3.2-inch HDMI portable screen-120HZ

First of all, I would like to thank the owner of Bilibili UP, the financial planner, for helping me analyze and answer questions. Those who are interested in mini portable screens can also check out his work 2.8-inch HDMI display and STC32 development board - Jialichuang EDA open source hardware platform (oshwhub.com )
Product overview:
3.2-inch mini high-resolution
rechargeable built-in 600mA lithium battery
built-in 1W speaker for external sound
120HZ high refresh rate
supports HDMI single line power supply + signal transmission
High-definition ppi reaches 291
Product Parameters:
Display: Size - 3.2 inches Resolution - 800*480 Color format - RGB666
Main control: STC8H1K08
Adapter chip: LT8619C
Power supply: 5V TYPE-C interface or HDMI power supply
Running power consumption: about 1W (excluding speakers)
Battery: 600mA (battery compartment Size: length 44mm*width 28mm*height 6mm)
Speaker: 13mm 1W
circuit board size: 49mm*47mm
Shell size: length 84mm*width 50mm*thickness 11mm 
Production cost:
LT8619C 16 yuan
screen 25 yuan
stc8h1k08 1.5 yuan
battery 10 yuan is enough
cs4344 2.5 yuan
remaining components, 5 yuan is enough,
shipping fee is not included.
The project has been released for free on JLC. If you need it, you can go to JLC to download relevant information, link [3.2-inch HDMI portable screen] - JLC (jlc.com) or Search the 3.2-inch HDMI portable screen
3D introduction picture:
Notes
1. The EEPROM part is not used and is not attached (see the picture below). In addition, R31 and R35 are not attached
. 2. The battery charging current is set by R3, with a maximum of 500ma. BOM default resistance is 3.3K, charging current is 300ma.
Charging current resistance comparison table
3. HDMI power supply precautions (Important!!! Important!!!)
Since the 5V power supply current of the HDMI port of each device that drives the screen is uneven, and the operation of this screen requires about 300MA current, so Please confirm the power supply capability of HDMI, otherwise there is a risk of damaging the equipment.
HDMI5V power also passes through the battery charging chip, so the maximum current is also limited by the charging current in the picture above. Therefore, when the charging current is set to less than 300MA, the battery power is used up and the screen cannot work due to insufficient power supply.
Finally, if HDMI power supply is required, short-circuit the pad of D4 to the pad next to it. (As shown below)
4. The battery compartment size is 44mm long*28mm wide*6mm high. Pay attention to the battery size.
5. Download method: To download the hardware, you need to use a usb to TTL serial port download tool, such as the commonly used CH340 module. The software uses STC-isp. The software download configuration (as shown below)
 
6. The screen defaults to vertical screen. When using it on a computer screen, please Rotate the screen in computer screen settings.