Replacing the AD7124, GXSC ADC GX7124 Is Applied to Industrial Sensors

Industrial sensors are a type of industrial automation component used to detect physical quantities such as temperature, pressure, position, and flow rate and output electrical signals. In industrial sites, sensor signals are weak (for example, the output of a pressure sensor is only at the millivolt level), environmental interference is severe (power-frequency noise, motor surges), and multi-channel synchronization requirements are complex—these problems amplify measurement errors and require high-precision analog-to-digital conversion units to complete signal conversion and output accurate, stable digital signals.

The GXSC GX7124, a 24-bit, 16-channel device, can accurately detect microvolt-level signal changes, supports simultaneous 50/60 Hz rejection, can filter out power grid clutter interference, and ensures stable acquisition data without jitter. The GX7124 integrates multiple functions to reduce system cost and component count in sensor measurement applications. It features a low-noise, programmable gain amplifier, a single-cycle settling digital filter, and an internal oscillator.

The GX7124 also provides a built-in low-drift voltage reference and two matched programmable excitation current sources. The input multiplexer supports 8 differential inputs. In addition, the multiplexer integrates sensor burn-out detection, thermocouple voltage bias, system monitoring, and general-purpose digital I/O. The PGA provides selectable gains up to 128 V/V. Its main performance advantages are as follows:

• The GX7124 supports PIN TO PIN replacement of the AD7124.

• Number of channels: 16 single-ended/8 differential pairs

• Output rate: up to 19.2 kSPS

• High integration:

› Integrated internal reference: temperature drift 8 ppm/°C, 2.5 V

› Programmable differential amplifier (integrated high-impedance PGA): 0.02% initial accuracy

› Integrated 2-channel 0.1% matching IDAC

› Integrated bias voltage and open-wire detection

› Integrated 2°C accuracy temperature sensor

• Supports simultaneous 50/60 Hz rejection

• Single-cycle settling and automatic channel scanning

• Supports SPI CRC verification

• Digital supply: 2.7 V~5.25 V

• Analog supply: unipolar (2.7 V~5.25 V) & bipolar (±2.5 V)

• Package: 5.00 mm × 5.00 mm QFN (32-pin)

• Operating temperature range: –40°C to +125°C