YB1520
High Power Step-up DC-DC Converter, White LED Driver
Description
The YB1520 is a step-up DC-DC converter;
operates as current source to drive up to 9
white LEDs in series or 30 white LEDs in
parallel/series configuration. 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 YB1520 switches at
a fixed frequency of 700KHz, 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 YB1520 can drive up to 9 white LEDs from
a single Li-Ion battery and drive up to 30 white
LEDs from a 5V. The wide input voltage range
from 2.7V to 16V is ideal for portable and
automotive (5V/12V) 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 50KHz to
the CTRL pin.
YB1520 has integrated 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.
Features
Built-in internal switch
Adjustable output voltage up to 35V
2.7V to 16V input range
<1uA shutdown current
High efficiency
Drives up to 30 white LEDs in
Parallel/series
Over voltage protection
Small 5-Lead SOT-23 package
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
YB1520 MRev.1.2
www.yobon.com.tw
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YOBON [ YOBON TECHNOLOGIES,INC. ]
