Convert 120v to 12v for LEDs

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Joined 2011
That would work, but you could just use the amplifier power supply instead of the 12V supply,
with suitable (larger) resistors. Also you can use any LED color you want. Most do not want
real bright LEDs and use a larger resistor to drop the current.
 
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Joined 2002
Hi, I use the thermal pin like Yatsushiro mentions and it then has the "power on" LED function and when the device overheats the LED stops glowing. Since I never had an overheated ICEpower module I can only assume that it works :) This way is the easiest way to connect a "power on" LED to ICEpower modules. You will still need a series resistor so in effect just 2 parts!

NBPK402, please rethink the purpose of either a blue LED and then also the use of a super bright one. These are against or even over the pain limit for many people as the color is terrible and the brightness is extremely annoying and reminds one of cheap Chinese electronics. Its safe to say most even want to dim high brightness types as these light up a room easily with cold unpleasant light. I think a diffuse low brightness type is what you need. The modern blue LEDs glow with very low currents so you might need a high value resistor for the right brightness (you might want to try out first with a potentiometer). The machine code we use here says green to be for normal situations and red for error situations.

Recently I tried out 2 mm green LEDs for "power on" and these are subtle and still give enough light output to indicate the device is powered on. These can be mount more easy as well as drilling a 2 mm hole is easy and the body of the LED is larger so a little bit of glue at the back of the front cover is all that is needed. Till now I like these the most of all the LEDs I have used.
 

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It is simpler to connect a suitable 5v led to either the Over Current Pin (pin 3 on P102), or the Thermal Monitor Pin (Pin 4 on P102), or both, as these are both high in normal operation.

See the datasheet http://www.sound-power.ru/files/doc/ICEpower125ASX2_datasheet.pdf
When I do this 1 connection of the LED goes to pin 3...where does the other pin go to?


Would these work to run off of the suggested power source listed above on the Icepower amp? These are the same ones I have in the AmpCamp amps I purchased.

Super Bright Blue 5mm LED 3000 mcd 100 Piece Kit with Voltage Dropping Resistors
 
It isn't just the color that makes those less suitable as indicators -- they're very narrow beam light output will make them so bright as to be painful when viewed on axis, yet hard to see only 45° off axis. LEDs designed as indicators typically have much wider dispersal. These appear to be intended as light sources, not indicators. If you are determined to use them, at least try using some 220 or 320 wet-or-dry abrasive paper to rough up the nose; you could even try flattening it somewhat.

And be sure not to botch the polarity, even for an instant. Blue ones especially hate that.

Cheers
 
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It isn't just the color that makes those less suitable as indicators -- they're very narrow beam light output will make them so bright as to be painful when viewed on axis, yet hard to see only 45° off axis. LEDs designed as indicators typically have much wider dispersal. These appear to be intended as light sources, not indicators. If you are determined to use them, at least try using some 220 or 320 wet-or-dry abrasive paper to rough up the nose; you could even try flattening it somewhat.

And be sure not to botch the polarity, even for an instant. Blue ones especially hate that.

Cheers
These LEDs are the same ones used on my Pass Ampcamp monos, and the light is not bright at all...just a nice low light blue that lets you know it is on.
I am trying to use the same leds as AmpCamps as I want to use up some of my 100 pack of LEDs I bought due to 2 of my AmpCamps do not have the LEDs to match my 3rd AmpCamp amp and I will be using 3 Icepower amps in similar amp cases.
 
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You seem to persist in making things complicated and adding complexity where none is needed. :rolleyes:

In the link to the LEDs that you have, it states that they are supplied with suitable resistors for connection to a 5V or 12V supply.

Why not use your LED and resistor and connect to the 5V pins as explained above? :confused:

If you really must use the step down converter, just adjust it down to 3.2/3.4V and connect it directly to the LED, no resistor required.
 
Thank you for the info... what I want to do is have the power switch LED light up when it is pressed ( which controls 2 amp modules), and then have my LEDs (2 of them on the front panel) light up to acknowledge they in fact did power up. To do this I can use the 5v one for each amp module to each LED, and then use 1 of the amp modules 24v power to feed the power switch LED. Does this make more sense? The only other way I can think of is to have a 120v to 12v connect to the swirch and the other LEDs connect to the 5v.
 
You can connect multiple Leds if you wish to any available voltage source in those amps, with the proper limit/dropping resistor on each Led.

For me simplest is using the auxiliary 25V supply and a 2k2 resistor as MAAC0 suggests, a no brainer.

IF there are other 5V or 12V "intelligent" sources and you know how to use them as was explained above, go for them if you want; I´m a minimalist/simplifier and know 25V will be present when amp is ON, good enough for me

If you really must use the step down converter, just adjust it down to 3.2/3.4V and connect it directly to the LED, no resistor required.
Sorry but you always need the series resistor, LEDS are current driven.
Yes, they will also "drop "X" voltage" but you can´t trust that for adjustment.