BCR402W

BCR402W LED Driver Features • LED drive current of 20mA • Output current adjustable up to 60mA with external resistor • 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) small SOT343 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 BCR402W 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 BCR402W 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 AN182. The BCR402W 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. 3 4 1 2 1 2010-01-12 BCR402W Pin Configuration 4 3 Typical Application +Vs B C R 402W 3 R e x t V d ro p 4 1 2 1 2 EHA07188 Type BCR402W Maximum Ratings Parameter Supply voltage Output current Output voltage Marking W6s 1 = GND Pin Configuration 2 = Iout 3 = VS 4 = R ext Package SOT343 Symbol Value 18 60 16 0.5 500 150 -65 ... 150 Unit V mA V mW °C VS Iout Vout VR Ptot Tj Tstg Reverse voltage between all terminals Total power dissipation, TS ≤ 95 °C Junction temperature Storage temperature Thermal Resistance Parameter Junction - soldering point1) Symbol Value 110 Unit K/W RthJS 1For calculation of R thJA please refer to Application Note Thermal Resistance 2 2010-01-12 BCR402W Electrical Characteristics at TA=25°C, unless otherwise specified Parameter Characteristics Collector-emitter breakdown voltage Symbol min. Values typ. 440 150 38 20 0.76 max. 540 47 22 µA Ω mA V Unit VBR(CEO) IS hFE Rint Iout Vdrop 18 350 33 18 - IC = 100 µA, IB = 0 Supply current VS = 1 0 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 VSmin ∆Iout/Iout ∆Iout/Iout - 1.2 -0.3 2 - V %/K %/V Iout > 8mA Output current change versus T A VS = 10 V Output current change versus VS VS = 10 V 3 2010-01-12 BCR402W Total power dissipation Ptot = f (TS) Permissible Pulse Load RthJS = f (tp) 550 mW 10 3 450 400 RthJS P tot 10 2 350 300 250 200 150 100 50 0 0 15 30 45 60 75 90 105 120 °C 150 10 1 D = 0,5 0,2 0,1 0,05 0,02 0,01 0,005 0 10 0 - 6 10 10 -5 10 -4 10 -3 10 -2 s 10 0 TS tp Permissible Pulse Load Ptotmax / PtotDC = f (tp) 10 2 P totmax/P totDC - 10 1 D=0 0.005 0.01 0.02 0.05 0.1 0.2 0.5 10 0 - 6 10 10 -5 10 -4 10 -3 10 -2 s 10 0 tp 4 2010-01-12 BCR402W Output current versus supply voltage Supply current versus supply voltage Iout = f (V S); R ext = Parameter Load: two LEDs with VF = 3.8V in series 10 -1 IS = f(VS) Load: two LEDs with VF = 3.8V in series 10 - 3 A Rext = 68 Ohm A Iout Rext = open 10 - 2 IS 10 - 4 V 10 -3 0 2 4 6 8 10 12 14 16 20 10 -5 0 2 4 6 8 10 12 14 16 V 20 VS VS Output current versus external resistor Output current versus reference voltage Iout = f (Rext ); VS = 10V; V out = 7.6V 0.06 Iout = f (V DROP); VS = 10V; V out = 7.6V 10 - 1 A A 10 - 2 Iout Iout 10 - 3 10 - 4 2 0.04 0.03 0.02 0.01 01 10 10 OHM 10 3 10 -5 0.6 0.65 0.7 0.75 0.8 0.85 0.9 V 1 Rext. Vdrop 5 2010-01-12 BCR402W Standard Application Circuit: Application Circuit: supply voltages >18V +Vs B C R 402W 3 Vsupply R ext Vdrop 4 IOUT + IDRIVER LEDs BCR401W BCR402W Vs Rext Rsense (optional) 1 2 GND IDRIVER Iout IOUT LEDs Application hints BCR402W 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 • AN077 gives hints to thermal design • AN182 provides a guideline for replacing resistor biasing with BCR401W / BCR402W constant current sources in 12 & 24V striplight applications 6 2010-01-12 Package SOT343 BCR402W Package Outline 2 ±0.2 1.3 4 3 0.15 1 0.3 +0.1 -0.05 4x 0.1 M 0.9 ±0.1 0.1 MAX. 0.1 A 1.25 ±0.1 2.1 ±0.1 2 0.6 +0.1 -0.05 0.1 MIN. 0.15 -0.05 0.2 M +0.1 A Foot Print 0.6 0.8 1.15 0.9 Marking Layout (Example) Manufacturer 1.6 2005, June Date code (YM) Pin 1 BGA420 Type code Standard Packing Reel ø180 mm = 3.000 Pieces/Reel Reel ø330 mm = 10.000 Pieces/Reel 4 0.2 Pin 1 2.15 2.3 8 1.1 7 2010-01-12 BCR402W Edition 2009-11-16 Published by Infineon Technologies AG 81726 Munich, Germany  2009 Infineon Technologies AG All Rights Reserved. Legal Disclaimer The information given in this document shall in no event be regarded as a guarantee of conditions or characteristics. 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 the nearest Infineon Technologies Office (). Warnings Due to technical requirements, components may contain dangerous substances. For information on the types in question, please contact the nearest Infineon Technologies Office. Infineon Technologies components may be used in life-support devices or systems only 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 2010-01-12