Features
▪ Four independent timing channels
• Each can act as a frequency synthesizer, jitter attenuator,
Digitally Controlled Oscillator (DCO), or Digital Phase Lock
Loop (DPLL)
• DPLLs generate telecom compliant clocks
▪ Compliant with ITU-T G.8262 for Synchronous Ethernet
▪ Compliant with legacy SONET/SDH and PDH
requirements
• DPLL Digital Loop Filters (DLFs) are programmable with cut
off frequencies from 12µHz to 22kHz
• DPLL/DCO channels share frequency information using the
Combo Bus to simplify compliance with ITU-T G.8273.2
• Switching between DPLL and DCO modes is hitless and
dynamic
▪ Automatic reference switching between DCO and DPLL
modes to simplify support for an external phase/time input
interface in a T-BC
• Generates output frequencies that are independent of input
frequencies via a Fractional Output Divider (FOD)
• Each FOD supports output phase tuning with 1ps resolution
▪ 8 Differential / 16 LVCMOS outputs
• Frequencies from 0.5Hz to 1GHz (250MHz for LVCMOS)
• Jitter below 150fs RMS (10kHz to 20MHz)
• LVCMOS, LVDS, LVPECL, HCSL, CML, SSTL, and HSTL
output modes supported
• Differential output swing is selectable: 400mV / 650mV /
800mV / 910mV
• Independent output voltages of 3.3V, 2.5V, or 1.8V
• LVCMOS additionally supports 1.5V or 1.2V
• The clock phase of each output is individually programmable
in 1ns to 2ns steps with a total range of ±180°
▪ 7 differential / 14 single-ended clock inputs
• Support frequencies from 0.5Hz to 1GHz
• Any input can be mapped to any or all of the timing channels
• Redundant inputs frequency independent of each other
• Any input can be designated as external frame/sync pulse of
PPES (pulse per even second), 1 PPS (Pulse per Second),
5PPS, 10 PPS, 50Hz, 100Hz, 1 kHz, 2 kHz, 4kHz, and 8kHz
associated with a selectable reference clock input
• Per-input programmable phase offset of up to ±1.638s in
1ps steps
▪ Reference monitors qualify/disqualify references depending on
LOS, activity, frequency monitoring, and/or LOS input pins
• Loss of Signal (LOS) input pins (via GPIOs) can be assigned
to any input clock reference
▪ Automatic reference selection state machines select the active
reference for each DPLL based on the reference monitors,
priority tables, revertive / non-revertive, and other
programmable settings
▪ System APLL operates from fundamental-mode crystal: 25MHz
to 54MHz or from a crystal oscillator
▪ System DPLL accepts an XO, TCXO, or OCXO operating at
virtually any frequency from 1MHz to 150MHz
▪ DPLLs can be configured as DCOs to synthesize Precision
Time Protocol (PTP) / IEEE 1588 clocks
• DCOs generate PTP based clocks with frequency resolution
less than 1.11 × 10-16
▪ DPLL Phase detectors can be used as Time-to-Digital
Converters (TDC) with precision below 1ps
▪ Supports 1MHz I2
C or 50MHz SPI serial processor ports
▪ The device can configure itself automatically after reset via:
• Internal customer definable One-Time Programmable
memory with up to 16 different configurations
• Standard external I2
C EPROM via separate I2
C Master Port
▪ 1149.1 JTAG Boundary Scan
▪ 10 × 10 mm 72-VFQFPN package

Description
The 8A34002 is a Synchronization Management Unit (SMU) for packet based and physical layer based equipment synchronization. The
8A34002 is a highly integrated device that provides tools to manage timing references, clock sources, and timing paths for IEEE 1588
and Synchronous Ethernet (SyncE) based clocks. The PLL channels can act independently as frequency synthesizers, jitter attenuators,
Digitally Controlled Oscillators (DCO), or Digital Phase Lock Loops (DPLL).
The 8A34002 supports multiple independent timing paths that can each be configured as a DPLL or as a DCO. Input-to-input,
input-to-output, and output-to-output phase skew can all be precisely managed. The device outputs low-jitter clocks that can directly
synchronize interfaces such as 100GBASE-R, 40GBASE-R, 10GBASE-R, 10GBASE-W, and lower-rate Ethernet interfaces; as well as
SONET/SDH and PDH interfaces and IEEE 1588 Time Stamp Units (TSUs).
The internal System APLL must be supplied with a low phase noise reference clock with frequency between 25MHz and 54MHz. The
output of the System APLL is used for clock synthesis by all of the Fractional Output Dividers (FODs) in the device. The System APLL
reference can come from an external crystal oscillator connected to the OSCI pin or from an internal oscillator that uses a crystal
connected between the OSCI and OSCO pins.