GXSC Synchronous Sampling Analog-to-Digital Converter Replaces AD7874 for Three-Phase Grid Voltage Detection

As power grids undergo intelligent and digital upgrades, the demand for refined monitoring of distribution networks and real-time control of power quality will continue to rise, further increasing requirements for voltage detection accuracy and efficiency. Three-phase grid voltage detection necessitates synchronous capture of all three-phase voltage signals while balancing detection precision, interference resistance, and multi-scenario adaptability. The analog-to-digital converter (ADC) within the signal acquisition device—specifically its channel count, synchronous sampling capability, conversion accuracy, and anti-interference performance—directly determines the reliability of detection data.

The GXSC four-channel 12-bit 50kSPS synchronous sampling ADC features an on-chip reference voltage source, on-chip clock, and four sample-and-hold amplifiers. This configuration enables simultaneous sampling of four input channels while maintaining their phase relationships. The minimal aperture delay of the four sample-and-hold amplifiers, combined with minimum and maximum threshold settings, enables simultaneous sampling of multiple input channels without introducing phase errors between signals connected to multiple devices. The reference voltage output/input facility also permits multiple devices to be driven by a single reference voltage source.

Thus, the GXSC ADC perfectly addresses the synchronous acquisition requirements for three-phase grid signals (A, B, C phase voltages and neutral line) in three-phase power systems. Compared to multi-chip single-channel ADC configurations, this device eliminates the need for additional synchronization control circuitry, significantly simplifying system architecture.

Product Advantages:

Operates from a 5V supply, supporting conversion of true bipolar input signals up to +10V.

 Features ceramic-encapsulated CDIP28 packaging, compatible with the imported AD7874

Single 5V power supply with ±5V pin compatibility for easy integration

Product dimensions, pinout, and functionality are reference-compatible

Improved signal-to-noise ratio and higher linearity

Lower bipolar zero-level error and reduced positive/negative full-scale error

Enhanced channel isolation

ENOB: 11.8 bits (typical)

 SINAD: 73.4 dB (typical)

SFDR: 95 dB (typical)

INL: ±0.1 LSB (typical)

DNL: ±0.1 LSB (typical)

Operating power consumption: 70 mW (typical)

In summary, this GXSC analog-to-digital converter is particularly suitable for applications requiring relative phase or magnitude information between channels, such as AC motor control and three-phase grid voltage detection. Leveraging its synchronous sampling capability, it accurately captures phase differences and amplitude fluctuations in three-phase voltages, enabling real-time monitoring of anomalies like voltage surges and dips. This enhances the operational status of distribution networks and improves the reliability of power supply.