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So I have the footprint for a 2-input Quad AND gate (SN74LV08A) on a PCB. It is a 14-TSSOP and is pinned out like this:

enter image description here

However, I want to change the logic to four NOR gates. The problem is, all of the NOR gates seemed to be pinned out like below:

enter image description here

Is there a database for this kind of thing or is going to digikey or mouser and playing the guess and check game my only option?

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  • \$\begingroup\$ You want to covert 2 Quad AND into 2 Quad NOR?or you confused because of pinout? \$\endgroup\$
    – MaMba
    Commented Jul 30, 2015 at 13:20
  • \$\begingroup\$ I want a quad nor gate with the pinout shown on top. \$\endgroup\$
    – ACD
    Commented Jul 30, 2015 at 13:22
  • \$\begingroup\$ I have seen these PINOUT mostly isc.dcc.ttu.ee/Public/Kuphaldt/exper/05298.png and makeyourownchip.tripod.com/7402diagram.gif ,don't really know if there is a documentation about rather I would also like to know about it. \$\endgroup\$
    – MaMba
    Commented Jul 30, 2015 at 13:26
  • \$\begingroup\$ If you don't find what you are looking for, a potential workaround might be to turn the chip around and swap the Vcc and GND pins. \$\endgroup\$
    – Tut
    Commented Jul 30, 2015 at 13:42
  • \$\begingroup\$ Makes you wonder why the 7402 had a different pinout from the 7400, 7408 and 7432. What were they smoking? (Rhetorical question, the chip came out in the late 1960's. We know what they were smoking.) \$\endgroup\$
    – tcrosley
    Commented Jul 30, 2015 at 17:39

1 Answer 1

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I doubt any such database exists (finding it and searching it sounds like a lot of work), but if you (skillfully) do a parametric search, there are very few families to search in so it only takes a couple minutes to scan the few pages of part numbers.

The 74xx02 series is not what you want

The 4001 series is not what you want

The (ancient and probably unavailable in TSSOP) 74XX33 is not what you want

The 74HCT7002 looks like what you want if you don't mind ST inputs, HCT family.

enter image description here

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    \$\begingroup\$ That or the SN74HC36 - but it would take a stroke of luck to find one of them. \$\endgroup\$
    – Tom Carpenter
    Commented Jul 30, 2015 at 13:51
  • \$\begingroup\$ What is ST inputs? Schmitt triggered I'm assuming. I also found this chip via the guess and check method. Just curious how did you come across this? \$\endgroup\$
    – ACD
    Commented Jul 30, 2015 at 14:40
  • \$\begingroup\$ I just filtered the results until only four classifications remained, so I only had to look at a couple datasheets. I left the package unfiltered even though it took a bit longer because I didn't want to filter out something that might be rare, but still available somewhere. Yes, Schmitt trigger. \$\endgroup\$
    – Spehro 'speff' Pefhany
    Commented Jul 30, 2015 at 15:20
  • \$\begingroup\$ @SpehroPefhany What classifications? I filtered by package, num of inputs, num of gates, gate function and had over 200 results on digikey. \$\endgroup\$
    – ACD
    Commented Jul 30, 2015 at 19:48
  • \$\begingroup\$ 'In stock', eliminate 'tape and reel' & 'digireel', gets down to 1 page of 50- and there are just three classifications left- mostly 74xx02, but also 4001 and 7002. I wouldn't bet on this part being available in 10 years, BTW. \$\endgroup\$
    – Spehro 'speff' Pefhany
    Commented Jul 30, 2015 at 20:09

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