Catalyst released for the high power 2W backlight applications LED

Catalyst semiconductor company launched a new application based on high power 2W backlight LED driver (Watt). CAT4240 boost converter provides up to 750mA switching current and 38V output voltage, suitable for driving a variety of backlight applications - from a single string of 1W LED to multi series of low power LED.

CAT4240 can provide 2W output power when the 3V-5V power supply; when using a separate power supply, through a higher 9V to 12V power supply up to 5W of output power. In addition, the circuit design of low noise and high switching frequency of the device also integrates all functions required by the application, the user does not have to realize the soft start and overvoltage protection using additional external components, greatly reduces the noise and saves space on the circuit board. The high output voltage of the boost converter mostly uses a simple frequency variable design. This approach will lead to a wide range of redundant harmonics, the user is not easy to be filtered or eliminated; CAT4240 using a fixed frequency switching circuit architecture (1MHz), is the ideal choice for low noise applications. In addition, the device is built in high voltage CMOS output stage, can be driven in a low input voltage state of a long string (the total voltage value of up to 38V) is accurately offset and voltage LED, conversion efficiency can be as high as 87%.

In order to eliminate the excess inrush current (in-rush) generated during power up, CAT4240 integrates the soft start control circuit. In case of LED open circuit failure, the CAT4240's internal overvoltage protection circuit forces the device into a low power mode, limiting the output voltage to a safe level without any peripheral devices. The above two characteristics have been fully integrated, without the need to increase external components and related costs, but also save the board space.

Designers in the use of CAT4240 can choose DC voltage, logic signal or PWM (pulse width modulation) signal to control the brightness of LED. Product features

drive high voltage LED series, voltage up to 38V switch current limit 750mA

1MHz fixed frequency low noise operation complete protection function

5 pin SOT23 thin package (max height 1mm) supply and price

With 10000 meter, CAT4240 LED drive unit price of $0.84. Sample available now. The delivery time is 6 ~ 8 weeks after receipt of order.