THORLABS IP250-BV, Руководство пользователя

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IP250-BV Blue Laser Diode Controller Chapter 2: Setup and Operation
Page 4 10713-D02
5. Using a digital multimeter measure the ILIM Test point with respect to the
TP GND Test point (all measurements will be with respect to TP GND).
Adjust the ILIM ADJ potentiometer for the maximum current that the laser
must be limited to. The transfer function is 1 V = 1 A, with a maximum
adjustment of approximately 0.250 V or 250 mA.
6. If a monitor photodiode (MPD) is connected, measure the PLIM Test point
and adjust the PLIM ADJ pot for the maximum MPD current expected.
The transfer function is 1 V = 1 mA, with a maximum adjustment of 2.5 V
or 2.5 mA.
When operating in ACC the PLIM (power limit) function is still active if the
MPD current reaches the limit point. This is especially helpful if the laser
is to be operated at varying temperatures where the efficiency may
change to the point where the operating current will overdrive the laser.
The PLIM will always keep the laser in a safe operating area when
properly set.
If no MPD is connected always set the PLIM ADJ fully clockwise.
7. The P/I ADJ Pot will allow adjustment of the laser drive current from 0 mA
to the ILIM set point or 250 mA max. When turning on a laser for the first
time it is suggested that this pot be set fully counterclockwise.
8. Press and release the ENABLE switch.
9. The green LD ON indicator will turn on.
NOTE: There will always be a delay until full power of approximately 2 to
3 seconds before any current can flow to the laser diode.
10. Adjust the P/I ADJ potentiometer clockwise to increase the injection
current of the laser diode. The Ild Test point provides an analog read back
of the actual laser current, 1 V = 1 A. The Ipd Test point provides an
analog read back of the Photodiode monitor current, 1 V = 1 mA and can
be used to gauge the relative output power of the laser.
11. Pressing the ENABLE switch while the laser is operating will turn off the
laser current.
If the ALARM indicator turns ON see “Alarms and Troubleshooting” below.
NOTE: If the ILIM setting is below approximately 10 mA the I LIMIT LED will be
ON, this is normal.
If the current is adjusted to its maximum limit then the I LIMIT indicator will turn
ON. This indicator is active when the injection current is approximately 95% of the
maximum limit.
If the photodiode is connected and the PLIM is set to a value requiring less than
the maximum current set by ILIM, the I LIMIT indicator will NOT turn ON and the
unit will operate in constant power at the power limit level set by PLIM.