The LD7550BL is a low start-up current, current mode PWM controller manufactured by Leadtrend Technology. It is specifically designed for high-performance, low standby power consumption switching power supplies. This controller is suitable for applications such as AC/DC adapters, open frame power supplies, and LCD monitor power supplies.

Applications

• AC/DC Adapters: Regulating power for electronic devices such as laptops, smartphones, and tablets.
• Open Frame Power Supplies: Providing regulated power in various electronic equipment.
• LCD Monitor Power Supplies: Driving the backlight and other circuits in LCD monitors.
• Standby Power Supplies: Minimizing power consumption in standby mode for various appliances.
• Battery Chargers: Optimizing the charging process in various battery-powered devices.

Features

• Low Start-up Current: Reduces power consumption during the startup phase.
• Current Mode PWM Control: Offers improved line regulation and load regulation.
• Leading Edge Blanking: Filters out noise during the MOSFET turn-on period.
• Frequency Jittering: Reduces EMI (Electromagnetic Interference) emissions.
• Over Voltage Protection (OVP): Protects the circuit from excessive voltage.
• Over Current Protection (OCP): Limits the current to prevent damage from overcurrent conditions.
• Short Circuit Protection (SCP): Shuts down the controller during short circuit events.
• Under Voltage Lockout (UVLO): Ensures proper operation during low voltage conditions.

Benefits

• High Efficiency: Optimized for power conversion efficiency.
• Low EMI: Frequency jittering helps reduce electromagnetic interference.
• Robust Protection: Integrated protection features enhance reliability.
• Low Standby Power: Meets stringent energy efficiency standards.
• Cost-Effective: Provides a high-performance solution at a competitive price.

Additional Details

The LD7550BL PWM controller is designed to meet the rigorous demands of modern power supplies, providing excellent performance and comprehensive protection. Its low standby power consumption makes it suitable for energy-efficient applications. It is commonly used in flyback converter designs.

Technical Specifications:

• Operating Voltage Range: Typically 8V to 28V (Consult Datasheet)
• Switching Frequency: 65 kHz (Typical)
• Start-up Current: Very low, usually in the microampere range.
• Operating Temperature Range: -40°C to +85°C
• Package: SOT-26