KDR720E [KEC]
White LED Step-Up Converter; 白光LED升压转换器
| 型号： | KDR720E |
| 厂家： | 
KEC(KOREA ELECTRONICS) |
| 描述： | White LED Step-Up Converter |
| 文件： | 总7页 (文件大小：411K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
SEMICONDUCTOR
KAB3403T/DN
BICD LINEAR INTEGRATED CIRCUIT
TECHNICAL DATA
White LED Step-Up Converter
The KAB3403T/DN is a monolithic step-up DC/DC converter specifically
designed to drive white LEDs with a constant current from Li-ion cell.
Relative large 320mV feedback voltage & it s high accuracy help you
setting LED current with a external resistor.
E
K
1
B
K
6
DIM MILLIMETERS
_
A
B
C
D
E
2.9+0.2
KAB3403T/DN is available in a extremely low profile & small TS-6
package.
1.6+0.2/-0.1
_
0.70+0.05
2
5
_
+
0.4 0.1
A 10 H inductor is sufficient for most application.
2.8+0.2/-0.3
3
4
_
F
G
H
I
1.9+0.2
0.95
FEATURES
_
0.16+0.05
0.00-0.10
0.25+0.25/-0.15
0.60
Inherently Matched LED Current.
High Efficiency : 87% (max.)
J
K
L
0.55
Built in a open circuits protection for the LEDs fail.
Drives Up to Five LEDs
I
H
J
J
Built in a N-channel MOSFET Switch.
Fast 1.1MHz(typ.) Switching Frequency.
Wide Dimming control range : 12%~100%.
Automatic Soft-Start
TS6
Bulit in OVD (Over voltage protection.)
Extremely low height & small Packaging.
APPLICATIONS
Celluar Phones
A
B
Smart Phones
PDAs
A
Digital Cameras
MP3 Players, Color Displays
G
D
C
DIM MILLIMETERS
_
A
B
C
D
E
F
+
2.00 0.10
_
1.60
0.30
+
0.10
0.05
_
+
0.65 Typ
_
+
_
+
1.00
0.10
0.25
0.10
Φ 0.25
G
H
I
Marking
_
0.75 0.05
+
0.0 + 0.05
0.20 Ref
6
1
5
4
3
Lot No.
J
Type Name
Lot No.
Type Name
40033
403
TDFN-6
2
KAB3403DN
KAB3403T
2007. 2. 26
Revision No : 0
1/7
KAB3403T/DN
TYPICAL APPLICATION
CONVERSION EFFICIENCY
L1
4.7µH ~ 22µH
D1
V
OUT
V
IN
90
85
80
75
70
65
60
LED1
C1
1µF
V
SW
OVD
CC
LED2
LED3
LED4
C2
1µF
KAB3403T/DN
ON
OFF
CTL
FB
V
FB
3.0V
Shutdown and
Dimming control
GND
3.6V
4.3V
5.0V
R1
16Ω
0
5
10
15
20
25
30
35
LOAD CURRENT (mA)
BLOCK DIAGRAM
V
CC
SW
OVD
I sens
Comparator
OVER
R
Q
Driver
VOLTAGE
S
DETECTION
Ramp
Generator
1.1MHz
Oscillator
GND
FB
Soft
Start
Error
Amp
Reference
Generator
(320mV)
V
ref
Dimming
CTL
Shutdown
figure 2. KAB3403T/DN Block Diagram
PIN FUNCTIONS
NO.
SYMBOL
FUNCTION AND CONNECTION.
KAB3403T KAB3403DN
VCC
GND
FB
6
5
4
3
2
1
2
3
4
5
Input supply pin. Must be locally bypassed.
Ground pin. Connect directly to local ground plane,
Feedback pin. Reference voltage is 320mV. Connect cathode of lowest LED and resistor here.
Switch pin. Connect inductor/diode here. Minimize trace area at this pin to reduce EMI.
Over output voltage detect pin. Connect cathode of schottky diode and anode of highest LED.
SW
OVD
Control pin : Shutdown or dimming control. Connect external enable or dimming circuits.
Shutdown mode (IF = 0) : VCTL<1.0V
1
6
CTL
Dimming control mode : (IF = 12% ~ 100%, depend on VCTL
)
2007. 2. 26
Revision No : 0
2/7
KAB3403T/DN
MAXIMUM RATINGS (Ta=25
)
CHARACTERISTICS
SYMBOL
VCC
RATING
-0.3 ~ 6.0
-0.3 ~ 22
-0.3 ~ 22
-40 ~ 85
-55 ~ 150
150
UNIT
V
Input Voltage
VSW
Switching pin Voltage
V
VOVD
Topr
Tstg
OVD pin Voltage
V
Operating temperature range
Storage temperature range
Maximum Junction temperature
Tj
RECOMMENDED OPERATING CONDITIONS (Topr=-40~85
)
CHARACTERISTICS
Input Voltage
SYMBOL
VCC
CONDITION
MIN.
