PC112.pdf 데이터시트 (총 14 페이지) - 파일 다운로드 PC112 데이타시트 다운로드

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PC112/PC113
Version : A.001
Issue Date : 2004/10/01
File Name : SP-PC112/PC113-A.001.doc
Total Pages: 14
Step Up Converter for White LED Driver
新竹市科學園區展業一路 9 號 7 樓之 1
SILICON TOUCH TECHNOLOGY INC.
9-7F-1, Prosperity Road I, Science Based Industrial Park,
Hsin-Chu, Taiwan 300, R.O.C.
Tel886-3-5645656 Fax886-3-5645626

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點晶科技股份有限公司
SILICON TOUCH TECHNOLOGY INC.
PC112/PC113
General Description
PC112/PC113 is a compact, high-efficiency step-up DC-DC converter which drives
2-6 series white LEDs with constant current from 3V to 5V. Extremely low shutdown
power supply current ensures the high efficiency of battery system. The PC113 works
at 500KHz, allowing the application of tiny external components. Low feedback voltage
and hence minimal input current from the battery extends battery life.
Built-in N-channel power switches optimize the layout area of PCB. Since
PC112/PC113 drives series LEDs, it regulates the light intensity uniformly. With a single
external resistor or PWM signal, users can easily set the LED current and LED
brightness.
While output loading is open, likes the case of LEDs failure, the duty cycle of the
DC-DC converter will increase rapidly, causing high output voltage to damage the
circuit. To avoid this situation, a Zener diode should be connected to the DC-DC
converter’s output to clamp the output voltage in most applications. However, PC113
has built-in the over-voltage protection circuit to protect the output circuit and thus
eliminates the need of the external Zener diode.
PC112/PC113 is also characterized of the soft-start feature, which limits the inrush
current. It is available in Thin-SOT type package.
Features
1. Typical 85% efficiency
2. No external power switch
3. Low shutdown supply current
4. Low feedback voltage
5. Drives 6 white LEDs 20mA from working voltage 2.0V
6. ±4 % LED output current accuracy
7. Over voltage protection circuit build in(PC113)
8. Soft-start circuit build in
9. Thin 6-pin SOT23-6 package
Application
1. White LED Display Backlighting
2. Cellular Telephones
3. Personal Digital Assistant
4. Digital Cameras
5. Portable Machine
-1 - VersionA.001

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點晶科技股份有限公司
SILICON TOUCH TECHNOLOGY INC.
PC112/PC113
Block Diagram
LX
1
VSS
2
Soft
Start
Pre-
Driver
OVP
5
VDD
Clock
Genertor
5
OVP
PC113
FB
3
-
+
0.1V
Control
Logic
4
EN
Pin Descriptions
LX
1
VSS
2
FB
3
Pre
Driver
0.5V
Soft Clock
Start Genertor
5
VDD
PC112
Control
Logic
4
EN
Pin No
PC113 PC112
11
22
33
44
5
65
PIN NAME
LX
VSS
FB
EN
OVP
VDD
Descriptions
Connect inductor to battery
Ground pin
Feedback pin
Enable pin
Over voltage protection
Input voltage supply pin
1 LX SiTI VDD 6
2 VSS PC113 OVP 5
3 FB
EN 4
TopView
1 LX SiTI VDD 5
2 VSS PC112
3 FB
EN 4
-2 - VersionA.001

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點晶科技股份有限公司
SILICON TOUCH TECHNOLOGY INC.
Absolute Maximum Ratings
PC112/PC113
Parameter
Supply Voltage
LX Voltage
EN Voltage
Power Dissipation
Storage Temperature
Operating Temperature
Junction Temperature
Symbol
VDD
VLX
VEN
Pd
Tstg
Topr
TJ
Rating
5.5
24
5.5
2.5
-65~140
-40~120
160
Unit
V
V
V
mW
oC
oC
oC
Electrical characteristics, VDD=3.6V, Ta = 25 oC . (unless otherwise specified)
PARAMETER
SYMBOL
Operating Input Voltage VDD
CONDITION
FB PIN Voltage
VFB
FB Vol. Temp. Coefficient
Switch-on Resistance
TFB
RSW
ILED = 20mA
Switch Max On-time
Maximum Duty Cycle
Switching Frequency
Efficiency
TON
DMAX
FSW
η
Supply Current
IDD
IDDQ
VEN=High
VEN=Low
Shutdown Input Current
IEN VEN=High
VEN=Low
*Over voltage protection
VP
MIN TYP MAX Unit
2.8 3.6 5
V
85 95 105 mV
+92 µV/°C
1.5
1.4 1.5 1.6 µS
80 %
450 500 550 KHz
85 %
1 mA
0.1 µA
0.2 mA
10 nA
23 V
*Note1 : Only PC113 build this function
-3 - VersionA.001

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點晶科技股份有限公司
SILICON TOUCH TECHNOLOGY INC.
Typical application circuit
VIN
2.8 to 5.0V
IIN
L1
6.8uH
D1
MBR0520
C1
4.7uF
R1
22Ω
C2
4.7uF VDD
SiTI
LX
PC112 FB
ON
EN
OFF VSS
Zener
R3
1KΩ
C3
1uF
R2
5.6Ω
PC112/PC113
Fig. 1 Application circuit of PC112
VIN
2.8 to 5.0V
IIN
L1
6.8uH
D1
MBR0520
C1
4.7uF
ON
R1
22Ω
C2
4.7uF VDD
EN
OFF
SiTI
PC113
LX
OVP
FB
VSS
White
LED
x3
ILED
20mA
C3
1uF
R2
5.6Ω
Fig. 2 Application circuit of PC113
-4 - VersionA.001