ST STEVAL-DPSLLCK1

STEVAL-DPSLLCK1 is a digitally controlled 3kW full-bridge LLC resonant DC-DC converter with output synchronous rectification. The kit includes a power board, a digital control board, an adapter board, and firmware modules. The full-bridge primary stage of the LLC converter is based on MDmesh DM2 power MOSFETs for high-efficiency performance. The PWM switching frequency is regulated by digital control to adjust the output voltage; the converter operates near the resonant frequency to maximize efficiency and achieve zero-voltage switching (ZVS) across the entire operating range. A high-frequency transformer provides galvanic isolation and magnetic integration of inductive elements for a compact design. The secondary side employs STripFET F7 power MOSFETs for synchronous rectification (SR), reducing conduction losses. The STM32F334 microcontroller on the digital control board embeds a high-resolution timer for finer regulation, and can transmit status information via USART, CAN, SMBus, and optocoupler serial communication. Both the primary and secondary stages are powered by an offline flyback circuit based on the VIPer27HD, providing regulated voltages for the control board, gate driver ICs, and signal conditioning circuits.

• Input DC voltage range: 375V to 425V
• Output voltage: 48V
• Maximum output current: 62.5A
• Output power: 3kW
• Peak efficiency: 95.3%
• High-frequency transformer isolation voltage: 4kV
• Maximum DC-DC switching frequency: 380kHz (at startup)
• Closed-loop switching frequency range: 120kHz to 250kHz
• Resonant frequency: 175kHz
• Input and output undervoltage and overvoltage protection
• Overtemperature and short-circuit protection
• Forced cooling with airflow speed regulation based on output power and temperature
• Adaptive synchronous rectification
• Light-load burst mode
• Digital control via STM32F334 microcontroller