Skyworks Solutions Inc. SI5338A-B11789-GM

Overview

SI5338A-B11789-GM from Skyworks Solutions is a quad-output, I²C-programmable clock generator with MultiSynth™ frequency synthesis, delivering four independent low-jitter clocks (0.7 ps RMS typ) across LVPECL/LVDS/HCSL/CMOS/SSTL formats, supporting PCIe Gen 1–4 and Ethernet timing in telecom line cards and FPGA-based systems.

For engineers reviewing the SI5338A-B11789-GM datasheet, SI5338A-B11789-GM pinout, SI5338A-B11789-GM application, or SI5338A-B11789-GM equivalent, key selection criteria include its 4× differential output capability, 0 ppm synthesis accuracy, PCIe Gen 3 SRNS compliance, and flexible 1.5–3.3 V per-output voltage configuration.

Technical Context

The SI5338A-B11789-GM implements a two-stage PLL architecture: a high-stability reference stage followed by four independent MultiSynth™ fractional-N synthesizers, each with programmable R, M, and P dividers enabling any-frequency generation from 0.16 MHz to 710 MHz. It supports external crystal (8–30 MHz), CMOS (5–200 MHz), SSTL/HSTL (5–350 MHz), and differential (5–710 MHz) inputs.

Each output driver is independently configurable for format, voltage (1.5/1.8/2.5/3.3 V), phase offset (±45 ns, <20 ps step), and spread spectrum (0.5–5.0% at 33–63 kHz). Loss-of-lock and loss-of-signal alarms, plus I²C/SMBus interface, enable real-time monitoring and dynamic reconfiguration.

Key Specifications

Pinout & Package

SI5338A-B11789-GM uses a 24-lead QFN package (4 mm × 4 mm, 0.5 mm pitch) with exposed thermal pad. Pin functions are validated per Skyworks Rev. 1.6 datasheet, Figure 1 (Pin Assignments) and Section 7 (Pin Descriptions).

Key Features

Applications

Equivalent & Alternatives

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

Compared with Si5332A-D08889-GM and ICS8430I-01T, the SI5338A-B11789-GM uniquely balances programmability, PCIe Gen 4 readiness, and compact 24-QFN packaging-making it optimal for mid-channel-count, field-upgradable timing systems where design reuse and software-defined clocking are critical.

Availability

SI5338A-B11789-GM is available at Aetrix Electronics and suitable for PCIe switch timing, 10GbE PHY clocking, broadcast video sync generation, and FPGA-based test equipment requiring stable component supply across extended product lifecycles.

Supply support for SI5338A-B11789-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 for wireless, broadband, automotive, and industrial markets.

The Si5338 family was designed as a programmable, low-jitter clock generator platform for high-speed digital systems requiring flexible, software-configurable timing-targeting PCIe, Ethernet, and broadcast infrastructure applications.

FAQ

What is the primary function of the SI5338A-B11789-GM?

The SI5338A-B11789-GM is an I²C-programmable quad-output clock generator that synthesizes four independent, low-jitter frequencies (0.16–710 MHz) from a single reference input. Its MultiSynth™ technology enables true zero-ppm accuracy and supports PCIe Gen 1–4, Ethernet, and broadcast timing standards. The SI5338A-B11789-GM replaces multiple discrete oscillators while offering per-output format, voltage, and phase control.

Does the SI5338A-B11789-GM support PCIe Gen 4 Common Clock mode?

Yes, the SI5338A-B11789-GM delivers 0.15–0.45 ps RMS jitter in PCIe Gen 4 Common Clock mode (100 MHz HCSL output, PLL BW 2–5 MHz, CDR = 10 MHz), satisfying the PCI-SIG Base Specification 4.0 rev. 0.5 requirements. This performance is validated per Table 12 in the Skyworks Rev. 1.6 datasheet and confirmed using the Skyworks PCIe Clock Jitter Tool.

Can the SI5338A-B11789-GM generate both differential and single-ended outputs simultaneously?

Yes, the SI5338A-B11789-GM supports up to four differential outputs (CLK0A/B through CLK3A/B) and eight single-ended outputs (via internal termination of differential pairs), or any combination thereof. Each output bank (VDDO0–VDDO3) can be configured independently for LVPECL, LVDS, HCSL, CMOS, SSTL, or HSTL, allowing mixed signaling on a single device without external level shifters.

What is the minimum and maximum input reference frequency supported by the SI5338A-B11789-GM?

The SI5338A-B11789-GM accepts input references from 5 MHz to 710 MHz depending on interface type: 8–30 MHz for external crystal; 5–200 MHz for CMOS; 5–350 MHz for SSTL/HSTL; and 5–710 MHz for differential inputs. These ranges are specified in Table 6 of the Skyworks Rev. 1.6 datasheet and validated across –40 °C to +85 °C operating temperature.

How is the SI5338A-B11789-GM programmed and configured?

The SI5338A-B11789-GM is programmed via its I²C/SMBus-compatible serial interface (SCL/SDA pins) using Skyworks' ClockBuilder Pro software, which generates custom configuration files and registers settings. Configuration can also be performed dynamically in-system using pin-controlled frequency/phase increments (PINC/FDEC) or through firmware-driven I²C writes, enabling runtime clock adjustments without reset.