THORLABS ITC1 Series, Operation Manual

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© 2018 Thorlabs GmbH
4 Operating Instruction
15
4.2 Connecting Laser Diode and Photo Diode
The ITC1xx OEM controllers are designed to drive laser diodes up to a maximum current of
0.2 A, 1 A or 3 A, depending on the type, either with laser diode anode or cathode grounded.
The laser diode is always sourced with respect to ground. Compared to a floating driver stage,
this operation mode is advantageous with respect to laser diode protection and to the stability
of the laser current.
The photodiode can be used either floating, or with anode or cathode grounded. Additionally, a
bias voltage can be applied.
Connect the laser diode and the photodiode using shielded, twisted pair cables. The anode and
cathode connection of each device should be twisted.
Warning
Disconnecting the laser diode during operation may destroy the laser diode!
Below are shown possible configurations of the laser and monitor (photo) diode combination
and the connection scheme to the output connectors ST2 or ST1.
AG = Anode Grounded
CG = Cathode Grounded