[GUIDE] Build a 3.3v adapter without soldering

I am not responsible for any damage you may cause to the motherboard.

I don’t tested how this adapter works, because at the moment I don’t have a motherboard with a chip that needs 3.3v “separately”.

I have checked the output values of the converter and they are 3.3V and 0.35A with the ch341a connected to the USB port.


One 3.3v converter (you can buy HERE or HERE)
Two wires (in my case red for positive and brown for negative)
One needle or paper clip (0.6mm -0.7mm)

Shrink tube
Electrical tape.

3.3v converter details (I have used this type)

Attention: Don’t connect the ch341a programmer and the clip cable to the motherboard and USB port, until the whole process described below is finished.

Before starting it is better that you leave the converter ready for use.

1.Connect the converter to the USB port and press the power button.
2. Adjust the output value to 3.3v.
3. Press the power off button.
4. Disconnect the converter from the USB port.

Build the adapter:

1. Strip the wires.

2. Insert the wires through the shrink tube

3. Use the needle or paper clip to make two “rings”

4. Place the shrink tubing near the “rings” and use a heat source to shrink it.

5. Insert the “rings” on the pins 4 and 8.

6.Fasten the cables with electrical tape.

7. Cut or isolate the pin 8 (from the other side of the board).

8.Connect the ch314a clip adapter. (Attention: at this point the clip cable and the ch341a USB programmer are not connected to the motherboard)

9. On the 3.3v converter, connect the red wire to “OUT +” and the brown wire to “OUT -”

10. Connect the 3.3v converter to the USB port and press the power button.

11. Check the output voltage on the screen (you need 3.3v)

12. If all is well, you can now test the ch341a programmer with the 3.3v adapter.

Kind regards.

1 Like