BCR402R_09 Datasheet, PDF (6/8 Pages) Infineon Technologies AG – LED Driver

BCR402R
Standard Application Circuit:
Application Circuit:
supply voltages >18V
BCR 402R
+Vs
3
Vsupply
Rext Vdrop
4
I_OUT + I_DRIVER
LEDs
BCR401R
BCR402R
Vs
Rext
Rsense
(optional)
1
2
Is
Iout
GND Iout
I_DRIVER
I_OUT
LEDs
Application hints
BCR402R 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 20 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
6
2009-11-13