Skyworks Solutions Inc. SI5345A-B05576-GM

Overview

SI5345A-B05576-GM from Skyworks is a 10-channel, any-frequency jitter attenuator/clock multiplier IC with fourth-generation DSPLL™ and MultiSynth™ architecture. 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 - enabling precise clock synthesis for SyncE-compliant 100 GbE line cards.

For engineers reviewing the SI5345A-B05576-GM datasheet, SI5345A-B05576-GM pinout, SI5345A-B05576-GM application, or SI5345A-B05576-GM equivalent, key selection considerations include its programmable jitter attenuation bandwidth (0.1 Hz–4 kHz), G.8262 EEC Option 1/2 compliance, 64-QFN 9×9 mm package, I²C/SPI configurability, and factory preprogrammed NVM configuration.

Technical Context

The SI5345A-B05576-GM implements a digitally controlled DSPLL with fractional input dividers (P) and MultiSynth output dividers (N/R) to enable hitless switching between fractionally related inputs and glitchless on-the-fly frequency changes. Its loop filter is fully integrated, eliminating external components and noise coupling risks.

It supports three operational modes - freerun (crystal-referenced), locked (phase- and frequency-locked to input), and holdover (averaged historical frequency retention up to 120 s) - with programmable ramped holdover exit and automatic/manual input clock selection across four inputs (IN0–IN3).

Key Specifications

Pinout & Package

The SI5345A-B05576-GM is housed in a 64-pin QFN package (9 mm × 9 mm, 0.5 mm pitch) with exposed thermal pad. Pin functions are defined per Skyworks Si5345 Rev D datasheet Section 9 (Pin Descriptions).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SI5345A-B05576-GM, Si5345B-D-GM trades output bandwidth and synthesis flexibility for lower cost, while LMK04832 requires external loop components and delivers slightly higher jitter - making SI5345A-B05576-GM optimal for compact, high-performance SyncE and OTN timing where integrated crystal support and 1028 MHz capability are essential.

Availability

SI5345A-B05576-GM is available at Aetrix Electronics and suitable for 100GbE line cards, OTN transponders, and broadcast video infrastructure requiring stable component supply, long-term lifecycle assurance, and factory-programmed configuration traceability.

Supply support for SI5345A-B05576-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 communications, automotive, and industrial markets.

The SI5345A-B05576-GM belongs to Skyworks' Si5345 family of jitter-attenuating clock multipliers, engineered specifically for carrier-class synchronization in OTN, SyncE, and high-speed data center interconnect applications.

FAQ

What is the primary function of the SI5345A-B05576-GM in a telecom timing architecture?

The SI5345A-B05576-GM serves as a jitter-attenuating clock multiplier that cleans and regenerates high-frequency reference clocks for SerDes, PHYs, and framer ICs. It locks to degraded input clocks (e.g., from fiber links), suppresses accumulated jitter using its DSPLL, and generates multiple low-jitter outputs - enabling SI5345A-B05576-GM to meet ITU-T G.8262 EEC Option 1/2 and GR-1244-CORE requirements in 100GbE and OTN systems.

Does the SI5345A-B05576-GM require an external crystal, and what frequency range is supported?

Yes, the SI5345A-B05576-GM requires an external fundamental-mode crystal connected to XA/XB pins. It supports crystals from 25 MHz to 54 MHz, with 48–54 MHz recommended for optimal jitter performance. Internal load capacitors eliminate the need for external C_L components, simplifying layout and improving noise immunity - a key design advantage of the SI5345A-B05576-GM over competing jitter cleaners.

How does the SI5345A-B05576-GM handle input clock failures in mission-critical networks?

Upon input clock failure, the SI5345A-B05576-GM automatically enters holdover mode using up to 120 seconds of stored historical frequency data to compute an averaged holdover frequency. This minimizes phase disturbance at outputs. The SI5345A-B05576-GM then maintains timing accuracy based on its crystal reference, with drift governed by crystal stability - ensuring continuous operation during GPS/GNSS or upstream link outages in SyncE deployments.

Can the SI5345A-B05576-GM generate different output formats simultaneously, and how is this configured?

Yes, the SI5345A-B05576-GM supports simultaneous LVDS, LVPECL, CML, HCSL, and LVCMOS outputs across its 10 channels. Each output has independent format, amplitude, common-mode voltage, and termination control via register settings. Configuration is performed using ClockBuilder Pro™ software or direct I²C/SPI writes - allowing SI5345A-B05576-GM to drive diverse SerDes, FPGA, and ASIC interfaces from a single device.

Is the SI5345A-B05576-GM pin-compatible with other devices in the Si5345 family?

No - the SI5345A-B05576-GM shares the same 64-QFN 9×9 mm package and core pinout as all Si5345 variants (e.g., Si5345B-D-GM), but it is not pin-compatible with Si5344 or Si5342 due to differing pin counts (44-QFN) and functional allocations. However, SI5345A-B05576-GM retains full register-level compatibility within the Si5345 family, enabling firmware reuse across A/B/C/D variants when output frequency and synthesis mode requirements align.