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PWM Commands
Use the APPLy command or the equivalent FUNC, FREQ, VOLT, and
VOLT:OFFS commands to configure the carrier waveform.
PWM:SOURce {INTernal|EXTernal}
PWM:SOURce?
Select the source of the modulating signal. The function generator will
accept an internal or external modulation source. The default is INT.
The :SOUR? query returns "INT" or "EXT".
• If you select the External source, the carrier waveform is modulated
with an external waveform. The pulse width or pulse duty cycle
deviation is controlled by the ±5V signal level present on the rear-
panel Modulation In connector. For example, if you have set the pulse
width deviation to 50 µs using the PWM:DEV command, then a +5V
signal level corresponds to a 50 µs width increase. Lower external
signal levels produce less deviation.
PWM:INTernal
:FUNCtion {SINusoid|SQUare|RAMP|NRAMp|TRIangle|NOISe|USER}
:FUNCtion?
Select the shape of the modulating waveform. Used only when the
Internal modulation source is selected (PWM:SOUR INT command). (The
carrier must be a pulse waveform for PWM.) The default is SIN.
The :FUNC? query returns "SIN", "SQU", "RAMP", "NRAM", "TRI",
"NOIS", or "USER".
• Select "SQU" for a square waveform with a 50% duty cycle.
• Select "RAMP" for a ramp waveform with 100% symmetry.
• Select "TRI" for a ramp waveform with 50% symmetry.
• Select "NRAM" (negative ramp) for a ramp waveform
with 0% symmetry.
• If you select an arbitrary waveform as the modulating waveshape
("USER"), the waveform is automatically limited to 4K points.
Extra waveform points are removed using decimation.
Chapter 4 Remote Interface Reference
Pulse Width Modulation (PWM) Commands
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