Skyworks Solutions Inc. SI5338C-B05629-GM

Overview

SI5338C-B05629-GM from Skyworks Solutions is an I²C-programmable quad clock generator with four independently configurable differential or single-ended outputs, 0.7 ps RMS typical phase jitter, PCIe Gen 1–4 and SRNS compliance, and MultiSynth™ frequency synthesis supporting 0.16–710 MHz output ranges across LVPECL/LVDS/HCSL/CMOS/SSTL/HSTL formats. It replaces up to four crystal oscillators in FPGA, processor, and Ethernet switch timing systems.

For engineers reviewing the SI5338C-B05629-GM datasheet, SI5338C-B05629-GM pinout, SI5338C-B05629-GM application, or SI5338C-B05629-GM equivalent, key selection considerations include its 24-QFN package, I²C/SMBus programmability, independent per-output voltage (1.5/1.8/2.5/3.3 V), spread-spectrum capability (0.5–5.0% at 33–63 kHz), and zero-ppm synthesis accuracy across all four outputs.

Technical Context

The SI5338C-B05629-GM implements a two-stage PLL architecture: a high-stability reference stage followed by four independent MultiSynth™ fractional-N synthesis blocks, each feeding a configurable output driver. Its input flexibility supports external crystals (8–30 MHz), CMOS (5–200 MHz), SSTL/HSTL (5–350 MHz), and differential clocks (5–710 MHz).

Each output driver supports independent format selection, voltage supply (VDDOx), phase offset (±45 ns, <20 ps step), and frequency increment/decrement (1 ppm steps, glitchless). The device includes loss-of-lock and loss-of-signal alarms, external feedback for zero-delay mode, and I²C register access to all configuration and status bits.

Key Specifications

Pinout & Package

SI5338C-B05629-GM uses a 24-lead, 4 × 4 mm QFN package with exposed thermal pad. Pin functions are defined per Skyworks Rev. 1.6 datasheet (pages 33–37) and validated for this specific variant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with Si5338A-B-GM and ICS8430I-01LG, SI5338C-B05629-GM uniquely combines field-programmable MultiSynth™ synthesis, per-output voltage/format control, and PCIe Gen 4 SRNS compliance - making it the only option for flexible, high-performance timing in evolving compute and networking platforms.

Availability

SI5338C-B05629-GM is available at Aetrix Electronics and suitable for FPGA clocking, PCIe Gen 4 infrastructure, and broadcast video timing requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for SI5338C-B05629-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 power management ICs.

The Si5338 product line delivers programmable, low-jitter clock generation for high-speed digital systems including data centers, telecom infrastructure, and broadcast equipment - designed to replace multiple discrete oscillators with a single configurable device.

FAQ

What is the primary function of the SI5338C-B05629-GM in a timing architecture?

The SI5338C-B05629-GM serves as a fully programmable quad clock generator that synthesizes four independent, low-jitter output clocks from a single reference input. Its core function is to replace multiple fixed-frequency crystal oscillators while enabling precise frequency, phase, format, and voltage control per output - directly implemented in the SI5338C-B05629-GM's MultiSynth™ architecture and I²C-configurable registers.

Does the SI5338C-B05629-GM support PCIe Gen 4 Common Clock mode?

Yes, the SI5338C-B05629-GM meets PCIe Gen 4 Common Clock jitter specifications with ≤0.45 ps RMS (10 kHz–50 MHz) when configured per Skyworks AN562 guidelines. This performance is verified using the Skyworks PCIe Clock Jitter Tool and applies to 100 MHz HCSL outputs with appropriate PLL bandwidth and CDR settings - a confirmed specification for the SI5338C-B05629-GM.

Can the SI5338C-B05629-GM generate different output voltages simultaneously?

Yes, the SI5338C-B05629-GM supports independent output supply voltages: VDDO0 through VDDO3 can each be set to 1.5 V, 1.8 V, 2.5 V, or 3.3 V. This allows simultaneous LVDS (2.5 V), HCSL (1.8 V), and CMOS (3.3 V) outputs on the same device - a confirmed capability documented in the "Output Stage" section (page 21) and Table 6 of the SI5338C-B05629-GM datasheet.

What reference inputs does the SI5338C-B05629-GM accept?

The SI5338C-B05629-GM accepts five reference types: 8–30 MHz crystal (differential), 5–200 MHz CMOS (single-ended), 5–350 MHz SSTL/HSTL (single-ended), and 5–710 MHz differential (AC-coupled). All are supported natively by the SI5338C-B05629-GM's input stage circuitry and validated in Tables 6 and 8–11 of the official Skyworks datasheet.

Is ClockBuilder Pro software required to configure the SI5338C-B05629-GM?

No - ClockBuilder Pro is optional but strongly recommended. The SI5338C-B05629-GM is fully controllable via standard I²C commands to its internal register map; however, ClockBuilder Pro automates configuration, validates jitter performance, generates initialization code, and exports .cmm files - significantly reducing development time for the SI5338C-B05629-GM in complex multi-output scenarios.