Description
The STCF05 is a high efficiency power supply solution to drive multiple flash LEDs in camera phones, PDAs and other hand-held devices. The synchronous boost topology with output current control guarantees the proper LED current over all possible conditions of battery level and LED forward voltage. All the functions of the device are controlled through the I²C bus that allows to reduce logic pins on the package and to save PCB traces on the board. Hard and soft-triggering of the flash are both supported. The device includes many functions to protect the chip and the power LEDs. These comprehend a soft-start control, chip over temperature detection and protection, open and shorted LEDs detection and protection. In addition, a digital programmable time-out function protects the LEDs in case of wrong command from microprocessor. See description (continued). TFBGA25 (3 x 3 mm)

Features
■ Boost DC-DC converter with synchronous rectification
■ Drives 2 power white LEDs in series with a current up to 400 mA
■ Input voltage range 2.5 V to 5.5 V
■ Needs 3 external components only
■ Output current control
■ 1.8 MHz fixed frequency PWM control
■ Peak inductor current limited to 3 A
■ Full I²C control
■ Operational modes: – Standby mode – Standby mode with NTC – Flash mode: up to 400 mA – Torch mode: up to 120 mA
■ Soft and hard triggering of flash
■ Flash and Torch dimming in 15 exponential steps
■ Dimmable red LED indicator auxiliary output
■ Internally or externally timed flash operation
■ Digitally programmable safety time-out in flash mode
■ LED overtemperature detection and protection with external NTC resistor
■ Open and shorted LED failure detection and protection
■ Chip overtemperature detection and protection
■ Less than 1 µA standby current

Applications
■ Cell phones and smartphones
■ Camera flashes/strobe
■ PDAs and digital still cameras