Skyworks Solutions Inc. SI5338A-B05495-GMR

Overview

SI5338A-B05495-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 and SRNS compliance, and operation across –40 to +85 °C in a 4 × 4 mm 24-QFN package. It replaces up to four crystal oscillators in Ethernet switch/router, FPGA clocking, and PCIe timing applications.

For engineers reviewing the SI5338A-B05495-GMR datasheet, SI5338A-B05495-GMR pinout, SI5338A-B05495-GMR application, or SI5338A-B05495-GMR equivalent, key selection criteria include its MultiSynth™ any-frequency synthesis (0.16–710 MHz per output), independent output voltage support (1.5/1.8/2.5/3.3 V), spread-spectrum capability (0.5–5.0% down-spread), and I²C/SMBus programmability with ClockBuilder Pro software integration.

Technical Context

The SI5338A-B05495-GMR implements a two-stage PLL architecture: a high-stability reference stage (with crystal or external clock input) feeding a fractional-N MultiSynth™ synthesis stage per output. Each of the four outputs features independent frequency, format (LVPECL/LVDS/HCSL/CMOS/SSTL/HSTL), voltage, phase offset (±45 ns), and spread-spectrum control.

It supports flexible reference inputs - 8–30 MHz crystal, 5–200 MHz CMOS, 5–350 MHz SSTL/HSTL, or 5–710 MHz differential - and delivers glitchless frequency increment/decrement in 1 ppm steps via pin or I²C control. Loss-of-lock and loss-of-signal alarms provide real-time status monitoring.

Key Specifications

Pinout & Package

SI5338A-B05495-GMR is housed in a 24-lead QFN package (4 × 4 mm, 0.5 mm pitch) with exposed thermal pad. Pin assignments are standardized across the Si5338 family per Skyworks Rev. 1.6 datasheet.

Key Features

Applications

Equivalent & Alternatives

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

Compared with Si5338A-B05501-GMR, SI5338A-B05495-GMR offers full field reprogrammability but requires initial configuration; compared with LMK04832ISQE/NOPB, it delivers lower power and smaller footprint at the expense of deterministic latency control and ultra-low additive jitter performance.

Availability

SI5338A-B05495-GMR is available at Aetrix Electronics and suitable for Ethernet switch/router timing, PCIe Gen 4 server clocking, and FPGA-based broadcast video equipment requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for SI5338A-B05495-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 for wireless, broadband, automotive, and industrial markets.

The Si5338 product line was designed as a highly configurable, low-jitter clock generator family targeting space-constrained, multi-clock-domain systems such as networking switches, PCIe platforms, and broadcast video infrastructure.

FAQ

What is the primary function of the SI5338A-B05495-GMR?

The SI5338A-B05495-GMR is an I²C-programmable quad clock generator that synthesizes up to four independent, zero-ppm-accurate output frequencies from a single reference input. It serves as a drop-in replacement for multiple crystal oscillators in applications requiring low phase jitter (0.7 ps RMS), PCIe Gen 1–4 compliance, and flexible output formatting - all within a compact 4 × 4 mm QFN package.

Does the SI5338A-B05495-GMR support PCIe Gen 4 timing requirements?

Yes, the SI5338A-B05495-GMR meets PCIe Gen 4 common clock specifications with ≤0.45 ps RMS jitter (10 kHz–50 MHz) and supports both common clock and SRNS architectures. Its jitter performance is validated using the Skyworks PCIe Clock Jitter Tool and Intel Clock Jitter Tool v1.6.4, and it operates with PLL bandwidths of 2–4 MHz or 2–5 MHz to satisfy Gen 4 CDR requirements.

Can the SI5338A-B05495-GMR generate different output voltages on each channel?

Yes, the SI5338A-B05495-GMR provides independent output buffer supplies (VDDO0–VDDO3), allowing each of its four output banks to be powered at 1.5 V, 1.8 V, 2.5 V, or 3.3 V. This enables direct interfacing with mixed-voltage components - for example, driving 1.8 V LVDS SerDes, 2.5 V SSTL memory interfaces, and 3.3 V CMOS logic from a single device.

How is the SI5338A-B05495-GMR configured during system operation?

The SI5338A-B05495-GMR is configured via its I²C/SMBus-compatible serial interface (SCL/SDA pins), supporting standard-mode (100 kHz) and fast-mode (400 kHz) operation. Configuration is typically performed using Skyworks' ClockBuilder Pro software, which generates register maps and initialization scripts. Hardware pin control also enables basic functions like frequency increment/decrement and output enable/disable without host intervention.

What reference inputs does the SI5338A-B05495-GMR accept?

The SI5338A-B05495-GMR accepts multiple reference types: an 8–30 MHz fundamental-mode crystal connected to IN1/IN2; a 5–200 MHz CMOS-level signal on IN3 or IN4; a 5–350 MHz SSTL or HSTL signal; or a 5–710 MHz differential clock on IN1/IN2 or IN5/IN6. All inputs support automatic loss-of-signal detection with configurable release timing (2.6–5 µs detect, 0.01–1 µs release).