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Chapter 5 Operation Guide
2.Operation Features
（1）PRR can be changed during laser operation with the adjustment of
the signal frequency at the pin 20.The time between two adjacent rising
edges should be within the specified range of PRR period. It should be less
than 50 us when the laser is operated at the minimum PRR of 20 kHz. If
the PRR (pin 20) is higher than the upper limit, the laser will be operated at
the maximum specified PRR. If the PRR (pin 20) is lower than the minimum
allowed PRR, the laser will be operated at the minimum specified PRR.
（2）The power setting can be changed during the laser operation by
applying updated values to pin 1-8 and latching them into the laser via pin
9. The laser will respond to the changes on the subsequent specified rise
time.
（3）If pin 18 is HIGH and pin 19 is LOW, there is laser radiation with the
power of less than 20mW.
（4）If the temperature of the laser module e45℃ , the laser will
be automatically switched OFF and the alarm signal will appears on pins
16 and 21. Even if the temperature drops back to under +45℃ , the laser
will not resume the emission and keep the alarm pins unchanged until it is
re-started.
