On 06/23/2011 04:50 PM, Jim Thompson wrote:
Anyone measured the actual hysteresis of a 74HC14? The data sheet
claims almost a volt. Is that a reliable number? I don't have any on
hand, so I thought I'd ask before ordering some.

Read the data sheet -- I think you'll find that proper engineering term
is "untrustworthy".

TI lists the high-going switch point as ranging between 1.7 and 3.15
volts, while the low-going switch point ranges between 0.9 and 2.2 volts
-- hopefully without the 3.15 and 2.2 happening on the same part. That
makes sense for noise immunity, but it doesn't quite fly for any but the
coarsest of analog uses to which you may wish to put it.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

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"Applied Control Theory for Embedded Systems" was written for you.
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