spinning rainbow wheel

harrisonic

New Member

• Dec 7, 2011

• #1

HELP!!! somebody knows this circuit operates?

 

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Last edited: Dec 7, 2011

Ian Rogers

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• Dec 7, 2011

• #2

When the output of the 555 is high, the bottom transistor turns on two of the led's (supplies 0v).The middle one interrupts the current flow to the third.
when the output is low the bottom and the middle transistors are off so the third turns on the other three led's

 

harrisonic

New Member

• Dec 7, 2011

• #3

transistor connection

is this a darlington pair connection?
how its operates?

 

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Ian Rogers

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• Dec 7, 2011

• #4

I answered this in your other post... they are performing a NOT situation (inverting).

 

alec_t

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Most Helpful Member

• Dec 8, 2011

• #5

The pic doesn't show which are the emitters and which are the collectors of the transistors, so the function is indeterminate.

 

Last edited: Dec 8, 2011

Ian Rogers

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• Dec 8, 2011

• #6

Alec they are all npn's drawn the normal way round... I've put the circuit in ISIS the led's just flash in unison whilst spinning.