View Full Version : CAn I coonect two LED's in parallel on LED64?

04-16-2005, 08:54 AM
Hi all. Just got the LED64 unit. I have two questions.

First question............

Is there any reason that I cannot connect two LEDs in parallel on a single "output"? The annunciators from Flight Deck Solutions are designed to have two LED's mounted in them. Of course for the indicvators that I might want to have a red and a green LED in it to show "state" .... that works great being driven by two circuits. But a single led, even a high intensity one ... sitting on one side .... will not illuminate the annunciator very evenly. I can accept this for the two color situation.

Second question.........

Can I drive something like a small reed relay off one of the outputs of the LED64? I want to be able to control something other than a LED when a certain state is "true".

Appreciate the help in advance.



Steve Daly
04-16-2005, 07:13 PM
I know nothing about this John...but you should be able to trigger a MOSFET transistor from the LED64 output stage...MOSFETs are what are used in electronic speed controls, you know they can handle a fair bit of current. :)

04-19-2005, 08:07 AM
Hi JBaymore,
I too have the LED 64 and with what your asking..I believe you can get away with paralling 2 leds on i output.
I myself have not tried it but I think it will work; except if 1 led goes out they both do.
As for how many leds you connect with this method?...I would not recmend it.
Try to keep 1 led per output preferred..sneek a 2nd led if you MUST ONLY.

As for driving a reed switch from this board...no; the reed switch works on a magnet passing past it pulling the tiny switch closed.

Kind regards


04-19-2005, 09:11 AM

Thanks for the info.

What I might do is try two leds to even out the light in the annunciator... but use lower light output ones.... that draw less current each... to keep the mils under control.

Also .... not a reed SWITCH... but a reed RELAY. A small low current primary relay that I can use to "switch" other higher load stuff. I know I can get the heavy duty relay Phidget card.... but for what I want that is serious overkill. Plus I want to have some double pole double throw type logic on some indicators.



04-19-2005, 12:08 PM
My mistake John..didnt see the key word "relay"

I havnt used one yet..so I cant say..but lead the way for us and let us know! :)


04-25-2005, 07:33 PM
The only problem with this is that LEDs will turn on at slightly different voltages. So one LED could fire up and consume all the current. If you put a small resistor in series with each led, and then parallel them, this will work fine. Try 50 Ohms for the resistors.

This will not work well for white/blue leds. For most red/green/yellow leds, there is enough voltage headroom that a resistor will not affect the brightness.