BCR402R LED Driver Features • LED drive current of 20mA 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 BCR402R 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 BCR402R 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 BCR402R 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 BCR402R Pin Configuration Typical Application +Vs 4 BCR 402R 3 3 Rext Vdrop 4 1 2 1 EHA07188 Type BCR402R Marking W6s 1 = GND 2 Is Iout Pin Configuration 2 = Iout 3 = VS Package 4 = R ext 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 BCR402R 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 33 38 47 Ω Iout 18 20 22 mA Vdrop - 0.76 - 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 BCR402R 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 BCR402R 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 A A IS Iout Rext = 68 Ohm Rext = open 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 BCR402R Standard Application Circuit: Application Circuit: supply voltages >18V +Vs Vsupply BCR 402R 3 Rext Vdrop IOUT + IDRIVER LEDs 4 Rsense (optional) BCR401R BCR402R Vs 1 Rext 2 Is Iout GND IDRIVER Iout IOUT 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 Package SOT143R BCR402R 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 BCR402R 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