DAC1423_15 Datasheet, PDF (1/6 Pages) Analog Devices – 4-20MA 10 BIT ISOLATED DIGITAL TO ANALOG CONVERTER

ANALOG
W DEVICES
4-20mA,10-Bit,Isolated
0igitalt-o-AnalogConverter
FEATURES
3.Port Galvanic Isolation
Guaranteed Monotonic 0 to +70oC
Microprocessor Compatible Interface
Increment/Decrement Backup Control
May be Powered from Loop Supply
Low Power: 450mW typ
Output Will Drive on Loads
OBSOLETE Bumpless Transfer, Auto to Manual
APPLICATIONS
Direct Digital Controllers
Ground Loop Elimination in Industrial and Process Control
High Voltage Protected Data Acquisition Systems
Digital Pressure Transducers
Driving Analog Recorders
GENERAL DESCRIPTION
Analog Devices' ISO-DACTM (ISOlated Digital-toAnalog Con-
verter) model DAC1423 is a low power lO-bit DAC with
4-20mA current output, designed specifically for the process
and industrial control industry. Its advanced featUres and
excellent performance make for easy application within new
and existing control systems. The DAC1423 contains a CMOS
holding register, allowing direct interface with microprocessors,
CMOS digital-to-analog converter, voltage-to-voltage isolator
and a voltage-to-loop current converter. The small size and low
Adjustable Offset and Span: The ISO-DAC has offset and span
accuracies of :t2LSB's (:to.2% FSR) each. However, if the user
desires adjustable offset and span, there are provisions for
:t10% adjustment range for each.
High CMV Isolation: The isolation barriers will withstand
1.5V dc continuously, or 1kV rms @ 60Hz for 60 seconds.
The ISO-DAC is designed to meet the IEEE Standard for
Transient Voltage Protection (472-1974: Surge Withstand
Capability). Common Mode Rejection is excellent; typically,
1O3dB @60Hz for a 250n load.
profile (2" X 4" X 0.4") allows much greater functional density
than previously available solutions.
Synchronized: The ISO-DAC may be synchronized to an ex-
DESIGN FEATURES AND USER BENEFITS
Microcomputer Interface: The parallel digital interface is a 5V
CMOS design with independently controllable input latches
and Tri-State* buffers, split into upper and lower sections (an
ternal system clock, multiple DAC1423's may be on synchro-
nized to one another. In the event of loss of external sync, the
DAC1423 will "free run" on its own oscillator.
Isolated Power Out: An internally derived +5V supply is
8-bit and a 2-bit byte) so that 8- or 16-bit bus compatibility
may be achieved.
brought out so that the user may power a small amount of
application circuitry from the DAC1423's power supply.
True 3-Port Isolation: The output connections and power con-
nections are galvanically isolated, both from each other and
from the digital section. Each will accommodate a wide range
of power supply voltages and may be operated from the same
ISA-S50.1: The three terminal output structUre conforms to
the Instrument Society of America Standard ISA-S50.1,
"Compatibility of Analog Signals for Electronic Industrial
Process Instruments."
supply, if desired.
Increment/Decrement: Increment/decrement control is
achieved via the input latch/counter. An internal slow speed
clock is supplied for this operation. Overflow/underflow lock-
out circuitry is used to prevent full scale "bumps" from
occurring.
*Tri-State is a trademark of National Semiconductor Corporation.
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 implica-
tion or otherwise under any patent or patent rights of Analog Devices.
P.O. Box 280; Norwood, Massachusetts 02062 U.S.A.
Tel: [phone]
TWX: 710/394-6577
Telex: 924491
Cables: ANALOG NORWOODMASS
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