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Topic: 74HC595 and TPIC6B595 (Read 316 times) previous topic - next topic

idrisdraig

I'm trying to compare the pinouts of 74HC595 and TPIC6B595 from their datasheets.
Please can someone confirm whether I have the following pins matched correctly?
(Sorry I couldn't find a way to make the table more readable.)

Pin   74HC595 Pin   TPIC6B597
9 Q7' Output serial data 18 SEROUT Serial data output
10 MR Master reset 8 SRCLR Shift Register Clear
11 SHCP Shift reg clock input 13 SRCK Shift Register Clock
12 STCP Storage reg clock input 12 RCK Register clock
14 DS Serial data in 3 SERIN Serial data input
   

gilshultz

They look correct if you copied the nomenclature from the data sheet. The 595 is a bit confusing but you got it.
This response is to help you get started in solving your problem, not solve it for you.
Good Luck & Have Fun!
Gil

6v6gt

Did you use the same manufacturer's data sheet for both devices? TI refers to pin 9 of the sn74hc595 as QH' , at least in the one I found.
And you had no problem with the /G or /OE (output enable) ?

idrisdraig

The nomenclature was copied from what I believe were the manufacturers data sheets. (There was a glaring typo on one though!)

Should i be concerned by G and OE? (Im not sure whether im meant to feel ignorant.) They were both listed as the respective output enables..

I had understood that Qa-Qh were equivalent to Q0-Q7 respectively, so Q7' and Qh'  so should be the same? No?

6v6gt

It is just that I've just been through this myself recently when considering both chips for a project.
Different manufacturers add to the confusion with their own names for the pins of standard specification devices. Another name you sometimes see is strobe (meaning register clock and other similar terms). I just mentioned output enable (/OE /G etc.) because it is another name with multiple variants and you can't just leave it floating.

I also discovered an error during this exercise on the TPIC6B595 datasheet which I reported to TI. There is a mismatch between the pinout diagram and a the pin table for the pin labeled SRCK.


idrisdraig

It is just that I've just been through this myself recently when considering both chips for a project.
Was there any reason you didn't want to share your conclusions?  :D ;D :smiley-mr-green: :smiley-lol: :smiley-grin:  :-X

I also discovered an error during this exercise on the TPIC6B595 datasheet which I reported to TI. There is a mismatch between the pinout diagram and a the pin table for the pin labeled SRCK.
I spotted that too: pin 15 apears twice in the table and no pin 13.

6v6gt

Was there any reason you didn't want to share your conclusions?  :D ;D :smiley-mr-green: :smiley-lol: :smiley-grin:  :-X
. . .
I have no problem sharing the conclusion,  but it was for a very specific project which, incidentally, is here: https://forum.arduino.cc/index.php?topic=668279.0 where the issue was possibly saving two high voltage transistors to drive neon lamps by relying on the clamp diodes in the TPIC6B959, so the conclusion is probably not generally useful. Anyway, if you look at the description, you'll see what I did.

idrisdraig

#7
Mar 17, 2020, 12:08 am Last Edit: Mar 17, 2020, 12:29 am by idrisdraig
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