Datasheet

BCR402W
Application hints
Datasheet 14 Revision 2.0, 2012-04-12
4 Application hints
Figure 4-1 Application Circuit: Stand alone current source
Figure 4-2 Application Circuit: Supply voltages > 18 V
Application hints
BCR402W serves as an easy to use constant current source for LEDs. In stand alone application an external
resistor
R
ext
can be connected to adjust the current between 20 mA and 60 mA. R
ext
can be determined by using
Figure 3-6. Connecting a low tolerance resistor
R
ext
will improve the overall accuracy of the current sense
resistance formed by the parallel connection of
R
int
and R
ext
leading to an improved current accuracy. 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 www.infineon.com/lowcostleddriver for detailed application notes.
GND I
out
+V
S
V
drop
21
I
out
I
S
R
ext
V
S
4
3
R
ext
(optional )
GND
I
out
+V
S
V
drop
21
I
S
+ I
out
I
S
R
ext
V
S
4
3
R
ext
(optional )
I
out