Finally took the time to unsolder the pins of the DC step-up module to resolder them on the bottom side, it was not so straight-forward but with lot of flux and a solder braid, I could clean up the via enough to perform the modification
2023-10-28--01-dc5v-under-test.jpg
And thus I could do some testing, varying the current to be served. I could see the effect on the 5V rails, the voltage dropping with the increase of current. Depending on the load of the 12V rail, you will be more or less tight (we want to have at least 4.5V, more is better). About the 12V rail, the voltage were at a stable 11.98V. Here are some data points :
Capture d’écran du 2023-10-28 22-05-32.png
And the data as text :
Code: Select all
12V Load (A) = 0,24
==================
5V load (A) 5V Voltage (V) ΔI ΔV R (Ω)
2,9 4,36
2,5 4,51 0,4 0,149999999999999 0,374999999999999
2 4,687 0,5 0,177000000000001 0,354000000000001
1,8 4,758 0,2 0,0709999999999997 0,354999999999999
12V Load (A) = 0,36
==================
5V load (A) 5V Voltage (V) ΔI ΔV R (Ω)
2,9 4,25
2,1 4,525 0,8 0,275 0,34375
1,8 4,665 0,3 0,14 0,466666666666665
Anyway after that, I chilled a little with my test program :
2023-10-28--02-plug-and-play.jpg
I had to take care so that the wire of the power adapter is kept away from the video cable, otherwise some humming is to be expected.
So the next iteration :
- I don't want to modify the step-up module, I will change the orientation of the footprint for that.
- I also have to fix the footprint and position of the block terminals.