Texas Instruments LM3444

Description

The LM3444 is an adaptive constant off-time AC/DC buck (step-down) constant current controller that provides a constant current for illuminating high power LEDs. The high frequency capable architecture allows the use of small external passive components. A passive PFC circuit ensures good power factor by drawing current directly from the line for most of the cycle, and provides a constant positive voltage to the buck regulator. Additional features include thermal shutdown, current limit and VCC under-voltagelockout. The LM3444 is available in a low profile 10- pin VSSOP package or an 8-lead SOIC package.

Features

• Application Voltage Range 80VAC – 277VAC
• Capable of Controlling LED Currents Greater than 1A
• Adjustable Switching Frequency
• Low Quiescent Current
• Adaptive Programmable Off-time Allows for Constant Ripple Current
• Thermal Shutdown
• No 120Hz Flicker
• Low Profile 10-Pin VSSOP Package or 8-Lead SOIC Package
• Patent Pending Drive Architecture

Remarks:

L1=L2=3.9mh is used as input signal

Typical applications

• Solid State Lighting
• Industrial and Commercial Lighting
• Residential Lighting

More information

• Datasheet
• IC product information