Published:2013/7/29 1:51:00 Author:lynne | Keyword: Up/Down Fading LED | From:SeekIC
These two circuits make a LED fade on and off. The first circuit charges a 100u and the transistor amplifies the current entering the 100u and delivers 100 times this value to the LED via the collector-emitter pins. The circuit needs 9v for operation since pin 2 of the 555 detects 2/3 Vcc before changing the state of the output so we only have a maximum of 5.5v via a 470R resistor to illuminate the LED.
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