The fuses are dual function.
Instead of selecting a jumper, with is hard to find that can handle 10 amps or 7.
I also want to be able to select what output voltage to have on each Chanel, so you are only suppose to put one fuse in, at once for each Chanel.
The benefits are that I also can have a fuse on each Chanel.
I was locked at the design of this relay card: https://www.electrokit.com/produkt/8x-relakort-seriellt-ek006/
It looks like it only have one diod to protection for all relays. I hade diodes in parallel with all relays but decided to use only one.
At the moment most diods on the pcb are in wrong direction. Only Chanel one on the output is corect. So most of them would create a short circuit.
For example look at the diods after the d-sub. They are corect in the schematics but not correct on the pcb.
I want the board to handel about 150W at 5 volt.
Let’s say 160W, = 32A at 5V
I also would prefer if each output could handel 7,5A per Chanel.
2.5*3=7.5A per Chanel.
So they don’t need to handel 10A per Chanel but it is good with head room.
All chanels should be able to handle 7.5A but all don’t have to do it at once.
But what I am most worried abut is the return current. I don’t have a clear ground path for return current. A lot of tracks in the way of the current on the ground plane.
The relays will be controlled 2 ways. Either with toggle switch or with external GIPO like arduino or Pokeys.
Those inputs need to be protected. That’s why I put the diods in line with the inputs near the d-sub.
