TS1937

Boost (Step-up) WLED Driver SOT-25 Pin Definition: 1. SW 2. Ground 3. Feedback 4. CTRL 5. Input www.DataSheet4U.com TS1937 General Description The TS1937 is a step-up DC/DC converter specifically designed to drive white LEDs with a constant current. The device can drive 2 ~ 12 LEDs in series from a Li-Ion cell. Series connection of the LEDs provides identical LED currents resulting in uniform brightness and eliminating the need for ballast resistors. The output capacitor can be as small as 0.22µF, saving space versus alternative solutions. A low 95mV feedback voltage minimizes power loss for better efficiency. Additional feature include over output voltage limiting when LEDs are disconnected. The TS1937 switches at a fixed frequency of 1.2MHz, allowing the use of tiny, low profile inductors and capacitors to minimize footprint and cost in space consideration applications for cellular phone backlighting or other hand held equipment. Features ● ● ● ● ● ● ● ● ● Inherently Matched LED Current High Efficiency: 88% Typical Drives Up to 6 LEDs @ Vin 5V Drives Up to 12 LEDs @ Vin 12~15V 36V Rugged Bipolar Switch Fast 1.2MHz Switching Frequency Requires Only 0.22µF Output Capacitor PWM dimming control 1KHz to 10KHz Analog dimming control Application ● ● ● ● ● Cellular Phones Digital Still Cameras MP3 Players White LED Backlighting PDAs, Handheld computers Ordering Information Part No. TS1937CX5 RF Package SOT-25 Packing 3Kpcs / 7” Reel Typical Application Circuit 1/8 ...