ZXLD1362 LED Driver

Operating from a 6 V to 60 V input supply and achieving up to 95% efficiency, the ZXLD1362 from Diodes, Inc. can drive up to 16 high power LEDs with an adjustable output current of up to 1 A. Provided in the tiny TSOT23-5 package, this LED driver is the smallest of its kind in its current rating, with a maximum footprint of 2.8 mm x 2.9 mm and an off-board height of 1 mm.

Simple to use and requiring just four external components, this highly integrated chip supports a range of flexible LED brightness and thermal management schemes. Output current can be adjusted by applying either PWM or DC voltage control signals to the adjust pin. Application of a low voltage signal turns the output off and puts the device into a low current standby mode.

Supporting an operating frequency of up to 1 MHz, the ZXLD1362 is able to offer highly sensitive and accurate LED brightness control, with a typical dimming ratio of 1000:1 cited at 300 Hz. A soft-start feature can also be achieved by the addition of an external capacitor. Integrating a 60 V MOS switch and a high-side output current sensing circuit, which uses an external resistor to set the nominal output current, the chip enables high power LEDs to benefit from ground referenced return paths, of particular importance in architectural lighting applications.

To simplify thermal control, the input resistance of the chip's adjust pin has been set at 50 kΩ in order to be compatible with common thermistor values. The chip's compact design and ability to comfortably withstand high-voltage transients, means it will also appeal to space-starved automotive and industrial applications.