Skyworks Solutions Inc. SI5332BC08480-GM3

Overview

SI5332BC08480-GM3 from Silicon Labs is a 12-output, any-frequency programmable clock generator with MultiSynth™ fractional synthesis, delivering 190 fs RMS phase jitter (external crystal), 5–333.33 MHz differential output range, and user-configurable LVDS/LVPECL/HCSL/LVCMOS signal formats per output. It serves as a high-density clock tree solution in multi-protocol Ethernet switches.

For engineers reviewing the SI5332BC08480-GM3 datasheet, SI5332BC08480-GM3 pinout, SI5332BC08480-GM3 application, or SI5332BC08480-GM3 equivalent, key selection considerations include its 48-pin QFN package, embedded 50 MHz crystal option (Si5332C variant), 3 independent fractional synthesis paths, and support for mixed-supply banks with independent VDDO pins.

Technical Context

The SI5332BC08480-GM3 implements a two-stage synthesis architecture: a wideband PLL locks to an external 16–50 MHz crystal (XA/XB) or differential input clock (10–250 MHz), then feeds up to three independent MultiSynth fractional dividers and five integer dividers. Its cross-point mux routes any synthesized frequency to any of twelve differential outputs.

Each output bank (A–D) shares a dedicated VDDO supply (1.8/2.5/3.3 V), enabling mixed-voltage clock distribution. The device supports glitchless on-the-fly frequency changes across up to 16 stored profiles, with configurable skew (35 ps steps, ±122.5 ps range) and synchronous output enable/disable via hardware pins or I²C.

Key Specifications

Pinout & Package

SI5332BC08480-GM3 uses a 6×6 mm, 48-pin QFN package (RoHS-6 compliant) with exposed thermal pad. Pin functions are defined per the Si5332 48-QFN pinout (Rev. 1.1, Section 6.1), supporting 12 differential outputs, 7 universal hardware input pins, and dual reference inputs (XA/XB).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SI5332BC08480-GM3, the Si5332AC08480-GM3 extends maximum output frequency to 333.33 MHz while retaining identical jitter and package compatibility, whereas the Si5332DC08480-GM3 sacrifices fractional synthesis flexibility for reduced NVM footprint and simpler register programming.

Availability

SI5332BC08480-GM3 is available at Aetrix Electronics and suitable for Ethernet switches, PCIe server platforms, and broadcast video equipment requiring stable component supply, long-term lifecycle support, and factory-programmed configuration traceability.

Supply support for SI5332BC08480-GM3 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

Silicon Labs is a fabless semiconductor company specializing in timing, wireless, and IoT solutions, with over 20 years of leadership in precision clock technology.

The Si5332 family was designed to replace multiple fixed-frequency oscillators and fanout buffers with a single programmable clock generator for high-speed networking, data center, and multimedia applications.

FAQ

What is the reference clock requirement for SI5332BC08480-GM3?

The SI5332BC08480-GM3 requires an external 16–50 MHz fundamental-mode crystal connected to XA/XB pins. It does not include an embedded crystal (unlike Si5332E–H variants). The crystal must meet load capacitance specifications (2–30 pF, configurable via register), and PCB layout must follow Silicon Labs' low-jitter crystal routing guidelines to maintain 190 fs RMS performance.

Does SI5332BC08480-GM3 support PCIe Gen4 compliance?

Yes, SI5332BC08480-GM3 meets PCIe Gen4 requirements with 190 fs RMS phase jitter (measured using external crystal) and supports SRIS (Spread Spectrum Independent Subsystem) via programmable down-spread modulation (–0.1% to –2.5%). Its output frequency range (5–333.33 MHz) covers all PCIe Gen4 reference clocks including 100 MHz and 100 MHz ±300 ppm.

How many independent voltage domains does SI5332BC08480-GM3 support for clock outputs?

SI5332BC08480-GM3 supports six independent output supply domains via VDDO0–VDDO5 pins. These power four differential output banks (A–D), enabling mixed-voltage operation - for example, Bank A at 1.8 V for SerDes, Bank C at 2.5 V for PHY, and Bank D at 3.3 V for legacy peripherals - all from a single SI5332BC08480-GM3 device.

Can SI5332BC08480-GM3 generate non-integer related output frequencies?

Yes, SI5332BC08480-GM3 uses MultiSynth™ fractional synthesis to generate any output frequency between 5–250 MHz with zero ppm error - for example, simultaneously producing 156.25 MHz (Ethernet), 266.67 MHz (DDR4), and 400.012 MHz (custom ADC sampling) from a single 25 MHz crystal reference, without external PLLs or dividers.

What configuration tools are supported for SI5332BC08480-GM3?

SI5332BC08480-GM3 is configured using Silicon Labs' ClockBuilder Pro software, which generates a custom part number (e.g., SI5332BC08480) and factory-programmed NVM image. Runtime reconfiguration is supported via standard I²C interface (SCLK/SDATA pins), and hardware input pins (IN1–IN7) can be assigned to functions like output enable or spread spectrum control without firmware intervention.