SNAA345 December   2020 LMK5C33216

 

  1.   Trademarks
  2. 1 Introduction
  3. 2 Wander Generation
    1. 2.1 Wander Generation MTIE Option 1, G.8262 EEC Option 1
    2. 2.2 Wander Generation TDEV G.8262 EEC Option 1
    3. 2.3 Wander Generation MTIE Stratum ITU-T G.8262 EEC Option 2
    4. 2.4 Wander Generation TDEV G.8262 EEC Option 2
  4. 3 Wander Transfer
    1. 3.1 Transfer Function of the PLL for Option 1 and Option 2
    2. 3.2 Wander Transfer TDEV G.8262 Option 2
  5. 4 Wander Tolerance
    1. 4.1 Wander Tolerance G.8262 Option 1
    2. 4.2 Wander Tolerance G.8262 Option 2
  6. 5 Jitter Tolerance
    1. 5.1 Jitter Tolerance G.8262 Option 1 and Option 2
  7. 6 Phase Transient Generation
    1. 6.1 Short-Term Phase Transient Response G.8262 Option 1
    2. 6.2 Short-Term Phase Transient Response G.8262 Option 2
    3. 6.3 Phase Transient Generation With Signal Interruptions G.8262 EEC Option 1
    4. 6.4 Phase Discontinuity G.8262 Option 1
    5. 6.5 Phase Discontinuity G.8262 Option 2
  8. 7 Holdover
    1. 7.1 Holdover G.8262 Option 1
    2. 7.2 Holdover G.8262 Option 2
  9. 8 Free-Run Accuracy
    1. 8.1 Free-Run Accuracy G.8262 Option 1 and Option 2
  10. 9 Pull-In and Hold-In
    1. 9.1 Pull-In Range G.8262 Option 1 and Option 2
  11. 10Conclusion
  12. 11References

4.1 Wander Tolerance G.8262 Option 1

A PLL that is locked to an input clock must be able to tolerate the wander defined in figure 5 in the G.8262 specification. The definition of tolerance is such that the device will not trigger any alarms while locked to such an input clock and it will be able to pull-in to such as an input clock. Test signals with a sinusoidal phase variation can be used, according to the levels in Table 4-1 (Table 9 in the G.8262 specification), to check conformance to the mask in figure 5 in the G.8262 specification.

Test signals with sinusoidal phase variation according to levels shown in Table 4-1 were introduced using the Calnex Paragon-T box. There were no amplitude, frequency, or missing clock cycle alarms flagged by the LMK5C33216 DUT (10-Hz loop bandwidth). The device stayed locked and was able to pull-in to the input clock throughout the duration of this test. The LMK5C33216 showed a passing result for the wander tolerance G.8262 Option 1 specification.

Table 4-1 Lower Limit of Maximum Tolerable Sinusoidal Input Wander for EEC-Option 1(1)
PEAK-TO-PEAK WANDER AMPLITUDEWANDER FREQUENCY
A1 (µs)A2 (µs)A3 (µs)f4 (mHz)f3 (mHz)f2 (mHz)f1 (Hz)f0 (Hz)
0.25250.320.8160.1310
(1) Table 4-1 shows the resultant requirements