A low-power CMOS power amplifier for implanted biomedical ultra wideband (UWB) applications

This paper presents a low power 3.0 to 6.2 GHz wideband power amplifier for implanted biomedical UWB communication system. The UWB PA employs a common-gate (CG) amplifier for wideband input matching, a common-source amplifier with RC shunt-shunt feedback and bondwire inductor source degeneration to obtain the high and flat gain, good linearity and small chip area, and a source-follower for good output matching. The PA was successfully designed with a 0.18μm CMOS technology. The post-layout simulation results indicated that the proposed PA had an average gain of 11dB, an input return loss(S₁₁) less than -14dB, an output return loss (S₂₂) less than -12dB, and an input 1-dB compression point (IP_1dB) of -14dBm at 4GHz. Moreover, it only consumes a very low power of 13mW at 1.8V supply voltage, and a relatively small chip area of 0.86×0.81 mm².