Front Panel LED Voltage/Current Requirements

[AbydosOne]

I did a cursory search for something similar to my question and didn't find anything definitive, so here goes...

 

What are the voltage/current characteristics for standard front panel LEDs? (like the ones connected to the PWR and HDD pins on the motherboard)

 

I've wanted to replace the blue/red LEDs in my front panel with warm white ones basically since I got it. The existing ones look like standard 3mm LEDs without any current limiting resistors in-line. I've been slowly accumulating project parts and now I think I have everything I need (LEDs, soldering iron, solder, heat shrink, hot air gun, etc.) and so all that's left is to do it, but I don't want to kill anything in the process.

 

My presumption is that the LED headers are current controlled outputs, but what current are they? Does the diode junction voltage matter at all?

 

Thanks!

[thrasher_565]

5 hours ago, AbydosOne said:

I did a cursory search for something similar to my question and didn't find anything definitive, so here goes...

 

What are the voltage/current characteristics for standard front panel LEDs? (like the ones connected to the PWR and HDD pins on the motherboard)

 

I've wanted to replace the blue/red LEDs in my front panel with warm white ones basically since I got it. The existing ones look like standard 3mm LEDs without any current limiting resistors in-line. I've been slowly accumulating project parts and now I think I have everything I need (LEDs, soldering iron, solder, heat shrink, hot air gun, etc.) and so all that's left is to do it, but I don't want to kill anything in the process.

 

My presumption is that the LED headers are current controlled outputs, but what current are they? Does the diode junction voltage matter at all?

 

Thanks!

my guess in the manual would tell you thow voltages but if not some one els will tell ya. i think it low but you can get power els were if thats the case but depanetd on what led you use and what voltage it needs. good old mod.

Edited March 21, 2021 by thrasher_565

[W-L]

On 3/20/2021 at 4:47 PM, AbydosOne said:

I did a cursory search for something similar to my question and didn't find anything definitive, so here goes...

 

What are the voltage/current characteristics for standard front panel LEDs? (like the ones connected to the PWR and HDD pins on the motherboard)

 

I've wanted to replace the blue/red LEDs in my front panel with warm white ones basically since I got it. The existing ones look like standard 3mm LEDs without any current limiting resistors in-line. I've been slowly accumulating project parts and now I think I have everything I need (LEDs, soldering iron, solder, heat shrink, hot air gun, etc.) and so all that's left is to do it, but I don't want to kill anything in the process.

 

My presumption is that the LED headers are current controlled outputs, but what current are they? Does the diode junction voltage matter at all?

 

Thanks!

Usually they are already current limited by the output pins so there isn't a need for adding inline resistors. Only time that is really needed is if you use red or <3.0V forward voltage LED's which may burn out fast if you don't add a resistor. 

 

Going from blue to warm white isn't a problem I'd check the cables for the red one to see if there are any resistors inline.  

[AbydosOne]

On 3/25/2021 at 8:51 AM, W-L said:

Usually they are already current limited by the output pins so there isn't a need for adding inline resistors. Only time that is really needed is if you use red or <3.0V forward voltage LED's which may burn out fast if you don't add a resistor. 

 

Going from blue to warm white isn't a problem I'd check the cables for the red one to see if there are any resistors inline.  

Well, reporting mission success!

 

There weren't any resistors inline with the original LEDs, so new warm white LEDs were soldered at the end of the existing leads, LEDs tested, and then everything was buttoned up (but not before fixing some USB 2.0 headers that were bugging me while I was at it; internal Bluetooth now!). Set the motherboard RGB to match the warm white and away I went.

[thrasher_565]

32 minutes ago, AbydosOne said:

Well, reporting mission success!

 

There weren't any resistors inline with the original LEDs, so new warm white LEDs were soldered at the end of the existing leads, LEDs tested, and then everything was buttoned up (but not before fixing some USB 2.0 headers that were bugging me while I was at it; internal Bluetooth now!). Set the motherboard RGB to match the warm white and away I went.

nice