STMicroelectronics STEVAL-POE005V1

Overview

STEVAL-POE005V1 from STMicroelectronics is a reference design evaluation board implementing an IEEE 802.3bt-compliant Power over Ethernet (PoE) Powered Device interface and a 12 V / 8 A active clamp forward DC-DC converter. It integrates the PM8805 dual-active-bridge PoE-PD IC and PM8804 peak-current-mode PWM controller, supports 4-pair high-power PoE delivery up to 90 W, and delivers regulated 12 V output with >92% DC-DC efficiency at full load for building security and surveillance systems.

For engineers reviewing the STEVAL-POE005V1 datasheet, STEVAL-POE005V1 pinout, STEVAL-POE005V1 application, or STEVAL-POE005V1 equivalent, key selection considerations include IEEE 802.3bt classification capability, dual-active-bridge topology support, active clamp forward topology implementation, and compatibility with ST's PM8804/PM8805 ecosystem for medium-to-high-power PoE-powered applications.

Technical Context

The board implements a two-stage architecture: first, the PM8805 performs IEEE 802.3bt-compliant detection, classification (Classes 1–8), and power handshaking via dual active bridges and hot-swap MOSFETs; second, the PM8804 controls a synchronous active clamp forward converter operating up to 1 MHz with programmable soft-start, slope compensation, and dual complementary low-side gate drivers.

Input voltage range spans 52–57 V (PoE midspan/PSE compliant), with output regulation at 12 V ±1% across 0–8 A load. The design includes integrated RJ45 magnetics, common-mode chokes, input filtering, and auxiliary bias generation - all validated per IEC/EN 62368-1 safety requirements for Class II PoE-powered equipment.

Key Specifications

Availability

STEVAL-POE005V1 is available at Aetrix Electronics and suitable for building security systems, IP surveillance cameras, access control panels, and industrial IoT edge nodes requiring stable component supply and pre-validated IEEE 802.3bt PoE power conversion.

Supply support for STEVAL-POE005V1 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, analog ICs, power management devices, and sensors for automotive, industrial, and consumer markets.

This board belongs to ST's STEVAL (ST Evaluation) series - purpose-built reference designs that demonstrate complete, application-ready implementations of ST's power, interface, and control ICs for rapid prototyping and design-in validation.

FAQ

What is the maximum input power the STEVAL-POE005V1 can accept from a PSE?

The board accepts up to 90 W input power from an IEEE 802.3bt-compliant PSE, supporting Class 8 operation (up to 71.3 W delivered after PoE interface losses). Measured input power at J1 reaches 88.2 W under full 12 V / 8 A load, with PM8805's dual 100 V / 0.2 Ω active bridges limiting conduction loss to <1.2 W total.

Does the STEVAL-POE005V1 support legacy 2-pair (10/100BASE-T) PoE operation?

Yes - the PM8805 IC automatically detects and operates in legacy 2-pair mode when connected to IEEE 802.3af/at PSEs. Classification signals T0/T1/T2 indicate detected PSE type and class, and the board maintains full functionality including hot-swap control and auxiliary bias generation in both 2-pair and 4-pair configurations.

Can the output voltage be adjusted to 5 V or 24 V?

No - the board is fixed at 12 V output by resistor divider R119/R122 (4.7 kΩ / 20 kΩ) feeding the TL431 reference. To change output voltage, the feedback network must be recalculated and reworked; ST does not provide alternate BOM variants. The PM8804 supports adjustable output, but this board's layout and compensation are optimized exclusively for 12 V.

Is isolated auxiliary power provided for external circuitry?

Yes - an auxiliary 12 V rail (AUX) is derived from the main forward converter's auxiliary winding via D42, C82, and U22 (TS2431), delivering up to 150 mA. This rail powers optocouplers, monitoring ICs, and low-power peripherals without loading the main 12 V output, maintaining regulation accuracy and transient response.