Design of CMOS difference amplifier circuit for sigma delta ADC for aerospace applications

Since its inception, MOSFET has found its usage in almost every field. Researchers are consistently trying to shape circuits using CMOS technology which allows consumption of ultra low power instead of high power which was drawn earlier. In the present paper a design of CMOS Difference amplifier circuit which is an integral part of sigma delta ADC has been carried out. The sigma delta amplifier has been used in the design of ultra low power CMOS temperature sensor for aerospace applications. The difference between two inputs results into output in difference amplifier. The high gain operational amplifier plays a key role to design difference amplifier. Hence, an operational amplifier has also been proposed which gives an open loop gain of 48.45dB. The circuits are designed using cadence virtuoso UMC90nm CMOS technology. For the proper operation of the circuit, a power supply of + 1.3V to −1.3 V is used.