ADC GX7794 Replaceable AD7794 in Power Measurements

Modern electronic measurement, the measurement accuracy has more and more high requirements, at the same time, due to the portable measuring instruments of the battery power supply, the overall power consumption of the circuit also has high requirements. This paper focuses on a domestic high-performance ADC to replace the AD7794 for power measurement equipment, the ADC device is extremely small, easy to use in a variety of portable equipment.

GX7794 integrated programmable gain amplifier (PGA) and low-drift on-chip voltage reference, the output data rate can be configured for 4.17SPS to 890SPS.50Hz/60Hz while suppressing the option of its high-precision analog-to-digital conversion function, the input analog power signals (eg, current, voltage signals) converted to digital signals. For current measurement, a current transformer or shunt is usually used to convert the current signal to a small voltage signal suitable for its input range. For voltage measurement, the voltage signal can be connected directly.

The GX7794 then continuously samples and converts these signals at a set sampling frequency. By processing and calculating these digital signals, current and voltage values can be obtained. Its high-precision feature ensures the accuracy and reliability of the measurement results, which can meet the demand for accurate measurement and monitoring of power. Meanwhile, it can also cooperate with microcontroller or other digital processing systems to realize the functions of data storage, transmission and further analysis. Its features are as follows:

- Programmable gain: 1/2/4/8/16/32/64/128

- RMS noise.

  20nV at 4.17SPS (gain=128)

  63nV at 16.7SPS (gain=128)

  21.0 noiseless bits at 4.17SPS (gain=1)

- Offset drift: 5nV/°C (gain=128); gain drift: 1ppm/°C

- 1.17V/2.5V internal reference voltage source with 4ppm/°C drift

- Power Supply

  AVDD:2.7V to 5.25V

  DVDD: 2.7V to 5.25V

- Package: 24-pin TSSOP