4-11
4
IM 701830-01E
Common Operations
4.8
Selecting the Time Base
Function
Selecting the time base
Select the time base from the following choices.
Int
: Internal clock signal (TIME/DIV knob is effective)
Ext : Clock signal input through the external clock input terminal (TIME/DIV knob is
ineffective)
When selecting
“
EXT
”
Apply a clock signal to the terminal that is indicated as “TRIG OUT/EXT CLK IN” (used also
for trigger output) on the left side of the instrument. Follow the specifications shown below.
EXT CLK IN
Connector type
BNC
Frequency range
100 kHz or less (Module 701852 and 701853)
Input level
TTL level (0 to 5 V)
Minimum pulse width
400 ns for High and Low
Applicable module
High-Resolution, High-Voltage, Isolation Module (701852)
High-Resolution, Isolation Module (701853)
Temperature Module (701860)
Logic Input Module (701870)
Strain Module (701880)
32-bits extended logic input
Inapplicable module
High-Speed Isolation Module (701855, 701850)
High-Speed Module (701856, 701851)
Circuit diagram of the external clock input/timing chart
External clock input
Sampling edge
400 ns or more
400ns or more
10
µ
s or more
LCX14
100
Ω
+5 V
CAUTION
Applying a voltage outside 0 to 5 V range to the “TRIG OUT/EXT CLK IN” terminal
can damage the input section.
