GXSC synchronous sampling analog-to-digital converter replaces AD7656 for application in relay protection devices

In the power system, relay protection devices ensure the safe and stable operation of the power grid. Their function is to monitor electrical parameters such as voltage and current of power lines in real time, issue protection instructions quickly and accurately when faults occur, cut off the faulty part, and avoid the expansion of accidents. The signal acquisition module, as the sensing core of the relay protection device, needs to meet certain sampling accuracy, synchronization performance, and response speed.

GXSC‘s analog-to-digital converter has performance advantages such as multi-channel synchronous acquisition, high resolution, low power consumption, and high integration. It is designed specifically for industrial high-precision signal acquisition scenarios, perfectly matching the signal acquisition needs of relay protection devices and becoming the preferred device for the new generation of power relay protection products.

The electrical signals of the power system have the characteristics of strong interference, wide range of values, and multi parameter collaborative monitoring. The GXSC analog-to-digital converter is equipped with six 16 bit fast, low-power successive approximation ADCs, supporting synchronous sampling of six channels. Utilize CONVST signals and internal oscillators to control the conversion process and data acquisition. The three CONVST pins allow for independent synchronous sampling of three pairs of ADCs or synchronous sampling of six channels, meeting the synchronization requirements of the motor drive system.

The GXSC analog-to-digital converter can achieve a maximum sampling rate of 250kSPS and supports high-speed parallel mode or high-speed serial mode, configured through different connection modes of hardware pins. This function creates various connection conditions for the interface connection between the device and the microprocessor or DSP. In terms of power consumption, the chip only uses a 5V power supply to support the conversion of true bipolar input signals of ± 10V and ± 5V. At the same time, the analog-to-digital converter also has an on-chip reference source, which can simplify the application circuit design.

The characteristics of the GXSC analog-to-digital converter are as follows:

True bipolar analog input

• Input signal range: ± 10V/± 5V

• High conversion rate: 250kSPS

Low power consumption: 110mW (250kSPS, 5V power supply)

• On chip reference voltage source and buffer

Parallel and serial interface modes

• High speed serial interface compatible with SPI interface protocol

64 pin LQFP package