Skyworks Solutions Inc. SI5351B-B13189-GM1

Overview

SI5351B-B13189-GM1 from Skyworks Solutions is an I²C-programmable, 4-output CMOS clock generator with integrated VCXO, generating frequencies from 2.5 kHz to 200 MHz per output with 0 ppm synthesis error. It replaces crystals, crystal oscillators, and discrete VCXOs in cost-sensitive timing applications, supporting independent voltage supplies (VDD = 2.5/3.3 V; VDDO = 1.8/2.5/3.3 V) and operating across –40°C to +85°C.

For engineers reviewing the SI5351B-B13189-GM1 datasheet, SI5351B-B13189-GM1 pinout, SI5351B-B13189-GM1 application, or SI5351B-B13189-GM1 equivalent, this device delivers precise multi-frequency synthesis with VCXO tuning capability, low period jitter (<70 ps pk-pk), configurable spread spectrum, and HCSL-compatible output swing - critical for audio/video equipment, networking gear, and embedded instrumentation timing subsystems.

Technical Context

The SI5351B-B13189-GM1 implements a dual-PLL architecture: PLL A (SSC-capable) and PLL B (VCXO-based), both fed by either a 25/27 MHz crystal or optional CLKIN (10–100 MHz). Its eight MultiSynth fractional dividers enable independent frequency synthesis per output, with static phase offset control and glitchless frequency transitions.

It supports VCXO tuning over 0–VDD range with configurable gain (18–150 ppm/V) and ±240 ppm pull range at 3.3 V, while maintaining high linearity (±5%) and 10 kHz modulation bandwidth. Output drive strength, rise/fall time, and spread spectrum (down/center, 0.1–2.5% deviation at 31.5 kHz) are programmable per channel.

Key Specifications

Pinout & Package

SI5351B-B13189-GM1 is housed in a 16-pin QFN package (3 mm × 3 mm, 0.5 mm pitch) with exposed thermal pad. Pin functions are validated per Skyworks Si5351B 16-QFN pinout specification (Rev. 1.3, Section 10.5).

Key Features

Applications

Equivalent & Alternatives

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

Compared with Si5351A-B-GM1 and Si5351C-B-GM1, the SI5351B-B13189-GM1 uniquely provides analog VCXO control for closed-loop frequency adjustment - essential for applications requiring real-time drift correction, temperature compensation, or phase-locking to analog control voltages without external PLL circuitry.

Availability

SI5351B-B13189-GM1 is available at Aetrix Electronics and suitable for audio/video equipment, networking gear, and embedded instrumentation requiring stable component supply, long-term lifecycle support, and consistent electrical performance across temperature and voltage variations.

Supply support for SI5351B-B13189-GM1 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 SI5351B-B13189-GM1 belongs to Skyworks' Si5351 family of I²C-programmable clock generators designed for cost-sensitive, space-constrained applications needing flexible, multi-frequency timing with VCXO capability - targeting consumer, industrial, and communications end markets.

FAQ

What is the maximum output frequency supported by the SI5351B-B13189-GM1?

The SI5351B-B13189-GM1 supports output frequencies from 2.5 kHz up to 200 MHz on each of its four outputs. However, only two unique frequencies above 112.5 MHz may be generated simultaneously - for example, 125 MHz and 150 MHz can coexist, but adding a third >112.5 MHz frequency (e.g., 130 MHz) violates the device's synthesis constraint. This limitation arises from internal PLL resource allocation in the Si5351B architecture.

Does the SI5351B-B13189-GM1 require an external crystal?

Yes, the SI5351B-B13189-GM1 requires a 25 MHz or 27 MHz fundamental-mode AT-cut crystal connected across XA and XB pins. The device includes programmable internal load capacitance (0/6/8/10 pF) to eliminate external capacitors for standard 8–10 pF crystals. Crystals with 12 pF load requirement may need ≤2 pF additional external capacitance. No external crystal is needed if using CLKIN - but CLKIN is not functional in the Si5351B variant.

Can the SI5351B-B13189-GM1 generate spread spectrum clocking on individual outputs?

Yes, the SI5351B-B13189-GM1 supports per-output spread spectrum clocking (SSC) with selectable down-spread (–0.1% to –2.5%) or center-spread (±0.1% to ±1.5%) modulation at a fixed 31.5 kHz rate. SSC is configured independently for each of the four outputs via I²C register writes, allowing targeted EMI reduction on noise-sensitive interfaces (e.g., USB, HDMI) while leaving other clocks unmodulated for jitter-critical paths.

What is the function of the VC pin on the SI5351B-B13189-GM1?

The VC pin on the SI5351B-B13189-GM1 is the analog voltage control input for its integrated VCXO. Applying a DC voltage from 0 V to VDD tunes the output frequency linearly within a configurable range (up to ±240 ppm at 3.3 V). This enables closed-loop frequency stabilization, temperature compensation, or synchronization to analog control signals - eliminating the need for external VCXO components and reducing system-level calibration complexity.

Is the SI5351B-B13189-GM1 pin-compatible with other Si5351 variants in the same package?

Yes, the SI5351B-B13189-GM1 in the 16-pin QFN package shares identical pinout and footprint with Si5351A-B-GM1 and Si5351C-B-GM1. All three variants use the same mechanical layout, thermal pad, and I/O assignment. However, functional differences exist: CLKIN (Pin 15) is unused in Si5351B, and VC (Pin 10) is inactive in Si5351A/C. PCB designs can accommodate all three variants with software configuration only - no layout change required.