LED Driver BCR420U / BCR421U Datasheet Revision 2.0, 2012-05-04 Power Management & Multimarket Edition 2012-05-04 Published by Infineon Technologies AG 81726 Munich, Germany (c) 2012 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 (www.infineon.com). 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. BCR420U / BCR421U Revision History Page or Item Subjects (major changes since previous revision) Revision 2.0, 2012-05-04 All Datasheet layout updated Table 2-1 Vout limit increased Table 2-3 Rint limits tightened Table 2-3 Iout limits tightened Figure 3-13 Figure updated Figure 3-22 8 label updated Trademarks of Infineon Technologies AG AURIXTM, C166TM, CanPAKTM, CIPOSTM, CIPURSETM, EconoPACKTM, CoolMOSTM, CoolSETTM, CORECONTROLTM, CROSSAVETM, DAVETM, DI-POLTM, EasyPIMTM, EconoBRIDGETM, EconoDUALTM, EconoPIMTM, EconoPACKTM, EiceDRIVERTM, eupecTM, FCOSTM, HITFETTM, HybridPACKTM, IRFTM, ISOFACETM, IsoPACKTM, MIPAQTM, ModSTACKTM, my-dTM, NovalithICTM, OptiMOSTM, ORIGATM, POWERCODETM; PRIMARIONTM, PrimePACKTM, PrimeSTACKTM, PRO-SILTM, PROFETTM, RASICTM, ReverSaveTM, SatRICTM, SIEGETTM, SINDRIONTM, SIPMOSTM, SmartLEWISTM, SOLID FLASHTM, TEMPFETTM, thinQ!TM, TRENCHSTOPTM, TriCoreTM. 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Last Trademarks Update 2011-11-11 Datasheet 3 Revision 2.0, 2012-05-04 BCR420U / BCR421U Table of Contents Table of Contents Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1 1.1 1.2 1.3 LED Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7 7 7 2 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3 Typical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 4 Application hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 5 Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Datasheet 4 Revision 2.0, 2012-05-04 BCR420U / BCR421U List of Figures List of Figures Figure 1-1 Figure 3-1 Figure 3-2 Figure 3-3 Figure 3-4 Figure 3-5 Figure 3-6 Figure 3-7 Figure 3-8 Figure 3-9 Figure 3-10 Figure 3-11 Figure 3-12 Figure 3-13 Figure 3-14 Figure 3-15 Figure 3-16 Figure 3-17 Figure 3-18 Figure 3-19 Figure 3-20 Figure 3-21 Figure 3-22 Figure 3-23 Figure 4-1 Figure 4-2 Figure 5-1 Figure 5-2 Figure 5-3 Datasheet Pin configuration and typical application. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Total Power Dissipation Ptot = f(TS). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Permissible Pulse Load RthJS = f(tp) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Permissible Pulse Load Ptotmax / PtotDC= f(tp) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 BCR420U: Output Current versus Vout Iout = f(Vout), VEN = 40 V, Rext = Parameter . . . . . . . . . . . . . 13 BCR420U: Output Current versus Rext Iout = f(Rext), VEN = 40 V, Vout = Parameter . . . . . . . . . . . . . 13 BCR420U: Output Current versus Vout Iout = f(Vout), VEN = 40 V, Rext = open, TA = Parameter . . . . 14 BCR420U: Output Current versus Vout Iout = f(Vout), VEN = 40 V, Rext = 20 , TA = Parameter . . . . 14 BCR420U: Output Current versus Vout Iout = f(Vout), VEN = 40 V, Rext = 6 , TA = Parameter . . . . . 15 BCR420U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = open, TA = Parameter . . . . . 15 BCR420U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = 20 , TA = Parameter . . . . . 16 BCR420U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = 6 , TA = Parameter . . . . . . 16 BCR420U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = Parameter . . . . . . . . . . . . . . 17 BCR420U: Enable Current versus VEN IEN = f(VEN), Rext = open, Iout = 0 A, TA = Parameter . . . . . 