INFINEON BCR401R

BCR401R
LED Driver
Features
• LED drive current of 10mA
3
• Output current adjustable up to 60mA with
external resistor
2
4
1
• Supply voltage up to 18V
• Easy paralleling of drivers to increase current
• Low voltage overhead of 1.2V
• High current accuracy at supply voltage variation
• No EMI
• Reduced output current at higher temperatures - negative thermal coefficient of -0.3% / K
• RoHS compliant (pb-free) SOT143R package
• Qualified according AEC Q101
Applications
• Channel letters for advertising, LED strips for decorative lighting
• Aircraft, train, ship illumination
• Retrofits for general lighting, white goods like refrigerator lighting
• Medical lighting
General Description
The BCR401R is a cost efficient LED driver to drive low power LED’s. The advantages
towards resistor biasing are:
• homogenous light output despite varying forward voltages in different LED strings
• homogenous light output of LED’s despite voltage drop across long supply lines
• homogenous light output independent from supply voltage variations
• longer lifetime of the LED’s due to reduced output current at higher temperatures
(negative thermal coefficient)
The advantages towards discrete solutions are:
• lower assembly cost
• smaller form factor
• better quality due to less soldering points
• higher output current accuracy due to pretested LED drivers
Dimming is possible by using an external digital transistor at the ground pin.
The BCR401R can be operated at higher supply voltages by putting LED’s between the
power supply +VS and the power supply pin of the LED driver. You can find further details
in the application note AN066.
The BCR401R is a perfect fit for numerous low power LED applications by combining small
form factor with low cost. These LED drivers offer several advantages to resistors like
significantly higher current control at very low voltage drop ensuring high lifetime of LED’s.
1
2009-11-13
BCR401R
Pin Configuration
Typical Application
+ V s
4
B C R
3
4 0 1 R
3
R e x t
V d ro p
4
1
2
1
EHA07188
Type
Marking
BCR401R
W5s
2
Is
Io u t
Pin Configuration
1 = GND
2 = Iout
3 = VS
Package
4 = Rext
SOT143R
Maximum Ratings
Parameter
Symbol
Supply voltage
VS
18
V
Output current
Iout
60
mA
Output voltage
Vout
16
V
Reverse voltage between all terminals
VR
0.5
Total power dissipation, TS = 75 °C
Ptot
330
mW
Junction temperature
Tj
150
°C
Storage temperature
Tstg
Value
Unit
-65 ... 150
Thermal Resistance
Parameter
Symbol
Junction - soldering point1)
RthJS
Value
Unit
225
K/W
1For calculation of R
thJA please refer to Application Note Thermal Resistance
2
2009-11-13
BCR401R
Electrical Characteristics at TA=25°C, unless otherwise specified
Symbol
Parameter
Values
Unit
min.
typ.
max.
VBR(CEO)
18
-
-
IS
350
440
540
hFE
-
150
-
-
Rint
66
79
94
Ω
Iout
9
10
11
mA
Vdrop
-
0.79
-
V
VSmin
-
1.2
-
V
∆Iout/Iout
-
-0.3
-
%/K
∆Iout/Iout
-
2
-
%/V
Characteristics
Collector-emitter breakdown voltage
-
IC = 100 µA, IB = 0
Supply current
µA
VS = 10 V
DC current gain
IC = 50 mA, VCE = 1 V
Internal resistor
IRint = 10 mA
Output current
VS = 10 V, Vout = 7.6 V
Voltage drop (VS - VE)
Iout = 20 mA
DC Characteristics with stabilized LED load
Lowest sufficient supply voltage overhead
Iout > 8mA
Output current change versus T A
VS = 10 V
Output current change versus VS
VS = 10 V
3
2009-11-13
BCR401R
Total power dissipation Ptot = f (TS)
Permissible Pulse Load RthJS = f (tp)
10 3
360
mA
K/W
300
RthJS
P tot
270
240
10 2
210
180
150
10
120
0.5
0.2
0.1
0.05
0.02
0.01
0.005
D=0
1
90
60
30
0
0
15
30
45
60
75
90 105 120 °C
10 0 -7
10
150
TS
10
-6
10
-5
10
-4
10
-3
10
-2
s
10
0
tp
Permissible Pulse Load
Ptotmax / PtotDC = f (tp)
P totmax/ P totDC
10 2
D=0
0.005
0.01
0.02
0.05
0.1
0.2
0.5
-
10 1
10 0 -7
10
10
-6
10
-5
10
-4
10
-3
10
-2
s
