Skyworks Solutions Inc. SI5338C-B04167-GM

Overview

SI5338C-B04167-GM from Skyworks Solutions is a quad-output, I²C-programmable clock generator with MultiSynth™ frequency synthesis, delivering four independent low-jitter clocks (0.7 ps RMS typical phase jitter), supporting LVPECL/LVDS/HCSL/CMOS/SSTL/HSTL outputs up to 710 MHz, and operating from 1.8/2.5/3.3 V core supply in a 4 × 4 mm 24-QFN package. It serves as a PCIe Gen 1–4 common-clock source and replaces multiple crystal oscillators in FPGA, processor, and Ethernet switch timing systems.

For engineers reviewing the SI5338C-B04167-GM datasheet, SI5338C-B04167-GM pinout, SI5338C-B04167-GM application, or SI5338C-B04167-GM equivalent, key selection criteria include PCIe Gen 4 SRNS compliance, independent per-output voltage configuration (1.5–3.3 V), 1 ppm frequency increment/decrement capability, <20 ps phase step resolution, and spread-spectrum support (0.5–5.0% at 33–63 kHz).

Technical Context

The SI5338C-B04167-GM implements a two-stage PLL architecture: a high-stability reference stage followed by four independent MultiSynth™ fractional-N synthesizers, each driving a configurable output buffer. Its input flexibility includes differential (5–710 MHz), CMOS (5–200 MHz), SSTL/HSTL (5–350 MHz), or 8–30 MHz crystal references.

Each output supports independent format selection (LVPECL, LVDS, HCSL, CMOS, SSTL, HSTL), voltage (1.5/1.8/2.5/3.3 V), phase offset (±45 ns), and spread-spectrum modulation (5–350 MHz, 0.5–5.0%, 33–63 kHz), with loss-of-lock and loss-of-signal alarms for system monitoring.

Key Specifications

Pinout & Package

SI5338C-B04167-GM uses a 24-lead QFN package (4 × 4 mm, 0.5 mm pitch) with exposed thermal pad. Pin assignments are fixed across Si5338 family variants per Skyworks Rev. 1.6 datasheet Figure 1 (Top View).

Key Features

Applications

Equivalent & Alternatives

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

Compared with Si5338A-B04167-GM, the SI5338C-B04167-GM offers identical hardware functionality but distinct factory NVM defaults-enabling faster bring-up for specific clock trees. Against LMK04832, SI5338C-B04167-GM provides superior integration density, lower power, and finer-grained per-output configurability at the expense of dual-PLL architectural flexibility.

Availability

SI5338C-B04167-GM is available at Aetrix Electronics and suitable for PCIe Gen 4 server platforms, 10/25GbE switch timing, and broadcast video processing requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for SI5338C-B04167-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, with leadership in RF, timing, and precision analog ICs for infrastructure, automotive, and mobile markets.

The Si5338 product line delivers highly configurable, low-jitter clock generation for high-speed serial interfaces-including PCIe, Ethernet, Fibre Channel, and broadcast video-designed to replace multiple discrete oscillators while enabling flexible, software-defined timing architectures.

FAQ

What is the primary function of the SI5338C-B04167-GM in a PCIe Gen 4 system?

The SI5338C-B04167-GM serves as a common-clock source compliant with PCIe Gen 4 Separate Reference No Spread (SRNS) specifications, delivering four low-jitter (≤0.32 ps RMS) outputs that meet the stringent phase noise and jitter requirements for root complex and endpoint synchronization. Its programmable MultiSynth™ architecture ensures zero-ppm accuracy across all outputs without external dividers or filters.

Does the SI5338C-B04167-GM support spread-spectrum clocking on all outputs?

Yes, the SI5338C-B04167-GM supports independent spread-spectrum modulation on any output, with configurable parameters including spread percentage (0.5–5.0%), modulation rate (33–63 kHz), and center frequency (5–350 MHz). This feature is implemented per-output via dedicated registers and does not require shared resources or compromise other outputs' performance.

How does the SI5338C-B04167-GM handle different output voltage levels simultaneously?

The SI5338C-B04167-GM provides four independent VDDOx supplies (VDDO0–VDDO3), each configurable from 1.4 V to 3.63 V. This allows simultaneous LVDS (2.5 V), HCSL (1.8 V), and CMOS (3.3 V) outputs on the same device-enabling direct interfacing with mixed-voltage ASICs, FPGAs, and SerDes without level-shifting components.

Can the SI5338C-B04167-GM operate without an external crystal?

Yes, the SI5338C-B04167-GM supports multiple reference sources: external 8–30 MHz crystals, differential AC-coupled inputs (5–710 MHz), single-ended CMOS inputs (5–200 MHz), and SSTL/HSTL inputs (5–350 MHz). Crystal operation is optional; the device functions fully in free-running or buffered modes using any supported reference.

What tools are required to configure the SI5338C-B04167-GM?

Configuration of the SI5338C-B04167-GM is performed using Skyworks' ClockBuilder Pro software, which generates custom configuration files (.cbs) and supports I²C programming via USB-to-I²C adapters or embedded host controllers. The SI5338C-B04167-GM also supports pin-strapped default states and nonvolatile memory (OTP) for unattended boot operation.