Omega2+ direct connect with relay expansion (small housing)
Patric Wilms last edited by
I want to solder the relay expansion directly to the omega2+ due to needing for a smaller casing.
My Plan is to use input USB 5v via the regulator to 3.3 so that the onion is powered. (https://docs.onion.io/omega2-docs/hardware-prep-no-dock.html)
I've found the schematics for the relay but I'm bit confused because I don't know which pins are only needed for the relay and which are unnecessary.
Which of the conedge pins are actually used because there is for example 3 times ground?
Here is my rough concept:
György Farkas last edited by György Farkas
@Patric-Wilms I think your concept is correct.
Most probably that the 5V pins 2 and 28, the 3.3V pins 3 and 30 and the GND pins 1 and 26 and 29 of the header are common / joint respectively on the Relay Expansion. You could check this with a multimeter / ohmmeter easily.
And please correct me if I'm wrong because I don't have such genuine Onion board.
Powering the Omega with No Dock has "the only procedure recommended by Onion" - but the input and output capacitors of LD117 3.3V voltage regulator are missing from that circuit - I don't know why (maybe intentionally ;-).