GXSC Monitor Chip Replaces LTC2991 for Voltage and Current Monitoring on Power Supply Boards

In the industrial manufacturing sector, multi-output power supply boards—which serve as power supply units for smart devices—must provide precise output voltage regulation and real-time load current monitoring, as well as perform functions such as power accounting, temperature rise compensation, overvoltage and overcurrent protection, and fault tracing. Traditional power supply monitoring solutions often employ a combination of discrete operational amplifiers and external ADCs, which suffer from issues such as complex circuitry, low sampling accuracy, and a limited number of channels, making it difficult to meet the demands for high-precision monitoring and long-term stable operation of high-precision power supplies.

GXSC has launched an integrated, multi-channel power supply monitoring chip specifically designed for high-precision detection of power supply voltage, current, and temperature. It is tailored to meet the real-time operational monitoring, dynamic parameter acquisition, and fault early warning and protection needs of various power supply boards. This monitoring chip can replace the LTC2991 in both hardware and software, addressing the issues of insufficient accuracy and circuit complexity found in traditional discrete monitoring solutions.

The GXSC monitor integrates 14-bit, eight-channel monitoring functions for voltage, current, and temperature. A single chip can simultaneously perform integrated monitoring of multiple power supply voltages, load currents, and power device temperatures. It supports I²C bus-based cascading of multiple chips to expand the number of channels and offers significant advantages such as minimal peripherals, high accuracy, strong interference resistance, and compact integration.

The GXSC monitor offers a single-ended voltage resolution as low as 305.18 mV, a differential voltage resolution as low as 19.075 μV, and a temperature resolution as low as 0.0625 °C. Within the temperature range of -40°C to 125°C, the chip achieves voltage measurement accuracy better than 0.25%, current measurement accuracy better than 0.75%, and temperature measurement accuracy better than 1.8°C, making it ideal for single or mixed system applications involving voltage, current, and temperature. Key features include:

Capable of measuring 8 single-ended voltage channels, 4 differential voltage (or current) channels, or 4 remote temperature channels

Capable of measuring a single parameter (voltage, current, or temperature) or any combination thereof

Capable of measuring the chip’s own operating voltage and temperature

Single-ended voltage measurement accuracy better than 0.75%, with a resolution of 305.18 μV

Differential voltage and current measurement accuracy better than 0.75%, with a resolution of 19.075 V

Remote temperature measurement accuracy better than 2.0 °C, with a resolution of 0.0625 °C

Internal temperature measurement accuracy better than 1.5 °C, with a resolution of 0.0625 °C

14-bit ADC for voltage/current measurement

PWM dynamic output adjustment

2.9 V to 5.5 V operating voltage range

FC interface with 8 selectable addresses; supports up to 8 devices sharing the same bus

Internal 10 ppm/°C voltage reference

ESD protection rating of 6 kV HBM for V1–V8 analog input pins

Pin-to-pin replacement for the LTC2991