THORLABS ITC502 Operation Manual page 36

1.9 Connecting components
integrated monitor diode and shared ground connector) use two separate wires for
pin 2 (PD ground) and pin 3 (LD ground) and connect them only once as close as
possible to the laser diode to avoid measurement errors when measuring the monitor
diode current.
In this case the following pin assignment of the output jack will be valid:
(pins in () for voltage measurement)
(6) 7 4
LD
2 (PD)
(9)
3 (LD)
Figure 10
(LD) = laser diode
ITC500 / page 28
(6) 7 4
PD
LD
2 (PD)
(9)
3 (LD)
Connecting laser- and monitor diode
(9) 8 4
LD
PD
2 (PD)
(6)
3 (LD)
(PD) = monitor (photo-) diode
(9) 8 4
PD
LD PD
2 (PD)
(6)
3 (LD)