74LS244 Alternative pinout ?

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exxos
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74LS244 Alternative pinout ?

Post by exxos »

For example, there is a alternative pin out to for the 74LS373, which is the 573.. where the 573 as inputs all down the left side and outputs all down the right side.

The 244 as input and outputs down each side which makes difficult routing, but so far I have been unable to find a bus transceiver which has all the inputs down one side... Anyone never seen such a alternative?
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Re: 74LS244 Alternative pinout ?

Post by JezC »

@exxos Maybe a 74LS541 is worth looking at?

Might not give you the individual enables on the different nibbles...
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Re: 74LS244 Alternative pinout ?

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JezC wrote: Mon Aug 10, 2020 11:42 am @exxos Maybe a 74LS541 is worth looking at?
Ahh! I was sure there was a chip like that but could not for the life of me find it, :thanksyellow:
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
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Re: 74LS244 Alternative pinout ?

Post by JezC »

@exxos No problem...glad to help!

At least some of the memory is still working...30+ years after last using these devices.
Numbering is strange though, you'd expect it to be a flow-through 241 rather than a 244. :shrug:
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Re: 74LS244 Alternative pinout ?

Post by exxos »

JezC wrote: Mon Aug 10, 2020 11:48 am Numbering is strange though, you'd expect it to be a flow-through 241 rather than a 244. :shrug:
I thought that as well :roll:

So using some sensible layout chips the routing has improved dramatically...

Capture.JPG
Capture.JPG (107.2 KiB) Viewed 3225 times

There was just that many things crossing over all over the place it was just madness :pullhair: :stars: :crazy: :headbang:
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Re: 74LS244 Alternative pinout ?

Post by JezC »

@exxos Yup, know that feeling well.

It was so bad at one point that we were using wire-wrap for prototypes as it saved waiting for multi-layer PCBs to be made.
Worked ok for low speed or simple designs but needed true power and ground planes for bigger/faster clock rates.

One of many reasons why I moved over to writing s/w instead...plus the outside chance to preserve any remaining sanity.
:lol: :roll:
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