17 BCR421U: Output Current versus Vout Iout = f(Vout), VEN = 3.3 V, Rext = Parameter . . . . . . . . . . . . 18 BCR421U: Output Current versus Rext Iout = f(Rext), VEN = 3.3 V, Vout = Parameter . . . . . . . . . . . . 18 BCR421U: Output Current versus Vout Iout = f(Vout), VEN = 3.3 V, Rext = open, TA = Parameter . . . 19 BCR421U: Output Current versus Vout Iout = f(Vout), VEN = 3.3 V, Rext = 20 , TA = Parameter. . . . 19 BCR421U: Output Current versus Vout Iout = f(Vout), VEN = 3.3 V, Rext = 6 , TA = Parameter. . . . . 20 BCR421U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = open, TA = Parameter . . . . . 20 BCR421U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = 20 , TA = Parameter . . . . . 21 BCR421U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = 6 , TA = Parameter . . . . . . 21 BCR421U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = Parameter . . . . . . . . . . . . . . 22 BCR421U: Enable Current versus VEN IEN = f(VEN), Rext = open, Iout = 0 A, TA = Parameter . . . . . 22 Application Circuit: Enabling / PWM by Micro Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Application Circuit: Enabling by Connecting to VS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Package Outline for SC74 (dimensions in mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Package Footprint for SC74 (dimensions in mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Tape and Reel Information for SC74 (dimensions in mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 5 Revision 2.0, 2012-05-04 BCR420U / BCR421U List of Tables List of Tables Table 2-1 Table 2-2 Table 2-3 Table 2-4 Datasheet Maximum Ratings at TA = 25 C, unless otherwise specified . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Thermal Resistance at TA = 25 C, unless otherwise specified. . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Electrical Characteristics at TA = 25 C, unless otherwise specified . . . . . . . . . . . . . . . . . . . . . . . . 9 DC Characteristics with stabilized LED load at TA = 25 C, unless otherwise specified . . . . . . . . 10 6 Revision 2.0, 2012-05-04 BCR420U / BCR421U LED Driver 1 LED Driver 1.1 Features * * * * * * * * * * LED drive current preset to 10 mA Continuous output current up to 150 mA with an external resistor Easy paralleling of drivers to increase current Supply voltage up to 40 V Low side current control Digital PWM input up to 10 kHz frequency (BCR421U) Up to 1 W power dissipation in a small SC74 package Negative thermal coefficient of -0.2 %/K reduces output current at higher temperatures RoHS compliant (Pb-free) package Automotive qualified according AEC Q101 1.2 * * * * SC74-3D Applications Architectural LED lighting Channel letters for advertising, LED strips for decorative lighting Retail lighting in fridge, freezer case and vending machines Emergency lighting (e.g. steps lighting, exit way signs etc.) 1.3 General Description The BCR420U / BCR421U provides a low-cost solution for driving 0.25 W LEDs with a typical LED current of 75 mA to 150 mA. Internal breakdown voltage is higher than 40 V which is the maximum voltage the LED driver can sustain when the output is directly connected to supply voltage. The BCR420U / BCR421U can be operated with a supply voltage of more than 40 V considering the voltage drop of the LED load which reduces the output voltage to the maximum rating of the driver. The enable pin of BCR420U can withstand a maximum voltage of 40 V which can be increased adding a series resistor in front of the enable pin reducing the voltage at the enable pin below 40 V. The