Synchronous optical detection unmasked

We presented a new silicon optoelectronic receiver in standard CMOS for synchronous detection of light. Two versions were implemented in a 0.7-μm N-well CMOS technology and tested. In the better version, the light-sensitive junctions were the drains of NMOSFETs. This version operated at up to 180 MHz with external 830-nm light pulses of 176 fJ. Our new receiver shows an excellent trade-off between small size, high speed, and good sensitivity, and is therefore an interesting candidate for applications such as digital optical information transfer between VLSI circuits.