EZ Digital OS-5060A, Operation Manual

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Period, Pulse. Width, and Duty Cycle. The basic technique described in the
preceeding paragraph can be used to determine pulse parameters such as period, pulse
width, duty cycle, etc.
The period of a pulse or any other waveform is the time it takes for one full
cycle of the signal. In Figure 2-8, the distance between points (A) and (C) represent one
cycle ; the time interval of this distance is the period. The time scale for the CRT display
of FIGURE 2-8. A is 10ms/div, so the period is 70 milliseconds in this example.
Pulse width is the distance between points (A) and (B). In our example it is
conveniently 1.5 divisions, so the pulse width is 15 milliseconds. However, 1.5
divisions is a faster sweep speed for this particular measurement. Increasing the sweep
speed to 2ms/div as in Figure 2-8. B gives a large display, allowing more accurate
measurement. An alternative technique useful for pulses less than a division wide is to
pull the A VARIABLE knob (25) for X10 magnification, and reposition the pulse on
screen with the Horizontal POSITION control (26). Pulse width is also called on time in
some application. The distance between points (B) and (C) is then called of time. This
can be measured in the same manner as pulse width.
When pulse width and period are known, duty cycle can by calculated. Duty
Cycle is the percentage of the period (or total of on and off times) represented by the
pulse width (on time)
PW (100) A
→
B (100)
Duty cycle (%) = =
Period A
→
C
15ms
×
100
Duty cycle example = = 21.4%
70ms
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