LR246 [LRC]
OverVoltage Function Fast 1.2MHz Switching Frequency High Efficiency: 85% Typical; 过电压功能快速1.2MHz开关频率高效率： 85 ％（典型）
| 型号： | LR246 |
| 厂家： | 
LESHAN RADIO COMPANY |
| 描述： | OverVoltage Function Fast 1.2MHz Switching Frequency High Efficiency: 85% Typical |
| 文件： | 总8页 (文件大小：216K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
LESHAN RADIO COMPANY, LTD.
LR246 White LED Step-Up Converter
¾
¾
¾
¾
¾
¾
¾
¾
¾
OverVoltage Function
LR246 is a step-up DC/DC converter
specifically designed to drive white LED with a
constant current. It can drive two,three,or four
LEDS. It switches at 1.2MHz and use tiny
external components. The output capacitor can
be as small as 0.22uF,which can save space
and cost versus alternative solutions. Feedback
voltage is as low as 95mV. Built-in OverVoltage
function.
Fast 1.2MHz Switching Frequency
Requires Only 0.22uF Output Capacitor
Inherently Matched LED Current
High Efficiency: 85% Typical
2.5V to 10V VIN ranges
Drives Up to Four series LEDs with a Li-lon cell
Uses Very Tiny Inductors
SOT-26 Package
Absolute maximum ratings
Parameter
Supply Voltage
symbol
VIN
value
unit
V
10
10
Feedback Voltage
Switch Voltage
FB
V
SW
VCE
Topr
Rstg
Tj
20
V
CE Voltage
10
V
Operating temperature range
Storage temperature range
Junction temperature
-25 to +70
-55 to +150
125
℃
℃
℃
Pin name
Description
Symbol
Description
6：Supply
Voltage
Symbol
VIN
1
2
3
6
5
4
1：Switch
SW
5：Over
Voltage
2：GND
GND
FB
OVP
CE
3：Feedback
4：Start-Up
1/8
LESHAN RADIO COMPANY, LTD.
LR246
Block Diagram
PIN1(SW)
PWM
CONTROL
PIN5(OVP)
CURRENT SENSE
+
SLOPE COMP
Fosc
+
0
0
-
PIN6(VIN)
VREF
0
PIN2(GND)
PIN3(FB)
+
gm
-
-
SHUTDOWN
+
D246
2/8
LESHAN RADIO COMPANY, LTD.
LR246
Electrical Characteristics
Tamb = 25℃, VIN=3V，VCE=3V,unless otherwise specified.
Parameter
Test Conditions / Pins
Min
2.5
Type
Max
Unit
V
Minimum Operating Voltage
Maximum Operating Voltage
10
V
ISW=100mA,
Feedback Voltage
FB Pin Bias Current
Supply Current
86
50
95
104
200
mV
nA
Duty Cycle=66%
100
1.9
0.1
2.5
1
mA
uA
VCE=0V
Switching Frequency
0.8
85
1.2
1.6
MHz
Maximum Duty Cycle
OVP Protection
90
27
%
V
Switch Current Limit
Switch VCESAT
320
350
0.01
mA
mV
uA
V
ISW =250mA
VSW=5V
Switch Leakage Current
CE Voltage High
5
1.5
CE Voltage Low
0.4
V
CE Pin Bias Current
65
uA
Typical Application
L1
1
2
HI
22uH
VCC
D4
1
PIN1(SW)
2
PWM
CONTROL
D1
D1
D1
PIN5(OVP)
C1
1u
CURRENT SENSE
C2
0.22u
+
SLOPECOMP
Fosc
+
0
0
-
PIN6(VIN)
0
VREF
PIN2(GND)
PIN3(FB)
+
gm
-
1k
-
SHUTDOWN
R1
+
3/8
LESHAN RADIO COMPANY, LTD.
LR246
Analog Voltage Light Control
L1
1
2
HI
22uH
VCC
D4
1
PIN1(SW)
2
PWM
D1
CONTROL
PIN5(OVP)
C1
1u
CURRENT SENSE
C2
0.22u
+
SLOPE COMP
Fosc
+
D1
0
0
-
PIN6(VIN)
0
VREF
PIN2(GND)
PIN3(FB)
D1
+
gm
-
5K
-
R1
SHUTDOWN
+
90K
HI
VDC
Logic Voltage Light Control
L1
22uH
1
2
HI
VCC
D4
1
PIN1(SW)
2
PWM
CONTROL
D1
D1
D1
PIN5(OVP)
C1
1u
CURRENT SENSE
C2
0.22u
+
SLOPE COMP
Fosc
+
0
0
-
PIN6(VIN)
VREF
0
PIN2(GND)
PIN3(FB)
+
gm
-
1k
-
R1
HI
SHUTDOWN
+
PWM
4/8
LESHAN RADIO COMPANY, LTD.
LR246
Figure
Iq Vs T
2.2
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
-50
100
25
0
2
4
6
8
10
Vin(V)
Swich Frequency Vs T
1.4
1.2
1
0.8
0.6
0.4
0.2
0
-25
0
25
50
75
100
T（°C）
5/8
LESHAN RADIO COMPANY, LTD.
LR246
η VS T
84.5
84
83.5
83
82.5
82
81.5
81
ILED=10mA
ILED=15mA
ILED=20mA
80.5
80
-25
0
25
50
75
100
T（°C）
Drive 2LED
86
84
82
80
78
76
74
72
70
0
Vin=3.6V
Vin=3V
10
20
ILED(mA)
30
40
6/8
LESHAN RADIO COMPANY, LTD.
LR246
Drive 3LED
90
85
80
75
70
65
60
Vin=3V
Vin=3.6V
0
5
10
ILED（mA）
15
20
7/8
LESHAN RADIO COMPANY, LTD.
LR246
SOT-26 Diagram
Dimension(in mm)
max
Dimension(in Inch)
Symbol
min
min
max
A
A1
B
0.787
1.450
0.152
1.803
0.559
2.997
3.099
1.041
0.254
0.031
0.057
0.006
0.071
0.022
0.118
0.122
0.041
0.010
0.024
1.397
0.250
2.591
2.692
0.838
0.080
0.300
0.055
0.010
0.102
0.106
0.033
0.003
0.012
b
C
D
E
H
L
0.610
8/8
相关型号：
©2020 ICPDF网 联系我们和版权申明