digital input pin of BCR421U allows dimming via a micro controller with frequencies up to 10 kHz. A reduction of the output current at higher temperatures is the result of the negative temperature coefficient of 0.2 %/K of the LED driver. With no need for additional external components like inductors, capacitors and free wheeling diodes, the BCR420U / BCR421U LED drivers are a cost-efficient and PCB-area saving solution for driving 0.25 W LEDs. Datasheet 7 Revision 2.0, 2012-05-04 BCR420U / BCR421U LED Driver Pin Configuration Typical Application +VS EN 1 6 Rex t IEN EN OUT 2 5 OUT OUT 3 4 GND Iout 1 OUT 2,3,5 Rex t 6 GND Rex t (optional ) Vdrop 4 BCR420 U Figure 1-1 Pin configuration and typical application Type Marking BCR420U 40 1 = EN 2; 3; 5 = OUT 4 = GND 6 = Rext SC74 BCR421U 41 1 = EN 2; 3; 5 = OUT 4 = GND 6 = Rext SC74 Datasheet Pin Configuration 8 Package Revision 2.0, 2012-05-04 BCR420U / BCR421U Electrical Characteristics 2 Electrical Characteristics Table 2-1 Maximum Ratings at TA = 25 C, unless otherwise specified Parameter Symbol Values Unit Min. Typ. Max. - - 40 4.5 Enable voltage BCR420U BCR421U VEN Output current Iout - - 200 mA Output voltage Vout - - 40 V Reverse voltage between all terminals VR - - 0.5 V Total power dissipation Ptot - - 1000 mW Junction temperature TJ - - 150 C Storage temperature range TSTG -65 - 150 C Note / Test Condition V TS 100 C Attention: Stresses above the max. values listed here may cause permanent damage to the device. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Maximum ratings are absolute ratings; exceeding only one of these values may cause irreversible damage to the integrated circuit. Table 2-2 Thermal Resistance at TA = 25 C, unless otherwise specified Parameter Symbol Values Min. Typ. Unit Note / Test Condition Max. 1) Junction - soldering point RthJS 50 K/W 1) For calculation of RthJA please refer to Application Note AN077 (Thermal Resistance Calculation) Table 2-3 Electrical Characteristics at TA = 25 C, unless otherwise specified Parameter Symbol Values Min. Typ. Max. - - - 1.2 1.2 - Unit Note / Test Condition V IC = 1 mA, IB = 0 Collector-emitter breakdown voltage VBR(CEO) 40 Enable current BCR420U BCR421U IEN DC current gain hFE 200 350 500 - IC = 50 mA, VCE = 1 V Internal resistor Rint 85 95 105 IRint = 10 mA Bias resistor BCR420U BCR421U RB - 20 1.5 - Datasheet mA VEN = 24 V VEN = 3.3 V k 9 Revision 2.0, 2012-05-04 BCR420U / BCR421U Electrical Characteristics Table 2-3 Electrical Characteristics at TA = 25 C, unless otherwise specified (cont'd) Parameter Symbol Output current BCR420U BCR421U Output current at Rext = 5.1 BCR420U BCR421U Iout Voltage drop (VRext) Vdrop Table 2-4 Min. Typ. Max. 9 9 10 10 11 11 - 150 150 - 0.85 0.95 1.05 Unit Note / Test Condition mA Vout = 1.4 V VEN = 24 V VEN = 3.3 V Vout > 2.0 V VEN = 24 V VEN = 3.3 V V Iout = 10 mA DC Characteristics with stabilized LED load at TA = 25 C, unless otherwise specified Parameter Symbol Lowest sufficient supply voltage overhead VSmin Output current change versusTA BCR420U BCR421U Iout/Iout Output current change versus VS BCR420U BCR421U Iout/Iout Datasheet Values Values Min. Typ. Max. - 1.4 - - -0.2 -0.2 - - 1 1 10 - Unit Note / Test Condition V Iout > 18 mA %/K Vout > 2.0 V VEN = 24 V VEN = 3.3 V %/V Vout > 2.0 V VEN = 24 V VEN = 3.3 V Revision 2.0, 2012-05-04 BCR420U / BCR421U Typical characteristics 3 Typical characteristics 1200 1000 Ptot [mW] 800 600 400 200 0 0 20 40 60 80 TS [C] 100 120 140 Figure 3-1 Total Power Dissipation Ptot = f(TS) RthJS [K/W] 100 10 D=0 D = 0.005 D = 0.01 D = 0.02 D = 0.05 D = 0.1 D = 0.2 D = 0.5 1 0.1 -6 10 10 -5 10 -4 -3 10 tp [s] 10 -2 10 -1 0 10 Figure 3-2 Permissible Pulse Load RthJS = f(tp) Datasheet 11 Revision 2.0, 2012-05-04 BCR420U / BCR421U Typical characteristics Ptotmax / PtotDC 1000 D=0 D = 0.005 D = 0.01 D = 0.02 D = 0.05 D = 0.1 D = 0.2 D = 0.5 100 10 1 10-6 10-5 10-4 10-3 tp [s] 10-2 10-1 100 Figure 3-3 Permissible Pulse Load Ptotmax / PtotDC= f(tp) Datasheet 12 Revision 2.0, 2012-05-04 BCR420U / BCR421U Typical characteristics 0.2 Rext = 6 Iout [A] 0.15 Rext = 8 Rext = 10 0.1 Rext = 15 Rext = 30 0.05 Rext = open 0 0 1 2 3 4 5 6 7 Vout [V] 8 9 10 11 12 Figure 3-4 BCR420U: Output Current versus Vout Iout = f(Vout), VEN = 40 V, Rext = Parameter 0.2 Iout [A] 0.15 0.1 0.05 0 Vout = 1.4 V Vout = 5.4 V 1 10 Rext [] 100 Figure 3-5 BCR420U: Output Current versus Rext Iout = f(Rext), VEN = 40 V, Vout = Parameter Datasheet 13 Revision 2.0, 2012-05-04 BCR420U / BCR421U Typical characteristics 0.015 Iout [A] 0.01 0.005 0 -40 C 25 C 85 C 0 2 4 6 Vout [V] 8 10 12 Figure 3-6 BCR420U: Output Current versus Vout Iout = f(Vout), VEN = 40 V, Rext = open, TA = Parameter 0.06 0.05 Iout [A] 0.04 0.03 0.02 0.01 0 -40 C 25 C 85 C 0 2 4 6 Vout [V] 8 10 12 Figure 3-7 BCR420U: Output Current versus Vout Iout = f(Vout), VEN = 40 V, Rext = 20 , TA = Parameter Datasheet 14 Revision 2.0, 2012-05-04 BCR420U / BCR421U Typical characteristics 0.2 Iout [A] 0.15 0.1 0.05 0 -40 C 25 C 85 C 0 2 4 6 Vout [V] 8 10 12 Figure 3-8 BCR420U: Output Current versus Vout Iout = f(Vout), VEN = 40 V, Rext = 6 , TA = Parameter 0.015 Iout [A] 0.01 0.005 0 -40 C 25 C 85 C 0 5 10 15 VEN [V] 20 25 30 Figure 3-9 BCR420U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = open, TA = Parameter Datasheet 15 Revision 2.0, 2012-05-04 BCR420U / BCR421U Typical characteristics 0.06 0.05 Iout [A] 0.04 0.03 0.02 0.01 0 -40 C 25 C 85 C 0 5 10 15 VEN [V] 20 25 30 Figure 3-10 BCR420U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = 20 , TA = Parameter 0.2 Iout [A] 0.15 0.1 0.05 0 -40 C 25 C 85 C 0 5 10 15 VEN [V] 20 25 30 Figure 3-11 BCR420U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = 6 , TA = Parameter Datasheet 16 Revision 2.0, 2012-05-04 BCR420U / BCR421U Typical characteristics 0.15 Rext = open Rext = 60 Rext = 30 Rext = 10 Rext = 8 Rext = 6 Iout [A] 0.1 0.05 0 0 5 10 15 VEN [V] 20 25 30 Figure 3-12 BCR420U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = Parameter 3 2.5 IEN [mA] 2 1.5 1 0.5 0 -40 C 25 C 80 C 0 5 10 15 20 VEN [V] 25 30 35 40 Figure 3-13 BCR420U: Enable Current versus VEN IEN = f(VEN), Rext = open, Iout = 0 A, TA = Parameter Datasheet 17 Revision 2.0, 2012-05-04 BCR420U / BCR421U Typical characteristics 0.2 Iout [A] 0.15 Rext = 6 Rext = 8 Rext = 10 0.1 Rext = 15 Rext = 30 0.05 Rext = open 0 0 1 2 3 4 5 6 7 Vout [V] 8 9 10 11 12 Figure 3-14 BCR421U: Output Current versus Vout Iout = f(Vout), VEN = 3.3 V, Rext = Parameter 0.2 Iout [A] 0.15 0.1 0.05 0 Vout = 1.4 V Vout = 5.4 V 1 10 Rext [] 100 Figure 3-15 BCR421U: Output Current versus Rext Iout = f(Rext), VEN = 3.3 V, Vout = Parameter Datasheet 18 Revision 2.0, 2012-05-04 BCR420U / BCR421U Typical characteristics 0.015 Iout [A] 0.01 0.005 0 -40 C 25 C 85 C 0 2 4 6 Vout [V] 8 10 12 Figure 3-16 BCR421U: Output Current versus Vout Iout = f(Vout), VEN = 3.3 V, Rext = open, TA = Parameter 0.06 0.05 Iout [A] 0.04 0.03 0.02 0.01 0 -40 C 25 C 85 C 0 2 4 6 Vout [V] 8 10 12 Figure 3-17 BCR421U: Output Current versus Vout Iout = f(Vout), VEN = 3.3 V, Rext = 20 , TA = Parameter Datasheet 19 Revision 2.0, 2012-05-04 BCR420U / BCR421U Typical