NS introduced a new generation of high brightness LED driver products

National Semiconductor (National Semiconductor NS) to launch a new series of light emitting diode (LED) driver can drive characteristics of automotive electronic system, industrial system and general lighting system built a new generation of 1W to 5W high brightness leds. NS these light-emitting diode drive models are LM3402, LM3404 and LM3405, the advantage is that the input voltage range is wider, can meet the requirements of this high growth market.

In addition NS this series of new light emitting diode driver can not only output constant current, to ensure that the brightness of the light-emitting diode uniform, and the feedback voltage is low, the power consumption can be reduced to a minimum. The LM3402 LED driver has two different versions, both of which have a wide input voltage (6V to 42V or 6V to 75V), and the two versions are capable of driving the 1W light emitting diode. LM3404 and LM3405 two chips can output a more powerful drive current, it is suitable for driving 3W and 5W led.

LM3402 is a compact fixed current step-down regulator, efficiency of up to 95%, can output up to 525mA drive current. The chip uses a mini 8 pin SOIC package, one of which allows the pin to use pulse width modulation (PWM) input signal to control the light dark. In addition, the chip can be used as low as 0.2V feedback voltage to provide current sensing function. The LM3402 chip can be operated by using the input voltage 6V to 42V; LM3402HV chip is another suitable for high input voltage of the types of products, not only applicable voltage range from 6V to 75V, and the function is identical to LM3402.

LM3404 and LM3404HV chip are 8 pin narrow SOIC package, its function is not the same as LM3402 and LM3402HV chips, but the LM3404 and LM3404HV chip can output up to 1.2A of the drive current. These two products can provide 700mA or 1A drive current for 3W and 5W leds.

LM3405 constant current constant current buck regulator with 8 pin Mini SOIC package, and a small 6 pin SOT-23 package available, this feature is the current chip can output up to 1A, using LED driver 3W or 5W. The chip can not only use the 0.2V reference voltage to provide constant current feedback control function, and the switching frequency can also be internally set to 550kHz or 1.6MHz, for system using light emitting diode driver for this solution is simple and high efficiency. In addition, the LM3405 is suitable for 3V to 22V input voltage range, and can provide internal compensation, but also through the light / dark pin, pulse width modulation dimming control.

LM3402 and LM3402HV chip has begun mass production. Samples of LM3404 and LM3404HV wafers have also been supplied and are scheduled for mass production in November. LM3405 chip samples will be available for customer orders in November, and in the beginning of January 2007 there are mass production.