LED Driver with Adjustable Current TLE 4241 GM Features • • • • • • • • • Adjustable constant output current Wide input voltage range Low drop voltage Open load detection Overtemperature protection Short circuit proof Reverse polarity proof Wide temperature range: -40 °C < Tj < 150 °C Very small SMD-Package P-DSO-8-3, -6, -7, -8, -9 Functional Description The TLE 4241 GM is an integrated adjustable constant current source. It provides an output current adjustable via different means (SET, PWM, reference resistor) which is kept nearly independent from load and supply voltage changes. The IC is designed to supply LEDs under the severe conditions of automotive applications resulting in constant brightness and extended LED lifetime. It is provided in the very small P-DSO-8-9 (Micro 8) package. Protection circuits prevent damage to the device in case of overload, short circuit, reverse polarity and overtemperature. The connected LEDs are protected against reverse polarity as well as excess voltages up to 45 V. A status output allows handling of open load and short circuit at the main output. A PWM input offers the possibility to adjust the LED brightness by pulse width modulation. With an implemented high/low current switch the output current level can be reduced e.g. for brake/tail light application. The implemented features such as adjustable output current, the high/low current switch and the provided PWM input make the device well suited for a broad range of LED and other applications. Type Ordering Code Package TLE 4241 GM Q67006-A9644 P-DSO-8-9 Data Sheet 1 Rev. 1.2, 2004-04-13 TLE 4241 GM Circuit Description Q ST Status I Regulation High SET Reference Voltage GND Figure 1 V/I Converter PWM Control Regulation Low REF AEB03003 Block Diagram An internal reference voltage of typ. 1.20 V supplies the REF pin which is connected to GND via an external resistor. In the SET = H mode the reference current flowing on the REF pin is mirrored with an amplification to form the desired output current. The typ. output current in the SET = H mode calculates: 1.20 I Q, typ /mA = ---------------------- × 487 + 0.1 R REF /kΩ (1) The output current is shown as a function of the reference resistance on Page 10 for the high as well as for the low current mode. With the PWM input the LED brightness can be regulated via duty cycle. Also PWM = L sets the TLE 4241 in sleep mode resulting in a very low current consumption of << 1 µA typ. Due to the high impedance of the PWM input (see timing diagram IPWM versus VPWM on Page 12) the PWM pin can thus also be used as an Enable input. Data Sheet 2 Rev. 1.2, 2004-04-13 TLE 4241 GM GND 1 8 I ST 2 7 Q PWM 3 6 REF SET 4 5 GND AEP03002 Figure 2 Pin Configuration (top view) Table 1 Pin Definitions and Functions Pin No. Symbol Function 1 GND Ground; internally connected to pin 5 2 ST Status Output; open collector output, connect to external pull-up resistor (10 kΩ or higher) 3 PWM Pulse Width Modulation Input; if not needed connect to VI 4 SET High/Low Current Input; choice of current level 5 GND Ground; internally connected to pin 1 6 REF Reference Input; connect to GND via an external resistor to adjust the output current 7 Q Output 8 I Input; block to GND directly at the IC with a 100 nF ceramic capacitor Data Sheet 3 Rev. 1.2, 2004-04-13 TLE 4241 GM Application Information W RO VBatt TLE 4271 100 nF 22 µF 10 k Ω WD VQ R ST µC PWM I TLE 4241G SET Q R REF LA E67B OSRAM AED03098 Figure 3 Application Circuit Figure 3 shows a typical application with the TLE 4241 GM LED driver. The 3 LEDs are driven with an adequate supply current adjusted by the resistor RREF. Thus brightness variations due to forward voltage spread of the LEDs are