Skyworks Solutions Inc. SI34061FB12V4KIT

Overview

SI34061FB12V4KIT from Skyworks Solutions is a Class 4, 30 W, 12 V EMI-compliant isolated evaluation board (EVB) for Power over Ethernet (PoE+) Powered Device (PD) applications. It implements a flyback topology with IEEE 802.3bt compatibility, synchronous rectification, and integrated transient overvoltage protection, delivering 12 V/2.5 A output from PoE or wall adapter input.

For engineers reviewing the SI34061FB12V4KIT datasheet, SI34061FB12V4KIT pinout, SI34061FB12V4KIT application, or SI34061FB12V4KIT equivalent, this EVB provides verified reference design validation for PoE+ PD power supply development-including end-to-end efficiency measurement (89.8–92.5%), EN55032 Class B radiated/conducted EMI compliance, and dual-input priority switching between PSE and 33–57 V wall adapter.

Technical Context

The SI34061FB12V4KIT implements the Si34061 IC-a fully integrated IEEE 802.3bt-compliant PoE+ PD controller with peak-current-mode dc-dc control, adaptive soft-start, maintain-power-signature (MPS), and programmable switching frequency (200 kHz via R14). It supports both endspan and midspan PoE powering and includes ASUP pin-based wall-adapter priority detection.

This board uses external high-side switch (Q1: SQJ476EP-T1) and synchronous rectifier (U1: NVMFS5C680NLT1G), with configurable current limiting via R33 (0.3 Ω) and detection resistor selection (R21 = 24.9 kΩ for Schottky bridge). It passes IEC 61000-4-5 surge testing up to 4.4 kV common-mode and supports optional TVS (e.g., SMDJ58A) for enhanced immunity.

Key Specifications

Availability

SI34061FB12V4KIT is available at Aetrix Electronics and suitable for PoE-powered surveillance cameras, VoIP phones, wireless access points, and industrial IoT edge nodes requiring stable component supply, pre-validated EMI compliance, and dual-input power architecture.

Supply support for SI34061FB12V4KIT 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 SI34061FB12V4KIT belongs to Skyworks' PoE+ PD evaluation platform family, designed to accelerate time-to-market for IEEE 802.3bt-compliant powered devices by providing production-ready, EMI-certified reference designs with full test data and layout documentation.

FAQ

What is the primary function of the SI34061FB12V4KIT?

The SI34061FB12V4KIT is an evaluation board for the Si34061 PoE+ PD controller IC. It demonstrates a complete, isolated 12 V/2.5 A, 30 W flyback power supply compliant with IEEE 802.3bt Type 2/Class 4. The SI34061FB12V4KIT enables rapid validation of PoE+ PD designs including efficiency, EMI, thermal behavior, and dual-input (PSE + wall adapter) operation.

Does the SI34061FB12V4KIT support both endspan and midspan PoE configurations?

Yes, the SI34061FB12V4KIT supports both endspan and midspan PoE configurations. Its RJ45 interface (J1) accepts power and data simultaneously, and the board's schematic and layout are validated for Gigabit Ethernet (10/100/1000BASE-T) systems. Figure 1 and Figure 2 in the user guide explicitly show lab PSU connections for both topologies.

How does the SI34061FB12V4KIT handle power source priority between PSE and wall adapter?

The SI34061FB12V4KIT uses the ASUP pin to detect wall adapter presence via J3. When active, the ASUP signal triggers automatic switchover from PSE to wall adapter with zero output interruption. In wall adapter mode, the SI34061FB12V4KIT presents a non-valid detection signature to the PSE, preventing unintended port shutdown while maintaining continuous 12 V output.

What EMI standards does the SI34061FB12V4KIT meet, and how was compliance verified?

The SI34061FB12V4KIT meets EN55032 Class B for both conducted (average and peak detectors) and radiated emissions. Testing used 50 V input and 30 W full load, with radiated measurements performed in vertical/horizontal polarizations and quasi-peak verification at critical frequencies. Figures 26 and 28 in the user guide confirm pass/fail results against the Class B limit line.

Can the SI34061FB12V4KIT be used for Class 3 (15.4 W) applications?

Yes, the SI34061FB12V4KIT supports Class 3 operation. Table 1 specifies two PSE input ranges: 42.5–57 V for up to 25.5 W and 37–57 V for up to 12.95 W - both within Class 3 limits. The Si34061 IC itself is IEEE 802.3bt-compliant and auto-negotiates power class with the PSE, making the SI34061FB12V4KIT suitable for interoperability testing across Class 3 and Class 4 deployments.