My first PCB
March 6, 2012
I started on some unfinished projects again but I could use some advice. I'm trying to build a board for the mini reef that can switch 6 devices (solenoid valves) at 12v DC with the PIC/Prop controller. I'm using diptrace for this as this seems to be the favorite choice. So far I love it.
I came up with the below but I'm running into some problems with the traces. Maybe someone can point out the right direction as I think that it must be possible to cross over a line (with some electonic component maybe)? The red circles are the problem areas.
In addition, I'm probably making mistakes since this is my one of my first pcb drawings: Please tell me if I got something wrong. It basically does (or is supposed to do) this: 12v DC goes in, 5v DC goes in, the PIC controls the relay coil at 5v, 6 channels, 6 times 12v switchable (on/off) output. Each relay can handle 1 amp, the fuse is 6 amps. I used oddbot's "regulated power supply" with the 470uF and the 0.10uF capacitors to prevent peaks on any channel. Since it will go on and off frequently i just guessed this was a good plan. For switching the coils I used the 2N2222A transistor with the 1N4148 diode schematic. This kind of sucks as I wanted to run it of 12v all together (and just use the PIC to deliver the 5 volts, but thats a bad idea I read down here). Dropping the voltage and turning the board into a watercooker doesn't attract me so I'm going for an extra powersource (prob some rechargeable cells and maybe a solarcell to keep it full). Maybe I could even use the 12V battery to charge the 5v (4.8v) ones. The latter seems more efficient then using a voltage regulator.
Thanks for the advice!
All the best,