prevented. The luminosity spread arising from the LED production process can be compensated via software by an appropriate duty cycle applied to the PWM pin. Hence selection of the LEDs to forward voltage as well as to luminosity classes can be spared. The slightly negative temperature coefficient of the TLE 4241 GM output current protects the LEDs against overtemperature stress if the IC is placed nearby the LEDs. The voltage drop (VI - VQ) across the TLE 4241 GM is monitored in order to detect an open load condition indicated at the status output pin ST. In case of open load, the voltage drop will decrease below the lower status switching threshold Vdr,L. Hence, the status output ST will be driven low. In normal operation, the voltage drop is above the upper status threshold Vdr,H, thus the open collector output ST is in high-ohmic state (see also section Status Output at the Electrical Characteristics). The function of ST, SET and PWM as well as their timings are shown in Figure 4. Data Sheet 4 Rev. 1.2, 2004-04-13 TLE 4241 GM VI t VPWM VPWM, H VPWM, L t VSET VSET, H VSET, L tPWM, OFF tSET, L IQ t tPWM, ON tSET, H mA 47 10 Open Load VST t VSTL t AET03339.VSD Figure 4 Data Sheet Function and Timing Diagram 5 Rev. 1.2, 2004-04-13 TLE 4241 GM Table 2 Absolute Maximum Ratings -40 °C < Tj < 150 °C Parameter Symbol Limit Values Unit Remarks Min. Max. VI II -42 45 V – – – mA internally limited VQ IQ -1 40 V – – – mA internally limited VST IST -0.3 40 V – –5 5 mA internally limited VREF IREF -0.3 7 V – -2 2 mA – Input Voltage Current Output Voltage Current Status Output Voltage Current Reference Input Voltage Current Pulse Width Modulation Input Voltage VPWM -40 40 V – Current – -1 1 mA – VSET ISET -40 40 V – -1 1 mA – Tj Tstg -40 150 °C – -50 150 °C – Rthja – 105 K/W High/Low Current Input Voltage Current Temperatures Junction temperature Storage temperature Thermal Resistances Junction ambient 1) 1) Worst case regarding peak temperature; mounted on PCB 80 × 80 × 1.5 mm , 35 µm Cu, 300 mm2 heat sink area. 3 Note: Maximum ratings are absolute ratings; exceeding any one of these values may cause irreversible damage to the integrated circuit. Data Sheet 6 Rev. 1.2, 2004-04-13 TLE 4241 GM Table 3 Operating Range Parameter Input voltage Status output voltage SET voltage PWM voltage Junction temperature Reference Resistor Data Sheet Symbol VI VST VSET VPWM Tj RREF Limit Values Unit Remarks Min. Max. 4 45 V – – 16 V – 0 40 V – 0 40 V – -40 150 °C – 7 100 kΩ SET = H 4.7 18 kΩ SET = L 7 Rev. 1.2, 2004-04-13 TLE 4241 GM Table 4 Electrical Characteristics 9 V ≤ VI ≤ 16 V; RREF = 10 kΩ; VPWM ≥ VPWM,H; -40 °C < Tj < 150 °C; all voltages with respect to ground; positive current defined flowing into pin; unless otherwise specified Parameter Symbol Limit Values Min. Typ. Max. Unit Test Condition Current consumption off mode IqOFF – 0.1 2 µA PWM = L, TJ < 85 °C; VI ≤ 13.5 V Current consumption IqL IqH IqL,O – 5 10 mA SET = L; VQ = 6 V – 6 10 mA SET = H; VQ = 6 V – – 10 mA SET = L; VQ open IqH,O – – 10 mA SET = H; VQ open Current consumption Current consumption open load Current consumption open load Output Output current IQ Output current IQ Current Ratio IQH/IQL IQmax IQmax Vdr Output current limit Output current limit Drop voltage 6.7 8.4 10 mA SET = L, VQ = 6 V – 8.6 – mA SET = L, VQ = 4 V 47 58.5 70 mA SET = H, VQ = 6 V – 60.0 – mA SET = H, VQ = 4 V 6 7 8 – – – 83 – mA SET = L; RREF = 0 Ω – 83 – mA SET = H; RREF = 0 Ω – 0.2 0.5 V SET = L; IQ = 80% of IQ,nom,L Drop voltage Vdr – 0.3 0.5 V SET = H; IQ = 80% of IQ,nom,H PWM Input VPWM,H VPWM,L IPWM,H 2.0 – – V – – – 0.5 V – – 220 500 µA VPWM = 5.0 V PWM input current low level IPWM,L -10 – 10 µA VPWM = 0.0 V Turn