An Ultra Low Power CMOS Sigma Delta ADC Modulator for System-on-chip (SoC) Temperature Sensor for Aerospace Applications

Abstract

In the current paper, an accurate with low power consumed sigma delta (ΣΔ) analog to digital converter has been designed for the aerospace applications. The sigma delta ADC has been designed in such a way that it works fine with consumption of low power and high accuracy in the system on chip (SoC) temperature sensor where the analog output from the temperature sensor unit will be the fed to the analog to digital converter. To check the robustness, different parameters with variation has been analyzed. The high gain operational amplifier plays a vital role in the circuits design. Hence, a 30 MHz operational amplifier has also been proposed whose unity gain bandwidth (UGB) has been observed of about 30 MHz, 51.1dB dc gain and slew rate (SR) of about 27.9 V/ μsec. For the proper operation of the circuit, a power supply of +1.3V to -1.3V is used. The proposed sigma delta ADC modulator is showing better results over previously designed modulator in terms of power consumption, error and performance. The design and simulation have been tested with the help of cadence analog design environment with UMC 90nm CMOS process technology.