GXSC GX7793 compatible with AD7793 in high precision temperature control equipment application program

Temperature control technology has become a very important link in various activities such as industry, agriculture, scientific research, aerospace and people‘s lives, especially in the fields of scientific research, aerospace, biomedicine, precision instruments and other areas of temperature control accuracy requirements are extremely high, sometimes extremely demanding.

 

High-precision temperature control equipment based on MCU, ADC and OPA as the core chip, with high precision, simple structure, good stability and so on. In this paper, a domestic ADC in the application of high-precision temperature control equipment, the GX7793 performance can be compatible with the AD7793, with a high degree of integration, stable performance, cost-effective and other advantages.

 

The GX7793 high resolution, low noise, so for the front-end anti-alias filter requirements are also greatly reduced, the highest 16/24-bit. The integrated programmable gain amplifier (PGA) and low-drift on-chip reference voltage source provide a high-accuracy measurement solution for bridge sensors, thermocouples and resistance temperature devices (RTDs).

 

The GX7793 contains a low-noise PGA with selectable gains of 1, 2, 4, 8, 16, 32, 64 and 128, a delta-sigma modulator and digital filters. A low-drift 1.17V or 2.5V reference voltage source is integrated on the chip and two matched excitation current sources (IEXC) are provided for accurate RTD measurements. The device‘s output data rate is configurable from 4.17SPS to 890SPS, with 50Hz/60Hz simultaneous rejection options, while a burn-in current source is provided on the analog input of the sensor connection diagnostic.

 

The GX7793 parameters are as follows:

- Offset Drift: 5nV/C (Gain = 128)

- Gain Drift: 1ppm/°C

- Integral nonlinearity: 2ppm

- 4 differential inputs, internal or external clock

- Available in 16-pin TSSOP package

- Operating temperature range of -40°C to +125°C