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Replacements for 74LS series

JTeach

Oct 6, 2014
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Oct 6, 2014
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Greetings! I've discovered that our inventory only has the 74 LS series for the basic logic gates. Since these need 5V and the other chips I'm using can run off a 9V battery I'm in need of a different line of ICs. I've heard that CMOS will meet my needs but I can't find the matching part numbers for these:

74LS08
74LS04
74LS00
74LS02
74LS86
74LS32

If someone happens to know them, or a site where I can easily look them up, your help would be appreciated.

(I've already looked into using a voltage converter and ruled it out for this particular project).
 

Supercap2F

Mar 22, 2014
550
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Mar 22, 2014
Messages
550
Here's what I could find, it's out of the book "CMOS Cook Book" by Don Lancaster.
TTLCMOS
[TR1][TD]74LS08[/TD][TD1]4081[/TD1][/TR1][TR2][TD2]74LS04[/TD2][TD]4009 or 4049[/TD][/TR2][TR1][TD1]74LS00[/TD1][TD2]4011[/TD2][/TR1][TR2][TD2]74LS02[/TD2][TD]4001[/TD][/TR2][TR1][TD]74LS86[/TD][TD1]4030[/TD1][/TR1][TR2][TD2]74LS32[/TD2][TD]4071[/TD][/TR2]
I don't know how accurate it is, so you will need to double check.
Dan​
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Jan 21, 2010
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Other alternatives include using a 5V regulator. Even with a regulator you may find that the current draw from TTL (even LS-TTL) is higher than you're happy with.

74HC series CMOS is also 5V, but operates at much lower current (at least at all but high frequencies).

74AHC is similar except that it has TTL compatible input voltages.

In these cases the part numbers you need are easily obtained. 74LS08 -> 74HC08 -> 75AHC08. The pinouts are also the same -- you should check because 4000 series CMOS may not be!

There are also exotic (or more exotic) logic families with similar names that operate at different voltages. In particular there are low voltage parts which can operate down to 1.8V. Most (but certainly not all) 74xxCxxx CMOS has an absolute max voltage of 7V. This is higher than equivalent TTL, but not high enough to allow you to use your 9V battery. (Also I don't recommend that you play on the edge of "absolute maximums).
 
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