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Williams, 1988You're currently viewing posts by Pinsider yonkiman.
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Maybe, maybe not. 74F08 (F stands for "fast") have much faster edges and consume much more current than the 7408. The current probably won't be a big deal, but the fast edges can sometimes cause problems or even EMI (electro-magnetic interference).
That said, if it was me, and I needed a 7408 and only had a 74F08, I'd give it a try. I can't see any harm in it (unless you damage the PCB traces wile desoldering/soldering - be careful).
Good luck!
LS would probably be better.
Here's a web page with a cool chart to show if a logic family will work with a different logic family:
http://www.piclist.com/techref/logic/family.htm (See table 9.2)
Quoted from G-P-E:Plain 7400 series parts are getting harder and harder to stock and cost has gone wayyy up.
74F or 74S for high current loads.
74S has been phased out and replaced by 74F.... but are both identical (as far as we're concerned).
74LS or 74HCT for low current loads.
74LS is slowly being phased out in favor of 74HCT. Seems each week I get another DMSMS report listing more ICs hitting the obsolete status.
Solenoid drivers have a 560 ohm pullups on outputs. That amounts to about an 8mA load which maxes out the 74LS parts and exceeds the limits of 74HCT parts. Need to use high current 74F or 74S here.
Switch drivers have 4.7K ohm pullups on outputs. That amounts to about a 1mA load -- any of the above parts would work. I would advise the 74LS08 as he has a little bit more 'umph' than the 74HCT08.
Ahh...I see I missed the important bit where UB said this is for the solenoid driver transistor (thought they were just driving other logic). G-P-E's right - the main spec that matters for that is that the minimum sink current be high.
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Pacific Grove, CA