Application and circuit:
Powered from a 6 circuit fuse block that has both constant and switched power to the output terminals. Item powered is a dual USB 2.0 port, max forward current if both ports are used simultaneously with a device drawing max current is 1 amp @ 12VDC (supply voltage does very from 11.8 to 14.8VDC)
The USB port has two circuits feeding it so it can be powered and shut off with normal key on bike running (circuit 1) and powered with a switched second circuit when the bike is off.(Circuit 2)
The issue I have is, the fuse block is being energized by by circuit 2 The switch used for circuit 2 is limited to a SPST miniature push button switch that fits a specific mount.
I need to prevent current flow back to the fuse block when circuit 2 is used. I have been using two 1N4004 diode in parallel successfully. I understand some of why pairing diodes like this is not the correct solution.. So the question, what is the correct diode for this application? As said, an alternate switch is not an option, nor is altering the fuse block. So the solution needs to be something between the fuse bloc output terminal and the usb PORT