BCR420U / BCR421U LED Driver Features • Continuous output current up to 150mA 4 3 5 with external resistor 2 6 • Suitable for supply voltages of 40V and above 1 • Low side current control, µC compatible PWM input (BCR421U) up to 10kHz • Up to 1W power dissipation in a small SC74 package • Negative thermal coefficient reduces output current at higher temperatures • Easy paralleling of drivers to increase current • Pb-free (RoHS compliant) package • Automotive qualified according AEC Q101 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.) • Ship, train and aircraft interior illumination General Description The BCR420U/BCR421U provide a low-cost solution for driving 0.25W LEDs with a typical LED current ILED of 75mA to 150mA. Internal breakdown voltage is >40V, this is the maximum voltage that the LED driver IC can sustain when connected to it directly. The BCR420U/BCR421U can be operated at supply voltages of 40V or higher, by simply stacking a series of LEDs in front of the LED drivers, resulting in a certain voltage drop depending on the forward voltages of the LEDs, reducing the voltage at the supply pin of the driver below 40V. A digital input pin (BCR421U) allows dimming via a Microcontroller with frequencies of up to 10 kHz. A reduction of the output current at higher temperatures is the result of the negative thermal coefficient of 0.2% /K. of the LED drivers. 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 0.25W LEDs. 1 2010-01-15 BCR420U / BCR421U Pin Configuration Typical Application +Vs 6 5 4 µC IEN IOUT 1 OUT 2,3,5 EN 1 2 3 Rext 6 Vdrop GND 4 BCR421U Type Marking BCR420U 40 BCR421U 41 Pin Configuration 1 = EN 2;3;5 = 4 = GND Package 6 = Rext OUT SC74 SC74 Maximum Ratings Parameter Symbol Enable voltage VEN Value Unit V BCR420U 40 BCR421U 4.5 Output current Iout 200 mA Output voltage 38 V Reverse voltage between all terminals Vout VR 0.5 Total power dissipation, TS = 100 °C Ptot 1000 Junction temperature Tj Storage temperature Tstg 150 mW °C -65 ... 150 Thermal Resistance Parameter Symbol Junction - soldering point1) RthJS Value Unit 50 K/W 1For calculation of R thJA please refer to Application Note Thermal Resistance 2 2010-01-15 BCR420U / BCR421U Electrical Characteristics at TA=25°C, unless otherwise specified Parameter Symbol Values Unit min. typ. max. 40 - - Characteristics VBR(CEO) Collector-emitter breakdown voltage V IC = 1 mA, I B = 0 IEN Enable current mA VEN = 24 V , BCR420U - 1.2 - VEN = 3.3 V , BCR421U - 1.2 - hFE 200 350 500 - Rint 65 90 105 Ω DC current gain IC = 50 mA, VCE = 1 V Internal resistor IRint = 10 mA RB Bias resistor kΩ BCR420U - 20 - BCR421U - 1.5 mA Iout Output current Vout = 1.4 V, V EN = 24 V, BCR420U 8 10 12 Vout = 1.4 V, V EN = 3.3 V, BCR421U 8 10 12 - 150 - - 150 - Vdrop 0.85 0.95 1.05 V VSmin - 1.4 - V Vout > 2.0 V, V EN = 24 V, REXT = 5.1 Ω, BCR420U Vout > 2.0 V, V EN = 3.3 V, R EXT = 5.1 Ω, BCR421U