SGL8022W Card Light

Cause: ~~It was my classmate's birthday, and I wanted to make him a gift during LCSC's "Warm Winter Creations for the New Year" event. LCSC happened to be holding a "Warm Winter Creations for the New Year" contest, and I happened to have a chip I wanted to make a touch lamp, so I took the opportunity.

Thus, this touch lamp project came about.

Planning:
Main Controller: Since it's a touch lamp, it definitely needs to support touch. After researching online, I decided to use the SGL8022W as the main controller, which directly supports touch. (SGL8022W chip manual: https://item.szlcsc.com/82803.html)

Power Supply: The first version decided to use a TP4056 (chip manual: https://item.szlcsc.com/772193.html) + 18650 for power supply, plus a USB 6PIN for charging the 18650 and powering the lamp. The second version uses a CR2032 power supply plus a USB 6PIN power supply scheme. The first version used a Schottky diode circuit for automatic power switching, but the second version, due to laziness, simply changed it to manual power switching (dog head).

Voltage regulation: An AMS1117-3.3 (chip datasheet: https://item.szlcsc.com/20102431.html) was used for the 3.3V input voltage regulation scheme.



Schematic Diagram Section:
1. SGL8022W: Directly referenced the typical circuit provided in the chip datasheet, but considering that the control scheme does not need to be modified later, OT1 and OT2 were fixed as having no brightness memory and a gradual brightening/dimming mode
![image.png] 2. First version of TP4056: Referencing the typical circuit provided in the chip datasheet and the circuit design in https://blog.csdn.net/eletronicfish/article/details/131671126 (thanks to the author for the open source)
![TP4056 circuit.png] 3. Second version of CR2032: A total of 4 cells were used, with two cells connected in series and two connected in parallel
![battery.png]
4. AMS1117-3.3: Referencing the typical circuit provided in the chip datasheet and a tiny bit of memory (dog head)
![AMS1117-3.3.png]
5. USB Input: USB_TYPE_C_6PIN
![USB.png]
6. LED Section: Eight white LEDs connected in parallel
![LED.png] 7. Manual Power Supply Selection: A mechanical selection mechanism was used
![Power Supply Selection.png] 8. Automatic Power Supply Selection: The circuit design in https://blog.csdn.net/eletronicfish/article/details/131671126 was referenced
![Power Supply Selection 2.png]
PCB Design
Component Packages: Most components were packaged in 0805 for easy hand soldering (dog head).

First version: Four-layer board. Signal traces were placed on the top and bottom layers. Inner layer 1 was VCC, and inner layer 2 was GND. Major components were placed on the top layer, such as the circuitry surrounding the TP4056 and the SGL8022W. The bottom layer contained eight LEDs and touch pads.
Touch Pads:
![Touch Pads.png]
Second version: After learning that color silkscreen printing only supported two-layer boards, the design was redrawn. Except for a few places where thin lines were used, the line width was generally 30mil. A picture of Li Xingyun was added to the top layer (he's really handsome...)
![Top layer silkscreen.png] A picture of Zhang Tian Anxing and Happy New Year was added to the bottom layer (~~to pass censorship~~)
![Bottom layer silkscreen.png]
3D shell:
First version: Too basic, too lazy to explain.
Second version: First, generate the shell frame using the board outline, then adjust the specific values:
![3D values.png] (depending on the situation)
Next, cut grooves on the side according to the PCB:
![3D groove.png] To allow light to pass through the bottom, cut grooves at the bottom
![Bottom groove.png] To fix the PCB, add screw posts
![Bottom groove.png] The shell is done (dog head)

SGL8022W characteristics
![SGL8022W.png]
Soldering:
Solder small components first, then large components. Be careful not to brittle the USB. The LED in the practical version is drawn backwards, too lazy to correct it. Remember to reverse it when you solder it yourself.

Video address:
https://www.bilibili.com/video/BV1g64y1w7y1/