Skyworks Solutions Inc. SI5351A-B04760-GM

Overview

SI5351A-B04760-GM from Skyworks Solutions is an I²C-programmable, 8-output CMOS clock generator with integrated crystal oscillator and VCXO functionality. It synthesizes up to eight independent, non-integer-related frequencies from 2.5 kHz to 200 MHz with 0 ppm frequency error, operates from a 25 or 27 MHz crystal, and supports configurable output voltages (1.8/2.5/3.3 V) for mixed-signal system clocking in networking and embedded instrumentation.

For engineers reviewing the SI5351A-B04760-GM datasheet, SI5351A-B04760-GM pinout, SI5351A-B04760-GM application, or SI5351A-B04760-GM equivalent, this device delivers precise multi-domain clock synthesis without external PLLs or discrete VCXOs-enabling compact, cost-sensitive timing solutions in residential gateways, laser range finders, and audio/video equipment where jitter-critical, programmable clock distribution is required.

Technical Context

The SI5351A-B04760-GM implements a dual-PLL architecture: PLL A accepts only the internal crystal (25/27 MHz), while PLL B is bypassed in Si5351A variants-eliminating VCXO control voltage (VC) dependency. Frequency synthesis uses high-resolution MultiSynth fractional dividers per output, enabling independent, glitchless frequency changes and static phase offset configuration.

It features separate VDD (2.5/3.3 V core) and VDDOx (1.8/2.5/3.3 V per output bank) supplies, supports spread spectrum on each output (±0.1–±1.5% deviation at 31.5 kHz), and provides < 70 ps pk-pk period jitter across all eight outputs under typical conditions with 5 pF load.

Key Specifications

Pinout & Package

SI5351A-B04760-GM is housed in a 20-pin QFN package (4 mm × 4 mm, 0.5 mm pitch) with exposed thermal pad. Pin functions are validated per Skyworks Si5351A 20-pin QFN specification (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 Si5351B-B-GM and Si5341-A06489-GM, SI5351A-B04760-GM delivers best-in-class value for fixed-reference, multi-output clock generation-offering 8 outputs, 0 ppm synthesis, and < 70 ps jitter at lower cost and smaller footprint than higher-tier alternatives, without unnecessary VCXO complexity or over-spec'd jitter performance.

Availability

SI5351A-B04760-GM is available at Aetrix Electronics and suitable for residential gateways, laser range finders, and audio/video equipment requiring stable component supply, long-term production continuity, and I²C-field-programmable timing flexibility.

Supply support for SI5351A-B04760-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 leader in analog and mixed-signal semiconductors, specializing in RF, timing, and precision analog components for communications, automotive, and industrial markets.

The Si5351 family was designed specifically for cost-sensitive, space-constrained applications requiring flexible, software-configurable clock generation-replacing crystals, oscillators, and discrete PLLs in consumer, networking, and instrumentation systems.

FAQ

What is the maximum number of unique frequencies above 112.5 MHz that SI5351A-B04760-GM can generate simultaneously?

The SI5351A-B04760-GM supports exactly two unique frequencies above 112.5 MHz at the same time-for example, 125 MHz on CLK0 and 130 MHz on CLK1. Additional outputs may replicate those frequencies (e.g., 125 MHz on CLK2–CLK3), but no third distinct frequency >112.5 MHz is permitted per Skyworks Rev. 1.3 specification. This constraint arises from internal PLL bandwidth and MultiSynth resource allocation in the SI5351A-B04760-GM.

Does SI5351A-B04760-GM require external load capacitors for its 25 MHz crystal?

No-SI5351A-B04760-GM integrates programmable internal load capacitance (0, 6, 8, or 10 pF) and is optimized for standard 6–12 pF-load 25 MHz or 27 MHz AT-cut crystals. External capacitors are only needed if the crystal requires >10 pF total load (e.g., 12 pF), in which case ≤2 pF additional capacitance may be added externally. The SI5351A-B04760-GM datasheet explicitly states internal load caps eliminate external components in most cases.

Can SI5351A-B04760-GM generate a 100 MHz clock with 50% duty cycle?

Yes-SI5351A-B04760-GM guarantees 45–55% duty cycle for output frequencies below 160 MHz when measured at VDD/2, including 100 MHz. This meets standard CMOS timing requirements for FPGA and microcontroller clock inputs. Duty cycle is maintained across temperature (–40°C to +85°C) and supply voltage (2.5 V or 3.3 V) per Table 7 in the official SI5351A-B04760-GM datasheet.

Is the VC pin used in SI5351A-B04760-GM, and how should it be handled?

No-the VC pin is not functional in SI5351A-B04760-GM, as it belongs to the Si5351B/C variants with VCXO capability. Per Skyworks documentation, the VC pin must be tied to GND or left unconnected (floating) in Si5351A designs. Leaving it floating is acceptable, but grounding prevents noise coupling and aligns with recommended layout practices for the SI5351A-B04760-GM.

What is the typical power consumption of SI5351A-B04760-GM when all eight outputs are enabled?

When all eight outputs are enabled, SI5351A-B04760-GM draws 27–45 mA from the core VDD supply (2.5 V or 3.3 V) and up to 5.6 mA per active output from its respective VDDOx rail (e.g., 8 × 5.6 mA = 44.8 mA total output current). Total system current depends on output count, drive strength, and VDDOx voltage-but core IDD remains within 27–45 mA as specified in Table 4 of the SI5351A-B04760-GM datasheet.