Delta-sigma ADC with PGA and AC excitation

The Texas Instrument ADS1235-Q1 is a precision, 7200-SPS, delta-sigma ADC with an integrated PGA. This device also incorporates diagnostic features such as PGA overrange and reference monitors. The ADC gives high-accuracy, zero-drift conversion data for high-precision equipment, including strain gauges, weigh scales, and resistive pressure sensors.

The ADC has signal and reference multiplexers that support three differential signal inputs and two reference inputs. The ADC also includes a low-noise PGA that provides gains of one, 64, and 128. The ADC also has a 24-bit ΔΣ modulator and programmable digital filter.

The high-impedance inputs (1GOhm) of the PGA decrease measurement error that is created by sensor loading.

The ADC supports AC-bridge excitation to exclude the drift errors from the sensor wiring. The ADC gives the clock control signals for the ac-excitation operation.

The flexible digital filter is programmable for single-cycle settled conversions and provides 50Hz and 60Hz line cycle rejection at the same time.

The device is available in a 5mm x 5mm VQFN package and is specified across the –40C to +125C temperature range.