Single Chip 12-Bit Data Acquisition System

The LTC1291 is a data acquisition system that contains a serial I/O successive approximation A/D converter. It uses LTCMOS™ switched capacitor technology to perform a 12-bit unipolar A/D conversion. The input multiplexer can be configured for either single-ended or differential inputs. An on-chip sample-and-hold is included on the “+” input. When the LTC1291 is idle, it can be powered down in applications where low power consumption is desired. An external reference is not required because the LTC1291 takes its reference from the power supply (VCC). All these features are packaged in an 8-pin DIP.

The serial I/O is designed to communicate without external hardware to most MPU serial ports and all MPU parallel I/O ports allowing data to be transmitted over three or four wires. Given the accuracy, ease of use and small package size, this device is well suited for digitizing analog signals in remote applications where minimum number of interconnects, small physical size, and low power consumption are important.

Applications

* Resolution: 12 Bits

* Fast Conversion Time: 12µs Max Over Temp.

* Low Supply Current:

* 6.0mA (Typ) Active Mode

* 10µA (Max) Shutdown Mode

* Built-In Sample-and-Hold

* Single Supply 5V Operation

* Power Shutdown

* Direct 3- or 4-Wire Interface to Most MPU Serial Ports and All MPU Parallel Ports

* Two-Channel Analog Multiplexer

* Analog Inputs Common Mode to Supply Rails

* 8-Pin DIP Package