74C02 replacement - Quad NOR to 15V! 2

Welcome to the seedy gray market of electronics. You will have to deal with the guys wearing trench coats, driving grey primered vans, and meeting on secluded back roads to procure one. It will likely require you to buy all of whatever stock a grey market buyer has. So it becomes a visit to all the grey market places in search of the one with the least number of chips, in an attempt to keep the price down.

Just google for 74C02 and wade on in.

Keith Cress
Flamin Systems, Inc.-

Here's a start:


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Thanks, looks like i can get them after all... but if I can find a replacement I can save some huge $$ and headaches down the road.
Does anyone know of a modern replacement chip?

Mouser shows 74C02 offered by NTE (a line of replacement parts) in stock at around $33 each. (Ouch!) Newark shows the same NTE at around $25 with a 17 day leadtime. Digikey recoginzes the number, has no stock, and shows a minimum buy of 25,000 at around $7 each - I think that's the minimun $$ it takes to make a semi company run a few wafers.

4000 series CMOS are still around. You could re-spin your board to use a 4001B CMOS (quad NOR). They're still readly available and operate to 15 volts as well. Half the gates in the package match the pin-out of the 74C02. You would have to rewire 4 of the pins to work. Or, could you make an adapter board to use the 4001B? A CD4001B from TI, ON Semi, or Fairchild are available at Digikey for around $0.50 each. They're even available in several different SMT packages. There is probably a 4000 series schmitt NOR - you could search the 4000 series offerings more.

The 4000 series CMOS devices were the most popular of this kind of higher-voltage device. The 74Cxx equivalents of the popular 74xx series 5 volt logic never became as popular, so they're hard to get where the pinout differs from the 4000 series.

Thanks, it looks like the 4001 is the best choice for moving forward, and for the current design, I'm sure I can make an adapter board for less than $16.50!!!