Skyworks Solutions Inc. SI5351A-B04697-GM

Overview

SI5351A-B04697-GM from Skyworks Solutions is an I²C-programmable 8-output CMOS clock generator with integrated crystal oscillator, generating free-running frequencies from 2.5 kHz to 200 MHz per output with 0 ppm synthesis error. It operates from a 25 or 27 MHz fundamental-mode AT-cut crystal and supports independent 1.8/2.5/3.3 V output supply rails (VDDOA–VDDOD) for level translation in mixed-voltage systems. Used in networking equipment for multi-domain clock synthesis.

For engineers reviewing the SI5351A-B04697-GM datasheet, SI5351A-B04697-GM pinout, SI5351A-B04697-GM application, or SI5351A-B04697-GM equivalent, this device delivers deterministic jitter performance (<70 ps pk-pk period jitter), programmable rise/fall times, glitchless frequency changes, and static phase offset control - critical for PCIe Gen 1-compliant timing and HCSL-compatible swing generation.

Technical Context

The SI5351A-B04697-GM implements a dual-PLL architecture with PLL A driven by the internal crystal oscillator (25/27 MHz), enabling fully free-running operation without external reference. Its eight high-resolution MultiSynth fractional dividers operate independently per output, supporting non-integer-related frequencies up to 200 MHz with exact synthesis.

It lacks VCXO or CLKIN input capability - distinguishing it from Si5351B/C variants - and relies solely on the internal XTAL oscillator as its sole frequency reference. All outputs are derived from PLL A; PLL B is unused in the Si5351A configuration.

Key Specifications

Pinout & Package

SI5351A-B04697-GM is housed in a 20-pin QFN package (4 mm × 4 mm, 0.5 mm pitch) with exposed thermal pad. Pin functions align with the Si5351A 20-QFN variant per Skyworks datasheet Rev. 1.3, Section 10.1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with Si5351A-B-GM, SI5351A-B04697-GM saves boot-time configuration effort; compared with Si5351C-B-GM, it removes unused synchronization circuitry, reducing power (–3 mA typical) and simplifying layout by eliminating CLKIN/VC routing.

Availability

SI5351A-B04697-GM is available at Aetrix Electronics and suitable for networking switch timing, residential gateway clocking, audio/video equipment, and laser range finder applications requiring stable component supply and guaranteed factory-programmed configuration.

Supply support for SI5351A-B04697-GM 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.

The Si5351 family is designed for cost-sensitive, multi-clock-domain systems needing flexible, software-configurable timing - specifically targeting replacement of crystals, oscillators, and discrete PLLs in consumer, enterprise, and industrial equipment.

FAQ

What is the reference source for SI5351A-B04697-GM?

The SI5351A-B04697-GM uses only an internal 25 or 27 MHz AT-cut crystal oscillator as its frequency reference. It does not support external CLKIN or VCXO control voltage inputs - those capabilities are exclusive to Si5351B and Si5351C variants. The crystal connects directly to XA/XB pins, with internal load capacitance configurable via register 183.

Does SI5351A-B04697-GM require external configuration after power-up?

No. SI5351A-B04697-GM contains factory-programmed configuration data in its on-chip EEPROM. Upon power-up, it automatically loads this configuration and begins generating its pre-defined output frequencies without host I²C intervention. This differs from blank-part variants like SI5351A-B-GM, which require runtime register writes.

What is the maximum number of unique high-frequency outputs supported by SI5351A-B04697-GM?

The SI5351A-B04697-GM supports no more than two unique output frequencies above 112.5 MHz simultaneously - for example, 125 MHz on CLK0 and 130 MHz on CLK1 is valid, but adding 150 MHz on CLK2 violates the architecture limit. Multiple outputs may replicate the same high-frequency signal (e.g., 125 MHz on CLK0–CLK3).

How does SI5351A-B04697-GM manage power supply sequencing?

SI5351A-B04697-GM requires that all output supply rails (VDDOA–VDDOD) be powered up either before or simultaneously with the core VDD supply. Violating this sequence - such as powering VDD before any VDDO - may cause undefined output behavior or increased jitter. The device draws 27–45 mA total with all 8 outputs active, depending on VDD voltage (2.5 V or 3.3 V).

Can SI5351A-B04697-GM generate HCSL-compatible output swings?

Yes. SI5351A-B04697-GM supports HCSL-compatible swing through programmable output drive strength and termination control. When configured with 50 Ω output impedance and appropriate VDDO (e.g., 1.8 V), it meets HCSL voltage thresholds (V_OH ≥ 0.75 V, V_OL ≤ 0.25 V) and edge rate requirements for PCIe Gen 1 and other serial link applications.