Designed to drive 0.5 watts of LEDs at 150mA to 200mA typical current, these LED drivers provide longer LED lifetimes and a digital interface for pulse width modulation (PWM) signals for dimming Use when lighting.
The new BCR320 and BCR420 LED drivers are tailored to address the shortcomings of 0.5 watt LED applications, and are not only compact, but also extremely low cost and simple solutions. With these two devices, the use of inductors, capacitors, and free-whe EL ing diodes can be eliminated, which not only saves cost, but also helps reduce PCB space requirements. Eliminating the use of electrolytic capacitors also helps to extend the life of the LED system.
The LED Driver Family BCR320 is designed for peak output currents up to 300mA. The maximum rated current is recommended to be 250mA for continuous operation. Although the internal breakdown voltage of this device is generally 20V, it can operate at a supply voltage of 24V or higher due to the use of a driver in series with the LED.
The BCR320 is designed for general lighting, architectural and atmospheric lighting applications. The BCR320 device has a negative temperature coefficient and once the temperature increases, the current will decrease at a slope of 0.2%/K. The BCR320U and BCR321U are available in a very compact SC-74 package (2.9mm x 2.5mm x 1.1mm) and consume 1W. The BCR320P and BCR321P models are available in 2W higher power and SOT-223 packages (6.5mm x 7.0mm x 1.6mm). Both the BCR321U and BCR321P versions can dim the light with a logic level input.
Compared to the BCR320 device, the BCR420 product has a higher internal breakdown voltage and a lower output current. Its internal breakdown voltage is typically 50V and the rated output current is 150mA. The BCR420 LED has a maximum drive current of 150mA and is also designed for these applications. It is currently applying for automotive applications that meet the AECQ 101 standard. The BCR420 and BCR421 products are currently available in the SC-74 package. The BCR421 adjustable dark version driver has a microcontroller interface.
The BCR320U and BCR420U LED drivers are in volume production; the BCR320P and BCR321P are expected to enter mass production in the first quarter of 2010. 
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