YB1508 Datasheet | YOBON TECHNOLOGIES

.. Step-up DC-DC Converter , White LED Driver Features - - - - - - - - - Description The YB1508 is a step-up DC-DC converter, acting as current source to drive up to 8 white LEDs in series. Series connecting of the LEDs provides identical LED currents resulting in uniform brightness and eliminating the need for ballast resistors. The light intensity of these LEDs is proportional to the current passing through them. Additional Features include output over voltage protection to prevent device damage due to faulty LED or open circuit caused by abnormal conditions, and one-pin shutdown and multiple methods of dimming control. The YB1508 switches at a fixed frequency of 1MHz, allowing the use of tiny external ponents and low input noise and ripple. To control LED brightness, the LED current can be pulsed by applying a PWM (pulse width modulated) signal with a frequency range of 100Hz to 50KHz to the CTRL pin. The YB1508 is available in a low profile 5-lead SOT-23 package. 2.7V to 9V input range Adjustable output voltage up to 40V Built in internal switch Inherently matched LED current Fixed frequency of 1MHz PWM operation Open LED protection Low profile 5-Lead SOT-23 package High efficiency: over 80% at 3.6V input voltage Drives up to 8 white LEDs Applications - - - - - - LCD Display Module OLED panel/sub-panel White LED Backlighting Digital Camera Cellular Phone Portable Application Typical Application Circuit Figure 1：Typical Application Circuit YB1508 MRev1.4 .YOBON..TW 1 .. Step-up DC-DC Converter , White LED Driver Pin Description Figure 2：YB1508 SOT23-5 Pin Designator Table 1 : Pin 1 2 3 4 5 Name SW GND FB CTRL VIN Description Switching Pin. This is the collector of the internal NPN power switch. Connect to inductor and diode. Minimize the metal trace area connected to this pin to reduce EMI. Ground Pin. Connect directly to local ground plane. Feedback Pin. Reference voltage is 200m V. Connect...