
19-16 Electrical Variables
the scope’s measurements in two ways. First are narrow pulses. Figure 19.10 shows the same 5 ns
wi
de
pu
lse
be
ing
di
splayed
on osc
illoscopes
of 50
0
an
d
60 MH
z
ba
ndwidths,
an
d
th
e
e
ect
of th
e
lo
wer
ba
ndwidth
on th
is
ev
ent
th
at
is cl
osest
to th
e
ri
se
ti
me
of th
e
sl
ower
sc
ope
is ap
parent
.
e second is fast time interval measurements. A measurement of signal rise time is an example.
e obs
erved
ri
se
ti
me
on th
e
sc
ope’s
di
splay
is acc
ording
to Eq
uation
19.3:
t t t
observed signal scope
= +( )
/2 2 1 2
(19.3)
If a 10 ns rise time were to be measured with a 100 MHz scope, one would obtain a measure-
ment of 10.6 ns based on