Vishay launched a white LED driver with multiple protection features

The day before, Vishay Intertechnology, Inc. announced the launch of two new 1.25MHz current mode boost converter for white LED application and optimization. The new SiP12510 and SiP12511 devices have the input voltage range of 2.5V to 6.0V, the output voltage of SiP12510 is 17V, the maximum of SiP12511 is 28V.

These two new devices using SOT23-6 package provides a minimum of external components required for small LED driver solutions. Both SiP12510 and SiP12511 are equipped with an internal integrated power switch and operate on the 1.25MHz high frequency conversion oscillator. This allows the use of small inductors, thereby reducing the required board space.

This comprehensive LED driver solution incorporates a variety of protection features, including over voltage protection as well as 0.55A cycle by cycle current limit, up to three parallel strings, each 20mA. By closing the device when the internal temperature exceeds a typical temperature threshold of 165 DEG C, the thermal shutdown block provides another protective layer.

In order to realize the full control of the LED luminous intensity, SiP12510 and SiP12511 can be used to support the LED and PWM technology. By gradually increasing the switching current limit, the built-in three-phase soft start function can reduce the peak current required during startup.

Each device has a low 0.1V feedback voltage and a tight switching frequency, which can achieve a higher conversion efficiency in the entire operating temperature range of -40 DEG C to +85 DEG C.

Due to the combination of efficiency, less than 90% of the 1 A turn off current and small occupying area, portable application of SiP12510 and SiP12511 is especially suitable for limited space and battery power, such as mobile phone, PDA and digital camera.

At present, the new SiP12510 and SiP12511 samples have been available, mass production will be available in the second quarter of 2007, bulk orders supply cycle for 13 weeks.

Source: EE