Voltage drop (VS - VE) Iout = 10mA DC Characteristics with stabilized LED load Lowest sufficient supply voltage overhead Iout > 18mA ∆Iout/Iout Output current change versus TA %/K VEN = 24 V; Vout > 2.0 V, BCR420U - -0.2 - VEN = 3.3 V; Vout > 2.0 V, BCR421U - -0.2 - ∆Iout/Iout Output current change versus VS %/V VEN = 24 V; Vout > 2.0 V, BCR420U - 1 - VEN = 3.3 V; Vout > 2.0 V, BCR421U - 1 - 3 2010-01-15 BCR420U / BCR421U Total power dissipation P tot = f (TS) Permissible Pulse Load RthJS = f (tp) 10 3 1200 mW 1000 10 2 R thJS Ptot 900 800 700 10 1 600 D = 0,5 0,2 0,1 0,05 0,02 0,01 0,005 0 500 400 10 0 300 200 100 0 0 20 40 60 80 120 °C 100 10 -1 -6 10 150 10 -5 10 -4 10 -3 10 -2 s 10 0 TP TS Permissible Pulse Load Ptotmax / PtotDC = f (tp) 10 3 Ptotmax/PtotDC - 10 2 D=0 0.005 0.01 0.02 0.05 0.1 0.2 0.5 10 1 10 0 -6 10 10 -5 10 -4 10 -3 10 -2 s 10 0 TP 4 2010-01-15 BCR420U / BCR421U BCR420U: Output current versus V out BCR420U: Output current versus Rext Iout = f (V out ); VEN = 40 V; Iout = f (R ext ); VEN = 24 V; Iout = 0; Rext = Parameter Vout = Parameter 0.2 0.2 A Rext = 8 Ohm A Vout = 5.4V Vout = 1.4V Iout Iout Rext = 6 Ohm Rext = 10 Ohm 0.1 Rext = 15 Ohm Rext = 30 Ohm 0.05 Rext = open 0 0 2 4 6 8 V 0 0 10 12 10 1 Ohm 10 Vout Rext. BCR420U: Output current versus V out BCR320U: Output current versus V out Iout = f (V S ); V EN = 40 V; Rext = open; Iout = f (V S ); V EN = 40 V; Rext = 20 Ohm; TA= Parameter TA= Parameter 2 0.08 0.015 TA = -40°C TA = 25°C TA = 85°C A Iout Iout A 0.04 TA = -40°C TA = 25°C TA = 85°C 0.005 0.02 0 0 2 4 6 8 V 0 0 12 Vout 2 4 6 8 V 12 Vout 5 2010-01-15 BCR420U / BCR421U BCR420U: Output current versus V out BCR420U: Output current versus V EN Iout = f (V S ); V EN = 40 V; Rext = 6 Ohm; Iout = f (VEN); Vout = 2.0 V; Rext = open; TA= Parameter TA = Parameter A A TA = -40°C TA = 25°C TA = 85°C Iout 0.02 Iout 0.2 0.1 0.01 TA = -40°C TA = 25°C TA = 85°C 0.05 0 0 2 4 6 8 0.005 V 0 0 12 5 10 15 20 V 30 Vout VEN BCR420U: Output current versus V EN BCR420U: Output current versus V EN Iout = f (VEN); Vout = 2.0 V; Rext = 20 Ohm; Iout = f (VEN); Vout = 2.0 V; Rext = 6 Ohm; TA = Parameter TA = Parameter 0.15 0.06 A Iout Iout A 0.04 0.03 TA = 85°C TA = 25°C TA = -40°C TA = -40°C TA = 25°C TA = 85°C 0.05 0.02 0.01 0 0 5 10 15 20 V 0 0 30 VEN 5 10 15 20 V 30 VEN 6 2010-01-15 BCR420U / BCR421U BCR420U: Output current versus V EN BCR420U: Enable current versus VEN Iout = f (VEN); Vout = 2.0 V; IEN = f (V EN ); Rext = open; Iout = 0; Rext = Parameter TA = Parameter 0.15 3 Rext = 6 Ohm Rext = 8 Ohm IEN mA Iout A Rext = 10 Ohm TA = 80°C TA = 25°C TA = -40°C 0.05 1 Rext = 30 Ohm Rext = 60 Ohm Rext = open 0 0 5 10 15 20 V 0 0 30 0.5 1 1.5 2 2.5 3 3.5 4 Ohm VEN VEN BCR421U: Output current versus V out BCR421U: Output current versus Rext Iout = f (V out); VEN = 3.3 V; Iout = f (R ext); V EN = 3.3 V; Rext = Parameter Vout = Parameter 0.2 5 