Skyworks Solutions Inc. SI5351A-B05913-GM

Overview

SI5351A-B05913-GM from Skyworks Solutions is an I²C-programmable 8-output CMOS clock generator with integrated VCXO, designed to replace crystals, crystal oscillators, and discrete PLLs in cost-sensitive embedded systems. It delivers up to eight independent frequencies from 2.5 kHz to 200 MHz with 0 ppm synthesis error, supports 1.8/2.5/3.3 V output voltage per bank, and operates from a 25 or 27 MHz fixed-frequency crystal.

For engineers reviewing the SI5351A-B05913-GM datasheet, SI5351A-B05913-GM pinout, SI5351A-B05913-GM application, or SI5351A-B05913-GM equivalent, key selection criteria include its 20-QFN (4×4 mm) package with 20 pins, VCXO tuning range of ±240 ppm at 3.3 V, <70 ps pk-pk period jitter (all outputs active), and support for I²C configuration with spread spectrum and static phase offset.

Technical Context

The SI5351A-B05913-GM implements a dual-PLL architecture with one PLL dedicated to VCXO operation and the other supporting free-running synthesis. Its MultiSynth fractional dividers provide independent frequency generation per output, enabling non-integer-related clocks across all eight channels.

It features separate VDDO supply pins (VDDOA–VDDOD) for level translation, configurable rise/fall times, glitchless frequency transitions, and programmable output delay. The device accepts only a crystal reference (no CLKIN), confirming it as the Si5351A variant-not B or C-per ordering guide Table 1.

Key Specifications

Pinout & Package

The SI5351A-B05913-GM is housed in a 20-pin QFN package (4 mm × 4 mm, 0.5 mm pitch) with exposed thermal pad. Pin functions are defined per Skyworks datasheet Section 10.1 (Si5351A 20-pin QFN).

Key Features

Applications

Equivalent & Alternatives

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

Compared with Si5351B-B-GM and Si5351C-B-GM, the SI5351A-B05913-GM provides lowest-cost, crystal-referenced multi-clock generation without VCXO or CLKIN complexity-ideal for standalone, free-running timing in consumer and industrial edge devices.

Availability

SI5351A-B05913-GM is available at Aetrix Electronics and suitable for audio/video equipment, networking gear, and handheld instrumentation requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for SI5351A-B05913-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 targets cost-sensitive, space-constrained applications needing flexible, software-configurable clock trees-designed specifically to consolidate discrete timing components into a single programmable IC.

FAQ

What is the reference clock requirement for SI5351A-B05913-GM?

The SI5351A-B05913-GM requires a 25 MHz or 27 MHz fundamental-mode AT-cut crystal connected to XA/XB pins. It does not accept external CLKIN; this distinguishes it from Si5351B/C variants. Internal load capacitance (0/6/8/10 pF) is programmable via register 183, and crystal ESR must be ≤150 Ω per datasheet Table 8. SI5351A-B05913-GM cannot operate with arbitrary clock inputs.

Does SI5351A-B05913-GM support VCXO functionality?

Yes, SI5351A-B05913-GM includes an integrated VCXO, confirmed by its part number suffix "-B" (denoting Si5351B variant per Skyworks ordering guide). It supports voltage-controlled frequency pulling with ±240 ppm range at 3.3 V supply, linear gain (18–150 ppm/V), and 10 kHz modulation bandwidth. This VCXO operates using the same 25/27 MHz crystal reference, eliminating need for external pullable crystals.

What is the maximum number of unique high-frequency outputs supported by SI5351A-B05913-GM?

SI5351A-B05913-GM supports up to two unique output frequencies above 112.5 MHz simultaneously (e.g., 125 MHz on CLK0 and 130 MHz on CLK1). Additional outputs above 112.5 MHz must duplicate one of those two frequencies. This limitation arises from internal PLL resource constraints and is specified in Table 7 footnote 1. All eight outputs remain fully configurable below 112.5 MHz.

How is power supply sequencing handled on SI5351A-B05913-GM?

Per datasheet Table 3, all VDDOx supply pins must be powered up either before or simultaneously with VDD core-never after. Violating this sequence risks undefined behavior or latch-up. SI5351A-B05913-GM draws 27 mA typical with all 8 outputs enabled (VDD = 3.3 V), and each output buffer consumes 2.2–5.6 mA depending on load and frequency. Decoupling requires 100 nF ceramic capacitors near each VDD/VDDO pin.

Can SI5351A-B05913-GM generate sub-1 MHz clock frequencies?

Yes, SI5351A-B05913-GM supports frequencies as low as 2.5 kHz on any output, achieved via integer division in the output stage after MultiSynth synthesis. This capability enables use cases such as UART baud rate generation (e.g., 3.6864 MHz, 1.8432 MHz), watchdog timers, or slow-control logic clocks. The minimum frequency applies independently per output and does not affect other channels.