2.7
2.7
-
TYP.
MAX.
5.5
-
UNIT
-
-
-
-
V
V
V
VCTL
VCTL
H
L
CTL pin voltage for full LED current
CTL pin voltage to shutdown chip
VCC=3.0V
0.5
VCC=3.6V, RSENSE=16
Topr =25 , Five LED
,
LED Current
IF
-
20
-
-
-
CTL Response Delay
(When Power ON.)
Tpd CTL
-
2
ELECTRICAL CHARACTERISTIC
(Topr=-40~85 , VCC=2.7~5.5V, RSENSE=16 , unless otherwise noted.)
CHARACTERISTICS
Input Voltage
SYMBOL
VCC
CONDITION
-
MIN. TYP. MAX. UNIT
2.7
-
0.9
0.5
320
5
5.5
1.5
1
V
VCC = 3.6V, VCTL=3.6V
-
-
ICC
Supply Current
VCTL = 0V
VFB
ICTL
Feedback Voltage
304
-
336
10
1.43
-
VCC=VCTL=3.0V, Topr = 25 , L =4.7 H
VCC = 3.0V, VCTL = 3.0V
VCTL = 3.0V
CTL Pin Bias Current
Switching Frequency
fOSC
0.77
-
1.1
400
0.5
21
0.5
-
IO(SW)
IOZ(SW)
VOVD
IOZ(OVD)
VO(SW)
VCTL H
VCTL L
IFB
Switching Pin Current
Switch Leak Current
-
-
1
OVD Pin Voltage
-
19
-
23
1
V
VOVD = 18V
OVD Pin Leak Current
Switching Pin OVP
-
25
2.7
-
-
V
V
V
CTL pin voltage for Full LED Current
CTL pin voltage to shutdown Chip
Feedback Bias Current
Maximum Duty Cycle
-
-
VCC = 3.0V
-
0.5
1
-
-
-
0.5
90
Dmax
85
-
%
2007. 2. 26
Revision No : 0
3/7
KAB3403T/DN
Inductor Section
The KAB3403T/DN will then switch at a high duty cycle resulting
in a high output voltage. But Internal Over Voltage Protection
Circuits prevent output voltage ascending over OVD pin
voltage(19V ~ 23V see Fig 4). This circuits is valid when driving
up to 4 LEDs in series. But, when driving more than 4 LEDs in
series, Normal output voltage could be over OVD pin voltage. In
this case, zener diode can be used to check connect of OVD pin to
LED anode.(see Fig 5) [Recommended Zener diode : KDZ3.0V]
A 10uH inductor is sufficient for most application. The efficiency
comparision of different value inductors help you design your
application circuits.
90
88
VIN=3.6, 4LED Inductor=Murata
86
84
82
80
78
76
74
72
70
68
66
L1
D1
4.7µH ~ 22µH
V
IN
LED1
10µH
4.7µH
64
62
60
V
SW
OVD
CC
LED2
LED3
LED4
0
5
10
15
20
25
30
35
C2
1µF
KAB3403T/DN
LOAD CURRENT (mA)
Figure3. Efficiency Comparison of different value inductors
CTL
FB
GND
C1
1µF
Inductor Section
R1
16Ω
A 1uF input capacitor and output capacitor above 1uF are
sufficient for most KAB3403T/DN application.
Diode Selection
Figure4. 4LEDs driver with Open-circuit protection.
For Diode Selection, both forward voltage drop and diode
capacitance need to be considered. Schottky diodes with higher
current ratings usually have lower forward voltage and larger diode
capacitance, which can cause significant switching losses. A
schottky diode rated at 100mA to 200mA is sufficient for most
KAB3403T/DN applications.
L1
D1
4.7µH~22µH
V
IN
LED1
LED2
LED3
LED4
LED5
LED6
V
SW
OVD
CC
C2
1µF
Reverse
Forward
Voltage
KAB3403T/DN
Part No.
Package
Voltage (V) Current (mA) Drop (V)
CTL
1.60
1.20
0.6V (max)
FB
KDR730E
30
30
20
200 mA
200 mA
500 mA
GND
at 200 mA
C1
1µF
R1
16Ω
1.60
1.20
0.5V(max)
at 200 mA
KDR720E
KDR412
2.50
1.70
0.5V(max)
at 500 mA
Figure5. 6LEDs driver with Open-circuit protection.
