TTL Logic Chip Designations Prefix/Suffix?

[+Larry]

I've been Googling this, but no luck. Maybe someone has a link?

 

Since I found a problem with a problem with a "plain vanilla" 74LS08 in a 600XL, I've been looking on eBay for replacements. What I find is

HD74LS08P DIP14 HITACHI Logic Circuit, Quad 2-Input AND, LS-TTL

Is there a reference that explains all the prefixes and suffixes? One of my 800XL boards I looked at has a 74LS08N instead of a regular '08. The "N" means inverted logic, doesn't it? But it seems to work ok. Seems odd, but I never got much beyond the truth tables.

 

Thanks,

Larry

 

 

[Dropcheck]

I've been Googling this, but no luck. Maybe someone has a link?

 

Since I found a problem with a problem with a "plain vanilla" 74LS08 in a 600XL, I've been looking on eBay for replacements. What I find is

HD74LS08P DIP14 HITACHI Logic Circuit, Quad 2-Input AND, LS-TTL

Is there a reference that explains all the prefixes and suffixes? One of my 800XL boards I looked at has a 74LS08N instead of a regular '08. The "N" means inverted logic, doesn't it? But it seems to work ok. Seems odd, but I never got much beyond the truth tables.

 

Thanks,

Larry

 

 

 

 

Might help. Try this:

[BillC]

I've been Googling this, but no luck. Maybe someone has a link?

 

Since I found a problem with a problem with a "plain vanilla" 74LS08 in a 600XL, I've been looking on eBay for replacements. What I find is

HD74LS08P DIP14 HITACHI Logic Circuit, Quad 2-Input AND, LS-TTL

Is there a reference that explains all the prefixes and suffixes? One of my 800XL boards I looked at has a 74LS08N instead of a regular '08. The "N" means inverted logic, doesn't it? But it seems to work ok. Seems odd, but I never got much beyond the truth tables.

 

Thanks,

Larry

 

 

The "N" suffix indicates a plastic through-hole DIP package IC.

[+mytek]

Since I found a problem with a problem with a "plain vanilla" 74LS08 in a 600XL, I've been looking on eBay for replacements.

 

I've heard that a 74F08 sometimes works even better, getting rid of some of the delay imposed on the 02 clock. It's a higher speed and higher drive capable drop-in replacement for the older 7408 or 74LS08 chips.

 

- Michael

[Madi]

Nice topic about 74000 series:

https://en.wikipedia.org/wiki/7400_series

 

 

Here is a good labeling code summery

[1050]

I prefer to use 74HCT08 for substitute there, very close to the same speed but higher drive with rail to rail output. 74ACT08 if you want the same but faster performance. I seem to remember a decent logic family speed chart at wiki, but it's nowhere to be seen now? Some of their suggestions are off, CMOS family does rail to rail output, no exceptions allowed. This is decidedly NOT the same as TTL logic levels, yet wiki states similar voltages. Like apples and oranges are both sorta round and that makes them the same.

 

And a bit of re-reading shows the issue to be that proper proofreading in the article itself is a horrible mess.

 

HCT High speed, compatible logic levels to bipolar parts.

should read

HCT High speed, compatible INPUT logic levels to bipolar parts.

output is rail to rail as per CMOS construction. T is elsewhere defined to be compatible with TTL family on input pins.

 

For example, Fairchild Semiconductor manufactures parts with MM and DM prefixes, and no prefixes.

Wow, that's bad.

 

I've been blessed with data books that have such information in the back of them. Real books, 5 pounders some of them. I'm a little dismayed that I can't point you to one at the zenith of the information age.

[+Larry]

Thanks to all for the tips and suggestions! And Madi, that labeling code summary is exactly what I was looking for. I definitely have that bookmarked! When I see the definitions, many/most of the designations make perfect sense.

 

-Larry