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a
Quad 8-Bit Voltage Out CMOS DAC
Complete with Internal 10 V Reference
DAC8426
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 617/329-4700 Fax: 617/326-8703
GENERAL DESCRIPTION
The DAC8426 is a complete quad voltage output D/A converter
with internal reference. This product fits directly into any exist-
ing 7226 socket where the user currently has a 10 V external
reference. The external reference is no longer necessary. The
internal reference of the DAC8426 is laser-trimmed to ±0.4%
FEATURES
No Adjustments Required, Total Error 61 LSB Max
Over Temperature
Four Voltage-Output DACs on a Single Chip
Internal 10 V Bandgap Reference
Operates from Single 115 V Supply
Fast 50 ns Data Load Time, All Temperatures
Pin-for-Pin Replacement for PM-7226 and AD7226,
Eliminates External Reference
APPLICATIONS
Process Controls
Multichannel Microprocessor Controlled:
System Calibration
Op Amp Offset and Gain Adjust
Level and Threshold Setting
offering a 25 ppm/°C temperature coefficient and 5 mA of exter-
nal load driving capability.
The DAC8426 contains four 8-bit voltage-output CMOS D/A
converters on a single chip. A 10 V output bandgap reference
sets the output full-scale voltage. The circuit also includes four
input latches and interface control logic.
One of the four latches, selected by the address inputs, is loaded
from the 8-bit data bus input when the write strobe is active
low. All digital inputs are TTL/CMOS (5 V) compatible. The
on-board amplifiers can drive up to 10 mA from either a single
or dual supply. The on-board reference that is always connected
to the internal DACs has 5 mA available to drive external devices.
Its compact size, low power, and economical cost-per-channel,
make the DAC8426 attractive for applications requiring mul-
tiple D/A converters without sacrificing circuit-board space. Sys-
tem reliability is also increased due to reduced parts count.
PMI’s advanced oxide-based, silicon-gate, CMOS process al-
lows the DAC8426’s analog and digital circuitry to be manufac-
tured on the same chip. This, coupled with PMI’s highly stable
thin-film R-2R resistor ladder, aids in matching and tempera-
ture tracking between DACs.
FUNCTIONAL BLOCK DIAGRAM
Verzeichnis
