A CMOS infrared wireless optical receiver front-end is presented. A stable variable-gain fully-differential transimpedance feedback amplifier is designed employing a current-mode amplifier as the feedforward gain element. More than a triple variation of the transimpedance gain, from 0.3 k/spl Omega/ to 1 k/spl Omega/, the variable-gain transimpedance amplifier achieves desirable gain-bandwidth independence. For an infrared wireless optical receiver front-end employing the transimpedance amplifier, the optical preamplifier achieves a transimpedance gain of 66 dB/spl Omega/ and a bandwidth of 114 MHz with a 5 pF photodiode capacitance, and a power consumption of 17.4 mW.
['Roger Yubtzuan Chen', 'Tsung-Shuen Hung', 'Chih-Yuan Hung']
A CMOS infrared wireless optical receiver front-end with a variable-gain fully-differential transimpedance amplifier