Losing sight of the numbering scheme
One of the nice features of the 74*00 line of logic is that, for the most part, the function is consistent across technologies.
But...
I find myself in need of some open-collector drivers to fit in a small space. The outputs may be subject to significant voltages in the OFF state.
A 7407 fills the bill nicely. Well, apart from the "small space" aspect. And, er, the 0 to 70°C rating.
The signature feature of the 7407 is the high-voltage outputs, rated for 30V. If you only need 15V outputs, there's the 7417. I don't recall offhand whether there was a 5V-output counterpart, and don't feel like digging out the ancient TI databook just now.
So: what's a modern version of a 7407 (hey, even a 7417 would do), with at least an I-temp rating, and available in a TSSOP?
Well... I find things like 74LV07, and 74AUC07.
Which, well... when I look at the absolute maximum ratings, I see an output voltage rating that's the same as the supply voltage rating.
Not very '07 at all, really.
A bit of further digging reveals that the 74LS07 is still around, has 30V outputs, and is available in a TSSOP... but the 54LS07, which would have met the temperature requirement, is obsolete.
Grrr.
Ah, well. More digging to do. If all else fails, use discrete FETs in tiny packages....


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