THORLABS LD2000R, Руководство пользователя

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OEM Laser Diode Driver Chapter 5: Operating the LD2000R
Rev I, May 21, 2018 Page 11
5.3. Operating Modes
NOTE
For all modes of operation, we recommend using a linear DC power supply or
battery. Although the LD2000R provides over -60 dB of power supply
suppression, switch-mode power supplies should be avoided due to the
inherent transients in their output.
5.3.1. CW Operation
To operate the LD2000R in a CW mode, follow the steps below.
1. Connect your laser diode to the appropriate pins (11, 12, 13)
2. Attach a suitable DC voltage supply to pins 9 and 10. The power supply
should be bypassed near the LD2000R with a 10 µF tantalum capacitor
and a 0.1 µF ceramic capacitor.
3. Short pins 5 and 6 to use the on-board PD Current Trimpot.
4. Short pins 14 and 15 to use the on-board Current Limit Trimpot.
5. Short pin 3 to ground to set analog modulation to FULL ON.
6. Short pin 16 to ground.
7. Turn both the PD Current Trimpot and the Current Limit Trimpot
counterclockwise 20 turns each to set these at their minimum operating
points.
8. Turn the DC power supply on and use a voltmeter to monitor the LIMIT
OUT on pin 18.
9. Adjust the Current Limit Trimpot clockwise slowly while observing the
LIMIT OUT to set the maximum operating current for your laser (refer to
laser manufacturer's data sheets). Note, this output is 40 mA/V.
10. Using a calibrated power meter to monitor the diode laser output, slowly
adjust the PD Current Setpoint trimpot clockwise to obtain the desired
operating power level. The laser will begin to emit upon reaching the drive
current threshold.
5.3.2. Analog Modulation
To operate the LD2000R analog modulation feature, follow the setup procedures
for CW Operation to establish the laser operating conditions. Once the LD2000R
has been setup for your laser, remove the short from pin 3 to ground and apply a
positive voltage to pin 3 to modulate the laser.