Tektronix AFG3000 Series Manual page 5

Tektronix AFG3000 Series Function Generator Guide v1.0
For a pulse train, the pulse duty cycle (in %) is defined as:
V
Pulse Width = 0.9 ms
5
0
0
Pulse Period = 1.0 ms
Delay=
Pulse Freq
0.3 ms
V
Pulse Width = 0.5 ms
5
0
0
Delay=
Pulse Period = 1.0 ms
0.3 ms
Pulse Freq
V
Pulse Width = 0.1 ms
5
0
0
Delay= Pulse Period = 1.0 ms
0.3 ms
Pulse Freq
Figure 4: Examples of ideal pulse trains (Ampl = 5 V, Offset = 2.5 V or High = 5V, Low = 0 V)
Depending on the situation, a pulse's leading and trailing edge transition times may be relevant:
t
LE
Figure 5: Edge transition widths for a realistic (non-ideal) pulse
Duty = 90%
1
= 1 kHz
Duty = 50%
1
= 1 kHz
Duty = 10%
1
= 1 kHz
90%
50%
10%
t
TE
4
Pulse Width
=
Duty
Pulse Period
2
2
2
t is the leading edge transition time.
LE
t is the trailing edge transition time.
TE
The transition times are specified using the 10%
and 90% amplitude points as references.
If t and t are a significant fraction of the total
LE TE
width, then the 50% amplitude point is a better
reference for specifying the pulse width.
Portland State University
⋅
100
t (ms)
3
t (ms)
3
t (ms)
3