Design of a 137dB low power operational amplifier working in weak inversion region using a novel approach

Operational amplifiers are one of the most popular elements in electronic circuit design and their performance including gain, bandwidth and power dissipation are quite important. Although BJT transistor amplifiers provide high gain and broad bandwidth, they usually have very high power consumption. CMOS operational amplifiers working in strong inversion have lower power consumption than BJT amplifiers but they usually have lower gain and narrower bandwidth. However it wasn’t until SPICE models for CMOS transistors developed before researchers could examine transistor behavior in moderate and weak inversion regions. It was then that it became evident that CMOS transistors in moderate and weak inversion have similar behavior to BJTs with very low power usage. In this research using the precise BSIM3 model, we design a two stage high gain (137dB) very low power opamp that operates in weak inversion region.

کلیدواژه ها:

Operational amplifier ، cascade ، weak inversion ، CMOS ، BSIM model