Skyworks Solutions Inc. SI52254A-D01AMR

Overview

SI52254A-D01AMR from Skyworks Solutions is a 4-output automotive-grade PCIe Gen1/2/3/4/5 clock generator delivering four 100 MHz HCSL differential clock outputs with internal 85 Ω or 100 Ω line matching, 0.025 ps RMS jitter (Gen5), and –40 to +105 °C operation. It serves as a common-clock or SRIS timing source in high-reliability ADAS and infotainment systems.

For engineers reviewing the SI52254A-D01AMR datasheet, SI52254A-D01AMR pinout, SI52254A-D01AMR application, or SI52254A-D01AMR equivalent, key selection criteria include PCIe Gen5 jitter compliance, hardware-controlled output enable and spread spectrum, integrated HCSL termination, and AEC-Q100 Grade 2 qualification for automotive ECU timing.

Technical Context

The SI52254A-D01AMR integrates a low-jitter PLL with triangular spread spectrum modulation (0.25% or 0.5% down-spread at 31.5 kHz) and supports both crystal (25 MHz) and external clock input. Its architecture enables simultaneous PCIe Gen5 common-clock and SRIS compliance with <0.04 ps RMS total jitter under specified conditions.

All four HCSL outputs feature individual OE# control pins, impedance-select (IMP_SEL) sampled at power-up, and dedicated VDDO supplies per output pair. The device includes an active-low open-drain Loss-of-Signal (LOS) indicator tied to crystal presence detection below ~10 MHz.

Key Specifications

Pinout & Package

SI52254A-D01AMR uses a 5×5 mm, 32-pin QFN package (RoHS-6 compliant, matte tin finish) with exposed thermal pad. Pin count and layout match Skyworks' documented Si52254A-D01AM 32-QFN footprint (document revision 1.0, page 23).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SI52254A-D01AMR, the SI52254A-D01AM offers identical performance in tray form but lacks tape-and-reel logistics for high-volume SMT, while the ICS8430I-01T provides lower-cost Gen3 timing at the expense of PCIe roadmap scalability, automotive qualification, and hardware configurability.

Availability

SI52254A-D01AMR is available at Aetrix Electronics and suitable for automotive ADAS domain controllers, infotainment head units, and radar sensor modules requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for SI52254A-D01AMR 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, automotive, and industrial markets.

The Si52254 family is designed specifically for automotive PCIe timing applications, delivering Gen1–Gen5 compliance, AEC-Q100 Grade 2 qualification, and hardware-configurable features to meet stringent automotive ECU requirements.

FAQ

What is the maximum operating temperature for SI52254A-D01AMR?

The SI52254A-D01AMR is rated for continuous operation from –40 °C to +105 °C ambient, meeting AEC-Q100 Grade 2 automotive qualification. Its thermal resistance (θJA = 28.4 °C/W in still air) ensures safe junction temperatures below 125 °C even at full 4-output load under worst-case conditions.

Does SI52254A-D01AMR support PCIe Gen5 SRIS mode?

Yes, SI52254A-D01AMR supports PCIe Gen5 SRIS with 0.08–0.10 ps RMS jitter (max), as verified in Table 5.6 of the official datasheet. It meets Gen5 SRIS specifications when configured with appropriate PLL bandwidth and spread spectrum disabled.

How is impedance selection implemented on SI52254A-D01AMR?

SI52254A-D01AMR uses the IMP_SEL pin to select internal termination: logic low configures 100 Ω matching, logic high selects 85 Ω. This setting is latched at power-up only and applies uniformly to all four HCSL output pairs.

Can SI52254A-D01AMR accept a 25 MHz clock input instead of a crystal?

Yes, SI52254A-D01AMR accepts a 25 MHz single-ended CMOS clock on the XA pin (with XB left floating or grounded), per Section 3.2 of the datasheet. Crystal operation remains the recommended method for lowest phase noise and jitter.

What is the function of the LOS pin on SI52254A-D01AMR?

The LOS pin on SI52254A-D01AMR is an active-low, open-drain output indicating loss of valid crystal input - it asserts low when reference frequency falls below ~10 MHz. An external 1–10 kΩ pull-up resistor is required for proper operation.