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In this case I am using 4538 retriggerable mono-multivibrators, i have bought them from all over and i have HEF14538 CD14538 MC14538's

Is this representing the different internal technologies used in the chips? Does this make ANY difference for standard use? Can I work of one datasheet for all of them!

They also end in BP BC and BCP in that order. Does this indicate the tolerance like in BC range transistors or the package type or something?

If anyone has a comprehensive "how to read components guide" or rule-of-thumb syntax I would appreciate a link as similar occurs with capacitors, transistors and other ICs.

Oliver Kellow
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In 4000-series it primarily indicates the manufacturer as Andy says : though I thought CD4xxx was originally RCA, then adopted by (some) other manufacturers.

This is in contrast to 74-series where the later letters in the prefix (74S, 74LS, 74F, and later 74HC or 74HCT etc) indicated mainly technological differences. (though 74F was originally proprietary to Fairchild it also meant Fast indicating a non-standard process)

So you can usually accomplish the logical aspects of the design from a single datasheet.

However - and especially with a monostable - the analog aspects are likely to vary between manufacturers. Maximum and minimum supply voltages, leakage currents, speed are likely to differ; so for example. if you are using unusually high resistances for unusually long delays, using the correct datasheet is essential.

I remember the HEF4000 series as significantly different in speed and supply voltage ranges, so possibly deserve to be treated as a different logic family, as do the crossover 74HC[T]4xxx with TTL-compatible supply voltages and speeds. However the logical design and pinout are generally the same, so within mutually acceptable voltage and speed ranges, they would normally be interchangeable. (Need to dig out some old databooks to crosscheck this, so don't take it as definitive)

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Can I work of one datasheet for all of them!

On this occasion I'd look at all three data sheets just for a few minutes so that you do understand the letters BP, BC and BCP - these will likely tell you the package types the chips come in and any temperature ranges the devices are suited for.

Regarding the prefix letters, as far as I remember HEF was made by Philips (now NXP), CD by Texas instruments and MC (now On semiconductors).

It wouldn't suprise me if Fairchild also made the CD type too.

If anyone has a comprehensive "how to read components guide" or rule-of-thumb syntax I would appreciate a link as similar occurs with capacitors, transistors and other ICs.

I don't know of one

Andy aka
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  • So the prefix is a series or a company code? It has no effect on the operation of the chip over different companies? – Oliver Kellow Sep 01 '13 at 12:18
  • @OliverKellow, there is no way to know if two companies' version of the chip have the same specs except by comparing the two datasheets. The specs may be identical, but there are cases where they are different. Only by comparing the datasheets will you know if the specs are the same for the chips you are looking at (and the specs that matter for your application). – The Photon Sep 01 '13 at 14:36
  • @OliverKellow usually the prefix is recognizable but what usually is clear is the trademark symbol. For instance TI is a mini map of Texas, Philips (NXP) used to put a circular symbol on with some little stars in it. I think Fairchild is an F in a circle etc etc.. – Andy aka Sep 01 '13 at 21:32