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ONET1151L: Can I use a ONET1151L laser-driver for OC192/STM-64 application?

Part Number: ONET1151L
Other Parts Discussed in Thread: DS125DF111

Good day ! 

We are want to use a ONET1151L laser-driver for OC192/STM-64 application. 

The requirement in the ITUT G.813 with respecting STM-64 for jitter value at transmitter point is 0.1UI (or about 10ps).

With respect to “Typical Transmitter Test Results” for reference optical module, as shown in eye-diagrams, the jitter value is about 15-17ps (14-15 ps/div), and measured PPJ value is about 15ps.

How these results are satisfied to the ITU-T standard requirements?

Can we use ONET1151L laser-driver for STM-64?

  • Hello Roman,

    An engineer has been assigned, but response will be delayed due to holidays,

    Regards,

    JMMN

  • Hi Roman,

    Data sheet eye calls for 14.8ps per division. Total jitter is about 20% or 30% of the 14.8ps. This means total jitter is about 5ps. Please note the followings:

    1). STM-64 uses a band pass filter from 4MHz to 80MHz. Data sheet eye diagrams does not use a filter and refers to total jitter(no filter).

    2). ONET1151L does not have a CDR to attenuate jitter - it is basically a buffer. Therefor the amount of jitter is highly dependent on the ASIC or FPGA driving the ONET1151L device. Normally a CDR with a low loop bandwidth would drive ONET device and would attenuate the jitter within the loop bandwidth.

    3). Please consider using DS125DF111 as CDR to drive ONET1151L device. DS125DF111 has low loop bandwidth - in order of 10MHz - and would attenuate the FPGA or ASIC jitter in the STM-64 jitter frequency band. Please note, you may need to optimize DS125DF111 register setting to allow the device to lock to the STM data rates.

    Rwegards,, Nasser