10
0
tp
4
2009-11-13
BCR401R
Output current versus supply voltage
Supply current versus supply voltage
Iout = f (V S); R ext = Parameter
IS = f(VS)
Load: two LEDs with VF = 3.8V in series
Load: two LEDs with VF = 3.8V in series
10
-1
10 -3
Rext = 36 Ohm
Rext = 82 Ohm
Rext = 160 Ohm
Rext = open
A
IS
Iout
A
10 -2
10 -3
0
10 -4
2
4
6
8
10
12
14
16
V
10 -5
0
20
VS
2
4
6
8
10
12
14
16
V
20
VS
Output current versus reference voltage
Iout = f (V DROP); VS = 10V; V out = 7.6V
10 -1
A
Iout
10 -2
10 -3
10 -4
10 -5
0.6
0.65
0.7
0.75
0.8
0.85
0.9
V
1
Vdrop
5
2009-11-13
BCR401R
Standard Application Circuit:
Application Circuit:
supply voltages >18V
+ V s
B C R
4 0 1 R
Vsupply
3
R e x t
V d ro p
IOUT + IDRIVER
LEDs
4
Rsense
(optional)
BCR401R
BCR402R
Vs
1
Rext
2
Is
Io u t
GND
IDRIVER
Iout
IOUT
LEDs
Application hints
BCR401R serves as an easy to use constant current source for LEDs. In stand alone
application an external resistor can be connected to adjust the current from 10 mA to 60 mA.
Rext can be determined by using the diagram 'Output current versus external resistor',
or by refering to diagram 'Output current versus reference voltage'. Look for your desired
output current on the y axis and read out the corresponding Vdrop. Calculate Rext:
Rext = Vdrop / (Iout -(Vdrop/Rint))
Please take into account that the resulting output currents will be slightly lower due to the
self heating of the component and the negative thermal coefficient.
Please visit our web site for application notes: www.infineon.com/lowcostleddriver
• AN066 explains the basic concept
• AN077 gives hints to thermal design
• AN159 provides information how to add a power transistor to increase the output current
6
2009-11-13
Package SOT143R
BCR401R
Package Outline
1
2
0.2
0.08...0.15
A
+0.1
0.8 -0.05
0.4 +0.1
-0.05
0˚... 8˚
1.7
0.25
0.1 MAX.
10˚ MAX.
1.3 ±0.1
3
2.4 ±0.15
4
1 ±0.1
0.15 MIN.
B
1.9
10˚ MAX.
2.9 ±0.1
M
0.2
M
A
B
Foot Print
1.2
0.8
0.9
1.1
0.9
0.8
0.8
0.8
1.2
Marking Layout (Example)
Reverse bar
2005, June
Date code (YM)
Pin 1
Manufacturer
BFP181R
Type code
Standard Packing
Reel ø180 mm = 3.000 Pieces/Reel
Reel ø330 mm = 10.000 Pieces/Reel
0.2
2.6
8
4
Pin 1
3.15
1.15
7
2009-11-13
BCR401R
Published by
Infineon Technologies AG
81726 München, Germany
© Infineon Technologies AG 2007.
All Rights Reserved.
Attention please!
The information given in this data sheet shall in no event be regarded as a guarantee
of conditions or characteristics (“Beschaffenheitsgarantie”). With respect to any
examples or hints given herein, any typical values stated herein and/or any information
regarding the application of the device, Infineon Technologies hereby disclaims any
and all warranties and liabilities of any kind, including without limitation warranties of
non-infringement of intellectual property rights of any third party.
Information
For further information on technology, delivery terms and conditions and prices
please contact your nearest Infineon Technologies Office (www.infineon.com).
Warnings
Due to technical requirements components may contain dangerous substances.
For information on the types in question please contact your nearest
Infineon Technologies Office.
Infineon Technologies Components may only be used in life-support devices or
systems with the express written approval of Infineon Technologies, if a failure of
such components can reasonably be expected to cause the failure of that
life-support device or system, or to affect the safety or effectiveness of that
device or system.
Life support devices or systems are intended to be implanted in the human body,
or to support and/or maintain and sustain and/or protect human life. If they fail,
it is reasonable to assume that the health of the user or other persons
may be endangered.
8
2009-11-13