24-Bit, 80SPS, 4-Ch (Differential), Pin-Programmable Delta-Sigma ADC for Bridge Sensors

The ADS1232 and ADS1234 (ADS123x) are

precision, 24-bit, analog-to-digital converters (ADCs). With a low-noise

programmable gain amplifier (PGA), a precision delta-sigma ADC, and internal

oscillator. The ADS123x provides a complete front-end solution for bridge sensor

applications including weigh scales, strain gauges, and pressure sensors.

An input multiplexer (MUX) accepts

either two (ADS1232) or four (ADS1234) differential inputs. The ADS1232 also

includes a temperature sensor to monitor ambient temperature. The low-noise PGA has

a selectable gain of 1, 2, 64, or 128, supporting a full-scale differential input of

±2.5V, ±1.25V, ±39mV, or ±19.5mV.

The delta-sigma ADC provides a maximum

of 23.5-bits effective resolution, and supports two data rates: 10SPS (providing

50Hz and 60Hz rejection) and 80SPS. The ADS123x can be clocked externally using an

oscillator or a crystal, or by the internal oscillator.

Offset calibration is performed

on-demand, and the ADS123x can be put in a low-power standby mode or shut off

completely in power-down mode. The ADS123x are operated through simple pin-driven

control—there are no digital registers to program.

Data are output over a two-wire serial

interface that connects directly to the MSP430 and other microcontrollers.