UNI-T UTG1000A User Manual page 67

UTG1000A Series Function Generator User Manual
When modulation source is internal, modulation wave can be: sine wave, square wave, rising ramp
wave, falling ramp wave, arbitrary wave and noise, and the default wave is sine wave. If need to change,
press Carrier Wave ParameterModulation Waveform in turn.
 Square wave: duty cycle 50%
 Lead Ramp Wave: symmetry degree is 100%
 Tail Ramp Wave: symmetry degree is 0%

Arbitrary Wave: Arbitrary wave length limit is 1kpts
 Noise: White Gauss noise
2) External Source
When modulation source is external, carrier wave waveform will be modulated by an external
waveform.
Modulation Shape Frequency Setting
When modulation source is internal, frequency of modulation wave can be modulated (range is
2mHz~20kHz). After enabling PWM function, the default of modulation wave frequency is 1kHz. If need
to change, press Carrier Wave Parameter→Modulation Frequency in turn. When modulation source is
external, carrier wave waveform (pulse wave) will be modulated by an external waveform. The range of
modulation signal input from external is 0Hz to 20kHz.
Duty Cycle Deviation Setting
The duty cycle deviation represents the difference between the duty cycle of the modulated waveform
and the current carrier's duty cycle. Settable range of PWM duty cycle is from 0% to 49.99%, and the
default value is 20%. If need to change, press Parameter→Duty Cycle Deviation in turn.
 The duty cycle deviation represents the difference between the duty cycle of the modulated
waveform and the duty cycle of the original pulse waveform, represented in %.
 Duty cycle deviation cannot be beyond the duty cycle of current pulse wave.
 Sum of duty cycle deviation and the current pulse wave duty cycle must no more than 99.99%.
 Duty cycle deviation is limited by the minimal duty cycle of pulse wave and current edge time.
Comprehensive Example
Make the instrument work in pulse modulation (PWM) mode, then set a sine wave with 1kHz from the
internal of the instrument as a modulation signal and a pulse wave with 10kHz frequency, 2Vpp
amplitude and 50% duty cycle as a carrier wave signal, finally, set duty cycle deviation to 40%. Specific
steps are seen as following:
1) Enable Pulse Width Modulation (PWM) Function
Press Menu→Modulation→Type→Pulse Width Modulation in turn to start the PWM function.
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