I'm looking to make up some "idiot proof" test devices for testing plug packs.
What I had in mind was a single LED for Postive voltages & also a single LED for negative voltages. You just plug the plug pack in & get an immediate indication as to the polarity. AC would light both LEDS.
The trouble is that I would like to make it as wide a voltage range as possible - from 1.2 or 1.5 volts up as high as I can.
Some plug packs are as high as 24 & occasionally 30 volts so idiot proof would require as high a voltage as possible.
The combination of LOW voltage operation & HIGH voltage operation seems to be the real kicker. I don't care if I have to use ICs or discretes just want to make something that will work. I took a look at various LED drivers & regulators but there are just so many of them that it is hard to find a suitable part.
A device sold supposedly to do this with a voltage range of 1.5 - 12 volts just had 2 LEDs & 2 resistors apart from the sockets!!!
I look forward to any suggestions.
Thanks,
Brian.
What I had in mind was a single LED for Postive voltages & also a single LED for negative voltages. You just plug the plug pack in & get an immediate indication as to the polarity. AC would light both LEDS.
The trouble is that I would like to make it as wide a voltage range as possible - from 1.2 or 1.5 volts up as high as I can.
Some plug packs are as high as 24 & occasionally 30 volts so idiot proof would require as high a voltage as possible.
The combination of LOW voltage operation & HIGH voltage operation seems to be the real kicker. I don't care if I have to use ICs or discretes just want to make something that will work. I took a look at various LED drivers & regulators but there are just so many of them that it is hard to find a suitable part.
A device sold supposedly to do this with a voltage range of 1.5 - 12 volts just had 2 LEDs & 2 resistors apart from the sockets!!!
I look forward to any suggestions.
Thanks,
Brian.