LED lighting driver delivers high power density
Posted : 07 May 2007

Providing an adjustable output current of 1A from an SOT23 package, the ZXLD1360 LED driver from Zetex Semiconductors promises higher power density than alternative and much-larger SO8 devices. A buck regulator device, it operates over a supply range of 7-30V and is capable of handling up to 24W of output power in a wide range of high-power LED illumination applications. Achieving up to 95 percent efficiency, this LED driver's thermally enhanced construction combines with a high level of component integration to create compact LED lighting solutions that are low in part count and simple to configure. The ZXLD1360 integrates a 30V NDMOS switch and a high-side current sensing circuit, which sets the average output current in relation to an external sense resistor. Where LED brightness control is required, the output current can be adjusted above or below the set value by applying an external DC voltage or PWM control signal to the ADJ pin. The driver's in-built PWM filter also provides a soft-start capability by controlling the rise of I/O current. Soft start time can be further increased using an external capacitor. Applying a low voltage to the ADJ pin turns the output off and puts the device into a low current standby mode.
From the website global sources EE Times Asia at http://www.eetasia.com/ART_8800463529_1034362_9e53a45a200705.HTM