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FrozenGate by Avery

NOO!!






I'm beginning to think this capacitor that pervades many driver designs does more harm than good.
 
The output capacitor causes problems because it will charge up if the diode is disconnected for any reason, then if the cap is not discharged before hooking up the diode again, the cap will overcurrent the diode, killing it.
The fix is simple. Put a resistor (I use 470 ohm 1/4 watt) across the cap, so the cap is discharged whenever power is turned off. No more forgetting to discharge the cap when installing a diode. Works for me.
 
wow... sounds like a good fix if thats how it works. I wonder how that affects the circuit in terms of how it affects the amount of current going out. Since that hookup would be parallel, I would think that that will affect the current, but I don't know by how much (too lazy to do the math).
 
i think its best to solder cap directly to diode thats how i did it cause that way he can't be charged without diode and wont kill it
 
I have to say, I'm liking this thread. It's helping me learn so new tips which are useful. Soldering the cap directly to the diode sounds like a good idea, I'll do that next time for sure. Also, I was wondering, what can I do to prevent the diodes from being harmed by ESD? I have a feeling my last two diodes died either from ESD or from putting resin epoxy on the leads after soldering to them.
 
Puting epoxy on the leads should not be a problem, ESD could.

Get or make an earthing strap which you can clip onto the chassis at the rear of your computer.

Regards rog8811
 

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Alexizupinhea said:
I have to say, I'm liking this thread. It's helping me learn so new tips which are useful. Soldering the cap directly to the diode sounds like a good idea, I'll do that next time for sure. Also, I was wondering, what can I do to prevent the diodes from being harmed by ESD? I have a feeling my last two diodes died either from ESD or from putting resin epoxy on the leads after soldering to them.
Click to expand...


ALWAYS wear an anti-static wrist band when working building lasers. I usually keep mine on from the moment I sit down to start taking out the components until I close up the host. It probably isn't needed after the driver is attached to the diode, but why take the chance? It doesn't cost me by the minute ;)

I also store all of my components in anti-static packaging.

Peace,
dave

@ DayOfShadows -- It may have only been "mostly dead" ;) (points for the source)
It seems to be full of life again.
 
Yea... then I have a feeling I broke all my diodes because of ESD. I'll be much more careful from now on. I might buy some more PHR-803t diodes now from Jake who is selling for $11.50 again (I didn't realize he was selling before for $11.50 so I bought from Blu-Ray for $13). Anyway, Is there an easy way to make sure my circuit components are protected from ESD? Like, I already built a DDL circuit, so could I just touch all the leads together on a big piece of metal, then it'll be ok? Sorry for all the questions, but I never knew much about ESD untill now. I guess I'll read wiki a little.
 
daguin said:
@ DayOfShadows -- It may have only been "mostly dead" ;)  (points for the source)
It seems to be full of life again.
Click to expand...
Ok ill delete my post saying thread closed if i have too :P :) ;)
 
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