Skyworks Solutions Inc. SI5338J-B05415-GM

Overview

SI5338J-B05415-GM from Skyworks Solutions is an I²C-programmable quad clock generator with four independent differential output drivers, 0.7 ps RMS typical phase jitter, PCIe Gen 1–4 Common Clock and Gen 3 SRNS compliance, and support for LVPECL/LVDS/HCSL/CMOS/SSTL/HSTL output formats up to 710 MHz. It replaces multiple crystal oscillators in high-speed serial interface timing applications such as PCIe root complexes and FPGA-based compute platforms.

For engineers reviewing the SI5338J-B05415-GM datasheet, SI5338J-B05415-GM pinout, SI5338J-B05415-GM application, or SI5338J-B05415-GM equivalent, key selection criteria include its MultiSynth™ fractional-N synthesis architecture, per-output voltage configurability (1.5–3.3 V), independent phase/frequency increment/decrement control (<20 ps / 1 ppm steps), and 24-pin 4×4 mm QFN package with integrated loss-of-lock and loss-of-signal alarms.

Technical Context

The SI5338J-B05415-GM implements a two-stage PLL architecture: a high-stability integer-N Phase-Locked Loop (Stage 1) locks to one of six input references (crystal, CMOS, SSTL/HSTL, or differential), followed by four independent MultiSynth™ fractional-N synthesis blocks (Stage 2) generating outputs with 1 ppb frequency resolution. Each output driver supports format- and voltage-selectable termination with programmable slew rate and drive strength.

It operates across –40°C to +85°C with core supply options of 1.8 V, 2.5 V, or 3.3 V and output buffer supplies from 1.4 V to 3.63 V. The device features I²C/SMBus-compatible configuration, nonvolatile OTP memory for factory programming, and real-time status monitoring via INTR pin with configurable alarm thresholds for loss-of-signal and loss-of-lock conditions.

Key Specifications

Pinout & Package

SI5338J-B05415-GM uses a 24-pin, 4 mm × 4 mm QFN package with exposed thermal pad. Pin 1 is top-left corner (IN1), pin 24 is bottom-right (GND). Package conforms to JEDEC MO-220, variant VGGQF-N24.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad-output programmable clock generator applications.

Compared with SI5338J-B05415-GM, Si5332A-D05415-GM offers superior jitter and integrated power management but sacrifices one output and programmability flexibility, while ICS853S01AGI-01LFT provides deterministic fanout at lower cost but no frequency synthesis or runtime configuration capability.

Availability

SI5338J-B05415-GM is available at Aetrix Electronics and suitable for PCIe Gen 4 server platforms, FPGA-based telecom line cards, and broadcast video equipment requiring stable component supply, long-term lifecycle assurance, and full traceability.

Supply support for SI5338J-B05415-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 highly configurable, low-jitter clock generator platform targeting high-speed serial interface timing in datacenter, networking, and broadcast infrastructure where multi-protocol clock synthesis and PCIe compliance are mandatory.

FAQ

What is the maximum output frequency supported by SI5338J-B05415-GM in LVPECL mode?

The SI5338J-B05415-GM supports LVPECL outputs up to 710 MHz, as confirmed in Table 6 of the datasheet. This applies when operating in integer synthesis mode with appropriate VCO and MultiSynth divider settings. Frequencies above 350 MHz require use of Fvco/4 or Fvco/6 synthesis paths, limiting simultaneous high-frequency outputs to two unique values.

Does SI5338J-B05415-GM support PCIe Gen 4 Separate Reference No Spread (SRNS) timing?

Yes, SI5338J-B05415-GM is explicitly validated for PCIe Gen 3 SRNS and meets PCIe Gen 4 common clock jitter requirements. Its 0.11–0.32 ps RMS jitter in SRNS mode (per Table 12) satisfies the PCI-SIG specification when configured with PLL bandwidth of 2–4 MHz and CDR = 10 MHz.

Can SI5338J-B05415-GM generate different output voltages on each channel?

Yes, SI5338J-B05415-GM provides independent VDDO0–VDDO3 pins, allowing each of its four output drivers to be powered at 1.5 V, 1.8 V, 2.5 V, or 3.3 V. This enables direct interfacing with mixed-voltage ASICs, FPGAs, and PHYs without external level shifters.

How is the SI5338J-B05415-GM programmed, and is factory programming available?

SI5338J-B05415-GM is programmed via I²C/SMBus interface using Skyworks' ClockBuilder Pro software. It includes one-time-programmable (OTP) nonvolatile memory, enabling factory configuration of startup frequencies, formats, and voltages - eliminating the need for external EEPROM or host initialization code.

What thermal performance can be expected from SI5338J-B05415-GM in a standard 4-layer PCB layout?

With proper thermal pad soldering and 1 in² copper pour connected to the exposed pad, SI5338J-B05415-GM achieves θJA = 37°C/W (still air). At 45 mA core current and 3.3 V supply, junction temperature rise is ~55°C above ambient - well within the 150°C absolute max rating and suitable for industrial-temperature operation.