Skyworks Solutions Inc. SI5338Q-B04258-GMR

Overview

SI5338Q-B04258-GMR from Skyworks Solutions is an I²C-programmable quad clock generator with four independent differential output drivers, 0.7 ps RMS typical phase jitter, PCIe Gen 1–4 Common Clock and Gen 3 SRNS compliance, and support for LVPECL/LVDS/HCSL/CMOS/SSTL/HSTL output formats across 0.16–710 MHz. It replaces up to four crystal oscillators in high-speed serial interface timing applications.

For engineers reviewing the SI5338Q-B04258-GMR datasheet, SI5338Q-B04258-GMR pinout, SI5338Q-B04258-GMR application, or SI5338Q-B04258-GMR equivalent, key selection criteria include its MultiSynth™ fractional-N synthesis architecture, independent per-output voltage (1.5/1.8/2.5/3.3 V), ±20 ps phase step resolution, and 4×4 mm 24-QFN package with I²C/SMBus configuration.

Technical Context

The SI5338Q-B04258-GMR implements a two-stage PLL architecture: a high-stability integer-N Phase-Locked Loop (PLL) for reference conditioning followed by four independent MultiSynth™ fractional-N synthesis blocks-one per output-enabling true zero-ppm frequency accuracy and glitchless frequency increment/decrement in 1 ppm steps. Each output supports programmable initial phase offset (±45 ns) and fine phase adjustment (<20 ps steps).

It accepts six input references-including external crystal (8–30 MHz), CMOS (5–200 MHz), SSTL/HSTL (5–350 MHz), and differential (5–710 MHz)-and delivers configurable spread spectrum (0.5–5.0% spread, 33–63 kHz modulation rate) on any output. Loss-of-lock and loss-of-signal alarms provide real-time status monitoring via the INTR pin.

Key Specifications

Pinout & Package

SI5338Q-B04258-GMR is housed in a 24-lead, 4 × 4 mm QFN package with exposed thermal pad. Pin assignments are fixed per the Si5338 family and validated for this variant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with Si5332A-D06581-GM and ICS853S01IAGLF, the SI5338Q-B04258-GMR uniquely balances field-programmability, industrial temperature range, mixed-voltage outputs, and PCIe Gen 4 compliance in a compact 4×4 mm QFN-making it optimal for reconfigurable embedded systems where clock requirements evolve post-deployment.

Availability

SI5338Q-B04258-GMR is available at Aetrix Electronics and suitable for PCIe Gen 4 switch timing, Ethernet switch clocking, and broadcast video sync generator applications requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for SI5338Q-B04258-GMR 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 for infrastructure, automotive, and mobile markets.

The Si5338 product line was designed to replace multiple discrete oscillators in high-speed digital systems, delivering programmable, low-jitter clock synthesis for PCIe, Ethernet, broadcast, and FPGA-based platforms.

FAQ

What is the primary function of the SI5338Q-B04258-GMR?

The SI5338Q-B04258-GMR is an I²C-programmable quad clock generator that synthesizes four independent, low-jitter output clocks from a single input reference. Its core function is to replace up to four discrete crystal oscillators while enabling precise frequency, phase, voltage, and format configuration per output-critical for PCIe Gen 4, Ethernet, and FPGA timing systems.

Does the SI5338Q-B04258-GMR support PCIe Gen 4 timing requirements?

Yes, the SI5338Q-B04258-GMR meets PCIe Gen 4 Common Clock jitter specifications with 0.15–0.45 ps RMS jitter (10 kHz–50 MHz) and supports Gen 3 SRNS mode. It achieves this using its dual-loop architecture, optimized MultiSynth™ synthesis, and configurable PLL bandwidth (2–5 MHz), validated per PCI-SIG requirements.

Can the SI5338Q-B04258-GMR generate different output voltages simultaneously?

Yes-the SI5338Q-B04258-GMR supports independent output buffer supply rails (VDDO0–VDDO3), allowing simultaneous 1.5 V, 1.8 V, 2.5 V, and 3.3 V outputs. This enables direct interfacing with mixed-voltage FPGAs, ASICs, and SerDes blocks without external level shifters or regulators.

How is the SI5338Q-B04258-GMR programmed and configured?

The SI5338Q-B04258-GMR is programmed via its I²C/SMBus-compatible serial interface using Skyworks' ClockBuilder Pro software. Configuration includes output frequency, format, voltage, phase offset, spread spectrum, and status monitoring-all stored in on-chip OTP memory. Factory pre-programming is also supported.

What package type and thermal characteristics does the SI5338Q-B04258-GMR have?

The SI5338Q-B04258-GMR uses a 24-pin QFN package measuring 4 × 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, enabling reliable operation at full load across –40 °C to +85 °C ambient without forced airflow.