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Description

The LM5025B is a functional variant of the LM5025 active clamp PWM controller.

The functional differences of the LM5025B are as follows:

• The maximum PWM duty cycle is limited to less than 75% to reduce voltage stress on the power MOSFETs.
• The CS2 hiccup mode threshold is increased to 0.5V
• The CS2 filter discharge device is disabled
• The Vcc regulator continues to operate when the line UVLO is below the threshold of normal operation
• The Vref regulator is switched off when the line UVLO input falls below the operating threshold
• The internal 5kΩ COMP pin pull-up resistor is removed

Features

• Internal Start-Up Bias Regulator
• 3A Compound Main Gate Driver
• Programmable Line Under-Voltage Lockout (UVLO) with Adjustable Hysteresis
• Voltage Mode Control with Feed-Forward
• Adjustable Dual Mode Over-Current Protection
• Programmable Overlap or Deadtime between the Main and Active Clamp Outputs
• Volt x Second Maximum Duty Cycle Clamp
• Programmable Soft-Start
• Current Sense Leading Edge Blanking
• Single Resistor Programmable Oscillator
• Oscillator Up / Down Sync Capability
• Precision 5V Reference
• Thermal Shutdown