Input selector with DPDT relay: Is my wiring ok?

[Monrin]

Try something like this arrangement. The ground line(s) can go up the middle.

Thanks for these suggestions, rayma! I already started a new layout basing on it. Playing around a bit, I bumped into a general question.

Part of the reason why my first layout turned out a bit chaotic was that I kept the power part, and the signal part of the schematic completely apart in a way that power, and signal traces never cross each other. With a more logic layout that seems kind of impossible.

So now I'm wondering how important this approach really is? Is it okay if power, and signal traces cross each other, or should that be avoided?

look at adding a current saver circuit to reduce the operating current after the relay has successfully triggered.

AndrewT, thanks for your suggestions. The idea of a current saver circuit sounds interesting.

I googled the term but didn't really find a helpful answer till now. Could you briefly explain what is meant by it?

 

[rayma]

only

I kept the power part, and the signal part of the schematic completely apart
in a way that power, and signal traces never cross each other. Is it okay if power,
and signal traces cross each other, or should that be avoided?

That's a big subject. Even with only DC on the pcb there can be issues.
If you still need to have a power supply on the pcb, place it below
the first layout so the pcb is longer vertically. Keep the power input
to the pcb as far from the audio circuits as possible.

 

[lgreen]

Hi, I did one of these with momentary pushbuttons, works great.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

http://www.parttimeprojects.com/audio/diy/BOSOZwebpage.php

The dual coil latching relay will maintain its state across power cycles. My 5V relays work from below 4V to 5V, I drive them with 5.7 volts which passes always through a diode, so figure 5V in practice. I have no switching noise at all even though I made no provision for this. I am not sure I would want to drive the relay constantly in the on or off position. But I don't know a lot about relays....do check the relay coil resistance- may draw more current than you think. I put a diode in reverse across the coils as they can release voltage when they are released, ... I think.

 

[AndrewT]

.............. The idea of a current saver circuit sounds interesting.

I googled the term but didn't really find a helpful answer till now. Could you briefly explain what is meant by it?

post1027

http://www.diyaudio.com/forums/soli...-century-protection-board-52.html#post4517239
note the disagreement later on Vbe sat and how to avoid high dissipation in the switching transistor.

The switcher should be operated as "saturated", i.e Ib~10% of Ie