DS31408GN+ Maxim Integrated Products, DS31408GN+ Datasheet - Page 5

• Manufacturer Part Number: DS31408GN+
• Description: IC SONET/SDH SYNC CSBGA
• Manufacturer: Maxim Integrated Products

Specifications of DS31408GN+

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 90-31408+GN0

Detailed Features
Input Clock Features
DPLL Features
Digital Frequency Synthesizer Features
Output APLL Features
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Eight input clocks, differential or CMOS/TTL signal format
Input clocks can be any frequency from 2kHz up to 750MHz
Supported telecom frequencies include PDH, SDH, Synchronous Ethernet, OTU-1, OTU-2, OTU-3
Per-input fractional scaling (i.e., multiplying by ND where N is a 16-bit integer and D is a 32-bit integer
and N < D) to undo 64B/66B and FEC scaling (e.g., 64/66, 238/255, 237/255, 236/255)
Special mode allows locking to 1Hz input clocks
All inputs constantly monitored by programmable activity monitors and frequency monitors
Fast activity monitor can disqualify the selected reference after a few missing clock cycles
Frequency measurement and frequency monitor thresholds with 0.2ppm resolution
Three optional 2/4/8kHz frame-sync inputs
Very high-resolution DPLL architecture
Sophisticated state machine automatically transitions between free-run, locked, and holdover states
Revertive or nonrevertive reference selection algorithm
Programmable bandwidth from 0.5mHz to 400Hz
Separately configurable acquisition bandwidth and locked bandwidth
Programmable damping factor to balance lock time with peaking: 1.2, 2.5, 5, 10, or 20
Multiple phase detectors: phase/frequency and multicycle
Phase/frequency locking (360 capture) or nearest edge phase locking (180 capture)
Multicycle phase detection and locking (up to 8191UI) improves jitter tolerance and lock time
Phase build-out in response to reference switching for true hitless switching
Less than 1 ns output clock phase transient during phase build-out
Output phase adjustment up to 200ns in 6ps steps with respect to selected input reference
High-resolution frequency and phase measurement
Holdover frequency averaging over 1-second, 5.8-minute, and 93.2-minute intervals
Fast detection of input clock failure and transition to holdover mode
Low-jitter frame sync (8kHz) and multiframe sync (2kHz) aligned with output clocks
Seven independently programmable DFS blocks
Each DFS can slave to either of the DPLLs
Each DFS can synthesize any 2kHz multiple up to 77.76MHz
Per-DFS phase adjust (1/256UI steps)
Approximately 40ps RMS output jitter
Simultaneously produce three high-frequency, low-jitter, rates from the same reference clock, e.g.,
622.08MHz for SONET, 255/237*622.08MHz for OTU2, and156.25MHz for 10GE
Standard telecom output frequencies include 622.08MHz, 155.52MHz, and 19.44MHz for SONET/SDH
and 156.25MHz, 125MHz, and 25MHz for Synchronous Ethernet
Very high-resolution fractional scaling (i.e., noninteger multiplication)
Less than 1ps RMS output jitter
ABRIDGED DATA SHEET
DS31408
5