max7219 24X24 dot matrix ping

Description:
The main control chip is max7219, and there are a total of 9 max7219 chips on one PCB board.
The required original device
max7219 chip (new domestically produced (high-end quality)) 0.82 for a certain
1088AS common cathode lattice (0.75 for a certain treasure) is really cheap!
Pin header: Single row female 7p, 0.05×2=0.10 yuan
Resistor: 220kΩ ±5%. 50 pcs 3.33 yuan
capacitors: 0805 100uf 100V. 50 pieces for 3.17 yuan.
Female header: 0.07×18=1.26 yuan.
Total production cost: 0.82×9+0.75×9+0.10+3.33+3.17+1.26=21.99 yuan.
Really cheap!
The PCB board is 9.9cm×9.9cm, which takes advantage of the free prostitution to the extreme.
 
Example
This is the front of a dot matrix screen, showing a Chinese character. The right side of the screen is the data input terminal.
This is viewed from the side. A female header is used here (if the components are damaged, they can be easily replaced, saving time and cost).
 
The board is equipped with a signal output port OUT, which can be cascaded between boards to form a larger dot matrix screen. . There are holes in the four corners of the board to fix the dot matrix screen.