Based on low power consumption MSP430 microcontroller

using new A/D chip AD7745

designed a capacitive differential pressure sensor is used to measure liquid’ different pressure

The design principle of capacitive differential pressure sensor

AD7745 and MSP430’s software and hardware were presented.The results show the measurement results are stable on the 18 bit

resolution is 0.000 1 pF at range of ±100 pF.The output capacitor has a good linear output characteristics and has good repeatability

and also has low cost.So it was suggested that this system has desirable application value.