Title :
Monolithic optical position encoder with on-chip photodiodes
Author :
Aubert, Philippe ; Oguey, Henri J. ; Vuilleumier, Raymond
Author_Institution :
Centre Suisse d´´Electron. et de Microtech., Neuchatel, Switzerland
fDate :
4/1/1988 12:00:00 AM
Abstract :
A system that combines light sensors and analog and digital parts on the same CMOS chip has been fabricated. The optical and electrical properties of various photodiodes, which are fully compatible with a standard CMOS technology, are discussed. The current comparators use CMOS-compatible lateral bipolar transistors. The optical encoder also comprises a signal processor for code conversion, a serial or parallel output, and a self-test function. A 14-channel circuit which senses light signals at 880 nm with a power of 0.3-3 mW/cm2 has been fabricated. Response time is shorter than 1 μs at all illumination levels. This circuit operates in the temperature range -55 to +125°C. Its current consumption is 8 mA at 5 V
Keywords :
CMOS integrated circuits; angular measurement; encoding; integrated logic circuits; photodetectors; position measurement; -55 to 125 C; 1 mus; 14 bits; 5 V; 8 mA; 880 nm; ASIC; CMOS chip; CMOS-compatible lateral bipolar transistors; VLSI; code conversion; current comparators; current consumption; custom ICs; electrical properties; light sensors; on-chip photodiodes; optical encoder; optical position encoder; optical shaft encoders; parallel output; response time; self-test function; serial output; signal processor; standard CMOS technology; system on chip; temperature range; Bipolar transistors; Built-in self-test; CMOS technology; Circuits; Delay; Lighting; Optical sensors; Photodiodes; Sensor systems; Signal processing;
Journal_Title :
Solid-State Circuits, IEEE Journal of
