FEATURES

20-BIT EFFECTIVE RESOLUTION

CURRENT CONSUMPTION: 90μA

ANALOG SUPPLY: 2.5V to 5.25V

DIGITAL SUPPLY: 1.8V to 3.6V

±5V DIFFERENTIAL INPUT RANGE

0.0002% INL (TYP), 0.0008% INL (MAX)

SIMPLE 2-WIRE SERIAL INTERFACE

SIMULTANEOUS 50Hz AND 60Hz REJECTION

SINGLE CONVERSIONS WITH SLEEP MODE

SINGLE-CYCLE SETTLING

SELF-CALIBRATION

WELL-SUITED FOR MULTICHANNEL SYSTEMS

EASILY CONNECTS TO THE MSP430

APPLICATIONS

HAND-HELD INSTRUMENTATION

PORTABLE MEDICAL EQUIPMENT

INDUSTRIAL PROCESS CONTROL

WEIGH SCALES

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

multichannel measurement system. The ADS1244 is

designed to easily connect to microcontrollers, such as the

MSP430.

The ADS1244 supports 2.5V to 5.25V analog supplies and

1.8V to 3.6V digital supplies. Power is typically less than

270μW in normal operation and less than 1μW during Sleep

Mode.