Continuous monitoring of heart activity permits measurement of heart rate variability (HRV), a basic parameter of heart health and other diseases.
This Design Idea is a new design of pulse oximetry that excels in its simplicity and functionality. Due to its capabilities, it can be used as a standalone device, able to monitor heart rate and oxygen saturation.
The core of the system is composed of the ultra-bright red LED (KA-3528SURC), infrared LED (VSMB3940X01-GS08), and a photodiode (VBP104SR) sensitive to both wavelengths of light at the same level.
The basic building block of the system is operational amplifier LT6003, which is used in several stages. IC1 is used as a transimpedance amplifier, converting the current generated by the photodiode to a voltage. This stage provides high gain and allows the use of the sensor on almost every part of the body. Op-amp IC2 is connected as an inverting amplifier with a gain of 30.
For more detail: Simple pulse oximetry for wearable monitor
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