360‐μW 4.1‐dB NF CMOS MedRadio receiver RF front‐end with current‐reuse Q ‐boosted resistive feedback LNA for biomedical IoT applications

Summary In this paper, a low‐power low‐noise complementary metal‐oxide semiconductor (CMOS) receiver RF front‐end (RFFE) that employs a current‐reuse Q ‐boosted resistive feedback low‐noise amplifier (RFLNA) is proposed for 401 to 406 MHz medical device radio‐communication service band IoT applications. By employing a series RLC input matching network, the proposed RFLNA has the advantages of both the conventional RFLNA and the inductively degenerated common‐source LNA without using large on‐chip spiral inductors at the sources of the main transistors. The proposed active mixer utilizes a current‐reuse transconductor, in which a p‐channel metal‐oxide semiconductor (PMOS) transistor performs a current‐bleeding function to reduce direct current (DC) and flicker noise in the switching stage of the active mixer. The proposed receiver RFFE is implemented in a 65‐nm CMOS process and achieves a voltage gain of 30.9 dB, noise figure of 4.1 dB, S11 of less than −10 dB, and IIP3 of −22.9 dBm. It operates at a supply voltage of 1 V with bias currents of 360 μA. The active die area is 0.4 mm × 0.35 mm.