Hatsune Miku

Color board - Hatsune Bluetooth speaker

A desktop Bluetooth speaker of my own (everything except the sound quality is good)

1. Circuit principle and function

The circuit principle is very easy to understand, and we mainly talk about a few typical circuits.

Taobao search module M18 Bluetooth module can directly find the typical circuit. The price is about 8 yuan, just search it on Taobao and don’t push the link.

The power amplifier part uses the PAM8406 chip, which is not much to say.

The main purpose here is to isolate GND, which is not very effective. The power amplifier chip is not very good, and the sound is still distorted even when the sound is loud.

For the output, I chose a 4Ω 5W speaker. I won’t recommend it here, but in the end I chose a 4Ω 5W speaker. Make sure the terminal is a PH2.0 interface. Taobao link: https://m.tb.cn/h.UE34R4f?tk=nTCDdoscpmP

Switching between Bluetooth and wired via 0 ohm resistor.

Nothing to say here.

This place is an external extension, you can connect it or not, it is designed to look good. Use LM3914 to drive a 2*10 light group, which changes with the sound spectrum. It's actually a rhythm strip. But this part is not easy to use, and I am too lazy to modify it. I will modify it later.

2. Physical pictures