Foundation V3S mini core board

Foundation V3S ultra-mini core board
 
1. Features
Ultra-mini size, 22mmx31.55mm
integrated ultra-thin TF card slot on the back
through 2 board-to-board connectors to lead out all IO (except SDC0, used for the TF card slot), through the connector Provide 3.3V power supply
and 3.3V, 3.0V, 1.8V, 1.2V test points for easy debugging
 
. 2. The project consists of a
core board
expansion development board, including 4-port USB HUB, 100M Ethernet, 40PIN LCD RGB interface (TIKY’s tube Pin definition), UARTx1, I2Cx1, IO, etc.
can use the uboot and kernel of Lichee PI zero. SPI and some IO need to change the DTS. Please refer to the attachment.
 
Front:
Back:
Insert:
Display:
 
3. Processing
1) Tried at the beginning For 4-layer boards, because the overall size is too small, it is difficult to route traces unless lamination is abandoned.
Later, it was changed to a 6-layer board (Jia Lichuang did not have BGA requirements at that time). In fact, 6-layer boards are also quite difficult to wire. It’s not that there are not enough wiring layers, but that the through holes take up too much area (be careful when making small boards if you don’t use blind and buried vias!!!).
Fortunately, JLC 6-layer boards have a hole-in-the-plate process. It saves a lot of through-hole positions, and even double-sided device pads can be connected through each other.
 
2) USB, EPHY and CSI all have differential impedance, corresponding to the 6-layer impedance requirement: JLC06161H-3313
 
4.
Double-sided soldering, first solder one side of the TF card (high-temperature solder paste), and then use the heating table if possible; then solder V3S One side (medium temperature solder paste), heat gun.