LM2753SDX

The LM2753 is capable of driving a flash LED with a pulsed current of 400 mA at an input voltage of 3.6 V. A switched-capacitor doubler, the LM2753 provides a regulated 5-V output (VOUT) over an input supply range of 3 V to 5.5 V. The switched output, IOUT, takes less than 10 ns to turn on and provide maximum current to a flash LED. Flash LED current is set via a ballast resistor. Continuous illumination current (torch mode) is programmed by connecting a resistor between IOUT and VOUT. This device uses only three small, low-cost ceramic capacitors.The LM2753 device uses pulse frequency modulation (PFM) regulation. Typical operating frequency is 725 kHz. Under no-load conditions, the LM2753 operates on only 60 µA. If the output is connected to ground, the charge pump stays in the gain of 1, which helps limit the input current to 300 mA (typical).