Low voltage led driver - Clare - #1

White LED Step-Up Converter with Linear Dimming Control

IXYS

• 1.1V to 5.5V Input Range

• 2 Amp Peak Switch Current

• High Efficiency > 80%

• 20V Maximum Output with Over-Voltage Protection

• LED Intensity Control

• 1.0 MHz Fixed Frequency Switching

• 8 Lead SOIC Package

• RoHS Compliant Product

• White LED Display Backlighting

- Low Voltage: Mobile Phones, PDA's,

MP3 Players, Digital Cameras

- High Drive Current:

Vehicle Instrumentation Panels

The MX841 is a fixed frequency, constant current source step-up DC/DC converter. The output current is directly regulated making the MX841 ideal for driving series connected white light emitting diodes (LED's) in backlight applications. The MX841 powers up to 3 series white LED's at 1.1V, and 20 series/parallel white LED's at 5.0V.

The MX841 features a 1.0MHz switching frequency to accommodate the use of small capacitors and a small inductor necessary in size sensitive portable applications. Light intensity and shutdown are conveniently controlled by a single analog voltage. Power efficiency and battery life are extended through the use of a high voltage, low R_dson N-channel MOSFET switch.

The MX841 is designed to operate over a temperature range of -40°C to +85°C, and is available in an SOIC-8 Package, with or without an Exposed Pad in Tube or on Tape and Reel. (Alternate package types available upon request).

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MX841

Drawing No. 17023

10/04/07 www.claremicronix.com