Preliminary YB1510
Step-up DC-DC Converter,White LED Driver
Description
The YB1510 is a step-up DC-DC converter;
operates as current source to drive up to 7
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 YB1510 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 YB1510 can drive up to 7 white LEDs
from a single Li-Ion battery. 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.
YB1510 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 7 white LEDs
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
EFFICIENCY
85
80
EFFICIENCY (%)
75
Vin=3.6V
Vin=4.2V
70
65
60
55
Figure 1: Typical Application Circuit
0
5
10
15
20
LED CURRENT (mA)
YB1510 MRev.0.4
WWW.yobon.com.tw
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