#the4thLichuangcompetition#18650 charger + LED light

Note: * is required.

[Please fill in during the registration stage↓]
* Briefly introduce the work: 18650 charger + power bank + LED light.
[Please fill in during the competition stage↓]
* 1. Details of the work:
Use IP5306 lithium battery charge and discharge chip and PT4115LED constant current driver IC. The input charging voltage should not exceed 5.5V, the charging current can reach 2A, the discharge current is 2.4A, short press 0.5 Seconds can activate the USB power bank function and battery indicator light. Press it twice to turn off the power bank function. Press and hold for 3 seconds to control the LED light to turn on and off (to use the LED light function, you must be under the USB power bank function).
* 2. Describe the challenges faced by the work and the problems it solves;
the challenge is how to make IP5306 not only charge and boost but also control LED lighting. The first version thought that as long as the PT4115 pin 3 is given a voltage higher than 0.3V Now you can control the LED. After the proofing came back, welding test found that the LED would have visible flicker and the LED control was out of control. By connecting C9 to 5V voltage and testing for 1 minute without flickering, I thought the debugging was done. Sometimes it can light up and sometimes it can light up. The problem of not lighting up was found by testing pin 5 of IP5306 and found that a short press will produce a voltage output of more than 1V, and a long press for 3 seconds will produce an output of more than 3V. I thought about adding a 2.7V voltage regulator between pin 5 and pin 3 of PT4115. The tube should be able to solve the problem. When I tested it in the dormitory at night, the LED light would automatically turn off after 5 minutes. I thought about it for a while and grounded C9 to make pin 3 of PT4115 a stable voltage. It should be able to solve the problem. After the modification the next day, the test for 4 hours met the expected requirements.
The picture below is the first version of the schematic
! [Schematic.png] The picture below is the final schematic after modification
! [Untitled.png] * 3. Describe the key points involved in the hardware and software parts of the work;
  do not take too much time in manual welding Long, the welding temperature should not be too high, and the components will basically be successful the first time according to the drawing requirements! The picture below shows the first version of the PCB board. Heat dissipation was not considered at the time, and two lamps burned out after using it for a few hours. The second version enhanced heat dissipation and modified the LED layout.
![IMG_20190822_165335.jpg] Remember not to install the battery upside down, and the input voltage should not exceed 5.5V. I have suffered a loss. Look at the picture below, the IC was burned out.
![IMG_20190829_092739.png] * 4. List of materials for the work;
details The BOM is in the project attachment
! [bom.png] * 5. Upload the picture of the work; (the competition logo must be on the PCB and take a photo and upload it, if not, it will be deemed as giving up the competition)
![18650+LED front.png] ![18650+LED Reverse.png] ![Picture.png] * 6. Demonstrate your work and record it as a video for upload; (The content of the video must include: introduction of the work; function demonstration; performance test; close-up shot of the competition logo on the PCB. Failure to do so will be deemed as abandonment Participation)
Video link: [https://v.youku.com/v\_show/id\_XNDMzNzA1OTk2OA==.html?spm=a2h3j.8428770.3416059.1](https://v.youku.com/v_show/id_XNDMzNzA1OTk2OA ==.html?spm=a2h3j.8428770.3416059.1)
   7. Open source documents.
All open source: [https://lceda.cn/editor#id=|8acb707871cd411a942ae20daf27af2d|d1e5d2d9c6ec46 8ea7858b44969c71ba](https://lceda.cn/editor#id=%7C8acb707871cd411a942ae20daf27af2 d%7Cd1e5d2d9c6ec468ea7858b44969c71ba)