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Chip Identification

I'm going through all these chips I got with a brad board on ebay, trying to find out what they all are. Instead of just listing the part numbers of the ones I can find, let me as some general questions about the numbering conventions and then maybe I can find them myself. I have been looking the numbers up on digchip.com. Most of them are of the format SN74LS... Can someone tell me what the SN and the LS indicate? Then some don't have the LS.... so far I have found all of the ones that start like that But there are some that start MH74, M74, or DV74, and I can't find those numbers. Then there are some that are simply 7475, are those the same thing as a SN7475? Some have a suffix of P or PC and I can't find any of the SN74LS.... numbers that have a P or PC suffix on digchip.com. I will list 2 part numbers that I can't find and are very strange. MHB2114, UYC7483, and uPB74LS11C. On that last one the u is the Greek letter used as the micro prefix.

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Chris W
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Reply to
Chris W
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The *74* chips are TTL or TTL-ish logic.

The letter prefix indicates the manufacturer - SN is Texas Instruments. The letter suffix indicates the package - the package codes vary between makes.

Any letters in the middle (like "LS") indicate some variations in the internal circuits.

In general, if all the numbers are the same, the parts have the same logic function.

No middle letters = original fairly power-hungry version. Some parts in this series are still available, I think.

L = low power, slow (and obsolete)

LS = Low Power Schottky. Low power, but similar speed to the original.

ALS = Advanced LS

C = C in the middle letters indicates CMOS - very low power. (and just "C" is fairly slow)

HC, AC = faster CMOS parts

HCT, ACT = CMOS parts with the inputs modified to work reliably with bipolar TTL.

To find data on these parts, check Texas Instruments, Fairchild or On Semi's websites, or do a google for +datasheet.

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Peter Bennett VE7CEI 
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Reply to
Peter Bennett

Those are 74 series TTL logic (except for 2114 which is a 1024 x 4bit static RAM). LS indicates Low power Schottky. The prefixes indicate manufacturer. The suffixes indicate package.

Try searching for the chip numbers on Google. You'll find datasheets. Try searching with .pdf on the end of the chip number.

Reply to
Andrew Holme

I recall SN as the Texas Instruments prefix Rich...

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Motorolla had their 'Batwing' M

Then there's the suffix: N for plastic (really epoxy) J for cerdip (both halves were ceramic surrounding the lead frame) P for ceramic (hermetically sealed types)

One could really wear off the finger tip skin by handling too many J parts!

Reply to
Lord Garth

The SN is a TI device. The 74 stands for commercial temperature range (for this series) and the LS is Low power - Schottky

This page provides part number prefix to manufacturer, the SN:

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This page defines the 'LS' protion

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This page defines temp range

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Hope this helps.

Reply to
Interfacebus.com

or

Do you recall TI's multivoltage (probably PMOS) UV EPROM, the TMS 2716? TMS stood for Too Many Supplies rather than Texas (Instruments) Memory Systems.

Reply to
Lord Garth

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