Hi
Iam looking for advice.
I want to translate and buffer 7 signals from mpu to outside world. What should I use to do it? It is one way only from 3.3 to 5v.
Can I just use something like 74AHC244 8bit Buffer/Line Driver 3 state? If yes what should I do with unused one? Just leave it floating?
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It helps build a picture where our "good traffic" is coming from..
Thanks :)
3.3v->5v 7 signals
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arkadiusz.makarenko
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3.3v->5v 7 signals
Do not trust people. They are capable of greatness.
~ Stanislaw Lem
~ Stanislaw Lem
Re: 3.3v->5v 7 signals
It depends exactly what your doing... as TTL inputs will accept 3.3V as a HI anyway...
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arkadiusz.makarenko
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Re: 3.3v->5v 7 signals
It is external signal which will be sent outside, maybe over the cables to external device. And I would like to protect mpu as well.exxos wrote: Tue Sep 29, 2020 5:14 pm It depends exactly what your doing... as TTL inputs will accept 3.3V as a HI anyway...
Do not trust people. They are capable of greatness.
~ Stanislaw Lem
~ Stanislaw Lem
Re: 3.3v->5v 7 signals
74AHCT244 or 74AHCT541 work well. You can also use 74HCT.
Just tie the unused input to ground or 3v3.
Just tie the unused input to ground or 3v3.
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arkadiusz.makarenko
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Re: 3.3v->5v 7 signals
Thank you.cmorley wrote: Tue Sep 29, 2020 6:39 pm 74AHCT244 or 74AHCT541 work well. You can also use 74HCT.
Just tie the unused input to ground or 3v3.
Lets see how it will work out.
Do not trust people. They are capable of greatness.
~ Stanislaw Lem
~ Stanislaw Lem
Re: 3.3v->5v 7 signals
Use a 74LVC244 with pull-up to 5V on the output (5V side).
It's a 3.3v device with 5V i/o support. I use it a lot of places exactly for this.
Rodolphe
It's a 3.3v device with 5V i/o support. I use it a lot of places exactly for this.
Rodolphe
Working ones : MegaSTE (68020) / TT030 / Falcon with AB040 & Eclipse / 1040STF
Need testing : Falcon with CT2
Need testing : Falcon with CT2
Re: 3.3v->5v 7 signals
I've been using 74AHCT245As for my VGA mod, since they only cost AUD 50c each and they do the job. If you only need a single-directional driver they work the same as the 244s (I just tie DIR to ground).