Skyworks Solutions Inc. SI5338F-B04076-GMR

Overview

SI5338F-B04076-GMR 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 Common Clock and Gen 3 SRNS compliance, and operation from 1.8/2.5/3.3 V core supply in a 4 × 4 mm 24-QFN package. It replaces up to four crystal oscillators in high-speed serial interface timing applications.

For engineers reviewing the SI5338F-B04076-GMR datasheet, SI5338F-B04076-GMR pinout, SI5338F-B04076-GMR application, or SI5338F-B04076-GMR equivalent, key selection considerations include its MultiSynth™-based any-frequency synthesis (0.16–710 MHz per output), independent output voltage per driver (1.5–3.3 V), <20 ps phase step resolution, and support for PCIe, Ethernet, and FPGA clocking with zero-ppm frequency accuracy.

Technical Context

The SI5338F-B04076-GMR implements a two-stage PLL architecture: a high-stability reference stage (with crystal or external clock input) followed by four independent MultiSynth™ fractional-N synthesis paths, each feeding a configurable output driver. Its digital control logic supports real-time frequency increment/decrement in 1 ppm steps and phase adjustment in <20 ps increments via I²C or dedicated pins.

Input flexibility includes differential (5–710 MHz), CMOS (5–200 MHz), SSTL/HSTL (5–350 MHz), or 8–30 MHz crystal references; outputs support LVPECL/LVDS/HCSL/CMOS/SSTL/HSTL formats across overlapping frequency ranges, with independent VDDO per bank (1.5–3.3 V) and programmable spread spectrum on any output (0.5–5.0% spread, 33–63 kHz modulation).

Key Specifications

Pinout & Package

SI5338F-B04076-GMR is housed in a 4 × 4 mm, 24-pin QFN package with exposed thermal pad. Pin assignments are fixed per the Si5338 family: six input pins (IN1–IN6), eight clock output terminals (CLK0A/B through CLK3A/B), four VDDO supplies (VDDO0–VDDO3), three power rails (VDD, GND, RSVD_GND), and I²C/INTR control pins (SCL, SDA, INTR).

Key Features

Applications

Equivalent & Alternatives

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

Compared with Si5332A-D06189-GM and ICS853S01AGI-01LF, the SI5338F-B04076-GMR uniquely balances field-programmability, PCIe Gen 4 compliance, and compact 4 × 4 mm footprint-making it optimal for space-constrained, multi-standard timing in networking and compute platforms.

Availability

SI5338F-B04076-GMR is available at Aetrix Electronics and suitable for PCIe Gen 4 switch timing, Ethernet switching/routing, and FPGA clocking requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for SI5338F-B04076-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 leader in analog and mixed-signal semiconductors, specializing in RF, timing, and connectivity solutions for infrastructure, automotive, and mobile markets.

The Si5338 product line delivers programmable, low-jitter clock generation for high-speed serial interfaces-including PCIe, Ethernet, and Fibre Channel-enabling flexible, future-proof timing architectures in next-generation computing and communications systems.

FAQ

What is the primary function of the SI5338F-B04076-GMR?

The SI5338F-B04076-GMR is an I²C-programmable quad clock generator that synthesizes up to four independent, low-jitter output frequencies from a single input reference. It replaces multiple crystal oscillators in systems requiring precise, flexible timing-such as PCIe Gen 4 switches, Ethernet routers, and FPGA-based platforms-while maintaining 0.7 ps RMS typical phase jitter and zero-ppm frequency accuracy.

Does the SI5338F-B04076-GMR support PCIe Gen 4 timing requirements?

Yes, the SI5338F-B04076-GMR is explicitly validated for PCIe Gen 4 common clock mode with ≤0.45 ps RMS jitter (12 kHz–20 MHz) and meets Gen 3 SRNS specifications. Its MultiSynth™ architecture, low-noise PLL design, and differential output drivers ensure compliance when configured per Skyworks' AN562 guidelines and using recommended layout practices.

Can the SI5338F-B04076-GMR generate frequencies above 350 MHz?

Yes-the SI5338F-B04076-GMR supports output frequencies up to 710 MHz. However, only two unique frequencies above 350 MHz can be generated simultaneously (Fvco/4 and Fvco/6). Frequencies between 350–473.33 MHz and 550–710 MHz are supported depending on VCO operating range and divider settings.

How is the SI5338F-B04076-GMR programmed in-system?

The SI5338F-B04076-GMR is programmed via its I²C/SMBus-compatible serial interface using Skyworks' ClockBuilder Pro software. This GUI-based tool generates configuration files and registers maps, enabling full customization of output frequencies, formats, voltages, spread spectrum, and alarm thresholds without custom firmware development.

What package type and pin count does the SI5338F-B04076-GMR use?

The SI5338F-B04076-GMR uses a 4 × 4 mm, 24-pin QFN package with an exposed thermal pad. It features six input pins (IN1–IN6), eight differential clock outputs (CLK0A/B through CLK3A/B), four independent VDDO supplies (VDDO0–VDDO3), and standard I²C control pins (SCL, SDA, INTR), matching the pinout defined in the Si5338 family datasheet Rev. 1.6.