STMicroelectronics EVL170W-FTV

Overview

EVL170W-FTV from STMicroelectronics is a 170 W demonstration board for flat-panel TV power supplies, implementing a three-stage architecture: transition-mode PFC (L6564), LLC resonant half-bridge (L6599A), and flyback standby (Viper27LN). It delivers regulated 5 V/2 A, 12 V/2 A, and 24 V/6 A outputs with >90% full-load efficiency and <150 mW standby consumption at 230 Vac.

For engineers reviewing the EVL170W-FTV datasheet, EVL170W-FTV application, EVL170W-FTV bill of materials, or EVL170W-FTV design reference, this board provides a validated, ENERGY STAR®-compliant topology for wide-input (90–264 Vac), high-efficiency TV and industrial SMPS development with EN61000-3-2 Class-D harmonic compliance and EN55022 Class-B EMI performance.

Technical Context

The board integrates ST's L6564 PFC controller in transition mode to generate a stable 400 V DC bus, which feeds both the L6599A-controlled LLC resonant converter and the Viper27LN-based 5 V/2 A flyback standby supply. The PFC stage enables >0.99 power factor and EN61000-3-2 Class-D compliance across universal AC input (90–264 Vac, 45–65 Hz).

L6599A drives the LLC half-bridge with fixed 50% duty cycle and variable frequency (30–130 kHz), using integrated magnetics where primary leakage inductance serves as series resonant inductor and magnetizing inductance as shunt resonant inductor. Output regulation employs weighted feedback via TL431 and optocoupler, with cross-regulation between 12 V and 24 V rails.

Key Specifications

Availability

EVL170W-FTV is available at Aetrix Electronics and suitable for flat-panel TV power design, industrial auxiliary supply validation, and energy-efficient SMPS prototyping requiring stable component supply, reference-grade thermal layout, and pre-verified EMI filtering.

Supply support for EVL170W-FTV 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, specializing in power management, analog, microcontrollers, and automotive ICs with vertical manufacturing and application-focused design centers.

This evaluation board belongs to ST's Power Supply Reference Design portfolio, engineered to accelerate time-to-market for high-efficiency, regulatory-compliant AC-DC converters targeting consumer displays and industrial power systems.

FAQ

What is the purpose of the secondary ground signal on EVL170W-FTV?

The secondary ground signal acts as a system-level enable/disable control for the PFC and LLC stages. It is driven by the TV microprocessor and interfaces via optocoupler U5 to activate Q7, which supplies 14 V bias to L6564 and L6599A only when asserted high-ensuring safe, sequenced startup and shutdown.

How does the EVL170W-FTV achieve cross-regulation between its 12 V and 24 V outputs?

Cross-regulation is implemented via a weighted feedback network that combines voltage dividers from both 12 V and 24 V rails into a single TL431 reference node. This single-point regulation loop, closed through optocoupler U5, maintains ±3% tolerance on 12 V and ±5% on 24 V under dynamic load transitions without separate error amplifiers.

Does EVL170W-FTV include brownout protection, and how is it implemented?

Yes-brownout protection is dual-redundant: the Viper27LN monitors AC input via its BROWNOUT pin, while the L6564 uses its internal VFF pin comparator to detect mains peak voltage. Both disable operation below ~80 Vac, preventing unstable startup or erratic behavior during low-line conditions.

Can the EVL170W-FTV be modified for non-TV applications such as industrial 24 V systems?

Yes-the board's 24 V/6 A output, universal input, and robust LLC stage make it adaptable for industrial 24 V DC power systems. Modifications would include removing the 5 V standby section, adjusting feedback resistors for tighter 24 V tolerance, and verifying thermal derating for continuous 144 W output in non-ventilated enclosures.