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How would I substitute the LM555 for the LM556 in this circuit? Answered

I'm trying to build a small amplifier with a timed soft start circuit. Now, I thought it would be better to make the whole thing smaller by using the LM556. I'm not good at actually mapping circuits and everything I've built was all someone else's design.

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jensenr30 (author)2011-02-21

go here for a schematic of a 556!
http://www.kpsec.freeuk.com/555timer.htm#bistable

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iceng (author)2011-02-03

I will draw u a schematic tomorrow.

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ARJOON (author)2011-02-01

https://www.instructables.com/answers/could-i-use-2-555-timers-instead-of-one-556/

already answered

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Quercus austrina (author)ARJOON2011-02-01

The question is actually the other way around, use a single 556 instead of two 555's.

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ARJOON (author)Quercus austrina2011-02-02

same thing use the conversion table

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Quercus austrina (author)2011-02-01

Look up the PDF for the LM555 and the LM556. The 556 has two 555's on one die with a common connection for +V and GND. All you have to do is map the pins from the 555 to the 556 and you'll be good to go. Easy peasy.

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user

+1

@Author

See in your drawing how the 2 555's have pin 1 and pin 8 identical to power and ground? Same thing here.

556 '1' and '8' (different pins, look up to be sure) go to power and ground, the rest hook up as if they were 2 separate chips. 234567a and 234567b act like 2 totally separate chips (With common power and ground). They will be NAMED instead of numbered, like 'drain a, drain b' etc.

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user

On the LM556 pdf, it says that pin 14 is Vcc (power) and pin 7 is GND. Pins 1-6 are for the 1st timer and pins 8-13 are for the 2nd timer. Seriously, all you have to do is match up the pins and you are good to go.

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