LTC1293/LTC1294/LTC1296 Single Chip 12-Bit Data Acquisition System UFEATUSREDESCRIPTIO ■ Software Programmable Features The LTC1293/4/6 is a family of data acquisition systems Unipolar/Bipolar Conversion which contain a serial I/O successive approximation A/D Differential/Single Ended Inputs converter. It uses LTCMOSTM switched capacitor technol- MSB-First or MSB/LSB Data Sequence ogy to perform either 12-bit unipolar, or 11-bit plus sign Power Shutdown bipolar A/D conversions. The input multiplexer can be ■ Built-In Sample and Hold configured for either single ended or differential inputs (or ■ Single Supply 5V or ±5V Operation combinations thereof). An on-chip sample and hold is ■ Direct 4-Wire Interface to Most MPU Serial included for all single ended input channels. When the Ports and All MPU Parallel Ports LTC1293/4/6 is idle it can be powered down in applica- ■ 46.5kHz Maximum Throughput Rate tions where low power consumption is desired. The ■ System Shutdown Output (LTC1296) 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. UKEY SPECIFICATIO S The serial I/O is designed to communicate without external ■ Resolution: 12 Bits hardware to most MPU serial ports and all MPU parallel ■ Fast Conversion Time: 12µs Max Over Temp I/O ports allowing up to eight channels of data to be ■ Low Supply Current: 6.0mA transmitted over as few as three wires. LTCMOSTM is a trademark of Linear Technology Corporation OUTYPICAL APPLICATI12-Bit Data Acquisition System with Power Shutdown RB 5.1k 2N3906 R2 74HC04 + 1.2M CH0 VCC +5V R1 1/4 LT1014 CH1 SSO 47µF 10k – CH2 CLK CH3 CS 350Ω STRAIN MPU GAUGE BRIDGE CH4 D R2 OUT LTC1296 1N4148 1.2M CH5 DIN CH6 C2 REF+ 1µF CH7 REF– COM AGND THREE ADDITIONAL STRAIN GAUGE INPUTS DGND V– CAN BE ACCOMMODATED USING THE OTHER AMPLIFIERS IN THE LT1014 LTC1293 TA01 129346fs 1