Skyworks Solutions Inc. SI5355A-B04673-GMR

Overview

SI5355A-B04673-GMR from Skyworks Solutions is a quad-frequency, 8-output CMOS clock generator synthesizing four independent non-integer-related frequencies from 1 to 200 MHz per bank. It features guaranteed 0 ppm frequency synthesis error via MultiSynth fractional divider technology, 50 ps pk-pk period jitter, and supports 1.8/2.5/3.3 V core and per-bank output supply voltages. It serves as a single-device replacement for multiple crystal oscillators and clock ICs in Ethernet switch timing.

For engineers reviewing the SI5355A-B04673-GMR datasheet, SI5355A-B04673-GMR pinout, SI5355A-B04673-GMR application, or SI5355A-B04673-GMR equivalent, key selection criteria include its factory-configured pin-controlled triple-profile capability, loss-of-signal (LOS) alarm output, per-bank OEB control, and 4×4 mm 24-QFN package with separate VDDO rails for mixed-voltage system clock distribution.

Technical Context

The SI5355A-B04673-GMR implements a single high-frequency VCO feeding four independent MultiSynth fractional-N dividers-each delivering precise 1–200 MHz outputs with dynamic phase error correction. Its architecture eliminates integer-ratio constraints and guarantees 0 ppm synthesis error across all configured frequencies.

It accepts either a 25/27 MHz fundamental crystal (XA/XB) or a 5–200 MHz single-ended CMOS reference (CLKIN), with five programmable pins (P1–P5) assignable to OEB_ALL/OEB_A–D, FS0/FS1, or RESET functions. The open-drain LOS pin reports both loss-of-input-signal and loss-of-lock conditions.

Key Specifications

Pinout & Package

SI5355A-B04673-GMR is housed in a 4×4 mm 24-QFN package with exposed thermal pad tied to GND. Pin assignments are fixed per Skyworks Rev. 1.2 datasheet.

Key Features

Applications

Equivalent & Alternatives

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

Compared with Si5356A-B04674-GM, SI5355A-B04673-GMR trades 0.8 ps rms phase jitter and +105 °C rating for lower unit cost and sufficient performance in commercial-temperature networking and printing systems; versus ICS853S01AGI-01LFT, it provides full frequency agility and multi-profile capability at the expense of fixed-output simplicity.

Availability

SI5355A-B04673-GMR is available at Aetrix Electronics and suitable for Ethernet switches, laser printers, audio/video receivers, and server management subsystems requiring stable component supply, factory-programmed timing solutions, and long-term production continuity.

Supply support for SI5355A-B04673-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 products.

The SI5355A-B04673-GMR belongs to Skyworks' Any-Frequency Clock Generator product line, designed to replace multiple crystals and clock ICs in bandwidth-constrained, multi-protocol systems requiring flexible, low-jitter timing with minimal board space.

FAQ

What input reference options does the SI5355A-B04673-GMR support?

The SI5355A-B04673-GMR supports two input reference modes: a 25 or 27 MHz fundamental-mode crystal connected across XA and XB pins, or a 5–200 MHz single-ended CMOS clock applied to the CLKIN pin. Crystal mode uses on-chip 12–13 pF load capacitance; CMOS mode requires DC-coupled input with optional series termination. Both options are mutually exclusive and selected during ClockBuilder configuration.

How many independent frequency configurations can the SI5355A-B04673-GMR store?

The SI5355A-B04673-GMR supports up to three independent, factory-programmed frequency configurations stored in on-chip memory. These are selected dynamically using the FS0 and FS1 pins - for example, FS0=0/FS1=1 selects Profile 1, while FS0=1/FS1=0 selects Profile 2. A RESET pulse is required to switch between profiles, ensuring glitch-free transitions and deterministic timing behavior in the SI5355A-B04673-GMR.

Does the SI5355A-B04673-GMR require external configuration after power-up?

No, the SI5355A-B04673-GMR is a pin-controlled, factory-customized device with all configuration parameters (frequencies, pin functions, VDDO assignments) permanently programmed during manufacturing via ClockBuilder. It operates autonomously at power-up with no I²C bus, firmware, or external EEPROM required - making it ideal for secure, tamper-resistant, or boot-critical timing applications involving the SI5355A-B04673-GMR.

What is the function of the LOS pin on the SI5355A-B04673-GMR?

The LOS (Loss of Signal) pin on the SI5355A-B04673-GMR is an open-drain output that asserts low during either loss of input clock (LOS) or loss of PLL lock (LOL). It requires an external pullup resistor (1–4 kΩ) and interfaces directly to system supervisors or BMCs for real-time clock health monitoring. When asserted, the SI5355A-B04673-GMR continues outputting clocks but may drift up to ±5% in LOS condition or disable outputs entirely in LOL condition.

Can the SI5355A-B04673-GMR drive different output voltage levels simultaneously?

Yes, the SI5355A-B04673-GMR supports simultaneous mixed-voltage operation: VDDOA, VDDOB, VDDOC, and VDDOD are independent supply pins allowing each of the four output banks (CLK0/1, CLK2/3, CLK4/5, CLK6/7) to operate at 1.8 V, 2.5 V, or 3.3 V independently. This eliminates level-shifters in heterogeneous SoC designs and enables direct interfacing with processors, PHYs, and memory interfaces operating at differing I/O voltages - a core capability of the SI5355A-B04673-GMR.