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.

Key Features of LY9526:

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.

Typical Applications:

• AC/DC power supplies

• DC/DC converters

• LED drivers

• Battery chargers

• Adapters and industrial power systems

Pin Configuration (General Example – Verify with Datasheet):

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.