Keysight 33210A, User Manual

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Chapter 3 Features and Functions
Pulse Width Modulation (PWM)
3
Duty Cycle Deviation
The duty cycle deviation represents the variation in duty cycle of the
modulated waveform from the duty cycle of the pulse waveform. The
duty cycle deviation is expressed as a percentage of the period.
• Duty cycle deviation: 0 to 100% (see below). The default is 1%.
• The duty cycle deviation cannot exceed the current pulse duty cycle.
• The duty cycle deviation is also limited by the minimum pulse width
(Wmin):
Duty Cycle Deviation < Duty Cycle – 100 X Wmin ÷ Period
and
Duty Cycle Deviation < 100 – Duty Cycle – 100 X Wmin ÷ Period
where:
Wmin = 40 ns for period < 10 s.
Wmin = 200 ns for period > 10 s, but < 100 s.
Wmin = 2 µs for period > 100 s, but < 1000 s.
• The duty cycle deviation is also limited by the current edge time
setting.
Duty Cycle Dev < Duty Cycle – (160 X Edge Time) ÷ Period
and
Duty Cycle Dev < 100 – Duty Cycle – (160 X Edge Time) ÷ Period
• Front-Panel Operation: After enabling PWM, press the
Dty CyC Dev
softkey. Then use the knob or numeric keypad to enter the desired
deviation.
• Remote Interface Operation:
PWM:DEViation:DCYCle {<
deviation in percent
>|MIN|MAX}
Note:
The pulse width and width deviation, and the pulse duty cycle and
duty cycle deviation are coupled in the front panel interface. If you select
Width
for the pulse waveform and enable PWM, the
Width Dev
softkey is
available. On the other hand, if you select
Dty Cyc
for the pulse waveform
and enable PWM, the
Dty Cyc Dev
softkey is available.
33210A users guide.book Page 88 Wednesday, July 16, 2008 11:16 AM