NCP5050

NCP5050 4.5 W Flash White LED Boost Driver The NCP5050 is a high powered fixed frequency PWM boost converter optimized for constant current applications such as driving high−powered white LEDs. This device has been designed with high−efficiency for use in portable applications and is capable of driving up to 5 high power LEDs in series for camera flash or flashlight (torch) applications. To support the need of driving the LEDs in a high current pulse mode for flash as well as a continuous mode for focus or torch, a control pin and support circuitry is incorporated which allows the user to program two LED currents. The both output current are fully configurable via the use of 2 external resistors and this average current can be reduced by applying a PWM signal to the CTRL pin up to 50 kHz. The PWM operates at 1.7 MHz which allows the use of small inductors and ceramic capacitors. In addition the compensation is internal to the device which simplifies the design and reduces the PCB component count. To protect the device cycle−by−cycle current limiting and a thermal shutdown circuit have been incorporated as well as output over−voltage and time out protection. The maximum peak current level of the power switch is adjustable to allow further system optimization. The NCP5050 is housed in a low profile space efficient 3x3 mm thermally enhanced WDFN. Features High Efficiency Up to 88% for 2 LED (VF = 3.5 V by LED) at 200 mA High frequency Dimming PWM Control Maximum Vout of...