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**Unlinozistimi** · 09-11-2007, 04:46 AM

Trying to build a DIY Wii sensor bar and want to plug 10 IR LEDs in parallel circuits and connect it to a powered USB port.

The IR LED power requirements:
Power dissipation: 100mW
Forward current: 100mA
Reverse voltage: 5V

USB port provides:
5v
100mA

It's been ages since I did anything electrical and just want to make sure it will work and I am not forgetting something.

**M1zdL0hh** · 09-11-2007, 04:57 AM

My assumption here is that you're going to have a power resistor in series (or one normal resistor per LED) to limit the current and drop the voltage to a usable level (5V is too much). 100mA may be the peak continuous forward current but you're probably going to want to run your LEDs at 20-30mA. In this case, 10 of them will draw 300-odd mA, which your USB port should be able to supply.

**Unlinozistimi** · 09-11-2007, 05:27 AM

Thnx. [thumbup]

09-11-2007, 04:46 AM	#1
Unlinozistimi Join Date Oct 2005 Posts 414 Senior Member	Quick Electronics Question Trying to build a DIY Wii sensor bar and want to plug 10 IR LEDs in parallel circuits and connect it to a powered USB port. The IR LED power requirements: Power dissipation: 100mW Forward current: 100mA Reverse voltage: 5V USB port provides: 5v 100mA It's been ages since I did anything electrical and just want to make sure it will work and I am not forgetting something. Share Share this post on Digg Del.icio.us Technorati Twitter
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09-11-2007, 04:57 AM	#2
M1zdL0hh Join Date Oct 2005 Posts 374 Senior Member	My assumption here is that you're going to have a power resistor in series (or one normal resistor per LED) to limit the current and drop the voltage to a usable level (5V is too much). 100mA may be the peak continuous forward current but you're probably going to want to run your LEDs at 20-30mA. In this case, 10 of them will draw 300-odd mA, which your USB port should be able to supply. Share Share this post on Digg Del.icio.us Technorati Twitter
	Quote

09-11-2007, 05:27 AM	#3
Unlinozistimi Join Date Oct 2005 Posts 414 Senior Member	Thnx. [thumbup] Share Share this post on Digg Del.icio.us Technorati Twitter
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