Functional Description

02066-DSH-001-D

Mindspeed Technologies

®

9

Preliminary Information / Mindspeed Proprietary and Confidential

3.3

Modulator

The M02066 modulation output is optimized for driving a 25

OUT- is 0.6V. To interface with the laser diode, a matching resistor (RD) is required for impedance matching. An

RC shunt network is necessary to compensate for the laser diode parasitic inductance, thereby improving the

optical eye.

These values will need to be optimized for a specific laser.Any capacitive loading at the cathode of a laser diode will

degrade the optical output performance. An inductor is used to isolate the BIAS pin from the laser cathode. See

Figure 3-1.

The modulator output stage is designed to drive up to 85mA in either AC-coupled or DC-coupled mode. DC-

coupled performance depends on the laser used.

Figure 3-2.

Modulation C urrent in m A

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3040

Rmodse t (kohms)