For a number of DIY Projects for me the suitable power sources have been missing .
I solved this problem with the self-made multi-module .
It provides the continuous control of voltage via USB or 9V.
Step 1: Schematic and Bill of Materials
Are required :
9V battery clip
USB TTL module
Step Down Module
Simply solder everything together according to wiring diagram , except the USB TTL module . It can be connected via female jumper cable .
Step 2: Finish
After a few minutes you will have a beautiful , lasting working multi module with which you can infinitely adjust the USB or 9V battery power. Perfect for small test applications and the like.
A german version of this instructable can be found here / Eine deutsche Version der Anleitung finden Sie hier: