STMicroelectronics EVLVIPER28H-10W

Overview

EVLVIPER28H-10W from STMicroelectronics is a high-voltage AC-DC converter evaluation board built around the VIPER28HN IC - an integrated 800 V avalanche-rugged power MOSFET with PWM current-mode control, 115 kHz switching frequency (H-type), 30 mW no-load consumption at 230 Vac, and dual-level overcurrent protection. It delivers up to 10 W continuous output in open-frame configurations for auxiliary power supplies.

For engineers reviewing the EVLVIPER28H-10W datasheet, EVLVIPER28H-10W pinout, EVLVIPER28H-10W application, or EVLVIPER28H-10W equivalent, this board enables rapid validation of VIPER28H-based flyback designs targeting energy metering, smart home adapters, and low-power industrial auxiliary rails - with full access to CONT, FB, EPT, and DRAIN nodes for real-time tuning and fault analysis.

Technical Context

The EVLVIPER28H-10W implements a complete 10 W flyback reference design using the VIPER28HN (DIP-7 package) operating at 115 kHz nominal frequency with ±8 kHz jitter modulation. It integrates HV startup via DRAIN pin, soft-start (8.5 ms typical), and burst-mode operation below 0.6 V on FB to achieve ≤30 mW no-load input power at 230 Vac.

Protection architecture includes cycle-by-cycle OCP (IDlim = 0.8 A typ.), second-level OCP (IDMAX = 1.2 A), digital-filtered output overvoltage protection (VOVP = 3.0 V ±0.3 V), thermal shutdown (TSD = 155 °C), and Extra Power Timer (EPT) with external capacitor timing for sustained overload handling up to 2 seconds.

Key Specifications

Availability

EVLVIPER28H-10W is available at Aetrix Electronics and suitable for energy metering, smart home auxiliary rails, and industrial IoT sensor node power supplies requiring stable component supply, fast design validation, and compliance-ready reference implementation.

Supply support for EVLVIPER28H-10W 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, power ICs, analog chips, and MEMS sensors for industrial, automotive, and consumer applications.

The VIPER® family - including EVLVIPER28H-10W - is engineered specifically for cost-sensitive, high-reliability AC-DC offline converters in auxiliary and adapter applications where integration, low no-load power, and robust protection are critical.

FAQ

What is the purpose of the EPT pin on the EVLVIPER28H-10W evaluation board?

The EPT (Extra Power Timer) pin connects to an external capacitor that sets a programmable delay (typically 1–2 seconds) during overload conditions. When triggered, it temporarily raises the OCP threshold to allow brief peak loads - such as motor startup or communication burst - without immediate shutdown, enabling reliable operation in intermittent high-power scenarios like smart meter data transmission.

Can the EVLVIPER28H-10W operate across universal AC input (85–265 Vac)?

Yes. The board leverages the VIPER28HN's 800 V avalanche-rugged MOSFET and HV startup circuit (enabled above 80 V DC on DRAIN), eliminating the need for an auxiliary winding. This allows direct operation from 85–265 Vac inputs while maintaining regulation, efficiency, and protection integrity across the full range - verified per IEC 61000-4-5 surge and EN 61000-3-2 harmonic standards.

How does burst-mode operation reduce no-load power on this board?

Burst-mode activation occurs when FB voltage drops below 0.6 V (typ.), causing the controller to gate pulses in discrete bursts rather than continuous PWM. This reduces average switching losses and quiescent current draw, achieving 30 mW no-load input power at 230 Vac - confirmed by measurements in ST's DocID15028 Rev 6, Figure 25 and Table 2 - meeting EU CoC Tier 2 and DOE Level VI requirements.

Is the EVLVIPER28H-10W compatible with both VIPER28HN and VIPER28HD variants?

No. The EVLVIPER28H-10W is specifically designed for the VIPER28HN (DIP-7 package, 115 kHz H-type). While VIPER28HD uses SO16 narrow packaging and shares functional blocks, its pinout, thermal layout, and PCB footprint differ significantly - requiring separate board revisions. ST does not endorse cross-package substitution on this evaluation platform without redesign and revalidation.