An Integrated Optical Sensor Receiver with the Sensitivity of 0.7 μA Fabricated with Standard CMOS Process

Abstract

A fully integrated CMOS receiver front-end with digital output for optical signal processing system is presented. This circuit is composed of trans-impedance amplifier (TIA) for weak optical current detection, post-amplifier for both a linear and limiting amplification, control circuits and the digital output interface. Measured with photodiode which is driven by pulse voltage source, a sensitivity of 0.7μA was achieved. The current model methodology is employed to optimize the noise performance. The front-end consumes the current of 1.5mA with the power supply of 3.3V. The design was done in a low-cost standard CMOS process with 0.6μm featured size, taking area of 600μm×150μm excluding the bonding pads.