[sdiy] LED driver cable length

[Tom Wiltshire]

Fair enough. It seemed a bit much, but you've convinced me.

Thanks,
Tom

On 12 Sep 2011, at 21:44, Barry Klein wrote:

> Seriously.  I'm commenting from experience.
> First, handling them killed them by me and the factory.  Anything above 10V
> can kill them - that includes ESD from getting up from your non-ESD padded
> chair.
> CMOS has ESD protection, LED's don't.  9V is within the CMOS 4000 series
> input tolerance.  ESD is not.
> You want more?  Try measuring the EMP pulse on the long wire when lightning
> hits nearby...
> 
> Barry
> 
> 
> 
> 
> -----Original Message-----
> From: Tom Wiltshire [mailto:tom at electricdruid.net] 
> Sent: Monday, September 12, 2011 1:31 PM
> To: Barry Klein
> Cc: synth-diy DIY
> Subject: Re: [sdiy] LED driver cable length
> 
> 
> On 12 Sep 2011, at 19:49, Barry Klein wrote:
> 
>> You could get a transient inductive pulse through the cable upon 
>> connect/disconnect that could overvoltage the LED.
> 
> Seriously?
> 
> Isn't this one of those "you could"s that is really a "..but you *could* win
> the lottery"?
> 
>> Also ESD is something to worry about - especially if using white/blue
> leds.
> 
> Again, ESD blowing up LEDs? I've never even managed to blow up a CMOS 4000
> series using ESD. And I did try, although I don't wear many artificial
> fabrics. A 9V battery was required, and even then I had to do it wrong. Now
> *that* works for LEDs too.
> 
> I'm not really trying to knock what is probably technically correct advice,
> but it just sounds all rather over the top for what is just an LED at the
> end of a long wire. It's not like we're running a life-support machine off
> this jack lead. The worst case is the synth player has to wave his hand in
> time in the unlikely situation that the LED boxes die.
> 
> T.
>