LM324Analog
Photodiode amplifier
How a transimpedance amplifier built with an LM324 and a feedback resistor converts photodiode current into a voltage proportional to the received light intensity.
Analog
HX711Analog
Load cell front-end with 24-bit ADC
A concise guide to the HX711 from Avia Semiconductor — pinout, two-wire serial interface and internal regulator for connecting a load cell directly to a microcontroller.
LM324Analog
Square wave oscillator
How a square wave oscillator works using an LM324 operational amplifier with positive feedback and a timing capacitor.