LM5025CSD

• Internally activated bias regulator
• 3A composite front door driver
• Programmable Line Adjustable Hysteresis Undervoltage Lockout (UVLO)
• With feedforward voltage mode control
• Adjustable dual-mode overcurrent protection
• Programmable primary and active clamp outputs between overlaps or dead zones
• Volt x two pincers
• Programmable soft start
• Cutting-edge erasing
• Single-resistor programmable oscillator
• Oscillator up/down synchronization function
• Precision 5V reference
• Thermal shutdown

illustrate

LM5025C is the functional variation of the LM5025's active clamping PWM controller. LM5025C the functional difference is that the maximum duty cycle of LM5025C has increased from 80% to 91%. Increase in charge current for soft-start capacitors from 20μA to 90μA. The current limit threshold for V CC regulators from 25 mA to 55 mA is increased. The current limit threshold for CS1 and CS2 has been increased to 0.5V. The internal CS2 filter discharge device has been disabled and no longer operates every clock cycle. The internal regulators of the V CC and V REF continue to operate when the line UVLO pin falls below the threshold.

LM5025C PWM controller contains all the necessary functions to implement the power converter, utilizing active clamping/reset technology. Active clamping technology, higher efficiency and greater power density, enables clamping/reset techniques compared to traditional catch-up windings or RDCs. Two control outputs are available, Main Power Switch Control (OUT_A) and Active Clamp Switch Control (OUT_B). Two internal composite gate drivers connect the MOS and bipolar devices in parallel to provide superior gate drive characteristics. The controller is designed for high-speed operation and includes an oscillator with a frequency range of up to 1MHz and a total PWM and current-sensing propagation delay of less than 100 ns. LM5025C includes a high-voltage start-up regulator that exceeds the wide input range of 13V to 90V. Other features include: Line Undervoltage Lockout (UVLO), Soft Start, Oscillating Up/Down Synchronization Function, Precise Reference, and Thermal Shutdown.