LTC1293/LTC1294/LTC1296
Single Chip 12-Bit
Data Acquisition System
FEATURES
s
DESCRIPTIO
s
s
s
s
s
Software Programmable Features
Unipolar/Bipolar Conversion
Differential/Single Ended Inputs
MSB-First or MSB/LSB Data Sequence
Power Shutdown
Built-In Sample and Hold
Single Supply 5V or
鹵5V
Operation
Direct 4-Wire Interface to Most MPU Serial
Ports and All MPU Parallel Ports
46.5kHz Maximum Throughput Rate
System Shutdown Output (LTC1296)
The LTC1293/4/6 is a family of data acquisition systems
which contain a serial I/O successive approximation A/D
converter. It uses LTCMOS
TM
switched capacitor technol-
ogy to perform either 12-bit unipolar, or 11-bit plus sign
bipolar A/D conversions. The input multiplexer can be
configured for either single ended or differential inputs (or
combinations thereof). An on-chip sample and hold is
included for all single ended input channels. When the
LTC1293/4/6 is idle it can be powered down in applica-
tions where low power consumption is desired. The
LTC1296 includes a System Shutdown Output pin which
can be used to power down external circuitry, such as
signal conditioning circuitry prior to the input mux.
The serial I/O is designed to communicate without external
hardware to most MPU serial ports and all MPU parallel
I/O ports allowing up to eight channels of data to be
transmitted over as few as three wires.
LTCMOS
TM
is a trademark of Linear Technology Corporation
KEY SPECIFICATIO S
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Resolution ..................................................... 12 Bits
Fast Conversion Time ............ 12碌s Max Over Temp.
Low Supply Current ........................................ 6.0mA
TYPICAL APPLICATI
12-Bit Data Acquisition System with Power Shutdown
R
B
5.1k
2N3906
+
R1
10k
1/4 LT1014
R2
1.2M
CH0
CH1
CH2
CH3
V
CC
SSO
CLK
CS
鈥?/div>
R2
1.2M
C2
1碌F
350鈩?STRAIN
GAUGE BRIDGE
CH4
CH5
CH6
CH7
COM
LTC1296
D
OUT
D
IN
REF
+
REF
鈥?/div>
AGND
V
鈥?/div>
THREE ADDITIONAL STRAIN GAUGE INPUTS
CAN BE ACCOMMODATED USING THE OTHER
AMPLIFIERS IN THE LT1014
DGND
U
74HC04
47碌F
+5V
MPU
1N4148
LTC1293 TA01
UO
U
1
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