ILD4035E6327HTSA1

LED Drivers for High Power LEDs ILD4035 350 mA Step Down LED Driver Data Sheet Revision 2.0, 2011-08-17 Industrial and Multimarket Edition 2011-08-17 Published by Infineon Technologies AG 81726 Munich, Germany © 2011 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. ILD4035 350 mA Step Down LED Driver Revision History Page or Item Subjects (major changes since previous revision) Revision 2.0, 2011-08-17 Table 2 Maximum peak current specified for hysteretic peak condition Table 2 Maximum junction temperature increased to 150 °C Figure 3 Safe operating area increased Table 4 Maximum supply voltage reduced to 40 V Table 4 Overall current consumption and standby current reduced Table 4 Over temperature protection improved from flicker to sloped behaviour Table 5 Application setup changed Table 6 Voltage range of digital control signals changed Chapter 6.3 Over temperature protection improved from flicker to sloped behaviour Chapter 6.4 Figures of switching parameters changed Revision 1.0, 2010-11-11 Trademarks of Infineon Technologies AG AURIX™, BlueMoon™, C166™, CanPAK™, CIPOS™, CIPURSE™, COMNEON™, EconoPACK™, CoolMOS™, CoolSET™, CORECONTROL™, CROSSAVE™, DAVE™, EasyPIM™, EconoBRIDGE™, EconoDUAL™, EconoPIM™, EiceDRIVER™, eupec™, FCOS™, HITFET™, HybridPACK™, I²RF™, ISOFACE™, IsoPACK™, MIPAQ™, ModSTACK™, my-d™, NovalithIC™, OmniTune™, OptiMOS™, ORIGA™, PRIMARION™, PrimePACK™, PrimeSTACK™, PRO-SIL™, PROFET™, RASIC™, ReverSave™, SatRIC™, SIEGET™, SINDRION™, SIPMOS™, SMARTi™, SmartLEWIS™, SOLID FLASH™, TEMPFET™, thinQ!™, TRENCHSTOP™, TriCore™, X-GOLD™, X-PMU™, XMM™, XPOSYS™. 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MIPS™ of MIPS Technologies, Inc., USA. muRata™ of MURATA MANUFACTURING CO., MICROWAVE OFFICE™ (MWO) of Applied Wave Research Inc., OmniVision™ of OmniVision Technologies, Inc. Openwave™ Openwave Systems Inc. RED HAT™ Red Hat, Inc. RFMD™ RF Micro Devices, Inc. SIRIUS™ of Sirius Satellite Radio Inc. SOLARIS™ of Sun Microsystems, Inc. SPANSION™ of Spansion LLC Ltd. Symbian™ of Symbian Software Limited. TAIYO YUDEN™ of Taiyo Yuden Co. TEAKLITE™ of CEVA, Inc. TEKTRONIX™ of Tektronix Inc. TOKO™ of TOKO KABUSHIKI KAISHA TA. UNIX™ of X/Open Company Limited. VERILOG™, PALLADIUM™ of Cadence Design Systems, Inc. VLYNQ™ of Texas Instruments Incorporated. VXWORKS™, WIND RIVER™ of WIND RIVER SYSTEMS, INC. ZETEX™ of Diodes Zetex Limited. Last Trademarks Update 2010-10-26 Data Sheet 3 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Table of Contents Table of Contents Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2 Product Brief . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3 Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 4 Thermal Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 5 5.1 5.2 5.3 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Switching Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Digital Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 14 15 15 6 6.1 6.2 6.3 6.4 Basic Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Setting the average LED current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dimming of the LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Temperature Protection Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Switching Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 16 16 19 19 7 Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 8 Evaluation Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 9 Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Data Sheet 4 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver List of Figures List of Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Data Sheet Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Total Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Safe Operating Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 PWM Dimming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 ILD4035 on Evaluation Board. