HDD Access LED..voltage/current.

thegoonden · 13 Mar 2011 at 11:11

Any idea what the output on your average HDD access light pinnout on a motherboard is?
I can't see my access LED from my workspace and am toying with the idea of attaching a small 7 LED bar to it so the whole case internals flash in time.....but suspect it may cook something.
Any thoughts on this or another way to do it?

Tealc · 13 Mar 2011 at 11:23

As far as I know the voltage is around 3.3v but as for amperage I have no idea. It might well be limited current and trying to wire up 7 LEDs to it could cause an issue with your motherboard.

Just to be on the safe side I would use a transistor to switch on the LED array when the HDD LED switch is closed.

I've never done this, nor do I intend to but a similar project was discussed recently on bit-tech http://forums.bit-tech.net/showthread.php?t=204758

thegoonden · 13 Mar 2011 at 13:53

Thanks very much indeed. I suspected a transistor would be required but wasn't sure...that link should sort me out.

AtaRo · 13 Mar 2011 at 14:10

Would it not be easier to just connect the LEDs to the psu molex connector.
Typical forward voltage rating for an LED is around 3.3v so you can safely wire 4 LED in series and connect it to the 12v molex and you can connect as many as you want.

edit: sorry i misread your post you want your case flashing together with the hdd access led in this case you need a transistor to do this.