The finger’s resistance varies depending on how much it is bent, so Brandon used an LM339 comparator to determine the mouse clicks. For the actual mouse interface he used the guts of a Gyration ...

I have an induction heater circuit with operational amplifiers LM358A and LM339. The induction heater circuit consists a bridge rectifier, IGBT, PWM controller + MOSFET module, LC tank circuit, ...

️ Comparator + Optocoupler Method ️ 🟦 Components 1. Comparator (e.g., LM339) 2. Optocoupler (e.g., 4N25) 3. Input signal source 4. Frequency counter or microcontroller 🟦 Working ...