Let's Make Robots!

My first PCB

Hi guys,

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,




Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

lastversionnocomp3D lastversion3D

Single PIN linked

Hi OddBot,

Can't get the flickr photo's up here but the schematic can be found here (or in the other link posted above):


I have used single pins now so I can use a piece of wire to cross the other trace (marked with a dark line).


The 0ohm resistor sounds sexier then a piece of wire, I'll look at that. :)

Please post a schematic. For me at least, it will convert a birdsnest of dip traces into a coherent, logical, circuit design. Then I can help you more.

When you cross over another trace (assuming a single sided PCB) then you will need a link. Usually this is tinned copper wire although you can buy 0Ω resistors to neaten the apearance of your PCB.