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Package Outline SC74 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Recommended PCB Footprint for Reflow Soldering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Tape Loading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 5 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver List of Tables List of Tables Table 1 Table 2 Table 3 Table 4 Table 5 Table 6 Data Sheet Pin Definition and Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum Thermal Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Switching Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Digital Control Parameter at Pin EN/PWM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 10 11 12 14 15 15 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver List of Tables Data Sheet 7 Revision 2.0, 2011-08-17 350 mA Step Down LED Driver with Internal Switch ILD4035 1 • • • • • • • • • • • • • Features Wide input voltage range: 4.5 V ... 40 V Internal switch for up to 400 mA average LED current Up to 95 % efficiency Over current protection Over voltage protection Temperature protection mechanism Inherent open-circuit LED protection Soft-start capability Low shut down current Analog and PWM dimming possible Typical 3 % output current accuracy Minimum external components required Small package: SC74 SC74-3D Applications • • • • LED driver for general lighting applications Retail, office and residential luminaires and downlights LED replacement lamps Architectural lighting Product Name Package ILD4035 SC74-6-4 Data Sheet Pin Configuration 1 = VS 2 = GND 3 = EN 8 Marking 4 = Vswitch 5 = GND 6 = Vsense 35 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Product Brief 2 Product Brief The ILD4035 is a hysteretic step down LED driver IC for general lighting applications, which is capable to drive high power LEDs with average currents up to 400 mA. The IC incorporates a wide input voltage range and an internal power switch. The output current level can be adjusted with an external sense resistor. According to the multifunctional control pin the IC can be switched on and off by an external signal, which is also suitable to regulate brightness of the LEDs by PWM or analog voltage dimming. Depending on the value of the switching inductor the switching frequency and the voltage ripple can be set. The precise internal bandgap stabilizes the circuit and provides stable current conditions over temperature range. To ensure a long lifetime of the LED system, the ILD4035 incorporates an overvoltage and an overcurrent protection. In addition, the integrated thermal protection will reduce the output current to protect the LEDs and the IC against thermal stress. ILD4035 Buck LED Converter VS 1 Vstab Vstab 6 Vsense 5 GND 4 Vswitch I/V Over Voltage Protection GND 2 TPC Vref Vstab Vstab Vstab EN / PWM 3 Over Current Protection ILD4035_ Block diagram.vsd Figure 1 Data Sheet Block Diagram 9 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Product Brief Pin Definition Table 1 Pin Definition and Function Pin No. Name Pin Type Buffer Type Function 1 Vs Input – Supply voltage 2 GND GND – IC ground 3 EN / PWM Input – Multifunctional pin: • Chip enable signal • Analog dimming signal • PWM dimming signal 4 Vswitch Output – Power switch output 5 GND GND – IC ground 6 Vsense Input – LED current sense input Data Sheet 10 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Maximum Ratings 3 Maximum Ratings Table 2 Maximum Ratings Parameter Symbol Values Min. Typ. Max. Unit Note / Test Condition Supply voltage VS – – 45 V – Peak output current ISwitch – – 550 mA Hysteretic peak current Total power dissipation, Ts ≤ 85°C Ptot – – 1000 mW – Junction temperature TJ – – 150 °C – Storage temperature range TSTG -65 – 150 °C – ESD capability at all pins VESD HBM kV – – 4 HBM acc. to JESD22-A114 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. Data