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LTC1448
Dual 12-Bit Rail-to-Rail
Micropower DAC
–
+
–
+
12-BIT
DAC B
RAIL-TO-RAIL
VOLTAGE
OUTPUTS
12-BIT
DAC A
POWER-ON
RESET
24-BIT
SHIFT
REG
AND
DAC
LATCH
P
DIN
2
7
REF
4
6
1448 TA01
CLK
1
CS/LD
3
8
VOUT B
5
VOUT A
VCC
GND
2.7V TO 5.5V
Functional Block Diagram: 12-Bit Rail-to-Rail Dual DAC
Differential Nonlinearity
vs Input Code
CODE
0
–0.5
DNL
ERROR
(LSB)
–0.4
–0.2
–0.1
0
0.5
0.2
1024
2048 2560
1448 TA02
–0.3
0.3
0.4
0.1
512
1536
3072 3584 4095
FEATURES
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SO-8 Package
s
12-Bit Resolution
s
Buffered True Rail-to-Rail Voltage Output
s
External Reference Input Can Be Tied to VCC
s
Output Swings from 0V to VREF
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3V and 5V Supply Operation
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Schmitt Trigger on Clock Input Allows Direct
Optocoupler Interface
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Power-On Reset Clears DACs to 0V
s
3-Wire Serial Interface
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Maximum DNL Error: 0.5LSB
s
Low Cost
The LTC
1448 is a dual rail-to-rail voltage output, 12-bit
digital-to-analog converter (DAC). It includes rail-to-rail
output buffer amplifiers and an easy-to-use 3-wire serial
interface. It is available in 8-pin SO and PDIP packages and
provides the smallest footprint of any dual 12-bit DAC.
The LTC1448 has an external reference input pin (REF)
and its outputs swing from 0V to REF. The REF input can
be tied to VCC providing rail-to-rail operation from supplies
of 2.7V to 5.5V. (For devices with internal reference see the
LTC1446 data sheet.) The LTC1448 dissipates 2.5mW
from a 5V supply.
The low power supply current and the small SO-8 package
make the LTC1448 ideal for battery-powered applications.
DESCRIPTION
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, LTC and LT are registered trademarks of Linear Technology Corporation.
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Digital Calibration
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Industrial Process Control
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Automatic Test Equipment
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Cellular Telephones
APPLICATIONS
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TYPICAL APPLICATION
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