Skyworks Solutions Inc. SI5345A-B05707-GM

Overview

SI5345A-B05707-GM from Skyworks is a 10-channel, any-frequency jitter attenuator/clock multiplier featuring fourth-generation DSPLL™ and MultiSynth™ architectures. It delivers ultra-low 90 fs rms jitter, supports differential input frequencies up to 750 MHz and differential outputs up to 1028 MHz, and operates in free-run, locked, or holdover modes - deployed in OTN transponders and SyncE-compliant carrier Ethernet switches.

For engineers reviewing the SI5345A-B05707-GM datasheet, SI5345A-B05707-GM pinout, SI5345A-B05707-GM application, or SI5345A-B05707-GM equivalent, key selection considerations include its programmable jitter attenuation bandwidth (0.1 Hz–4 kHz), G.8262 EEC Option 1/2 compliance, I²C/SPI configurability with on-chip NVM, and support for LVDS/LVPECL/LVCMOS/CML/HCSL output formats with independent supply pins.

Technical Context

The SI5345A-B05707-GM implements a digitally controlled DSPLL with fractional input dividers (P) enabling hitless switching between fractionally related input clocks, and high-performance MultiSynth dividers (N) generating integer/fractional output frequencies. Its loop filter is fully integrated, eliminating external passive components and noise coupling risks.

It supports automatic/manual input clock selection with status monitoring (LOS/OOF/LOL), glitchless on-the-fly output frequency changes, DCO mode with 0.001 ppb step size, and zero-delay mode when IN3 is configured as FB_IN. Core voltage is 1.8 V ±5%, analog supply is 3.3 V ±5%, and output supplies are independently configurable at 3.3 V, 2.5 V, or 1.8 V.

Key Specifications

Pinout & Package

The SI5345A-B05707-GM is housed in a 64-pin QFN package measuring 9 mm × 9 mm with exposed thermal pad, RoHS-6 compliant and rated for –40 °C to +85 °C operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar jitter attenuator applications.

Compared with Si5345A-D-GM and LTC6955IUKG-1#PBF, the SI5345A-B05707-GM provides factory-programmed readiness, full 10-output flexibility, and telecom-grade holdover/resilience - making it optimal for production-deployed OTN and SyncE systems requiring zero-configuration reliability.

Availability

SI5345A-B05707-GM is available at Aetrix Electronics and suitable for OTN transponders, SyncE carrier switches, and broadcast video infrastructure requiring stable component supply, long-term lifecycle assurance, and guaranteed traceable sourcing.

Supply support for SI5345A-B05707-GM includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Skyworks Solutions is a global semiconductor company specializing in analog and mixed-signal connectivity solutions for wireless, broadband, automotive, and industrial markets.

The Si5345 family is designed as high-performance jitter attenuators for telecom and datacom infrastructure, targeting applications demanding G.8262 compliance, multi-gigabit SerDes clocking, and resilient holdover operation - with SI5345A-B05707-GM representing a factory-preprogrammed variant optimized for immediate deployment.

FAQ

What is the primary function of the SI5345A-B05707-GM in a telecom timing architecture?

The SI5345A-B05707-GM functions as a jitter-attenuating clock multiplier that cleans and regenerates timing signals from noisy or unstable references. In telecom systems, it locks to an incoming SyncE or SONET clock, attenuates phase jitter using its digitally programmable DSPLL, and distributes low-jitter copies across up to 10 outputs - ensuring signal integrity for high-speed SerDes and framers. Its holdover capability maintains timing during input loss, making SI5345A-B05707-GM essential for carrier-grade reliability.

Does the SI5345A-B05707-GM require external loop filter components?

No, the SI5345A-B05707-GM integrates the entire DSPLL loop filter on-die, eliminating discrete resistors and capacitors. This integration removes sensitivity to PCB layout parasitics and external noise coupling, directly contributing to its specified 90 fs rms jitter performance. The absence of external filter components simplifies board design, improves repeatability across manufacturing lots, and enhances long-term stability - all confirmed in the Si5345/44/42 Rev D datasheet section 3.2 and Figure 6.1.

How does the SI5345A-B05707-GM handle input clock failures in a redundant timing system?

Upon input clock failure, the SI5345A-B05707-GM automatically enters holdover mode using up to 120 seconds of stored frequency history to compute an averaged holdover frequency. This minimizes phase transients at the outputs. The holdover stability depends solely on the XA/XB crystal (25–54 MHz), and the device exits holdover glitchlessly when a valid input returns. These behaviors - including programmable holdover window and ramped exit - are inherent to SI5345A-B05707-GM's DSPLL architecture per datasheet sections 3.4.5 and 3.7.4.

Can the SI5345A-B05707-GM generate different output frequencies simultaneously?

Yes, the SI5345A-B05707-GM supports independent frequency synthesis on all 10 outputs via its MultiSynth architecture. Each output can be assigned a unique frequency derived from the same or different input sources, with integer or fractional division. Output formats (LVDS, LVPECL, LVCMOS, CML, HCSL), amplitudes, and common-mode voltages are individually programmable - enabling SI5345A-B05707-GM to serve heterogeneous clock domains such as SerDes, memory controllers, and management processors on a single board.

Is the SI5345A-B05707-GM pin-compatible with other Si5345 variants like Si5345A-D-GM?

Yes, the SI5345A-B05707-GM shares identical 64-QFN 9×9 mm packaging and pinout with all Si5345A-D-GM variants, including mechanical footprint, power, ground, I/O, and control pin assignments. Differences lie exclusively in factory-programmed NVM content - SI5345A-B05707-GM contains a specific preconfigured frequency plan, while Si5345A-D-GM ships unprogrammed. No PCB or schematic changes are needed when substituting within the same Si5345A prefix family.