Sheet 11 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Thermal Characteristics 4 Thermal Characteristics Table 3 Maximum Thermal Resistance Parameter Symbol 1) Junction - soldering point Values RthJS Min. Typ. Max. – – 65 Unit Note / Test Condition K/W – 1) For calculation of RthJA please refer to application note AN077 (Thermal Resistance Calculation) 1.2 1 Ptot [W] 0.8 0.6 0.4 0.2 0 Figure 2 0 20 40 60 80 TS [°C] 100 120 140 160 Total Power Dissipation Equation (1) is gives an estimation for the power dissipation of ILD4035. Ptot = 1 .1V ⋅ I LED ⋅ duty cycle + f Switch ⋅ 1 µW ⋅ I LED 350 mA (1) Data Sheet 12 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Thermal Characteristics 45 40 VS - VΣfLED [V] 35 30 47 μH 68 μH 100 μH 150 μH 220 μH 330 μH 25 20 15 10 5 0 0.05 Figure 3 0.1 0.15 0.2 0.25 0.3 0.35 Average LED current ILED [A] 0.4 0.45 Safe Operating Area Figure 3 shows the safe operating area for the respective inductance values. The safe operating area consists of the minimum and maximum allowed average LED current and the resulting voltage overhead. The voltage overhead Voverhead is the difference between the supply voltage VS and the sum of the LED forward voltages VΣfLED. Example calculation 1 3 LEDs in series, VfLED= 3V, ILED = 350 mA, VS = 12 V Voverhead = VS - VΣfLED = 12 V - 9 V = 3 V → any of the above coil values can be used Example calculation 2 6 LEDs in series, VfLED= 3V, ILED = 250 mA, VS = 24 V Voverhead = VS - VΣfLED = 24 V - 18 V = 6 V → the coil values needs to be at least 68 µH Outside the safe operating area the switching frequency, hysteretic peak current and associated power dissipation Ptot of ILD4035 will increase beyond the maximum ratings. Data Sheet 13 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Electrical Characteristics 5 Electrical Characteristics 5.1 DC Characteristics All parameters at TA = 25 °C, unless otherwise specified. VS = 12 V, 3 LEDs, Rsense = 303 mΩ (ILED = 375 mA), L = 100 μH, VEN = 3 V, VfLED = 3 V Table 4 DC Characteristics Parameter Symbol Values Unit Min. Typ. Max. Note / Test Condition Supply voltage VS 4.5 – 40 V Overall current consumption open load IS open load 1.4 2.3 3.1 mA VS = 4.5 V ILED = 0 mA Overall current consumption open load IS open load 1.5 2.4 3.2 mA VS = 12 V ILED = 0 mA Overall current consumption open load IS open load 1.8 3.0 3.9 mA VS = 40 V ILED = 0 mA Overall standby current consumption IS standby – – 1 µA VEN = 0 V; VS = 12 V Overall standby current consumption IS standby – – 5 μA VEN = 0 V; VS = 40 V Enable voltage for standby mode VEN -0.3 – 0.4 V Enable voltage for analog dimming VEN 1 – 2 V linear dimming range – 50 140 μA VEN = 3 V VS = 4.5..40 V Input current of multifunctional control IEN pin Current of sense input Isense – 20 – μA at any LED current Over temperature protection TS,TSD – 113 – °C TS for 10 % ILED reduction, defined by TJ Data Sheet 14 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Electrical Characteristics 5.2 Switching Characteristics All parameters at TA = 25 °C, unless otherwise specified. VS = 12 V, 3 LEDs, Rsense = 303 mΩ (ILED = 375 mA), L = 100 μH, VEN = 3 V, VfLED = 3 V Table 5 Switching Characteristics Parameter Symbol Values Unit Min. Typ. Max. Switching frequency fSwitch – 120 – kHz Maximum switching frequency fSwitch max – – 500 kHz – 114 – mV Vsensehys – ±7.5 – % Residual voltage at collector of power Vswitch on transistor – 1.1 – V – ±3 – % Mean current sense threshold voltage Vsense Sense threshold hysteresis Output current accuracy 5.3 Ioutacc Note / Test Condition for any coil value output switch turned on Digital Signals All parameters at TA = 25 °C, unless otherwise specified. Table 6 Digital Control Parameter at Pin EN/PWM Parameter Symbol Values Min. Typ. Max. Unit Note / Test Condition full LED current Input voltage for power on VOn 2.5 3 40 V Input voltage for power off VOff -0.3 – 