Half of the country launched a new white LED driver LM3530

National Semiconductor Corporation Ns (National Semiconductor Corporation, NS) announced the launch of the industry's smallest white LED driver, you can control the display backlight brightness. This model LM3530 step-up converter belongs to the national semiconductor PowerWise high efficiency chip series, can drive high current LED up to 11 series, can provide sufficient for large screen backlight intelligent mobile phone and other portable multimedia electronic products. LM3530 chip using 12 solder ball micro SMD package, the entire chip size is only 1.615mm * 1.215mm * 0.425mm size.

Because the multimedia content of portable electronic products is becoming more and more colorful, the display screen is more and more big. Accordingly, this also caused a substantial increase in power consumption problem. National Semiconductor's LM3530 LED driver uses an advanced ambient light detection algorithm, and can be adjusted according to the video content backlight brightness. Compared with the common brightness constant backlight system, the LM3530 system is not only clear and bright, but also can save up to 50% of power consumption.

National semiconductor has 3.5 inches iPod touch display backlight system for power consumption test. The test was divided into two groups, one group using the national semiconductor LM3530 LED drive, while the control group did not use this drive.

The video content used in the test is a collection of some of the most common multimedia video data from the Internet, such as one episode of a TV series, and a trailer for a movie. The test results show that the power consumption of the backlight system using the LM3530 chip is less, and compared with the traditional backlight system, the power consumption is reduced by 43% and 55%, respectively. Because of the film trailer in the dark screen more, the backlight is less, so the energy saving effect is more obvious.

technical specifications

The national semiconductor LM3530 current mode boost converter can use a lithium battery for 11 white LED to provide up to 29.5mA drive current. System design engineers can use I2C compatible interface set a variety of light effect function, for example, to the external environment and the level of illumination and brightness and image effect.

LM3530 chip can also set the ambient light response time, and has a separate PWM dimming input function. So this LED backlight driver can be flexible according to actual conditions determine the backlight brightness required, and then choose different dimming scheme, so as to provide the actual environment of different light output the most suitable. The chip uses a logarithmic function and linear LED brightness mapping technology to ensure that when the flicker does not flicker. LM3530 boost converter uses a fixed 500kHz frequency, so as long as the LED current does not exceed the specified range, its efficiency can be maintained at a high level.

If the LM3530 chip is used as the driver, the system can reduce the power consumption of the large screen display backlight system which is connected in series LED. For the use of parallel charge pump display, the United States National Semiconductor will be launched in October 2009 with another feature similar products.

Prices and availability

U.S. National Semiconductor LM3530 chip to 1000 units for the purchase of a single price of $1.99, has begun to bulk supply.