Review on 🔊 HiLetgo Mini 3W+3W DC 5V Audio Amplifier: Power Amp Module Board for DIY Portable Stereo Amplifiers with Potentiometer by Abidzar Olivas

Read the datasheet for the driver IC used on this board, PAM8403. It states that most applications require ferrite beads on the output leads to prevent RFI as this is a Class D high frequency switching device. Very hot (loss > 1 W) due to the constant high ultrasonic output signal when connected to a capacitive load (piezo tweeter). Installing some small inductors fixed this and now it only draws 4mA at 5V, before this fix it was 230mA and the chip was too hot to touch. It still worked fine in the normal audio range, so I didn't notice the problem until I tried to touch the chip and almost burned my finger. Also, there is little to no built-in filtering of the +5V input, so with a low input you will hear any audible noise in the power supply. With some USB 5V power supplies, this fails quite a bit.