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I need to find a device I can use in place of the MC14495-P1 binary to hexadecimal LED driver. This part is sadly very scarce and very expensive these days.

The device is a 16 pin DIP with +5V on pin 16 and Gnd on pin 8 (standard logic chip arrangement)

The closest I have come so far is a 14 pin PIC16F and a bit of reworking of the PCB, but that's going to be a pain in the sphincter as I have to do about 80 of them.

So I am wondering if there is a programmable device from one of the other manufacturers, like Atmel, Maxim, TI, or whoever, that is 16 pins with the power laid out like I need and all the other pins available for IO? I haven't found one as yet, but if anyone has any suggestions I'd be very grateful.

Oh, and they have to cost < £1 each.

Majenko
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  • yikes, that is a weird pin out, not even close to the 74 series standard and looks like a pain the route as well. – Mark Jun 28 '11 at 03:59

3 Answers3

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You might be to put a small PIC on a daughter board with pins sticking down to emulate the 16 pin DIP footprint.

Olin Lathrop
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According to Octoparts XsMicro may be able to help you get the original.

Federico Russo
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  • I have had millions of quotes from Chinese companies quoting anything from $10 down to $0.20 - but do I really trust them...? Plus, delivery is a killer. – Majenko Jun 27 '11 at 09:54
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You also have a problem with the drive arrangement. The the device you used is designed to drive the LED segments directly (supply the current) and includes internal current limiting resistors.

You don't find many MCU that can directly drive LEDs like that (at least not so many) and I don't know of any with internal current limiting resistors.

Fairchild makes a similar part, but the pin out is different and much more "standard", i've never actually seen a 7-seg driver with a pin configuration like that Motorola part, I've seen some differences in the input side but all the segment outputs are always at least on one side of the IC. As such using any other driver i can think of would require PCB rework or an adapter board.

Even the PIC would still require additional external circuitry that likely isn't there for the current chip.

In theory a DIP-16 PLD is an option but they are getting harder to find (expensive), would require additional external circuitry (current limiting) and usually the programmers are quite expensive.

Unless you can find more of that Motorola chip I think your stuck creating an adapter board for something like the Fairchild IC listed above.

Mark
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