Homemade Dual USB Car Charging Port

Everyone has experienced the situation of a cell phone running out of power. I bought a car charger online before, a dual USB one, which was OK for charging one cell phone, but slower than a snail for two cell phones. The nominal 2A charger was less than 1.5A in actual tests, and it was seriously overheated and inefficient. This time I am going to make a dual USB 2A DC 5V-36V wide voltage input, output 5V 2A intelligent distribution, add compatibility with Apple cell phone monitoring lines, and perfectly compatible with all 5V charging devices such as Apple, Android, tablets, etc.

1. PCB board
2. Diode
3. wires

Let's check the PCB board diagram firstly.

A diode was soldered onto the IC. During debugging, it was found that when the input voltage was adjusted upward from 0V, the output voltage was always only 3.7V, which was an undervoltage protection. A diode was added to solve the problem. The red circle is the Apple phone monitoring resistor.

Use acrylic to make a cover plate 36*28*5mm fixed plate. The thickness of the acrylic needs to be 10mm to be flush with the cover plate on the car without any steps.

The output voltage is monitored by an oscilloscope and is stable all the way

Input parameters 2 mobile phones are charged. 1 Huawei 5X starts at 62% battery, 1 Apple 4S starts at 22% battery.

The total input current of the two mobile phones is 0.72A. The input voltage is 12.28V = about 8.8W. If the battery of the mobile phone is very low, the input current will increase.

The conversion efficiency of this machine is about 95%, and the heat is not large.

After it is done, prepare to install it in the hole on the left. There are 4 holes. The second one on the right is occupied. The other three can be installed at will. Prepare to install it in the first hole on the left.