ADS1232 24 bit ultra low noise analog to digital converter

DESCRIPTION

The ADS1232 and ADS1234 are precision 24-bit analog-to-digital converters (ADCs). The ADS1232 / 4 features an onboard, low noise programmable gain amplifier (PGA), precision delta-sigma ADC and internal oscillator to provide a complete front-end solution for bridge sensor applications, including electronic scales, strain gauges and pressure sensors.

The input multiplexer accepts two (ADS1232) or four (ADS1234) differential inputs. The ADS1232 also includes an onboard temperature sensor for monitoring ambient temperature. The onboard low noise PGA features selectable gains of 1, 2, 64 or 128 and supports ±2.5V, ±1.25V, ±39mV or ±19.5mV full-scale differential inputs. The delta-sigma ADC has an effective resolution of 23.5 bits and consists of a 3rd order modulator and a 4th order digital filter. Two data rates are supported: 10SPS (50Hz and 60Hz suppression) and 80SPS. The ADS1232 / 4 can be clocked externally via an oscillator or crystal. There is also an internal oscillator that does not require external components. Offset calibration is performed on demand, and the ADS1232 / 4 can enter low power standby mode or be fully turned off in power down mode. All functions of the ADS1232 / 4 are operated with simple pin drive control. No digital registers can be programmed to simplify software development. The data is output via an easy-to-isolated serial interface that connects directly to the MSP430 and other microcontrollers.

The ADS1232 is available in a TSSOP-24 package and the ADS1234 is available in a TSSOP-28 package. Both are rated over the -40°C to +105°C temperature range.
characteristic
Complete bridge sensor front end
Up to 23.5 valid digits
Onboard, low noise PGA
RMS noise:
17SV, 10SPS (PGA = 128)
44nV at 80SPS (PGA = 128)
Gain = 64, 19.2 bits no noise resolution
More than 100dB while 50Hz and 60Hz suppression