Providing an adjustable output current of 1A from a SOT23 package, the ZXLD1360 LED driver from Zetex Semiconductors offers higher power density than SO8 devices. A buck regulator device, it operates over a supply range of 7V to 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% efficiency, this LED driver’s thermally enhanced construction combines with a high level of component integration to create LED lighting solutions. 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 input/output 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. Designed to be used in LED-based automotive, industrial, emergency and architectural lighting circuits and in general illumination applications, the ZXLD1360 is temperature rated over the range –40ºC to +125ºC and will handle transient voltage incursions of up to 40V. In the event of LEDs going open circuit, coil current flows via an external clamp diode to ensure the driver is protected from harm.
Pin-compatible with the well-established 350mA ZXLD1350 LED driver, the ZXLD1360 is to be followed later in the year by the introduction of a 60V, 1A driver (ZXLD1362) and a configurable driver, supporting buck, boost and buck/boost operating modes (ZXLD1380). For very simple low voltage LED indication applications, a single cell boost regulator is also due for release (the ZXSC380). Sampling now, the ZXLD1360 high power LED driver from Zetex Semiconductors is priced at $0.90 in 25k quantities.
