1
LTC1293/LTC1294/LTC1296
129346fs
Single Chip 12-Bit
Data Acquisition System
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.
D
U
ESCRIPTIO
S
FEATURE
■ 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
±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)
U
A
O
PPLICATI
TYPICAL
12-Bit Data Acquisition System with Power Shutdown
CH0
CH1
CH2
CH3
CH4
CH5
CH6
CH7
COM
DGND
–
+
RB
5.1k
R2
1.2M
R1
10k
1/4 LT1014
R2
1.2M
C2
1
F
350
STRAIN
GAUGE BRIDGE
+5V
47
F
1N4148
MPU
LTC1296
VCC
SSO
CLK
CS
DOUT
DIN
REF+
REF–
AGND
V–
THREE ADDITIONAL STRAIN GAUGE INPUTS
CAN BE ACCOMMODATED USING THE OTHER
AMPLIFIERS IN THE LT1014
LTC1293 TA01
2N3906
74HC04
■
Resolution: 12 Bits
■ Fast Conversion Time: 12
s Max Over Temp
■ Low Supply Current: 6.0mA
LTCMOS
TM is a trademark of Linear Technology Corporation
KEY SPECIFICATIO S
U
