SPRS976E November 2016 – May 2018 DM505
PRODUCTION DATA.
To evaluate the frequency of a digital signal, an estimated rule of thumb is to consider its bandwidth fBW with respect to its rise time, tR:
fBW ≈ 0.35 / tR
This frequency actually corresponds to the break point in the signal spectrum, where the harmonics start to decay at 40 dB per decade instead of 20 dB per decade.