DS1244

ADS1244 ADS1 244 SBAS273 – DECEMBER 2002 Low-Power, 24-Bit ANALOG-TO-DIGITAL CONVERTER FEATURES q 20-BIT EFFECTIVE RESOLUTION q CURRENT CONSUMPTION: 90µA q ANALOG SUPPLY: 2.5V to 5.25V q DIGITAL SUPPLY: 1.8V to 3.6V q ±5V DIFFERENTIAL INPUT RANGE q 0.0002% INL (TYP), 0.0008% INL (MAX) q SIMPLE 2-WIRE SERIAL INTERFACE q SIMULTANEOUS 50Hz AND 60Hz REJECTION q SINGLE CONVERSIONS WITH SLEEP MODE q SINGLE-CYCLE SETTLING q SELF-CALIBRATION q WELL-SUITED FOR MULTICHANNEL SYSTEMS q EASILY CONNECTS TO THE MSP430 DESCRIPTION The ADS1244 is a 24-bit, delta-sigma Analog-to-Digital (A/D) converter. It offers excellent performance and very low power in an MSOP-10 package and is well suited for demanding high-resolution measurements, especially in portable and other space- and power-constrained systems. A 3rd-order delta-sigma modulator and digital filter form the basis of the A/D converter. The analog modulator has a ±5V differential input range. The digital filter rejects both 50Hz and 60Hz signals, completely settles in one cycle, and outputs data at 15 samples per second. A simple, 2-wire serial interface provides all the necessary control. Data retrieval, self-calibration, and Sleep Mode are handled with a few simple waveforms. When only single conversions are needed, the ADS1244 can be shut down (Sleep Mode) while idle between measurements to dramatically reduce the overall power dissipation. Multiple ADS1244s can be connected together to create a synchronously sampling multichanne...