IP6805U QI charging board

#Solution verification board based on Injoinic IP6805U wireless charging SOC

##Main features:

*Maximum 5W output power

*Compatible with WPC V1.2.4 protocol

*Support foreign object detection (FOD)

*Internally integrated power MOS

*Integrated voltage/current demodulation

*Minimalist peripheral circuit

[IP6805U Technical Manual](http://www.injoinic.com/wwwroot/uploads/files/20200214/61c3f62b65d561368400a2d0cc2b3a3c.pdf)

##Foreign object detection (FOD) function test: see engineering attachment

###Others: (Basically nonsense, just scroll down if you are too lazy to read it)

About temperature:

I originally wanted to test the temperature of the 2.5W receiving end (CP2021 (Nanjing Coolpo Micro)) after working for 30 minutes. I thought the internal integrated power MOS might generate a lot of heat (I originally planned to stick a heat sink on the back). As a result, in the winter in the north, the power of less than 2.5W can't heat up at all, and the thermocouple of the multimeter on hand is also broken, so I just give up (manual funny).

Resonant capacitor & coil:

I use NPO capacitors (4 100nf in parallel, a total of 400nf), which is actually quite expensive (7 yuan for 10 pieces). It is mainly for good looks. If you don't mind the appearance, you can use CCB (see the technical manual for details).

The coil uses the A11 coil of the QI standard (a lot of Taobao).

Interface:

The main reason for using the micro interface is that I haven't entered the typec era (I have the castrated version of Honor 8), and the C port in my hand is 16PIN, and I don't want to waste it. If you don't want to buy a micro, you can directly remove a USB cable. There is a pad for the power cord on the PCB.

Pad:

The pad of the coil seems a bit small, but it's not unusable (funny). If you think it's small, remember to change it before placing an order.

Emmmm, no more nonsense. This is my first open source, I don't have much experience, thank you for reading.

I wish you success once and never solder!