Switch and diode

[Nescafe]

Hi, can someone confirm that the schematic below will work safely?

Thank You.

 

[dougy83]

Your simple diode-OR configuration looks fine to me. I assume the diode forward voltage drop won't affect the triggering of the relay driver C and that there is a pulldown on the relay drivers already (or that they don't require a pull-down).

 

[Nescafe]

Thank You dougy83, the relay driver is ON Semi NUD3112 or NUD3105 and it have pull down R embedded, diode is 1N4004 and the drop voltage is low enough for driver VGS treshold. I'm worrying about current flow loop, maybe I'm paranoid

 

[dougy83]

I'm worrying about current flow loop

What (or where) is that?

 

[Nescafe]

What (or where) is that?

When both switch is on and one of the diode is not right (leakage current), do I need to worry about that?

 

[dougy83]

When both switches are on, there is no leakage current to worry about.

 

[Nescafe]

ahahaha......my bad, I mean when one switch is on....., do this circuit is safe as using "OR" logic gate?

 

[alec_t]

this circuit is safe as using "OR" logic gate?

The 'safety' is probably similar. A diode failing open or short circuit would result in false operation; but so would failure of a logic gate.

 

[eTech]

Hi, can someone confirm that the schematic below will work safely?

Thank You.

Hi

What do you mean by safely?

Is it going to control something that can potentially cause bodily harm if it fails?

eT

 

[Nescafe]

Hi,
this is for audio device, so no body will harm, and by safe I mean is the possibility for the diode to fail compare to the logic considering the diode will directly connect to VCC (big current).

 

[alec_t]

But the logic circuit also "will directly connect to VCC (big current)". I don't understand your concern.

 

[Nescafe]

Then the risk is the same whatever I use, so nevermind.
Thank You everybody.