A.2 Audio Amplifier. The audio amplifier part consists of the PAM8403 [3, 4] chip. This chip is a 3W+3W HiFi Class-D amplifier that can operate with only a single 5V supply. The maximum output power ...

A Class D amp is just an oscillator, comparator, and an output stage. All of which can be fulfilled (although poorly) by a single 555. I designed a Class D amp in SPICE, using only a LM339 and ...

An Arduino Due forms the heart of the project, ... The sound signal is passed through an LM4811 headphone amplifier for private listening, and a PAM8403 Class D audio amplifier for the built-in ...

Lilygo TTGO T-Watch-2020 is a thin, ESP32 smartwatch programmable with Arduino that was introduced last year. The WiFi and Bluetooth-connected watch is equipped with a 1.54-inch LCD capacitive touch ...