Functional Description

02066-DSH-001-D

Mindspeed Technologies

®

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Preliminary Information / Mindspeed Proprietary and Confidential

There are two safety features integrated into the MPC loop; an Over-Current Alarm and an MPC loop failure alarm.

The Over-Current Alarm (OCA) circuit limits the maximum bias current generated by the M02060. The bias current

3.5

Safety Logic

Safety logic is provided in order to limit the maximum bias current. The bias current at which the safety logic trips

flag OCA is asserted LOW. A loop failure alarm is also provided to detect when the bias current can no longer be

adjusted to achieve the desired average optical power.

3.6

Data Input Latch

To minimize input data pattern-dependent jitter, a differential clock signal can be connected to the data input latch.

If CEN is HIGH, the input data is retimed by the rising edge of CLK+. If CEN is LOW, the input data is directly

connected to the output stage. If CEN is left floating it will be pulled HIGH by the internal circuitry. When this latch

3.7

Enable Control

The M02066 incorporates a dual laser driver enable function. When ENA is LOW or DIS is HIGH, both the bias

and modulation currents are off. DIS and ENA are available on the M02066 die only, DIS is available on the BCC

package only, ENA is available on the TQPF package.

Figure 3-4.

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