A CMOS Fully Differential Optoelectronic Receiver for Short-Range LiDAR Sensors

Abstract

This article presents an optoelectronic receiver IC with on-chip avalanche photodiode (APD) realized in a 180-nm CMOS process for the applications of indoor-monitoring light detection and ranging (LiDAR) sensors. As an on-chip optical detector, a CMOS <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{p}^{+}$ </tex-math></inline-formula> /n-well APD is integrated, thereby enabling to avoid unwanted signal distortion from bond-wires and electrostatic discharge (ESD) protection diodes. Various circuit techniques are exploited in this work, including the dual-feedback folded-cascode differential transimpedance amplifier (DFD-TIA) to achieve fully differential signaling from the input stage, an active single-to-differential (ASD) converter to minimize the inherent mismatches of the preceding DFD-TIA, a cross-coupled inverter-based postamplifier (CI-PA) to improve the symmetry of the output voltage swings, and a two-stage differential amplifier with negative impedance compensation (TDA-NIC) to obtain gain-boosting and wide bandwidth characteristics. Measured results of the proposed optoelectronic receiver IC demonstrate 87-dB <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\cdot \Omega $ </tex-math></inline-formula> transimpedance gain, 577-MHz bandwidth, 15.4-pA/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\surd $ </tex-math></inline-formula> Hz noise current spectral density, 4.18- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{A}_{{\mathrm {pp}}}$ </tex-math></inline-formula> minimum detectable signal that corresponds to the maximum detection range of 10 m, and 50.6-mW power dissipation from a 1.8-V supply. Optical measurements utilizing an 850-nm laser diode with the average power of 10 mW reveal that the proposed optoelectronic receiver IC successfully recovers narrow 1-ns light pulses with the full-width at half-maximum (FHWM) of 840 ps even at the short distance of 50 cm. Hence, this work provides a potential solution for low-cost, low-power short-range LiDAR sensors.

Topics & Concepts