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    Parts    LNK304DN-TL
LNK304DN-TL

LNK304DN-TL

Power Integrations
Converter Offline Buck, Buck-Boost, Flyback Topology 66kHz SO-8C
Active221,153 in stock
Datasheet Digi-Key Mouser Compare Prices

Overview

The LNK304DN-TL is a LinkSwitch-TN off-line switcher IC designed for low-cost, non-isolated power supplies. It integrates a 700V power MOSFET, oscillator, and a simple ON/OFF control scheme onto a single monolithic die. This component is optimized for buck, buck-boost, and flyback topologies, providing a high-efficiency alternative to linear regulators and passive dropper solutions.

Why Choose This Part

This IC reduces component count by eliminating the need for a transformer in buck configurations and using a simple inductor instead. It features built-in frequency jittering to lower EMI and includes comprehensive protection features such as cycle-by-cycle current limiting and hysteretic thermal shutdown. The wide input voltage range supports universal AC mains from 85VAC to 265VAC.

Applications

Appliances and White Goods
Ideal for providing low-current DC power to timers, displays, and control logic in washing machines and dishwashers.
Smart Home Automation
Used in smart switches, dimmers, and motion sensors that require compact non-isolated power from AC mains.
LED Lighting Drivers
Supports constant-current LED drivers for small-scale residential or decorative lighting applications.
Industrial Auxiliary Supplies
Efficiently generates 5V or 12V rails for sensors and communication modules in industrial equipment.

Key Specifications

Topology Buck, Buck-Boost, Flyback
Duty Cycle 69%
Mounting Type Surface Mount
Package / Case 8-SOIC (0.154", 3.90mm Width), 7 Leads
Fault Protection Current Limiting, Open Loop, Over Temperature, Short Circuit
Output Isolation Non-Isolated
Internal Switch(s) Yes
Voltage - Breakdown 700V
Frequency - Switching 66kHz
Operating Temperature -40degC ~ 150degC (TJ)
Supplier Device Package SO-8C

Getting Started

Designers should use the PI Expert Suite software to automate the calculation of inductor and capacitor values for specific output requirements. When laying out the PCB, keep the power loops small and ensure the Source pins have sufficient copper area for heat sinking, as they serve as the thermal connection. Review the AN-37 application note for detailed guidance on EMI mitigation and thermal management.

Also Consider

LNK306DN-TL Power Integrations - Provides a higher output current capacity (up to 360mA in buck topology) while maintaining the same SO-8C footprint.
VIPer12A STMicroelectronics - An alternative off-line switcher with an integrated 730V MOSFET that is widely used in similar low-power buck or flyback applications.
UCC28881 TITexas Instruments - Features a 700V internal MOSFET and lower quiescent current, suitable for designs with very strict standby power requirements.