on delay time tPWM,ON 0 5 30 µs 20%/80% IQ, see Figure 4 PWM high level PWM low level PWM input current high level Data Sheet 8 Rev. 1.2, 2004-04-13 TLE 4241 GM Table 4 Electrical Characteristics (cont’d) 9 V ≤ VI ≤ 16 V; RREF = 10 kΩ; VPWM ≥ VPWM,H; -40 °C < Tj < 150 °C; all voltages with respect to ground; positive current defined flowing into pin; unless otherwise specified Parameter Symbol Limit Values Min. Unit Test Condition Typ. Max. tPWM,OFF 0 10 30 VSET,H VSET,L ISET,H 2.0 – – V – – – 0.5 V – – 220 500 µA VSET = 5.0 V SET input current low level ISET,L -10 – 10 µA VSET = 0.0 V Delay time L -> H tSET,H – – 30 µs 20%/80% IQ, see Figure 4 Delay time H -> L tSET,L – – 30 µs 20%/80% IQ, see Figure 4 Vdr,L 0.15 – – V (VI - VQ) decreasing SET = L 0.15 – – V (VI - VQ) decreasing SET = H – – 0.7 V (VI - VQ) increasing SET = L – – 0.7 V (VI - VQ) increasing SET = H Turn off delay time µs 20%/80% IQ, see Figure 4 SET Input SET high level SET low level SET input current high level Status Output Lower status switching threshold Upper status switching threshold Vdr,H Status low voltage VSTL – – 0.4 V (VI - VQ) < Vdr,L IST = 1.0 mA Leakage current ISTLK – – 10 µA (VI - VQ) > Vdr,H VST = 5.0 V Data Sheet 9 Rev. 1.2, 2004-04-13 TLE 4241 GM Typical Performance Characteristics Output Current versus External Resistor, SET = L Output Current versus External Resistor, SET = H AED03333.VSD 100 IQ mA IQ mA SET = H VQ = 6 V 80 16 70 14 60 12 50 10 40 8 30 6 20 4 10 2 0 5 10 0 50 kΩ 100 20 AED03334.VSD 20 SET = L VQ = 6 V 5 10 50 kΩ 100 20 RREF RREF Output Current versus Supply Voltage, SET = L Output Current versus Supply Voltage, SET = H AED03335.VSD 100 IQ mA IQ mA VQ = 6 V RREF = 10 kΩ 80 14 60 12 50 10 40 8 30 6 20 4 10 2 0 5 10 15 20 25 30 0 V 40 VI Data Sheet VQ = 6 V RREF = 10 kΩ 16 SET = H 70 0 AED03336.VSD 20 SET = L 0 5 10 15 20 25 30 V 40 VI 10 Rev. 1.2, 2004-04-13 TLE 4241 GM Reference Voltage versus Junction Temperature AED03340.VSD 1.25 VREF V RREF = 10 kΩ 1.23 1.21 1.19 1.17 1.15 -40 0 40 80 °C 160 Tj Data Sheet 11 Rev. 1.2, 2004-04-13 TLE 4241 GM PWM Pin Input Current versus PWM Voltage IPWM PWM Pin Input Current versus PWM Voltage AED03332.VSD 2.0 mA IPWM 1.5 300 1.0 200 0.5 100 0 0 5 10 15 20 25 30 0 V 40 AED03331.VSD 400 µA 0 1 2 3 4 5 6 VPWM SET Pin Input Current versus SET Voltage SET Pin Input Current versus SET Voltage AED03338.VSD 2.5 V 8 VPWM ISET mA ISET AED03337.VSD 400 µA 2.0 300 1.5 200 1.0 100 0.5 0 0 5 10 15 20 25 30 0 V 40 Data Sheet 0 1 2 3 4 5 6 V 8 VSET VSET 12 Rev. 1.2, 2004-04-13 TLE 4241 GM Package Outlines 1.27 0.1 0.41 +0.1 -0.05 +0.05 -0.01 0.2 C 0.64 ±0.25 0.2 M A C x8 8 5 Index Marking 1 4 5 -0.21) 8˚ MAX. 4 -0.21) 1.75 MAX. 0.1 MIN. (1.5) 0.33 ±0.08 x 45˚ 6 ±0.2 A Index Marking (Chamfer) 1) Does not include plastic or metal protrusion of 0.15 max. per side GPS09032 Figure 5 P-DSO-8-9 (Plastic Dual Small Outline) You can find all of our packages, sorts of packing and others in our Infineon Internet Page “Products”: http://www.infineon.com/products. Dimensions in mm SMD = Surface Mounted Device Data Sheet 13 Rev. 1.2, 2004-04-13 TLE 4241 GM Revision History Version Date Changes Rev. 1.2 2004-04-13 Page 4, 9: Improved indication and explanation of the open load detection function. Data Sheet 14 Rev. 1.2, 2004-04-13 Edition 2004-04-13 Published by Infineon Technologies AG, St.-Martin-Strasse 53, 81669 München, Germany © Infineon Technologies AG 2004. All Rights Reserved. Attention please! The information herein is given to describe certain components and shall not be considered as a guarantee of characteristics. Terms of delivery and rights to technical change reserved. 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