TFG2900A Series Function/Arbitrary Waveform Generator Users’ Guide
Suin Instruments Co., Ltd
34
0Vdc, phase difference’s displaying value will match with the real phase difference.
3.5.7 Sync output
: Sync signal’s duty cycle is 50%, sync signal’s frequency is equal to
modulation’s frequency, sync signal’s phase takes modulation signal’s phase as reference.
3.6 Pulse Width Modulation
In pulse width modulation, carrier’s pulse width changes with the modulation signal’s transient
voltage.
3.6.1
Function selection
: Press
【
Modulate
】
to enter modulation function, and then press
〖
Type
〗
to display modulation type menu, press
〖
PWM
〗
, modulation type will be PWM, and display the
pulse width modulation’s waveform diagram and pulse width modulation menu.
3.6.2 Carrier setting
: In pulse width modulation, we can only use pulse wave. If present wave is
not pulse wave, instrument will change it to pulse automatically. Press
【
CH1
】
to enter carrier
parameter interface, you can set carrier wave’s parameter. Press
【
Modulate
】
to enter modulation
parameter setting interface to set its parameter.
3.6.3 Pulse width deviation
: Press
〖
WidthDev
〗
, you can set pulse width deviation value. Pulse
width deviation means in the pulse width modulation, the percent of carrier wave’s pulse width
variation quantity to pulse width setting value when modulation signal reaches full amplitude. In
modulation signal’s positive full amplitude value, output signal’s pulse width is equal to pulse
width setting value plus pulse width deviation. While in negative full amplitude value, output
signal’s pulse width is equal to pulse width setting value minus pulse width deviation.
3.6.4 Modulation frequency
: Press
〖
ModFreq
〗
to set modulation signal’s frequency value.
Modulation frequency is usually far lower than carrier frequency.
3.6.5 Modulation waveform
: You can use most of built-in waveform as modulation waveform,
but some of them may be not suitable. Press
〖
Shape
〗
to choose modulation waveform. After
choosing it, press
〖
Back
〗
, return to modulation menu.
3.6.6
Modulation source
: Press
〖
Source
〗
to choose modulation source. If’ Internal’ is chosen,
instrument will use internal modulation source, modulation frequency and waveform setting is
effective. If ‘External’ is chosen, instrument will use external modulation source, modulation
frequency and waveform setting will be ignored. Input modulation signal from rear panel’s
《
Mod
