Optical Receiver Using Noise Cancelling With an Integrated Photodiode in 40 nm CMOS Technology

Abstract

A transimpedance amplifier (TIA) based on an inverting voltage amplifier with a shunt feedback resistor using a noise cancelling technique is presented. The TIA is followed by two stages of differential limiting amplifiers and the last stage is a 50 Ω differential output driver to provide an interface to the measurement setup. The TIA shows a measured optical sensitivity of -20.7 dBm for a BER of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-9</sup> using an external photodiode (PD). Another chip with the same TIA and an integrated N+/Psub PD is also introduced. The optical receiver achieves a measured transimpedance gain of 78 dBΩ, 1.5 GHz bandwidth and a measured input referred noise current density of 7.2 pA/√Hz up to 1.5 GHz. The power consumption of the TIA is only 4.1 mW and the complete chip dissipates 12 mW for a single 1 V supply voltage.