LMC10ZEG Datasheet, PDF (9/14 Pages) Bookham, Inc. – 10Gb/s Compact InP MZ Modulator with DWDM Laser

Data Sheet
Wavelength Locker for the LMC10ZEG
The wavelength locker for the LMC10ZEG includes two photodiodes: the Reference photodiode provides a photocurrent
proportional to the laser chip facet power, and the Etalon photodiode provides a photocurrent related to wavelength (frequency).
In order to lock the LMC10ZEG wavelength, a control circuit should be used which maintains the laser submount temperature
constant over life and then controls the wavelength by varying the laser forward current to keep the ratio of the etalon and
reference photodiode currents (Locking Ratio) constant. This may be achieved by keeping the discrimination value (LR x Iref) – Iet)
at zero, where LR is the target Locking Ratio.
Refer to applications document AN0142 for further information on wavelength locking.
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