STMicroelectronics EVAL6599-400W-S

Overview

EVAL6599-400W-S from STMicroelectronics is an evaluation board for the L6599 high-voltage resonant half-bridge controller IC, designed to demonstrate 400 W LLC or series-resonant DC-DC conversion with soft-switching operation. It implements a complete 600 V-rated half-bridge power stage with integrated gate drivers, programmable frequency control (58–500 kHz), dual-level overcurrent protection, and PFC interface capability. The board supports real-time tuning of soft-start, burst-mode threshold, and line-sensing thresholds for AC-DC adapter and open-frame SMPS validation.

For engineers reviewing the EVAL6599-400W-S datasheet, EVAL6599-400W-S pinout, EVAL6599-400W-S application, or EVAL6599-400W-S equivalent, this board enables rapid prototyping of high-efficiency resonant converters targeting LCD/PDP TV power supplies, telecom rectifiers, and server auxiliary power stages - with direct access to all L6599 control pins, bootstrap circuitry, and current-sense interface points.

Technical Context

The EVAL6599-400W-S implements the L6599's fixed 50 % complementary duty cycle control logic with programmable dead-time (0.2–0.4 µs) to enforce zero-voltage switching in LLC topologies. Its oscillator uses external R_Fmin and C_F to set minimum frequency (58.2–61.8 kHz typ.) and supports full-range frequency shift during non-linear soft-start.

Board-level protection includes two-stage OCP: first-level frequency-shift response triggered at 0.8 V on ISEN (50 mV hysteresis), and second-level latched shutdown at 1.5 V; plus line-sensing (1.25 V threshold), latched DIS input (>1.85 V), and PFC_STOP open-drain output synchronized with fault events.

Key Specifications

Availability

EVAL6599-400W-S is available at Aetrix Electronics and suitable for LCD TV power supply development, telecom SMPS qualification, and AC-DC adapter reference design requiring stable component supply and full functional validation of resonant control architecture.

Supply support for EVAL6599-400W-S 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, specializing in power management, analog, microcontrollers, and automotive-grade ICs with ISO 9001 and IATF 16949 certified manufacturing.

The L6599 product line was developed specifically for high-efficiency resonant half-bridge DC-DC conversion in consumer and industrial power supplies, emphasizing soft-switching reliability, integrated 600 V gate drive, and multi-level fault protection for 200–1000 W applications.

FAQ

What input voltage range does EVAL6599-400W-S support?

The board is configured for universal AC input (85–265 VAC) with active PFC front-end compatibility. Its L6599 controller accepts 12–16 V DC bias on VCC and supports up to 618 V floating supply on VBOOT. Input rectification and bulk capacitance are pre-installed; no modification is needed for standard offline operation.

Can EVAL6599-400W-S be used with LLC or series-resonant tanks interchangeably?

Yes - the board's transformer and resonant capacitor values are optimized for LLC operation but can be reconfigured for series-resonant mode by adjusting L_r/C_r ratios and retuning R_Fmin. The L6599's variable-frequency control and fixed dead-time inherently support both topologies without firmware change.

How is burst-mode behavior adjusted on this evaluation board?

Burst-mode threshold is set by resistor divider on the STBY pin (Pin 5), referenced to internal 1.25 V comparator. Default configuration enables burst at ~20 % load; users adjust the divider ratio to raise or lower activation point. No additional components are required - only resistor value changes on the STBY network.

Does EVAL6599-400W-S include thermal monitoring or overtemperature protection?

No dedicated OTP circuit is onboard; protection relies on L6599's existing functions: DIS pin can be tied to external thermistor circuitry (e.g., NTC + comparator) to trigger latched shutdown above 150 °C junction temperature. Board layout includes thermal pads and test points for IR camera verification of MOSFET and controller die temperatures.