The SD6835 is a highly integrated quasi-resonant (QR) flyback converter designed by Silan Microelectronics. It is specifically engineered for high-performance offline flyback converter applications, offering features that contribute to improved efficiency, reliability, and overall system cost-effectiveness.

Applications:

• Power adapters for mobile phones and other portable devices.
• Open-frame power supplies for consumer electronics.
• Standby power supplies for televisions and set-top boxes.
• LED lighting power supplies.
• Auxiliary power supplies in industrial equipment.

Features:

• Quasi-Resonant (QR) Operation: Operates in QR mode to minimize switching losses and improve overall efficiency.
• Integrated High-Voltage Startup: Eliminates the need for external startup resistors, reducing component count and improving efficiency.
• Frequency Fold-Back: Reduces switching frequency at light load conditions to further improve efficiency.
• Valley Switching: Minimizes switching losses by turning on the MOSFET at the valley of the drain-source voltage.
• Brown-Out Protection: Protects the power supply from damage due to low input voltage conditions.
• Over-Voltage Protection (OVP): Prevents output voltage from exceeding a safe level.
• Over-Current Protection (OCP): Limits the output current to protect the power supply and load from damage.
• Over-Temperature Protection (OTP): Shuts down the power supply in the event of excessive temperature.
• Short-Circuit Protection (SCP): Protects the power supply from damage due to a short circuit at the output.
• Open-Loop Protection: Protects the system from damage due to open-loop conditions.

Benefits:

• High Efficiency: QR operation and frequency fold-back contribute to high efficiency across a wide load range.
• Reduced Component Count: Integrated startup and protection features reduce the number of external components required, simplifying the design and reducing the cost.
• Improved Reliability: Comprehensive protection features ensure reliable operation in various operating conditions.
• Simplified Design: The highly integrated nature of the SD6835 simplifies the design process.
• Cost-Effective: Reduces overall system cost due to the integration and high efficiency.

The SD6835 employs advanced control techniques to achieve high performance and reliability. The QR operation minimizes EMI (electromagnetic interference) and reduces stress on the MOSFET. The integrated protection features ensure safe operation under various fault conditions. The device is typically available in a DIP-8 or SOP-8 package.