YB1520.pdf 데이터시트 (총 18 페이지) - 파일 다운로드 YB1520 데이타시트 다운로드

No Preview Available !

www.DataSheet4U.com
YB1520
High Power Step-up DC-DC Converter, White LED Driver
Description
Features
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.
Typical Application Circuit
„ 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
YB1520 MRev.1.2
Figure 1: Typical Application Circuit
www.yobon.com.tw
1

No Preview Available !

www.DataSheet4U.com
Pin Configuration
YB1520
High Power Step-up DC-DC Converter, White LED Driver
Pin Description
Table 1
Pin
NAME
1 SW
2 GND
3 FB
4 CTRL
5 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 200mV. Connect LEDs
and a resistor at this pin. LED current is determined by the
resistance and CTRL voltage.
Shutdown Pin and Dimming Control pin.
VCTRL > 1.8V generates full-scale LED current
VCTRL < 0.4V chip is off
Switching from 0.4V to 2.0V, PWM duty cycle controls the LED
current
Input Supply Pin. Bypass this pin with a capacitor as close to
the device as possible
Ordering Information
Order Number
YB1520ST25
Supplied as
3000 units Tape & Reel
Package Marking
Y52M
YB1520 MRev.1.2
www.yobon.com.tw
2

No Preview Available !

www.DataSheet4U.com
YB1520
High Power Step-up DC-DC Converter, White LED Driver
Absolute Maximum Ratings
Recommended Operating Conditions
Vin .......................................................................... 20V
SW Voltage ............................................................36V
FB Voltage ...............................................................5V
CTRL Voltage...........................................................5V
Maximum Junction Temp, TJ (not 2)...................150°C
Lead Temperature (Soldering 10 sec) ................300°C
Thermal Resistance............................................195°C
Operating Temperature (note 3) ................ –40°C~85°C
Supply Voltage............................................. 2.5V~16V
SW Voltage ............................................................30V
Electricity Characteristics
(TA=25°C, Vin=3.3V, Cin=1uF Cout=10uF unless otherwise noted)
Symbol
Vin
IQ
(Quiescent
Current)
VFB
ICL
ILIM
IB
FRSW
Function Parameter
Input Voltage Range
Not Switching
Shutdown
Feedback Voltage
Switch Current Limit
FB Pin Bias Current
Switching Frequency
Test Conditions
Vfb = 0.3V
CTRL = 0V
Iout=20mA,Vout=12.5V
Circuit of Figure 1
100% Duty Cycle
40% Duty Cycle
Vfb=200mV
Min
2.7
1.2
180
850
2
680
Typ Max Units
16 V
1.5 1.7 mA
0.3 1
uA
200 220 mV
900 950
600
mA
mA
10 20
uA
700 720 KHz
DTMX
DTMN
VSAT
ILKG
VCTL
ICTL
OVP
θJA
Maximum Duty Cycle
Minimum Duty Cycle
Switch Vcesat
Switch Leakage Current
VCTRL for Full LED
Current
CTRL Pin Bias Current
Over Voltage Protection
Thermal Resistance
At Isw = 200mA
Ctrl = 0.3V
Full On
Full Off
Ctrl = 2V
20
120
1
1.7
0.2
20
34
220
85 %
25 %
mV
μA
1.8 V
0.3 V
μA
V
°C/W
Note:
Absolute maximum ratings are limits beyond which damage to the device may occur. The maximum allowable power dissipation is a
function of maximum function temperature, TJ(max), the junction to ambient thermal resistance, θJA , and the ambient temperature.
The maximum allowable, power dissipation at any ambient temperature is calculated using: PD(MAX)= [TJ(max)-TA]/θJA . Exceeding
the maximum allowable power dissipation will cause excessive die temperature. All limits at temperature extremes are guaranteed via
correlation using standard statistical methods
YB1520 MRev.1.2
www.yobon.com.tw
3