L6591TR

AC DC Converters, Offline Switchers Overview

The L6591TR is a double-ended PWM controller designed for asymmetrical half-bridge converter topologies. It operates with a maximum switching frequency of 500 kHz and supports a maximum duty cycle of 50%. The device features a high-voltage floating structure capable of withstanding over 600 V, eliminating the need for an external bootstrap diode. Operating voltage ranges from 8.7 V to 22 V, with a startup voltage of 14 V. It functions within a temperature range of -40°C to +150°C TJ and is housed in a 16-SOIC package.

AC DC Converters, Offline Switchers Feature Summary

• Provides complementary PWM control with externally programmable deadtime to ensure soft-switching operation.
• Integrates a synchronous-driven high-voltage DMOS for high-side gate driving, replacing external components.
• Includes controlled burst mode operation at light loads to minimize mains consumption.
• Features adaptive UVLO to manage self-supply voltage fluctuations caused by transformer parasitics.

AC DC Converters, Offline Switchers Applications

• Asymmetrical half-bridge AC/DC converters
• High-frequency power supply designs
• Energy-efficient adapter systems

AC DC Converters, Offline Switchers Procurement Notes

Verify the specific suffix TR indicates tape and reel packaging when sourcing. Confirm RoHS compliance status through official STMicroelectronics documentation prior to integration. Ensure the 16-SOIC footprint matches the PCB layout requirements. Validate that the 600 V withstand capability aligns with the target circuit's voltage stress levels.

AC DC Converters, Offline Switchers Selection Notes

Select this component for applications requiring asymmetrical half-bridge topology with integrated high-side drive. The built-in burst mode suits strict energy efficiency standards. Consider the 500 kHz frequency limit for magnetics design. Verify compatibility with PFC controllers if used in two-stage systems via the provided interface.

AC DC Converters, Offline Switchers Part Context

The L6591 belongs to STMicroelectronics' family of AC/DC offline switch controllers. It is specifically engineered for soft-switched half-bridge applications. The TR variant denotes the reel packaging format. This IC addresses the need for reduced component count and improved efficiency in modern power adapters.

AC DC Converters, Offline Switchers Replacement Considerations

Public confirmed substitute part numbers are not available in the provided source material.

AC DC Converters, Offline Switchers FAQ

How does the L6591 handle high-side switching without an external diode?

It incorporates a synchronous-driven high-voltage DMOS that replaces the external fast-recovery bootstrap diode, allowing the IC to withstand more than 600 V.

What mechanism ensures soft-switching in the half-bridge topology?

An externally programmable deadtime inserted between the turn-off of one switch and the turn-on of the other guarantees soft-switching conditions.