User’s Manual MSO/UPO2000 Seri es
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(3)
Trigger Coupling
Trigger coupling determines which part of the signal will be transmitted to the trigger circuit. The
coupling type includes DC, AC, LF reject, HF reject and noise reject.
a.
DC
：
Let all the components of the signal pass through
b.
AC
：
Block the DC component of the signal
c.
HF reject: Attenuate high frequency components over 40 kHz.
d.
LF reject: Attenuate low frequency components below 40 kHz.
e.
Noise reject: Suppress high frequency noise in the signal to reduce probability of touch error.
(4) Pretrigger / Delayed Trigger
Before trigger event / after collect data.
Trigger position is usually set at the horizontal center of the screen, user can observe 7 grids of
pretrigger and delay trigger information. Horizontal move the waveform to view more pretrigger
information. By observing the pretrigger data, the waveform before generated can be observed. For
example, capturing the glitch at the start of the circuit, observing and analyzing the pretrigger data to
find out the cause of the glitch.
(5) Force Trigger
Press FORCE key to force to generate a trigger signal. If waveform is not displayed on the screen in
normal or single trigger mode, press FORCE key to sampling signal baseline and ensure the sampling is
performed properly.
7.2 Edge Trigger
The edge can be identify by looking for the specific edge (rising edge, falling edge and rising & falling edge)
and electrical level. Press edge trigger menu to set source, trigger coupling, trigger mode and edge type.
Waveform can be stable generated when the condition is satisfied, as shown in Figure 7-1.
Figure 7-1
Rising edge
Falling edge
Trigger point