0.4 V Min. power on puls duration tOn 10 – Data Sheet 15 µs Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Basic Application Information 6 Basic Application Information This section covers the basic information required for calculating the parameters for a certain LED application. For detailed application information please check the Application Note AN215 (Driving 1 W LEDs with ILD4035) or visit our web site http://www.infineon.com/led.appnotes 6.1 Setting the average LED current The average output current for the LEDs is set by the external sense resistor Rsense. To calculate the value of this resistor a first approximation can be calculated using Equation (2). Vsense is dependent on the supply voltage VS and the number of LEDs in series. Rsense = Vsense I LED (2) Example calculation 1 VS = 12 V, 100 µH, VfLED = 3 V, 3 LEDs in series → Vsense = 114 mV ILED = 375 mA → Rsense = 303 mΩ Example calculation 2 VS = 24 V, 100 µH, VfLED = 3 V, 6 LEDs in series → Vsense = 106 mV ILED = 350 mA → Rsense = 303 mΩ An easy way to achieve these resistor values is to connect standard resistors in parallel 6.2 Dimming of the LEDs Analog voltage dimming The voltage level of the EN/PWM pin can be used for analog dimming of the LED current. To achieve a linear change in LED current versus control voltage the recommended voltage range at the EN/PWM pin is 1 V to 2 V. The maximum achievable LED current is defined by resistor Rsense. The maximum LED current will be achieved for VEN ≥ 2.5 V. Below 0.4 V the ILD4035 is set to standby mode and the output is switched off. The typical dimming performance is shown in below figures. Data Sheet 16 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Basic Application Information ILED versus VEN, TA=25 °C 0.4 ILED (relative) versus VEN, TA=25 °C 110 303 mΩ, 100 μH 333 mΩ, 100 μH 600 mΩ, 100 μH 1200 mΩ, 220 μH 0.3 303 mΩ, 100 μH 333 mΩ, 100 μH 600 mΩ, 100 μH 1200 mΩ, 220 μH 100 90 80 ILED [%] ILED [A] 70 0.2 60 50 40 30 0.1 20 10 0 1 1.5 2 VEN [V] 2.5 3 2.5 3 0 1 1.5 2 VEN [V] 2.5 3 ILED versus VEN, 333 mΩ, 100 µH 0.4 -40 °C 25 °C 85 °C 105 °C 0.35 ILED [A] 0.3 0.25 0.2 0.15 0.1 0.05 0 1 1.5 2 VEN [V] PWM Dimming Besides the analog dimming functionality the EN/PWM pin acts as input for a pulse width modulated (PWM) signal to control the dimming of the LED string. For PWM dimming the signal's logic high level should be at least 2.5 V and the PWM frequency should be lower than 5 kHz. For the ILD4035/4001 demo board a dimming frequency less than 330 Hz is recommended to maintain a maximum contrast ratio of 100:1. The achieveable contrast ratio is shown on Figure 4 based on the measured average LED current deviating 3 dB from the linear reference. The maximum contrast ratio depends mainly on the rise time of the inductor current and is thus dependent on supply voltage, inductor size and LED string forward voltage. Data Sheet 17 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Basic Application Information Contrast Ratio 1000 100 10 1 100 1000 10000 PWM Dimming Frequency [Hz] Figure 4 Data Sheet PWM Dimming 18 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Basic Application Information 6.3 Temperature Protection Circuit ILD4035 incorporates a temperature protection circuit referring to the junction temperature of ILD4035. The higher the junction temperature of ILD4035 the lower the current of the LEDs. This feature helps to reduce the power dissipation of ILD4035 and the LEDs. Yet still the product specific maximum ratings for junction temperature need to be observed to avoid a permanent damage of the devices. ILD4035 has been characterized on ILD4035/4001 application board heated from the backside without additional air flow on the circuit board surface besides natural convection. Design and layout of the circuit board as well as the air flow influence the thermal resistance junction to ambient RthJA of ILD4035 and thus its junction