Title :
A CMOS self-powered monolithic light direction sensor with SAR ADC
Author :
Hongjiang Song ; Zhijian Lu ; Tao Luo ; Christen, Jennifer Blain ; Hongyi Wang
Author_Institution :
Sch. of Electr., Comput., & Energy Eng., Arizona State Univ., Tempe, AZ, USA
Abstract :
A light direction sensor, SAR ADC, and energy harvesting photodiodes are integrated on a single chip based fabricated in a 0.18 μm process. No external power supply is needed for the chip to operate. Micro-scale metal baffles create on-chip shadowing for sensing light direction. The frequency of the SAR ADC automatically varies adapting to the harvested power. A current compensation circuit is presented to improve the precision to 7 ENOB. In addition, the chip works when solar intensity is greater than 45 mW/cm2.
Keywords :
CMOS image sensors; analogue-digital conversion; energy harvesting; monolithic integrated circuits; photodiodes; solar absorber-convertors; 7 ENOB; CMOS self-powered monolithic light direction sensor; SAR ADC; energy harvesting photodiodes; microscale metal baffles; on-chip shadowing; sensing light direction; size 0.18 mum; Metals; Mirrors; Optical sensors; Photoconductivity; Photodiodes; Power supplies; System-on-chip; Light Direction Detection; Photo Sensor; SAR ADC; Self-Powered;
Conference_Titel :
System-on-Chip Conference (SOCC), 2014 27th IEEE International
Conference_Location :
Las Vegas, NV
DOI :
10.1109/SOCC.2014.6948900
