4-way high-precision filling

Each channel has four display parameters: 1. Voltage, 2. Current, 3. Power, and 4. Joule heat.
Some people might think that a desktop charger doesn't need much precision, and using a 32-bit ADC is a waste. Let me explain: this ADC chip isn't very expensive; you can buy a used one for around 10 RMB on Taobao. I bought a few before, designed a test board, debugged the program, and then it just sat there gathering dust. Recently, I was bored and decided to tinker with some things, hence this project.
The board program is very casual; I just wanted it to work, so it's a bit rough, and the code is rather poor, so I won't open-source it.
The total cost of the board is around 40 RMB, excluding shipping. Thanks to JLCPCB for letting me get it for free.
This ADC chip can output a built-in reference voltage and also output several constant current sources. I tested it before, and the constant current accuracy is about the same as described in the manual—not very high—so I didn't implement it.
The slower the ADC sampling speed, the more stable the data. Value fluctuations and output ripple are related to layout and other factors. In my setup, the bottom layer has more DC-DC converters, and the ADC chip is on the top layer, which might cause some interference. To save time, I designed both parts on one board, but there's a complete ground plane in between for isolation. If you're interested, you can try designing two boards and connecting them.
The ADC sampling speed is quite low; switching between the 8 sampling channels takes a considerable amount of time, so the screen refreshes approximately once per second.
The screen used is a silkscreened T240IT010, driven by SPI and DMA.
The input interface uses an XT30, with a continuous current of 15A, 24V input, and a maximum power of over 300W, making it relatively safe.
The fan selected is a 24V silent fan, size 5050, thickness less than or equal to 10mm.
 
Special note:
Please replace R65, R67, R69, and R71 with 1/18K (or even 1/1000) voltammetric capacitors; please replace R66, R68, R60, and R72 with 1/1000 voltammetric capacitors (or even 1/1000) voltammetric capacitors. Please use C0G capacitors for the 4.7nF capacitor in C4 (other capacitors can be used, but C0G is recommended).