The LM5035BMHX is a high-performance PWM controller designed for half-bridge resonant converters. Manufactured by Texas Instruments (formerly National Semiconductor), this controller integrates all the necessary features to implement a robust and efficient power supply. It is primarily used in applications requiring high efficiency and power density.

Applications

• Isolated DC-DC Converters
• Half-Bridge Resonant Power Supplies
• Telecom Power Supplies
• Server Power Supplies
• Industrial Power Supplies

Features

• Resonant Mode Operation: Enables high efficiency and low EMI.
• Integrated High-Side and Low-Side Drivers: Simplifies design and reduces component count.
• Programmable Switching Frequency: Allows optimization for specific applications.
• Adjustable Dead-Time: Enables fine-tuning of the resonant circuit.
• Over-Voltage Protection (OVP): Protects the power supply from over-voltage conditions.
• Over-Current Protection (OCP): Protects the power supply from over-current conditions.
• Under-Voltage Lockout (UVLO): Prevents operation at low input voltages.
• Soft-Start: Reduces stress on components during startup.
• Synchronization Capability: Allows multiple power supplies to be synchronized.

Benefits

• High Efficiency: Resonant mode operation minimizes switching losses, resulting in high efficiency.
• Reduced EMI: Resonant mode operation reduces electromagnetic interference.
• Simplified Design: Integrated features simplify design and reduce component count.
• Robust Protection: Over-voltage, over-current, and under-voltage protection ensure reliable operation.
• Flexible Operation: Programmable switching frequency and adjustable dead-time allow optimization for various applications.
• Improved Reliability: Soft-start reduces stress on components during startup, improving reliability.

Additional Details

The LM5035BMHX typically operates with an external resonant inductor and capacitor to form the resonant circuit. The controller regulates the output voltage by adjusting the switching frequency. Careful attention must be paid to the selection of external components to ensure proper operation and stability. The datasheet provides detailed guidelines for component selection and PCB layout. The controller also includes a fault reporting feature that signals the occurrence of over-voltage, over-current, or under-voltage conditions.