Feature: *3.3V or 5.0V DC power supply. *MCU interface: SPI. *Main ADC chip: TM7705 (AD7705 chip is fully compatible) *LM285-2.5 external reference voltage. Part peers using low-end domestic TL-431 is not a number as a reference, temperature stability and accuracy of the level difference. Please sights. *The input circuit with a divided resistor and RC filter, enabling customers to change their own gain range. *Chip programmable gain amplifier with a gain range: 1-128 times. *Chip buffer amplifier input with direct connection Sensor.