STMicroelectronics EVL6591-90WADP

Overview

EVL6591-90WADP from STMicroelectronics is a 90 W evaluation board implementing the L6591 double-ended PWM controller for zero-voltage-switching (ZVS) half-bridge AC-DC power supplies. It delivers complementary gate drive with programmable deadtime up to 500 kHz, integrates 600 V-rail compatible high-side and low-side drivers, and supports adaptive UVLO, pulse-by-pulse OCP, transformer saturation detection, and PFC interface - validated for high-efficiency desktop PC and telecom SMPS designs.

For engineers reviewing the EVL6591-90WADP datasheet, EVL6591-90WADP pinout, EVL6591-90WADP application, or EVL6591-90WADP equivalent, this page provides verified board-level specifications, functional architecture, thermal and layout guidance, supply chain availability, and manufacturer context - all aligned with ST's production-grade reference design Doc ID 14821 Rev 6.

Technical Context

The EVL6591-90WADP implements a soft-switched half-bridge topology using the L6591 IC, where high-side and low-side MOSFETs are driven complementarily with digitally clipped ≤50% duty cycle and externally programmable deadtime via OSC pin capacitor. The board integrates an onboard high-voltage startup generator (HVSTART pin), synchronous bootstrap diode (BOOT/FGND/HVG), and line-sensing circuitry for brownout protection and power-on sequencing.

It enables burst-mode operation at light load via COMP pin voltage thresholding (1.75 V turn-on / 1.68 V turn-off), supports latched shutdown via DIS input (>4.5 V), and interfaces directly with PFC controllers through open-drain PFC_STOP output. Transformer saturation detection is implemented via ISEN pin hiccup-mode OCP at 1.5 V, while adaptive UVLO adjusts Vcc thresholds based on loading conditions.

Key Specifications

Availability

EVL6591-90WADP is available at Aetrix Electronics and suitable for desktop PC power supplies, telecom SMPS development, and high-efficiency AC-DC adapter/charger prototyping requiring stable component supply, full documentation traceability, and production-aligned reference design validation.

Supply support for EVL6591-90WADP 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, designing and manufacturing analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer applications.

The EVL6591-90WADP belongs to ST's Power Management Evaluation Board product line, engineered to accelerate adoption of their ZVS half-bridge controllers - specifically targeting energy-efficient, high-power-density offline SMPS designs compliant with EU CoC Tier 2 and ENERGY STAR® requirements.

FAQ

What is the primary function of the EVL6591-90WADP evaluation board?

The EVL6591-90WADP is a fully assembled, tested 90 W reference design board demonstrating the L6591 PWM controller in a ZVS half-bridge AC-DC converter. It validates soft-switching performance, thermal behavior, protection response, and PFC interoperability - not a standalone IC but a complete subsystem for rapid system-level evaluation and layout verification.

Does EVL6591-90WADP support universal AC input (90–264 VAC)?

Yes - the board is designed for universal input operation (90–264 VAC) with automatic adaptation via the LINE sensing circuit (pin 1), which triggers shutdown below 1.25 V and enables brownout recovery. Input rectification, bulk capacitance, and EMI filtering are included per ST's validated schematic in Doc ID 14821.

Can the deadtime be adjusted on this board, and how?

Yes - deadtime is set by the timing capacitor connected to the OSC pin (pin 5); typical value is 330 pF for ~180 kHz oscillator frequency, yielding ~500 kHz switching with 0.42–1.0 µs deadtime depending on capacitor value. The board includes test points and footprint options for capacitor replacement to fine-tune ZVS margin across load and line conditions.

Is the high-side gate driver isolated, and what is its floating voltage rating?

Yes - the high-side driver uses a bootstrap configuration referenced to FGND (pin 13), with BOOT (pin 15) supplying the floating rail. The L6591 IC supports up to 618 V on BOOT relative to FGND and withstands dV/dt up to 50 V/ns on FGND - confirmed by ST's absolute maximum ratings (Table 2) and validated in the EVL6591-90WADP layout with creepage-compliant spacing.