temperature. Below figures show the LED current versus soldering point temperature TS. LED current versus TS, VS = 12 V LED current (relative) versus TS, VS = 12 V 0.4 110 0.35 0.3 100 ILED [%] ILED [A] 0.25 0.2 0.15 0.1 90 80 0.05 0 40 50 60 303 mΩ, 100 μH 333 mΩ, 100 μH 6.4 70 80 90 TS [°C ] 100 110 120 70 130 600 mΩ, 100 μH 1200 mΩ, 220 μH 40 50 60 303 mΩ, 100 μH 333 mΩ, 100 μH 70 80 90 TS [°C ] 100 110 120 130 600 mΩ, 100 μH 1200 mΩ, 220 μH Switching Parameters For all shown parameters ILD4035 has been measured on evaluation board ILD4035/4001 at TA = 25 °C. Used LEDs have a typical forward voltage VfLED of 3 V. For details see application note AN215 (Driving 1W LEDs with ILD4035) or visit our web site http://www.infineon.com/lowcostleddrivers. Data Sheet 19 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Basic Application Information Rsense = 303 mΩ, L= 47 µH ILED versus VS and Number of LEDs fSwitch versus VS and Number of LEDs 0.45 500 400 fSwitch [kHz] ILED [A] 0.4 0.35 0.3 0.25 300 200 100 0 5 10 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 0 45 10 LEDs 0 5 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs Efficiency versus VS and Number of LEDs 10 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 45 10 LEDs Duty Cycle versus VS and Number of LEDs 100 100 95 80 Duty Cycle [%] Efficiency [%] 90 85 80 75 70 60 40 20 65 60 0 1 LED 2 LEDs 3 LEDs Data Sheet 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 0 45 10 LEDs 0 1 LED 2 LEDs 3 LEDs 20 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 45 10 LEDs Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Basic Application Information Rsense = 303 mΩ, L= 68 µH ILED versus VS and Number of LEDs fSwitch versus VS and Number of LEDs 0.45 500 400 fSwitch [kHz] ILED [A] 0.4 0.35 0.3 0.25 300 200 100 0 5 10 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 0 45 10 LEDs 0 5 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs Efficiency versus VS and Number of LEDs 10 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 45 10 LEDs Duty Cycle versus VS and Number of LEDs 100 100 95 80 Duty Cycle [%] Efficiency [%] 90 85 80 75 70 60 40 20 65 60 0 1 LED 2 LEDs 3 LEDs Data Sheet 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 0 45 10 LEDs 0 1 LED 2 LEDs 3 LEDs 21 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 45 10 LEDs Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Basic Application Information Rsense = 303 mΩ, L= 100 µH ILED versus VS and Number of LEDs fSwitch versus VS and Number of LEDs 0.45 500 400 fSwitch [kHz] ILED [A] 0.4 0.35 0.3 0.25 300 200 100 0 5 10 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 0 45 10 LEDs 0 5 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs Efficiency versus VS and Number of LEDs 10 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 45 10 LEDs Duty Cycle versus VS and Number of LEDs 100 100 95 80 Duty Cycle [%] Efficiency [%] 90 85 80 75 70 60 40 20 65 60 0 1 LED 2 LEDs 3 LEDs Data Sheet 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 0 45 10 LEDs 0 1 LED 2 LEDs 3 LEDs 22 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 45 10 LEDs Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Basic Application Information Rsense = 303 mΩ, L= 220 µH ILED versus VS and Number of LEDs fSwitch versus VS and Number of LEDs 0.45 500 400 fSwitch [kHz] ILED [A] 0.4 0.35 0.3 0.25 300 200 100 0 5 10 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 0 45 10 LEDs 0 5 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs Efficiency versus VS and Number of LEDs 10 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 45 10 LEDs Duty Cycle versus VS and Number of LEDs 100 100 95 80 Duty Cycle [%] Efficiency [%] 90 85 80 75 70 60 40 20 65 60 0 1 LED 2 LEDs 3 LEDs Data Sheet 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 0 45 10 LEDs 0 1 LED 2 LEDs 3 LEDs 23 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 45 