characteristics 0.2 Iout [A] 0.15 0.1 0.05 0 -40 C 25 C 85 C 0 2 4 6 Vout [V] 8 10 12 Figure 3-18 BCR421U: Output Current versus Vout Iout = f(Vout), VEN = 3.3 V, Rext = 6 , TA = Parameter 0.015 Iout [A] 0.01 0.005 0 -40 C 25 C 85 C 0 0.5 1 1.5 2 2.5 3 VEN [V] 3.5 4 4.5 5 Figure 3-19 BCR421U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = open, TA = Parameter Datasheet 20 Revision 2.0, 2012-05-04 BCR420U / BCR421U Typical characteristics 0.06 0.05 Iout [A] 0.04 0.03 0.02 0.01 0 -40 C 25 C 85 C 0 0.5 1 1.5 2 2.5 VEN [V] 3 3.5 4 4.5 5 Figure 3-20 BCR421U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = 20 , TA = Parameter 0.2 Iout [A] 0.15 0.1 0.05 0 -40 C 25 C 85 C 0 0.5 1 1.5 2 2.5 VEN [V] 3 3.5 4 4.5 5 Figure 3-21 BCR421U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = 6 , TA = Parameter Datasheet 21 Revision 2.0, 2012-05-04 BCR420U / BCR421U Typical characteristics 0.15 Rext = open Rext = 60 Rext = 30 Rext = 10 Rext = 8 Rext = 6 Iout [A] 0.1 0.05 0 0 0.5 1 1.5 2 2.5 VEN [V] 3 3.5 4 4.5 5 Figure 3-22 BCR421U: Output Current versus VEN Iout = f(VEN), Vout = 2 V, Rext = Parameter 3 2.5 IEN [mA] 2 1.5 1 0.5 0 -40 C 25 C 80 C 0 0.5 1 1.5 2 2.5 VEN [V] 3 3.5 4 4.5 5 Figure 3-23 BCR421U: Enable Current versus VEN IEN = f(VEN), Rext = open, Iout = 0 A, TA = Parameter Datasheet 22 Revision 2.0, 2012-05-04 BCR420U / BCR421U Application hints 4 Application hints +V S C IEN EN Iout 1 OUT 2,3,5 Rex t 6 GND Rex t (optional ) Vdrop 4 BCR421 U Figure 4-1 Application Circuit: Enabling / PWM by Micro Controller +V S EN IEN Iout 1 OUT 2,3,5 Rex t 6 GND Rex t (optional ) V drop 4 BCR420U Figure 4-2 Application Circuit: Enabling by Connecting to VS Application hints BCR420U / BCR421U serve as an easy to use constant current sources for LEDs. In stand alone application an external resistor can be connected to adjust the current from 10 mA to 250 mA. Rext can be determined by using Figure 3-5 or Figure 3-15. Connecting a low tolerance resistor Rext will improve the overall accuracy of the current sense resistance formed by the parallel connection of Rint and Rext 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 application notes and for up-to-date application information. Datasheet 23 Revision 2.0, 2012-05-04 BCR420U / BCR421U Package Package 2.9 0.2 (2.25) B 1.1 MAX. 0.15 +0.1 -0.06 5 4 1 2 3 0.35 +0.1 -0.05 Pin 1 marking 0.2 1.6 0.1 6 2.5 0.1 (0.35) 0.25 0.1 5 A B 6x M 0.1 MAX. 0.95 0.2 1.9 M A SC74-PO V04 Figure 5-1 Package Outline for SC74 (dimensions in mm) 2.9 1.9 0.5 0.95 SC74-FPR V04 Figure 5-2 Package Footprint for SC74 (dimensions in mm) 0.2 2.7 8 4 Pin 1 marking 3.15 1.15 SC74-TP Figure 5-3 Tape and Reel Information for SC74 (dimensions in mm) Datasheet 24 Revision 2.0, 2012-05-04 BCR420U / BCR421U Terminology Terminology Iout/Iout Output current change hFE DC current gain IEN Enable current Iout Output current IR Reverse current LED Light Emitting Diode PCB Printed Circuit Board Ptot Total power dissipation PWM Pulse Width Modulation RB Bias resistor Rext External resistor Rint Internal resistor RoHs Restriction of Hazardous Substance directive RthJS Thermal resistance junction to soldering point TA Ambient temperature TJ Junction temperature TS Soldering point temperature Tstg Storage temperature VBR(CEO) Collector-emitter breakdown voltage VBR Breakdown voltage Vdrop Voltage drop VEN Enable voltage Vout Output voltage VR Reverse voltage VS Supply voltage VSmin Lowest sufficient supply voltage overhead Datasheet 25 Revision 2.0, 2012-05-04 w w w . i n f i n e o n . c o m Published by Infineon Technologies AG