A High-Speed Fully-Integrated VLC Receiver With Large-Area Photodetector

This paper presents a fully integrated visible light communication (VLC) receiver with a large photo-sensitive area optimized for high-speed data transmission. The photodetector (PD) featuring a size of 410 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mu$</tex-math></inline-formula>m × 410 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mu$</tex-math></inline-formula>m is implemented using a P<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup>/N-well/P-sub structure and was segmented into multiple P<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup>/N-well detection cells to enhance the response speed while maintaining high sensitivity. To further extend the overall bandwidth of optical receiver, a continuous-time linear equalizer (CTLE) with negative capacitance technique is incorporated, effectively compensating for the high-frequency gain loss. The proposed VLC receiver was fabricated in CSMC 0.25 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mu$</tex-math></inline-formula>m CMOS technology, and its performance is verified in a VLC test system. The experimental results indicate that this receiver can achieve a data rate of 980 Mbit/s at a bit error rate (BER) of 3.8 × 10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup>.