A Low Power Analog Baseband for IoT Applications in 40 nm CMOS

A low power highly reconfigurable analog baseband (ABB) for internet of things (IoT) application is presented in this paper. To overcome the problems caused by low intrinsic gain in deep sub-micron CMOS technology, thick gate-oxide transistors technique and active balun techniques are utilized to boost the voltage gain of the operational amplifier. Moreover, a smart common-mode feedback bias circuit is used to make the operational amplifier (OPAMP) robust to process variations and mismatch. The presented ABB provides a maximum gain of approximately 80 dB with a step of 1dB and covers a cutoff frequency range from 1.25 MHz to 20MHz. The ABB has been implemented in 40 nm CMOS and the simulation result shows that it consumes 9.8mW power from a 1.5V supply voltage with a core die area of 0.26mm2.