STCF01

STCF01 Step-up converter for cell phone camera flash LEDs General features ■ ■ ■ ■ ■ ■ ■ ■ ■ Supply voltage range: 2.6V to 5.5V 17V Maximum output voltage Two current levels up to 300mA set with external resistors Dedicated pin to select the required level of current Operating frequency: 1.5MHz: PWM Controller Torch mode supported Shutdown pin with true load disconnection Efficiency: 90% at 100mA; 80% at 300mA DFN10L (3mm x 3mm) Package to set the required current for each level. Compared to the linear current control technique, this method allows designers to achieve the best and most efficient performance possible with the selected current, thereby avoiding linear element losses. The Shutdown (SHDN) pin saves power when the camera flash is not used by consuming less than 0.1µA of current. When the SHDN pin is high (logic '1'), the device is turned OFF and there is no DC current path from the supply to the white LEDs (Load Disconnect). If it is held to GND, the output current continuously flows through the LEDs (Torch mode). The SHDN pin, when it is set to low (logic '0'), is also used to set the flash function time duration. DFN10L (3x3) Description The STCF01 is a dedicated IC designed to drive two, three, or four white, cell phone camera flash LEDs with constant current. The step-up (boost) converter input is connected directly to the battery, and its converter output voltage is automatically determined using current feedback-based duty cycle control. The STCF01 has a d...