LTC1294BCSW Datasheet, PDF (1/28 Pages) Linear Technology – Single Chip 12-Bit Data Acquisition System

LTC1293/LTC1294/LTC1296
Single Chip 12-Bit
Data Acquisition System
FEATURES
■ _{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)}
KEY SPECIFICATIO S
■ _{Resolution: 12 Bits}
■ _{Fast Conversion Time: 12µs Max Over Temp}
■ _{Low Supply Current: 6.0mA}
DESCRIPTIO
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
TYPICAL APPLICATI
12-Bit Data Acquisition System with Power Shutdown
R_B
5.1k
2N3906
R1
10k
350Ω STRAIN
GAUGE BRIDGE
+
1/4 LT1014
–
R2
1.2M
C2
1µF
THREE ADDITIONAL STRAIN GAUGE INPUTS
CAN BE ACCOMMODATED USING THE OTHER
AMPLIFIERS IN THE LT1014
R2
1.2M
CH0
V_CC
CH1
SSO
CH2
CLK
CH3
CS
CH4
D_OUT
LTC1296
CH5
D_IN
CH6
REF⁺
CH7
REF^–
COM
DGND
AGND
V^–
74HC04
MPU
+5V
47µF
1N4148
LTC1293 TA01
129346fs
1