YB1506
Step-up DC-DC Converter , White LED Driver
Description
The YB1506 is a step-up(Boost) DC-DC
converter; operate as current source to drive
up to 5 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. The low off-time permits 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 YB1506 can drive up to 5 white LEDs
from a single Li-Ion battery DC 2.2V to 6.5V;
can be turn on by putting more than 1.2 volt
at pin 4 (SHDN). 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
SHDN pin.YB1506 has integrated Over
Voltage Protection that prevents damage to the
device in case of a high impedance output due
to faulty LED.
Features
Internal switch
Adjustable output voltage up to 22V
2.2V to 6.5V input range
0.1uA shutdown current
Small 5-Lead SOT-23 package
High efficiency
Drives 5 white LEDs
Over voltage protection
Applications
LCD Display Module
White LED Backlighting
PDAs
Digital Cameras
Portable Application
Cellular Phone
Electronic books
Typical Application Circuit (Li-Ion battery 2.5 volt to 6.5 volt is recommended.)
Figure 1:Typical Application Circuit
YB1506 MRev1.1
WWW.YOBON.COM.TW
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