LY9526 Current Mode PWM Controller

The LY9526 is a current-mode PWM (Pulse Width Modulation) controller IC commonly used in switch-mode power supply (SMPS) designs. It provides precise voltage regulation by adjusting the duty cycle of the switching signal based on feedback from the output voltage and current.

 Features:

1. Current-Mode Control – Improves loop stability and provides inherent cycle-by-cycle current limiting.

2. Wide Input Voltage Range – Typically supports a broad range of input voltages for various power supply designs.

3. Adjustable Switching Frequency – Allows flexibility in design optimization for efficiency and noise reduction.

4. Under-Voltage Lockout (UVLO) – Ensures proper startup and shutdown behavior.

5. Soft-Start Function – Reduces inrush current during startup.

6. Over-Current Protection (OCP) – Protects the circuit from excessive current.

7. Over-Voltage Protection (OVP) – Safeguards against output voltage spikes.

8. Thermal Shutdown – Prevents damage due to overheating.

Applications:

• AC/DC power supplies

• DC/DC converters

• LED drivers

• Battery chargers

• Adapters and industrial power systems

Pin Configuration:

Design Considerations:

• Feedback Loop Compensation: Proper compensation is needed for stability.

• Current Sensing: Use a low-ohm resistor or transformer for accurate current feedback.

• Thermal Management: Ensure adequate heat dissipation if operating at high power.