Found an article in an Elektor Mag...
Replacing your computer's case leds with their ultra-bright counter-parts can be hazardous to your mobo's health. Sure they work, and they look bright and twinkly, but they're like . Rather use the following circuit to drive them :
+ R1
-----/\/\/\/\------- ----------
| E / \ BC557 as seen from
- 4k7 B --------- | C B E | bottom, flat side
-----/\/\/\/\---| BC557 | ------------ facing down
| ----------
| | C
| --- +
| \ / LED
| --- -
| |
------------------
Ya... hate ascii cct's too. Don't wanna look for image server now...
R1 is determined by the LED you use. For 10mA ones (usually Blue) use R1 = 75 ohms, and for 20mA ones (usually Red) use R1 = 150 ohms.
(Be careful with your cct, check that no positive line touches a ground line or the side of the case somewhere...)
Update : Ok... so it looks like the ASCII thing sucks... I'll try an look from an image host... I'm freezing my bottom off...
Replacing case leds
-
GrimStoner
- Registered User
- Posts: 716
- Joined: 08 Oct 2004, 02:00
- Contact:
Replacing case leds
Last edited by GrimStoner on 23 Apr 2005, 02:33, edited 1 time in total.
