CMOS Integrated Circuits for Various Optical Applications

*Sung Min Park*

#### **Abstract**

This chapter presents several CMOS integrated circuits (ICs) realized for various optical applications such as high-definition multimedia interface (HDMI), light detection and ranging (LiDAR), and Gigabit Ethernet (GbE). First, 4-channel 10-Gb/s per channel optical transmitter and receiver array chipset implemented in a 0.13-μm CMOS process are introduced to realize a 10-m active optical cable for HDMI 2.1 specifications. Second, a 16-channel optical receiver array chip is realized in a 0.18-μm CMOS technology for LiDAR applications. Third, a 40-GHz voltagemode mirrored-cascode transimpedance amplifier (MC-TIA) is implemented in a 65-nm CMOS for a feasible 100-GbE application. Even with advanced nano-CMOS technologies, we have suggested novel circuit techniques for optimum performance, such as input data detection (IDD) for low power, feedforward and asymmetric preemphasis for high speed, double-gain feedforward for high gain, selectable equalizer (SEQ) for specific bandwidth, mirrored-cascode for fully differential topology, etc. We believe that these novel circuit techniques help to achieve low-cost, low-power solutions for various optical applications.

**Keywords:** active optical cables, CMOS, GbE, HDMI, integrated circuits, LiDAR, TIA, VCSEL driver

### **1. Introduction**

Optical fibers provide a number of advantages over copper-based electrical cables, which include wide bandwidth, low attenuation, low weight, low electromagnetic interference, low crosstalk between channels, etc. Particularly for high-speed digital interconnects, optical fibers may be the ultimate solution to achieve the desired performance. In this chapter, a few CMOS integrated circuits (ICs) are introduced for various optical applications such as high-definition multimedia interface (HDMI), light detection and ranging (LiDAR), and Gigabit Ethernet (GbE).

Section 2.1 presents 4-channel CMOS transmitter (Tx) and receiver (Rx) chipsets for the applications of 10-Gb/s per channel HDMI active optical cables (AOC). Section 2.2 describes a feedforward voltage-mode CMOS Rx IC for LiDAR applications. Section 2.3 introduces a 40-GHz CMOS Rx IC. Then, conclusion is followed.
