Pulse oximeters, a type of photoplethysmography (PPG) sensor, are electronic devices that measure a person’s blood-oxygen saturation (SpO 2) and heart-rate (HR) levels. Since their inception in the ...

One of the first frustrating situations a beginning microcontroller programmer will come across is the issue of debouncing switches. Microcontrollers are faster than switches, and the switch has yet ...

Part 1 of this series provided an overview on using reflectometry for a pulse plethysmograph (PPG) waveform and described the physical and physiological principles at work. Much attention has been ...