Skyworks Solutions Inc. SI5338C-B04171-GM

Overview

SI5338C-B04171-GM from Skyworks Solutions is a quad-output, I²C-programmable clock generator with MultiSynth™ frequency synthesis. It delivers four independent, any-frequency clocks (0.16–710 MHz) with 0.7 ps RMS typical phase jitter, PCIe Gen 1–4 compliance, and support for LVPECL/LVDS/HCSL/CMOS/SSTL/HSTL output formats. It replaces up to four crystal oscillators in FPGA, processor, and Ethernet switch timing applications.

For engineers reviewing the SI5338C-B04171-GM datasheet, SI5338C-B04171-GM pinout, SI5338C-B04171-GM application, or SI5338C-B04171-GM equivalent, key selection criteria include differential output jitter performance (0.7 ps RMS), PCIe Gen 4 Common Clock compliance, independent per-output voltage control (1.5/1.8/2.5/3.3 V), 4×4 mm 24-QFN package, and I²C/SMBus programmability with ClockBuilder Pro software support.

Technical Context

The SI5338C-B04171-GM implements a two-stage PLL architecture: a high-stability reference PLL (Stage 1) locks to an external crystal (8–30 MHz) or clock input (5–710 MHz), followed by four independent MultiSynth™ fractional-N synthesizers (Stage 2) generating outputs with zero-ppm accuracy. Each output driver supports configurable format, voltage, and spread-spectrum modulation.

It features loss-of-lock and loss-of-signal monitoring, independent 20-ps phase increment/decrement per output, and glitchless frequency adjustment in 1 ppm steps. The device operates across –40 to +85 °C with core supply options of 1.8 V, 2.5 V, or 3.3 V and output buffer supplies from 1.4 V to 3.63 V.

Key Specifications

Pinout & Package

SI5338C-B04171-GM uses a 24-lead QFN package (4 mm × 4 mm, 0.5 mm pitch) with exposed thermal pad. Pin assignments are fixed per Skyworks Si5338 family specification.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad-output programmable clock generator applications.

Compared with Si5338A-B04171-GM, the SI5338C-B04171-GM offers full I²C reprogrammability and blank OTP for custom clock trees, while LMK04832RHAR provides superior phase noise for RF but requires external reference and adds layout complexity.

Availability

SI5338C-B04171-GM is available at Aetrix Electronics and suitable for FPGA clocking, PCIe timing, and Ethernet switch applications requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for SI5338C-B04171-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 Si5338 product line delivers highly configurable, low-jitter clock generation for high-speed digital systems where timing precision, flexibility, and integration reduce bill-of-materials and board space.

FAQ

What is the primary function of the SI5338C-B04171-GM?

The SI5338C-B04171-GM is an I²C-programmable quad clock generator using Skyworks' MultiSynth™ technology to synthesize four independent, any-frequency output clocks (0.16–710 MHz) with 0.7 ps RMS typical phase jitter. It serves as a flexible, low-jitter timing solution for FPGA, processor, PCIe, and Ethernet applications - replacing up to four discrete oscillators while supporting mixed signal formats and voltages.

Does the SI5338C-B04171-GM support PCIe Gen 4 timing requirements?

Yes, the SI5338C-B04171-GM meets PCIe Gen 4 Common Clock jitter specifications (0.15–0.45 ps RMS) when configured per Skyworks AN562 guidelines: 100 MHz HCSL output, PLL bandwidth of 2–4 MHz or 2–5 MHz, and CDR = 10 MHz. This compliance is verified using the Skyworks PCIe Clock Jitter Tool and Intel Clock Jitter Tool v1.6.4.

Can the SI5338C-B04171-GM operate with a crystal reference?

Yes, the SI5338C-B04171-GM supports external crystals from 8 to 30 MHz on its dedicated crystal input pins (IN1/IN2). It integrates on-chip load capacitance (11–13 pF supported, 17–19 pF recommended) and accommodates ESR up to 300 Ω, enabling direct crystal connection without external tuning components.

How is the SI5338C-B04171-GM programmed and configured?

The SI5338C-B04171-GM is programmed via its I²C/SMBus-compatible interface using Skyworks' ClockBuilder Pro software. This GUI-based tool enables full register configuration, frequency synthesis setup, output format/voltage assignment, spread-spectrum settings, and phase/offset tuning - then generates a custom configuration file for one-time OTP programming or runtime I²C loading.

What package type and thermal characteristics does the SI5338C-B04171-GM have?

The SI5338C-B04171-GM uses a 24-lead QFN package measuring 4 mm × 4 mm with 0.5 mm pitch and an exposed thermal pad. Its thermal resistance is θJA = 37 °C/W (still air) and θJC = 10 °C/W, supporting reliable operation from –40 to +85 °C with typical core current draw of 45 mA at 100 MHz on all outputs and 25 MHz reference.