SNAA345 December   2020 LMK5C33216

 

  1.   Trademarks
  2. Introduction
  3. 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. 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. Wander Tolerance
    1. 4.1 Wander Tolerance G.8262 Option 1
    2. 4.2 Wander Tolerance G.8262 Option 2
  6. Jitter Tolerance
    1. 5.1 Jitter Tolerance G.8262 Option 1 and Option 2
  7. 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. Holdover
    1. 7.1 Holdover G.8262 Option 1
    2. 7.2 Holdover G.8262 Option 2
  9. Free-Run Accuracy
    1. 8.1 Free-Run Accuracy G.8262 Option 1 and Option 2
  10. Pull-In and Hold-In
    1. 9.1 Pull-In Range G.8262 Option 1 and Option 2
  11. 10Conclusion
  12. 11References

Introduction

The LMK5C33216 device is a high-performance network clock generator, synchronizer, and jitter attenuator with advanced reference clock selection and hitless switching capabilities designed to meet the stringent requirements of communications infrastructure applications.

This document contains the summary of the test setups and measured results highlighting compliance to ITU-T G.8262 (Timing characteristics of a synchronous Ethernet equipment slave clock) standard. The device-under-test (LMK5C33216) was configured using Texas Instruments' TICS Pro Silicon EVM Programming Tool. Unless specified otherwise, the LMK5C33216 Digital PLL loop bandwidth for EEC-Option 1 was set to 10 Hz and for EEC-Option 2 to 0.1 Hz.

All measurement results included in this document are for DPLL1. The measurement results for DPLL1 are an accurate representation of compliance characteristics for all three DPLLs. All three DPLLs passed standard compliance test requirements.

Throughout this document, the acronym MTIE stands for maximum time interval error and the acronym TDEV stands for time deviation.

Testing was performed using the Calnex Rb/GPS frequency reference and Calnex Paragon-T hardware. Other test hardware was used as required for the measurements.

Notable features of this high-performance device includes:

  • Hitless Switching with minimal phase transients (< 100 ps)
  • Ultra High-Performance VCO allows use of a low-cost holdover reference without sacrificing performance
  • High-Performance DPLL Channel with Programmable loop bandwidth for jitter and wander filtering suitable for EEC Option 1 and EEC Option 2
  • Reference Priority Selection, Gapped Clock and Runt Pulse Detectors, Automatic/Manual Switchover, Holdover, and Tuning Word History

Table 1-1 DPLL1 ITU-T G.8262 Compliance Summary
SECTIONDESCRIPTIONEEC OPT 1
(SECTION IN G.8262)
EEC OPT 2
(SECTION IN G.8262)
COMPLIANT
WANDER GENERATION
Section 2.1MTIE EEC Option 1; Must not exceed MTIE mask8.1.1Yes
Section 2.2TDEV EEC Option 1; Must not exceed TDEV mask8.1.1Yes
Section 2.3MTIE EEC Option 2; Must not exceed MTIE mask8.1.2Yes
Section 2.3TDEV EEC Option 2; Must not exceed TDEV mask8.1.2Yes
WANDER TRANSFER
Section 3.1Transfer function of the PLL for EEC Option 1 and EEC Option 2; Must meet bandwidth requirements10.110.2Yes
Section 3.2Wander Transfer TDEV G.8262 for EEC Option 2; Must not exceed TDEV mask10.2Yes
WANDER TOLERANCE
Section 4.1Wander Tolerance EEC Option 1; Must tolerate at least input wander defined by MTIE/TDEV mask9.1.1Yes
Section 4.2Wander Tolerance EEC Option 2; Must tolerate at least input wander defined by TDEV mask9.1.2Yes
JITTER TOLERANCE
Section 5.1Jitter Tolerance for EEC Option 1 and EEC Option 2; Must tolerate jitter defined by UI mask9.2.19.2.1Yes
PHASE TRANSIENT GENERATION
Section 6.1Short Term Phase Transient EEC Option 1; Must not exceed limits set by standard11.1.1Yes
Section 6.2Short Term Phase Transient EEC Option 2; Must not exceed MTIE mask set by standard11.1.2
11.4.2
Yes
Section 6.3Phase Transient Generation with Signal Interruptions EEC Option 1; Must not exceed phase variation limit11.3.1Yes
Section 6.4Phase Discontinuity EEC Option 1; Must not exceed phase variation limits11.4.1Yes
Section 6.5Phase Discontinuity EEC Option 2; Must not exceed MTIE mask set by standard11.4.2Yes
HOLDOVER PERFORMANCE
Section 7.1Holdover EEC Option 1; Must not exceed TIE mask set by standard11.2.1Yes
Section 7.2Holdover EEC Option 2; Must meet TIE mask set by standard11.2.2Yes
FREE-RUN ACCURACY
Section 8.1Free-run Accuracy EEC Option 1 and Option 2; Must not exceed ±4.6 ppm6.16.2Yes
PULL-IN AND HOLD-IN
Section 9Pull-in and Hold-in EEC Option 1 and Option 2; Minimum pull-in range and hold-in range must be ±4.6 ppm7.1.17.1.2
7.2.2
Yes