Disassembly of the knockoff TWS headset charging box

dcexpert

Disassembly of the knockoff TWS headset charging box [Copy link]

 

I bought a cheap knockoff TWS headset a few months ago and have been planning to take it apart. A few days ago, I finally found an opportunity to take apart the charging box and share it with you.

Earphones and charging case

The earphones are fixed with glue, which is not easy to remove, so I first removed the charging box. The charging box is completely fixed with buckles (four in total). After finding the key position, you can disassemble it. After disassembly, it is as shown below. It mainly consists of the charging board, battery and shell.

The charging box capacity written on the earphone shell is 400mAH, but the actual battery is marked as 200mAH

The charging board is very simple, with only a chip on the front. It seems that the BOM cost of the batch will not exceed 0.5 yuan.

The chip model is MP3402

MP3402C is a dedicated chip for Bluetooth headset charging, integrating charging management module, LED power display module, synchronous boost discharge management and other functions. A brief introduction of the chip:

You need to press a button to charge, and you can't put it in automatic charging. The blue LED indicates boost mode, and the red LED indicates USB charging.

yang_alex

I don't see how the power is transmitted. Electromagnetic coupling? Or contact?

dcexpert

yang_alex posted on 2020-1-14 11:15 I can't figure out how the power is transmitted. Electromagnetic coupling? Or contact?

There is a dedicated plug, wired mode, not wireless charging

chunyang

These knockoff headphones are actually sold for 9.9 yuan...

chunyang

I seldom use headphones anymore, but I still pursue sound quality. I am still using the aiwa I bought in the 1990s. I have compared headphones used in mobile phones, including those from Nokia, Huawei, Xiaomi, etc., and the sound quality of the old aiwa is still better.

dcexpert

chunyang posted on 2020-1-14 11:39 I rarely use headphones, but I still pursue sound quality. I am still using the aiwa I bought in the 1990s. I have compared headphones used by mobile phones, including Nokia, Huawei, Xiaomi, etc....

The sound quality is still better with wired ones, wireless ones are just more convenient to use. Most people may not be familiar with Aiwa's products now.

wsmysyn

yang_alex posted on 2020-1-14 11:15 I can't figure out how the power is transmitted. Electromagnetic coupling? Or contact?

Contact point charging, the better charging case also has an MCU chip, the two contact points of the earphones serve as both charging ports and communication interfaces,

The charging current is not large.

xutong

The subsequent headphones should eventually move to a single-chip solution