Light-to-digital converter Interuniversitair Micro-Electronica Centrum vzw
Optical sensing on human body providing timely information on health status to common people as well as to practitioners. Photoplethysmogram (PPG) is the most common optical sensing technique and Near-Infrared Spectroscopy (NIRS) is also emerging. Both of these two techniques require high dynamic range because of the low AC/DC ratio. The proposed dual-slope LTC circuitry exploits a new architecture including a reused integrator, which performs a direct light to digital conversion and thus achieves a high DR and low power at the same time. The propose circuit also allows a narrow LED pulse ...