Input: 3~30 volts Output: 1.25~30 volts
- You need:
- 2 Buck converters
- Potentiometer
- Voltmeter

You NEVER use cheap Chinese single buck converter alone!
It will fry your Arduino or Raspberry or whatever you are connected to.
The original design of this module is great.
However, the Chinese version this one, the fake chipset will generate too much heat, as the heat goes up the output voltage goes up too and eventually it will fry your circuit.
But don’t worry if you have already bought these from Amazon or Ali-express, there is a solution by using cascade voltage down method.
Cascade Voltage Down Method by using 2 cheap buck converters

Right buck converter 1st input (Original potentiometer used)
Let’s say you have a good old 3A, 19volt output notebook adapter that you want to use to power your Raspberry Pi’s 2nd power supply (5v) because you have too many sensors.
(You don’t want to see all the parts separated hanging with the wires, so I stick all the parts together)
19v to 12v to 5v
First you adjust 1st buck converter (right) down to around 12v and then finally adjust 2nd buck converter to whatever the voltage you need.
This method it will generate normal heat and it will supply stable voltage & ampere to your circuit.

(Note about voltmeter: If you want to use under 3 volt output, you connect the voltmeter’s black & red wire to 1st buck converter’s input/output and the white wire to 2nd buck converter’s positive output, the black & red wire are to support voltmeter’s own power, and the white wire is to measure the voltage)
