specified performance.
The output amplifier is capable of developing +10 V across a
2 kΩ load. The output voltage ranges with single supply opera-
tion are 0 V to +5 V or 0 V to +10 V, while an additional bipo-
lar
±
5 V output range is available with dual supplies. The ranges
are selected using the internal gain resistor.
The data format is natural binary in both unipolar ranges, while
either offset binary or two’s complement format may be selected
in the bipolar range. A
CLR
function is provided which sets the
output to 0 V in both unipolar ranges and in the two’s comple-
ment bipolar range, while with offset binary data format, the
output is set to –REFIN. This function is useful as a power-on
reset as it allows the output to be set to a known voltage level.
The AD7243 features a fast versatile serial interface which
allows easy connection to both microcomputers and 16-bit digi-
tal signal processors with serial ports. The serial data may be
applied at rates up to 5 MHz allowing a DAC update rate of
300 kHz. A serial data output capability is also provided which
allows daisy chaining in multi-DAC systems. This feature allows
any number of DACs to be used in a system with a simple
4-wire interface. All DACs may be updated simultaneously
using
LDAC.
The AD7243 is fabricated on Linear Compatible CMOS
(LC
2
MOS), an advanced, mixed technology process. It is pack-
aged in 16-lead DIP and 16-lead SOIC packages.
PRODUCT HIGHLIGHTS
1. Complete 12-Bit DACPORT
®
The AD7243 is a complete, voltage output, 12-bit DAC on
a single chip. The single chip design is inherently more
reliable than multichip designs.
2. Single or Dual Supply Operation.
3. Minimum 3-wire interface to most DSP processors.
4. DAC Update Rate–300 kHz.
5. Serial Data Output allows easy daisy-chaining in multiple
DAC systems.
DACPORT is a registered trademark of Analog Devices, Inc.
REV. A
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.
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., 2000
AD [ ANALOG DEVICES ]
