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Old November 27th 05, 01:06 PM posted to de.sci.electronics,rec.radio.amateur.homebrew,sci.electronics.components,sci.electronics.design
Martin
 
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Default Unusual functions of cheap parts

Am Sun, 27 Nov 2005 09:57:23 +0000 (UTC) schrieb Matthias Weingart
:

Martin wrote in
news
To save power, use the LEDs of a backlight to measure the ambient
light to decide to switch the backlight on or not.

But how to decide to switch it off? I think there you have to
sample - switch of for a short time and test. This could give a
flickering backlight.

Ok, you found the skeleton in the closet. :-) You can not use
this method to switch it off - but it is not required in most cases.
Think of a cell phone - the backlight goes on every time you press a
key, and it is going off after 10 seconds.


OK, so you can decide to not switch it on and save some mAs.

--
Martin