PT4103-White LED Step-Up Converter SOT23-6 0VP30V

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PT4103:

● 小尺寸SOT23-6封装

● 输出具有30V过压保护

● 工作电压为2.5-6V

● 恒流驱动白光LED

● 输入电压2.5V时可驱动3V的白光LED 五颗串联

● 输入电压3.6V时可驱动3V的白光LED 八颗串联

● 效率高达87%

● 1.2MHZ固定的开关频率

● 超低的0.104V的采样电压

● 负载开路关断功能

● 软启动功能

GENERAL DESCRIPTION

The PT4103 is a step-up DC/DC converter designed for driving up to 8 white LEDs in series from a single cell Lithium Ion battery with constant current. Because it directly regulates output current, the PT4103 is ideal for driving light emitting diodes (LEDs) whose light intensity is proportional to the current passing through them, not the voltage across their terminals. A single external resistor sets LED current between 5mA and 20mA, which can then be easily adjusted using either a DC voltage or a pulse width modulated (PWM) signal. Its low 104mV feedback voltage reduces power loss and improves efficiency. The OV pin monitors the output voltage and turns off the converter if an over-voltage condition is present due to an open circuit condition. The PT4103 is available in SOT23-6 packages.

FEATURES

l Drives Up to 5 Series White LEDs from 2.5V

l Drives Up to 8 Series White LEDs from 3.6V

l Up to 87% Efficiency

l 1.2MHz Fixed Switching Frequency

l Low 104mV Feedback Voltage

l Open Load Shutdown

l Soft Start/PWM Dimming

l SOT23-6 Packages

APPLICATIONS

l Cell Phones

l Handheld Computers and PDAs

l Digital Cameras

l Small LCD Displays

TYPICAL APPLICATIONS