0.2 A Iout Iout Rext = 6 Ohm Rext = 8 Ohm A Rext = 10 Ohm 0.1 Vout = 5.4V Vout = 1.4V Rext = 15 Ohm 0.05 Rext = 30 Ohm Rext = open 0 0 2 4 6 8 V 0 0 10 12 Vout 10 1 Ohm 10 2 Rext. 7 2010-01-15 BCR420U / BCR421U BCR421U: Output current versus V out BCR421U: Output current versus V out Iout = f (V S ); V EN = 3.3 V; Rext = open; Iout = f (V S ); V EN = 3.3 V; Rext = 20 Ohm; TA= Parameter TA= Parameter 0.015 0.06 TA = -40°C TA = 25°C TA = 85°C Iout A Iout A TA = -40°C TA = 25°C TA = 85°C 0.005 0 0 0.02 2 4 6 8 V 0 0 12 2 4 6 V 8 12 Vout Vout BCR421U: Output current versus V out BCR421U: Output current versus V EN Iout = f (V S ); V EN = 3.3 V; Rext = 6 Ohm; Iout = f (VEN); Vout = 2.0 V; Rext = open TA= Parameter TA = Parameter A A TA = -40°C TA = 25°C TA = 85°C Iout 0.02 Iout 0.2 0.1 0.01 TA = -40°C TA = 25°C TA = 85°C 0.05 0 0 2 4 6 8 0.005 V 0 0 12 Vout 1 2 3 V 5 VEN 8 2010-01-15 BCR420U / BCR421U BCR421U: Output current versus V EN BCR421U: Output current versus V EN Iout = f (VEN); Vout = 2.0 V; Rext = 20 Ohm Iout = f (VEN); Vout = 2.0 V; Rext = 6 Ohm TA = Parameter TA = Parameter 0.15 0.06 A Iout Iout A 0.04 TA = -40°C TA = 25°C TA = 85°C 0.03 TA = 85°C TA = 25°C TA = -40°C 0.05 0.02 0.01 0 0 1 2 V 3 0 0 5 1 2 V 3 5 VEN VEN BCR421U: Output current versus V EN BCR421U: Enable current versus VEN Iout = f (VEN); VS = 3.3 V; IEN = f (V EN); Rext = open; Iout = 0 Rext = Parameter TA = Parameter 0.15 3 Rext = 6 Ohm Rext = 9 Ohm A mA Iout IEN Rext = 10 Ohm TA = 80°C TA = 25°C TA = -40°C 0.05 1 Rext = 30 Ohm Rext = 60 Ohm Rext = open 0 0 1 2 3 V 0 0 5 VEN 0.5 1 1.5 2 2.5 3 3.5 4 Ohm 5 VEN 9 2010-01-15 BCR420U / BCR421U Application circuit: Enabling / PWM by micro controller Application circuit: Enabling by connecting to Vs +Vs +Vs µC IOUT IEN EN 1 OUT 2,3,5 EN IEN IOUT OUT 2,3,5 Rext Rext 6 6 Vdrop Vdrop GND GND 4 4 BCR420U BCR421U 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 150 mA. Rext can be determined by using the diagram 'Output current versus external resistor'. 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 for up-to-date application information 10 2010-01-15 Package SC74 BCR420U / BCR421U Package Outline B 1.1 MAX. 1 2 3 0.35 +0.1 -0.05 Pin 1 marking 0.2 B 6x M A 0.1 MAX. 0.95 0.2 1.9 1.6 ±0.1 4 10˚ MAX. 5 2.5 ±0.1 6 0.25 ±0.1 0.15 +0.1 -0.06 (0.35) 10˚ MAX. 2.9 ±0.2 (2.25) M A Foot Print 2.9 1.9 0.5 0.95 Marking Layout (Example) Small variations in positioning of Date code, Type code and Manufacture are possible. Manufacturer 2005, June Date code (Year/Month) Pin 1 marking Laser marking BCW66H Type code Standard Packing Reel ø180 mm = 3.000 Pieces/Reel Reel ø330 mm = 10.000 Pieces/Reel For symmetric types no defined Pin 1 orientation in reel. 0.2 2.7 8 4 Pin 1 marking 3.15 1.15 11 2010-01-15 BCR420U / BCR421U 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 (<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. 12 2010-01-15