10 LEDs Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Basic Application Information Rsense = 367 mΩ, L= 47 µH ILED versus VS and Number of LEDs fSwitch versus VS and Number of LEDs 0.4 500 400 fSwitch [kHz] ILED [A] 0.35 0.3 0.25 0.2 300 200 100 0 5 10 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 0 45 10 LEDs 0 5 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs Efficiency versus VS and Number of LEDs 10 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 45 10 LEDs Duty Cycle versus VS and Number of LEDs 100 100 95 80 Duty Cycle [%] Efficiency [%] 90 85 80 75 70 60 40 20 65 60 0 1 LED 2 LEDs 3 LEDs Data Sheet 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 0 45 10 LEDs 0 1 LED 2 LEDs 3 LEDs 24 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 45 10 LEDs Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Basic Application Information Rsense = 367 mΩ, L= 68 µH ILED versus VS and Number of LEDs fSwitch versus VS and Number of LEDs 0.4 500 400 fSwitch [kHz] ILED [A] 0.35 0.3 0.25 0.2 300 200 100 0 5 10 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 0 45 10 LEDs 0 5 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs Efficiency versus VS and Number of LEDs 10 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 45 10 LEDs Duty Cycle versus VS and Number of LEDs 100 100 95 80 Duty Cycle [%] Efficiency [%] 90 85 80 75 70 60 40 20 65 60 0 1 LED 2 LEDs 3 LEDs Data Sheet 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 0 45 10 LEDs 0 1 LED 2 LEDs 3 LEDs 25 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 45 10 LEDs Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Basic Application Information Rsense = 367 mΩ, L= 100 µH ILED versus VS and Number of LEDs fSwitch versus VS and Number of LEDs 0.4 500 400 fSwitch [kHz] ILED [A] 0.35 0.3 0.25 0.2 300 200 100 0 5 10 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 0 45 10 LEDs 0 5 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs Efficiency versus VS and Number of LEDs 10 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 45 10 LEDs Duty Cycle versus VS and Number of LEDs 100 100 95 80 Duty Cycle [%] Efficiency [%] 90 85 80 75 70 60 40 20 65 60 0 1 LED 2 LEDs 3 LEDs Data Sheet 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 0 45 10 LEDs 0 1 LED 2 LEDs 3 LEDs 26 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 45 10 LEDs Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Basic Application Information Rsense = 367 mΩ, L= 220 µH ILED versus VS and Number of LEDs fSwitch versus VS and Number of LEDs 0.4 500 400 fSwitch [kHz] ILED [A] 0.35 0.3 0.25 0.2 300 200 100 0 5 10 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 0 45 10 LEDs 0 5 15 4 LEDs 5 LEDs 6 LEDs 1 LED 2 LEDs 3 LEDs Efficiency versus VS and Number of LEDs 10 20 25 VS [V] 30 7 LEDs 8 LEDs 9 LEDs 35 40 45 10 LEDs Duty Cycle versus VS and Number of LEDs 100 100 95 80 Duty Cycle [%] Efficiency [%] 90 85 80 75 70 60 40 20 65 60 0 1 LED 2 LEDs 3 LEDs Data Sheet 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 0 45 10 LEDs 0 1 LED 2 LEDs 3 LEDs 27 5 10 15 4 LEDs 5 LEDs 6 LEDs 20 25 VS [V] 7 LEDs 8 LEDs 9 LEDs 30 35 40 45 10 LEDs Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Application Circuit 7 Application Circuit Rsense Vs 1 2 Vstab Vref 6 I/V TPC Vref Vstab 5 Vstab Vstab EN / PWM 3 Figure 5 Application Circuit 8 Evaluation Board Figure 6 ILD4035 on Evaluation Board Data Sheet 4 ILD4035 28 Revision 2.0, 2011-08-17 ILD4035 350 mA Step Down LED Driver Package Information Package Information 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 9 A B 6x M 0.1 MAX. 0.95 0.2 1.9 M A SC74-PO V04 Figure 7 Package Outline SC74 2.9 1.9 0.5 0.95 SC74-FPR V04 Figure 8 Recommended PCB Footprint for Reflow Soldering 0.2 2.7 8 4 Pin 1 marking Figure 9 Data Sheet 3.15 1.15 SC74-TP Tape Loading 29 Revision 2.0, 2011-08-17 w w w . i n f i n e o n . c o m Published by Infineon Technologies AG