Table1. Recommended Schottky Diode
Dimming Control
There are 4 different type of dimming control circuits;
LED Current Control
The LED current is controlled by the feedback resistor (RSENSE
in Figure 1). The feedback reference is 320mV. The LED current
is 320mV/RSENSE . The tolerance of LED Current is depends on
tolerance of RSENSE and feedback reference.
1. Using a DC Voltage to CTL pin
VCTL
Description
UNIT
VCTL>2.5V
0V~0.5V 1V~2.5V
Rate Of the LED Current
Example : RSENSE = 16
0
0
25 ~ 100
5 ~ 20
100
20
%
Open-Circuits Protection
mA
In the case of output open circuit, when LEDs are disconnected
from the circuit or the LEDs fail, the feedback voltage will be zero.
Table 2 CTL pin Voltage vs ILED
2007. 2. 26
Revision No : 0
4/7
KAB3403T/DN
4. Using a Logic Signal to FB pin.
L1
D1
4.7µH ~ 22µH
For application that need to adjust the LED current in discrete
steps. A logic signal can be used as shown in Figure 9.
V
IN
LED1
LED2
LED3
LED4
V
SW
OVD
CC
L1
C1
1µF
D1
4.7µH ~ 22µH
C2
V
IN
1µF
KAB3403T/DN
LED1
DC
V
SW
OVD
CC
CTL
FB
LED2
LED3
GND
R1
16Ω
C2
1µF
KAB3403T/DN
LED4
R1
CTL
KTK5132V
FB
LOGIC
Figure6. Using a DC Signal to CTL pin.
2. Using a filtered PWM Signal to CTL pin.
GND
C1
1µF
The filtered PWM signal can be considered as an adjustable DC
voltage. It can be used to replace the variable DC Voltage source
in dimming control. The circuit is shown in Figure 7
Figure9. Using a Logic Signal to FB pin.
L1
4.7µH ~ 22µH
D1
V
IN
LED1
LED2
LED3
LED4
C1
1µF
V
CC
SW
OVD
C2
1µF
KAB3403T/DN
R1
15kΩ
CTL
FB
PWM
Signal
GND
C3
1µF
Figure7. Using a filtered PWM Signal to CTL pin.
3. Using a DC Voltage to FB pin.
The dimming control using a DC control voltage to FB pin of the
KAB3403T/DN is shown in Figure. The LED current can be
varied applying a DC voltage to the FB pin. The voltage can come
from a filtered PWM signal. It can be used to replace the variable
DC voltage source in dimming control.
L1
4.7µH ~ 22µH
D1
V
IN
LED1
LED2
LED3
LED4
V
SW
OVD
CC
C2
1µF
KAB3403T/DN
CTL
FB
GND
R1
C1
1µF
R2
2007. 2. 26
Revision No : 0
5/7
KAB3403T/DN
V
vs V
CTL
V
vs Duty
FB
FB
350
300
250
200
150
100
50
350
300
250
200
150
100
50
VCC = 3.6V
0
0
0
10 20 30 40 50 60 70 80 90 100 110
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
VCTL (V)
Duty (%)
V
vs V
Switching Frequency vs V
FB
IN
IN
1.5
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
350
300
250
200
150
100
2.5
3.0
3.5
4.0
4.5
5.5
5.0
2.0
2.5
3.0
3.5
4.0
4.5
5.5
5.0
VIN (V)
VIN (V)
Inrush Current
Efficicncy vs Temperature
95
VIN=3.6V ILED=20µA
EN
5V/Div
VOUT
V
IN=4.3V
90
85
80
75
70
65
60
55
50
VIN=3.6V
VIN=3.0V
2V/Div
IIN
100mA/Div
Time (40µs/Div)
-60
-10
40
90
140
Temperature ( C)
2007. 2. 26
Revision No : 0
6/7
KAB3403T/DN
Switching Frequency vs Temperature
Quiescent Current vs Temperature
500
400
300
200
100
0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
-50
-10
30
70
110
-50
0
50
100
Temperature ( C)
Temperature ( C)
APPLICATION CIRCUIT
DC-DC Converter
EFFICIENCY
L1
D1
KDR730E
V
IN
10µH
16V/20mA
V
IN
100
80
60
40
20
0
R2
740k
C
1µF
OUT
OVD
CIN
1µF
CTL
FB
FB
R3
15k
3.2V
3.6V
4.2V
0
10
20
30
40
50
LOAD CURRENT (mA)
2007. 2. 26
Revision No : 0
7/7
相关型号：
KDR720S
SCHOTTKY BARRIER TYPE DIODE(FOR HIGH SPEED SWITCHING CIRCUIT, FOR SMALL CURRENT RECTIFICATION)
KEC
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