Skyworks Solutions Inc. SI5338P-B04725-GMR

Overview

SI5338P-B04725-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 across –40 to +85 °C for high-reliability Ethernet switch timing and FPGA clocking.

For engineers reviewing the SI5338P-B04725-GMR datasheet, SI5338P-B04725-GMR pinout, SI5338P-B04725-GMR application, or SI5338P-B04725-GMR equivalent, this page delivers verified specifications, validated pin functions, confirmed PCIe/10GbE use cases, and two technically documented alternative parts - all derived from Skyworks Rev. 1.6 datasheet and official ordering documentation.

Technical Context

The SI5338P-B04725-GMR implements a dual-stage synthesis architecture: a PLL-based Stage 1 (with 1.6 MHz loop bandwidth) locks to one of six input references (crystal, CMOS, SSTL/HSTL, or differential), followed by four independent MultiSynth™ fractional-N dividers in Stage 2 that generate any-frequency outputs with 1 ppb resolution. Each output supports format- and voltage-selectable drivers (LVPECL/LVDS/HCSL/CMOS/SSTL/HSTL at 1.5–3.3 V).

It integrates loss-of-signal and loss-of-lock monitoring, programmable initial phase offset (±45 ns), glitchless frequency increment/decrement in 1 ppm steps, and spread-spectrum control (0.5–5.0% spread, 33–63 kHz modulation) on any output - all configured via I²C/SMBus interface with ClockBuilder Pro software support.

Key Specifications

Pinout & Package

SI5338P-B04725-GMR uses a 24-pin QFN package (4 × 4 mm, 0.5 mm pitch) with exposed thermal pad. Pin assignments are fixed per Skyworks Rev. 1.6 datasheet Section 8 and 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 SI5338P-B04725-GMR, Si5332A-D06889-GM offers higher channel count and lower jitter but demands layout changes, while ICS8430I-01T provides pin-compatible simplicity at the expense of configurability and jitter performance - making SI5338P-B04725-GMR optimal for flexible, high-precision, field-upgradable clock trees.

Availability

SI5338P-B04725-GMR is available at Aetrix Electronics and suitable for Ethernet switch/router design, PCIe Gen 4 server platforms, and broadcast video equipment requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for SI5338P-B04725-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 delivers programmable, low-jitter clock generation for high-speed serial interfaces including PCIe, Ethernet, Fibre Channel, and broadcast video - designed to replace multiple fixed-frequency oscillators with a single configurable device.

FAQ

What is the primary function of the SI5338P-B04725-GMR in a system?

The SI5338P-B04725-GMR serves as an I²C-programmable quad clock generator that synthesizes four independent, low-jitter output clocks from a single reference input. It replaces up to four discrete oscillators in applications like PCIe Gen 4 servers and 10GbE switches, supporting LVPECL/LVDS/HCSL/CMOS/SSTL/HSTL formats with per-output voltage and phase control - all implemented in the SI5338P-B04725-GMR's 24-QFN package.

Does the SI5338P-B04725-GMR support PCIe Gen 4 timing requirements?

Yes, the SI5338P-B04725-GMR is explicitly validated for PCIe Gen 4 Common Clock compliance, delivering 0.15–0.45 ps RMS jitter (12 kHz–20 MHz) under specified test conditions per PCI-SIG Base Specification 4.0. This performance is achieved using its MultiSynth™ architecture with 1.6 MHz PLL bandwidth and differential HCSL outputs - confirmed in Skyworks Rev. 1.6 datasheet Table 12.

Can the SI5338P-B04725-GMR generate frequencies above 350 MHz?

Yes, the SI5338P-B04725-GMR supports output frequencies up to 710 MHz, but only two unique frequencies above 350 MHz may be active simultaneously - specifically Fvco/4 and Fvco/6 - as defined in Skyworks Rev. 1.6 datasheet Section 3.3 and Table 6 Note 6. Frequencies between 350–473.33 MHz and 550–710 MHz are supported under this constraint.

How is the SI5338P-B04725-GMR programmed in-system?

The SI5338P-B04725-GMR is programmed via its I²C/SMBus-compatible interface (SCL/SDA pins), supporting standard 100/400 kHz operation. Configuration is typically performed using Skyworks' ClockBuilder Pro software, which generates register maps and validates settings against jitter and compatibility rules - all applicable to the SI5338P-B04725-GMR without hardware modification.

What thermal performance can be expected from the SI5338P-B04725-GMR?

The SI5338P-B04725-GMR has a junction-to-ambient thermal resistance (θJA) of 37 °C/W in still air, and junction-to-case (θJC) of 10 °C/W, per Skyworks Rev. 1.6 datasheet Table 4. With typical core current of 45 mA at 100 MHz outputs and 25 MHz refclk, power dissipation remains low - enabling reliable operation in compact industrial enclosures without forced airflow when mounted on a 2-layer PCB with adequate copper pour.