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YB1518 Datasheet, PDF (1/12 Pages) YOBON TECHNOLOGIES,INC. – Step-up DC-DC Converter White LED Driver
YB1518
Step-up DC-DC Converter White LED Driver
Description
Features
The YB1518 is a step-up DC-DC converter;
operates as current source to drive up to 6
white LEDs(VIN at 3.0V) or 8 LEDs(VIN at
3.5V) or 9 LEDs(VIN at 3.5V) 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. The YB1518 switches at a
fixed frequency of ~930KHz, 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.
The YB1518 can drive up to 9 white LEDs
from a single Li-Ion battery. The wide input
voltage range from 2.7V to 7V is ideal for
portable applications with higher
conversion efficiency. 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
1KHz to the CTRL pin.
YB1518 has integrated Latched Over
Voltage Protection that prevents damage to
the device in case of a high impedance
output due to faulty LED or open circuit
caused by abnormal conditions.
„ Built-in internal switch
„ 2.7V to 7V input range
„ <1uA shutdown current
„ PWM dimming control 100Hz to 1KHz
„ Analog dimming control
„ Internal Soft Start
„ Drives up to 9 white LEDs(VIN at 3.5V)
„ Over voltage protection 34V
„ Small 5-Lead SOT-23 package
„ 100mV Low Reference Voltage
Applications
„ LCD Display Module
„ White LED Backlighting
„ PDAs, GPS terminals
„ Digital Cameras
„ Cellular Phone
„ Electronic Books
„ Portable Applications
Typical Application Circuit
Figure 1: Typical Application Circuit
YB1518 Rev.1.3
www.yobon.com.tw
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