[sdiy] Re: 7400 / 4000 series ICs--compatible?

[Roy J. Tellason]

On Saturday 27 August 2005 03:51 pm, Phil Harbison wrote:
> I'm not familiar with that specific part, but the differences
> between 40xx, 74HCxx, and 74HCTxx parts are primarily related
> to supply voltage and input thresholds.
>
> 40xx:    Vdd ranges from +5V to +15V
> 74HCxx:  Vdd +5V, CMOS compatible input levels
> 74HCTxx: Vdd +5V, TTL compatible input levels

I was of the impression that the 4xxx B-series devices would go down to 3V...