A large-signal blocker robust transimpedance amplifier for coexisting radio receivers in 45nm CMOS

A baseband transimpedance amplifier for coexisting radio receivers is presented. It exploits active feedback to improve out-of-band large-signal attenuation, minimizing in-band distortion due to close-in blockers. A fully-differential prototype of the proposed solution has been designed and implemented in 45nm CMOS. Experimental results show that it can handle linearly single tones of ±10mA, withstanding blocking currents of ±9mA at 50MHz and beyond before reaching P1dB in a 10MHz bandwidth. The fabricated device occupies 0.25mm², largely MOM finger capacitors, and draws 17mA from a 2.5V supply.