BCR402R LED Driver Supplies stable bias current even at low battery voltage Low voltage drop of 0.75V Ideal for stabilizing bias current of LEDs Negative temperature coefficient protects LEDs against thermal overload 4 1 3 2 EHA07188 Type Marking BCR402R W6s Pin Configuration 1 = GND 2 = Iout 3 = VS Package 4 = Rext SOT143R Maximum Ratings Parameter Symbol Source 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 = 87 °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 190 K/W 1For calculation of R thJA please refer to Application Note Thermal Resistance 1 Aug-29-2001 BCR402R Electrical Characteristics at TA=25°C, unless otherwise specified Parameter Symbol Values Unit min. typ. max. IS 350 440 540 µA Iout 18 20 22 mA VSmin - 1.4 - Voltage drop (VS - VCE) Iout = 20 mA Vdrop - 0.75 - Output current change versus TA Iout/Iout - -0.3 - %/K Iout/Iout - 2 - %/V Characteristics Supply current VS = 10 V Output current VS = 10 V, Vout = 7.6 V DC Characteristics with stabilized LED load Lowest sufficient battery voltage overhead V Iout > 18mA VS = 10 V Output current change versus VS VS = 10 V 2 Aug-29-2001 BCR402R Output current versus supply voltage Total power dissipation Ptot = f(TS) Iout = f (VS ); Rext = Parameter Load: two LEDs with VF = 3.8V in series 10 -1 500 mW A Iout P tot Rext = 68 Ohm 300 Rext = open 10 -2 200 100 0 0 20 40 60 80 100 120 °C 10 -3 0 150 2 4 6 8 10 12 14 TS 16 V 20 VS Supply current versus supply voltage Application Circuit: IS = f(VS) +Vs BCR 402R Load: two LEDs with VF = 3.8V in series 3 10 -3 Rext Vdrop 4 IS A 10 -4 1 2 Is 10 -5 0 2 4 6 8 10 12 14 16 V Iout 20 VS 3 Aug-29-2001