Auto Electronics

National Semi LED drivers offer wide input voltage range

National Semiconductor has added two light-emitting diode (LED) drivers to its PowerWise product family. The LM3401 and LM3405A power 1 W to 5 W, high-brightness LEDs in automotive and other applications.

The LM3401 features a voltage range from 4.5 V to 35 V, a scalable current drive of greater than >3A, and a 100% duty cycle. A low feedback voltage of 0.2 V and accuracy within 3% provides a constant current to provide constant color output from an LED.

The LM3405A has a 3 V to 22 V range and can regulate from a loosely coupled 12 V ac rail. Its SOT-23 package allows LEDs to be placed into small-form factor lightbulbs to offer higher efficiency vs. traditional halogen and incandescent sources.

Separately, National announced WEBENCH, an online LED design environment that helps engineers select from and design with more than 200 high-brightness LEDs from six different suppliers. It’s available at

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