Fully Integrated Line Array Angular Displacement Sensing Chip

• Published in: Sensors (Basel, Switzerland) Vol. 23; no. 5; p. 2431
• Main Authors: Fu, Yunhao, Jiang, Jiaqi, Zhao, Zhuang, Zhao, Zhongyuan, Chen, Kaixin, Tao, Min, Chang, Yuchun, Lo, Guoqiang, Song, Junfeng
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 22.02.2023; MDPI
• Subjects: Accuracy; angular displacement sensing chip; CMOS process; Coding theory; Design; Design and construction; incremental code; Integrated circuits; integrated optoelectronic chip; Light emitting diodes; Principles; pseudo-random code; SAR ADC; Semiconductor chips; Semiconductors; Sensors; China; incremental code; CMOS process; integrated optoelectronic chip; pseudo-random code; angular displacement sensing chip; SAR ADC
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s23052431

The angular displacement sensor is a digital angular displacement measurement device that integrates optics, mechanics, and electronics. It has important applications in communication, servo control, aerospace, and other fields. Although conventional angular displacement sensors can achieve extremely high measurement accuracy and resolution, they cannot be integrated because complex signal processing circuitry is required at the photoelectric receiver, which limits their suitability for robotics and automotive applications. The design of a fully integrated line array angular displacement-sensing chip is presented for the first time using a combination of pseudo-random and incremental code channel designs. Based on the charge redistribution principle, a fully differential 12-bit, 1 MSPS sampling rate successive approximation analog-to-digital converter (SAR ADC) is designed for quantization and subdivision of the incremental code channel output signal. The design is verified with a 0.35 μm CMOS process and the area of the overall system is 3.5 × 1.8 mm2. The fully integrated design of the detector array and readout circuit is realized for the angular displacement sensing.