BCR402U LED Driver Features LED drive current of 20mA Output current adjustable up to 65mA with external resistor 4 3 5 Supply voltage up to 40V 2 6 1 Easy paralleling of drivers to increase current Low voltage overhead of 1.4V High current accuracy at supply voltage variation No EMI High power dissipation of 750mW Reduced output current at higher temperatures - Negative thermal coefficient of -0.2% / K RoHS compliant (pb-free) small and robust SC-74 package Qualified according to 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 Automotive applications like CHMSL and rear combination lights General Description The BCR402U is a cost efficient LED driver to drive low power LEDs. The advantages towards resistor biasing are: homogenous light output despite varying forward voltages in different LED strings homogenous light output of LEDs despite voltage drop across long supply lines homogenous light output independent from supply voltage variations longer lifetime of the LEDs 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 BCR402U can be operated at higher supply voltages by putting LEDs between the power supply +VS and the power supply pin of the LED driver. You can find further details in the application note AN097. The BCR402U 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 LEDs. 2009-07-31 1BCR402U Pin Configuration Typical Application +Vs BCR402U BCR 402U 4 GND 1 6 Rext Rext Vdrop (optional) 6 Out 2 5 Out Out 3 4 Vs 1 2,3,5 Is Iout Type Marking Pin Configuration Package BCR402U L2s 1 = GND 2 3 5 = Out 4 = V 6 = R SC74 S ext Maximum Ratings Parameter Symbol Value Unit Supply voltage V 40 V S Output current I 65 mA out 38 V Output voltage V out Reverse voltage between all terminals V 0.5 R P 750 mW Total power dissipation, T = 125 C tot S Junction temperature T 150 C j Storage temperature T -65 ... 150 stg Thermal Resistance Parameter Symbol Value Unit 1) R K/W Junction - soldering point 50 thJS 1 For calculation of R please refer to Application Note Thermal Resistance thJA 2009-07-31 2