Skyworks Solutions Inc. SI5338A-B05923-GMR

Overview

SI5338A-B05923-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. It replaces up to four crystal oscillators in Ethernet switch/router, PCIe, and FPGA clocking systems.

For engineers reviewing the SI5338A-B05923-GMR datasheet, SI5338A-B05923-GMR pinout, SI5338A-B05923-GMR application, or SI5338A-B05923-GMR equivalent, key selection criteria include its MultiSynth™-based any-frequency synthesis (0.16–710 MHz), independent output voltage per driver (1.5/1.8/2.5/3.3 V), and support for LVPECL/LVDS/HCSL/CMOS/SSTL/HSTL formats.

Technical Context

The SI5338A-B05923-GMR implements a two-stage PLL architecture: a high-stability reference stage followed by four independent MultiSynth™ fractional-N synthesizers, each driving one output pair. Input flexibility includes external crystal (8–30 MHz), CMOS (5–200 MHz), SSTL/HSTL (5–350 MHz), or differential (5–710 MHz) references.

Each output supports programmable frequency increment/decrement in 1 ppm steps, phase adjustment in <20 ps steps, and spread-spectrum modulation (0.5–5.0% spread, 33–63 kHz rate). The device operates from a single 1.8/2.5/3.3 V core supply and features loss-of-lock and loss-of-signal alarms via the INTR pin.

Key Specifications

Pinout & Package

SI5338A-B05923-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 SI5338A-B05923-GMR, Si5338A-B05922-GM requires post-manufacturing configuration for PCIe Gen 4, while LMK04832RHAT adds jitter-cleaning capability at higher cost and power - making SI5338A-B05923-GMR optimal for PCIe- and Ethernet-focused designs needing certified, ready-to-deploy timing.

Availability

SI5338A-B05923-GMR is available at Aetrix Electronics and suitable for Ethernet switch/router, PCIe Gen 1–4, and broadcast video timing applications requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for SI5338A-B05923-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 precision analog ICs.

The Si5338 product line delivers programmable, low-jitter clock generation for high-speed digital systems - designed specifically for PCIe, Ethernet, telecom, and broadcast infrastructure where frequency flexibility and jitter performance are critical.

FAQ

What is the default factory configuration of the SI5338A-B05923-GMR?

The SI5338A-B05923-GMR ships with a pre-programmed configuration optimized for PCIe Gen 4 Common Clock and SRNS compliance, including 100 MHz HCSL outputs, 2–4 MHz PLL bandwidth, and default spread-spectrum settings. This eliminates need for initial I²C programming in PCIe reference designs.

Does the SI5338A-B05923-GMR support external feedback for zero-delay mode?

Yes, the SI5338A-B05923-GMR supports external feedback mode via the fb pin, enabling zero-delay operation where output phase is locked to an external system clock - useful in synchronous backplane timing and deterministic latency applications.

Can the SI5338A-B05923-GMR generate frequencies above 350 MHz on all four outputs simultaneously?

No. The SI5338A-B05923-GMR can output only two unique frequencies above 350 MHz simultaneously - specifically Fvco/4 and Fvco/6 - due to VCO frequency constraints. Other outputs must be ≤350 MHz or integer-related to those high-frequency outputs.

How does the SI5338A-B05923-GMR handle loss-of-signal detection?

The SI5338A-B05923-GMR detects loss of signal on any input within 2.6–5 µs and asserts the INTR pin. Release time is 0.01–1 µs. Detection is active for all input types (differential, CMOS, SSTL) except in PLL bypass mode below 5 MHz.

Is ClockBuilder Pro required to configure the SI5338A-B05923-GMR?

No - the SI5338A-B05923-GMR operates immediately with its factory-programmed configuration. ClockBuilder Pro is optional for custom frequency plans, phase alignment, spread-spectrum tuning, or exporting register maps; I²C writes can also be performed directly in-system.