What is slew (transition time), and why does it matter?
From PDVerse STA Mentor Guide · pdVerse Mentor Guide
Short Answer
Slew, also called transition time, is the amount of time it takes a signal's waveform to swing between two defined threshold points, commonly the 20 percent and 80 percent levels.
Example
The definition given is slew = t(80%) - t(20%), meaning you measure the time between the waveform crossing the 20 percent point and crossing the 80 percent point.
Why It Matters
Because slew is measured as a time duration, a small slew number actually means a fast, sharp-edged signal, while a large slew number means a slow, lazy edge. The notes flag this directly as a common point of confusion for beginners, since intuitively you might expect bigger numbers to mean 'faster.'
Equation
slew = t(80%) - t(20%)Mentor Note — Common Mistake
Don't assume a bigger slew value means a quicker transition. Remember it's the opposite: small slew equals sharp and fast, large slew equals slow and sluggish.
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