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5-42
IM AQ6373-01EN
Explanation
Data measurement or signal sweeping starts when triggered by an external signal.
An external trigger input terminal is located on the rear panel of the instrument. Input
signals are of TTL levels.
SMPL TRIG:
Measurement starts per external trigger signals. You can set
whether the trigger activates on a rising or falling edge of the signal.
Measurement starts approximately 70
µ
s after the trigger activates.
SWEEP TRIG: Sweeping starts per external trigger signals. The trigger activates on
the rising/falling edge of the signal. Sweeping starts 5 ms at most after
the trigger activates.
Signal Logic and Delay Time (for SMPL TRIG)
EDGE
This key is used to set the external trigger signal detection edges.
RISE The rising edge is recognized as a trigger.
FALL The falling edge is recognized as a trigger.
DELAY ****.*
µ
s
This key is used to set the delay time between trigger signal edge detection and data
measurement. The setting range is 0 to 1000.0
µ
s (fine: steps of 0.1; coarse: steps of 1).
For information about the external trigger measurement function, see section 2.2.
Measurement Sensitivity and Corresponding Pulse Width
The measurement sensitivity is determined based on the light pulse width. Select the
appropriate sensitivity level based on the pulse width in the table below.
Sensitivity Name and Corresponding Pulse Width
Sensitivity
setting
CHOP MODE
On-Screen Notation
Corresponding
Pulse Width
(Min.)
Normal
PEAK HOLD
Setting
EXT TIRG
Setting
NORM/HOLD
OFF
NORM/HOLD P-NORM/HLD
E-NORM/HLD
PEAK: 100
µ
s
EXT: 50
µ
s
NORM/AUTO
NORM/AUTO P-NORM/AUT
E-NORM/AUT
300
µ
s
NORMAL
NORMAL
P-NORMAL
E-NORMAL
1ms
MID
MID
P-MID
E-MID
3ms
HIGH1
HIGH1
P-HIGH1
E-HIGH1
10ms
HIGH2
HIGH2
P-HIGH2
E-HIGH2
50ms
HIGH3
HIGH3
P-HIGH3
E-HIGH3
200ms
MID
SWITCH
MID/SW
P-MID/SW
E-MID/SW
3ms
HIGH1
HI1/SW
P-HI1/SW
E-HI1/SW
10ms
HIGH2
HI2/SW
P-HI2/SW
E-HI2/SW
50ms
HIGH3
HI3/SW
P-HI3/SW
E-HI3/SW
200ms
5.15 External Trigger Measurement