GENERAL DESCRIPTION
Because it directly regulates output current, the PT4101 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 2mA and 20mA, which can then be easily adjusted using either a DC voltage or a pulse width modulated (PWM) signal up to 100KHz. The PT4101 is available in SOT23-6 packages. FEATURES
z z z z z z z Drives Up to 5 Series White LEDs from 3V Up to 87% Efficiency 1.25MHz Fixed Switching Frequency Low 104mV Feedback Voltage Open Load Shutdown PWM Dimming SOT23-6 Packages APPLICATIONS
z z z z Cell Phones Handheld Computers and PDAs Digital Cameras Small LCD Displays ORDERING INFORMATION PACKAGE SOT23-6 TEMPERATURE RANGE -40 oC to 85 oC ORDERING PART NUMBER PT4101B23F TRANSPORT MEDIA Tape and Reel 3000 units MARKING 4101 TYPICAL APPLICATIONS
0.89 Vin=3.6V 0.88 0.87 0.86 Efficiency 0.85 0.84 0.83 0.82 0.81 0.80 2mA 2*LED 3*LED 4*LED 5*LED 5mA 10mA 15mA 20mA Iout (mA) Figure 1.
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