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5-V Low Drop Fixed Voltage Regulator TLE 4278 G Features * * * * * * * * * * * * Output voltage tolerance 2% Very low current consumption Separated reset and watchdog output Low-drop voltage Watchdog Adjustable watchdog activating threshold Adjustable reset threshold Overtemperature protection Reverse polarity protection Short-circuit proof Suitable for use in automotive electronics Wide temperature range P-DSO-14-3, -8, -9, -11, 14 Functional Description The TLE 4278 is a monolithic integrated low-drop fixed output voltage regulator supplying loads up to 200 mA. The IC is available in a P-DSO-14-8 package. It is designed to supply microprocessor systems under the severe conditions of automotive applications and therefore equipped with additional protection functions against overload, short circuit and overtemperature. The TLE 4278 can also be used in other applications where a stabilized voltage is required. An input voltage VI in the range of 5.5 V VI 45 V is regulated to VQ,nom = 5 V with an accuracy of 2%. The device operates in the wide temperature range of Tj = -40 to 150 C. Two additional features are implemented in the TLE 4278 a load dependent watchdog function as well as a sophisticated reset function including power on reset, under voltage reset, adjustable reset delay time and adjustable reset switching threshold. The watchdog function monitors the microcontroller, including time base failures. In case of a missing rising edge within a certain pulse repetition time the watchdog output is set Type TLE 4278 G Data Sheet Ordering Code Q67007-A9291 1 Package P-DSO-14-8 Rev. 1.3, 2005-04-29 TLE 4278 G to LOW. Programming of the max. repetition time can be done easily by an external reset delay capacitor. To prevent a reset in case of missing pulses, the watchdog output WO is separate from the reset output RO for the TLE 4278. The watchdog output can be used as an interrupt signal for the microcontroller. In any case it is possible to connect pin WO and pin RO externally. When the controller is set to sleep mode or low power mode its current consumption drops and no watchdog pulses are created. In order to avoid unnecessary wake-up signals due to missing pulses at pin WI the watchdog feature can be disabled as a function of the load current. The switch off threshold is set by an external resistor to pin WADJ. The watchdog function can also be used as a timer, which periodically wakes up the controller. Therefore the pin WADJ has to be connected to the output Q. The power on reset feature is necessary for a defined start of the microprocessor when switching on the application. The reset signal at pin RO goes high after a certain delay timed trd when the output voltage of the regulator has surpassed the reset threshold. The delay time is set by the external delay capacitor. An under voltage reset circuit supervises the output voltage. In case VQ falls below the reset threshold the reset output is set to LOW after a short reset reaction time trr. The reset LOW signal is generated down to an output voltage VQ of 1 V. In addition the reset switching threshold can be adjusted by an external voltage divider. This feature is useful with microprocessors which guarantee a safe operation down to voltages below the internally set reset threshold of 4.65 V typical. Data Sheet 2 Rev. 1.3, 2005-04-29 TLE 4278 G P-DSO-14-8 WO WADJ GND GND GND D RADJ 1 2 3 4 5 6 7 14 13 12 11 10 9 8 AEP02113 RO V GND GND GND VQ W Figure 1 Table 1 Pin 1 2 Pin Configuration (top view) Pin Definitions and Functions Symbol Function WO WADJ Watchdog Output; the open collector output is connected to the 5 V output via an integrated resistor of 30 k. Watchdog Adjust; an external resistor to GND determines the watchdog activating threshold. Ground Reset Delay; connect a capacitor to ground for delay time adjustment. Reset Switching Threshold Adjust; for setting the switching threshold, connect a voltage divider from output to ground. If this input is connected to ground, the reset is triggered at the internal threshold. Watchdog Input; rising edge-triggered input for monitoring a microcontroller. 5 V Output Voltage; block to ground with min. 10 F capacitor, ESR 5 . Input Voltage; block to ground directly on the IC with ceramic capacitor. Reset Output; the open collector output is connected to the 5 V output via an integrated resistor of 30 k. 3, 4, 5, GND 10, 11, 12 6 7 D RADJ 8 9 13 14 WI Q I RO Data Sheet 3 Rev. 1.3, 2005-04-29 TLE 4278 G V 13 9 VQ Temperature Sensor Protection Circuit Reset Generator Control Amplifier 14 RO 7 1 RADJ WO D + - Bandgap Reference Watchdog 6 3-5, 10-12 GND 2 WADJ 8 W AEB02114 Figure 2 Block Diagram Data Sheet 4 Rev. 1.3, 2005-04-29 TLE 4278 G Table 2 Absolute Maximum Ratings Tj = -40 to 150 C Parameter Input Voltage I Voltage Current Output Voltage Q Voltage Current Reset Output RO Voltage Current Reset Delay D Voltage Current Voltage Current Watchdog Input WI Voltage Current Watchdog Output WO Voltage Current Watchdog Adjust WADJ Voltage Current Ground GND Current Symbol Limit Values Min. Max. 45 - 25 - 25 5 7 2 7 - 7 - 25 5 7 - 50 V mA V mA V mA V mA V mA V mA V mA V mA mA - Internally limited - Internally limited - - - - - Internally limited - Internally limited - - - Internally limited - Unit Notes VI II VQ IQ VRO IRO VD ID VRADJ IRADJ VWI IWI VWO IWO VWADJ IWADJ IGND -42 - -1 - -0.3 -5 -0.3 -2 -0.3 - -0.3 - -0.3 -5 -0.3 - -100 Reset Switching Threshold Adjust RADJ Data Sheet 5 Rev. 1.3, 2005-04-29 TLE 4278 G Table 2 Absolute Maximum Ratings (cont'd) Tj = -40 to 150 C Parameter Temperatures Junction temperature Storage temperature Symbol Limit Values Min. Max. 150 150 C C - - Unit Notes Tj Tstg -50 -50 Note: ESD protection according to MIL Std. 883: 2 kV. Maximum ratings are absolute ratings; exceeding any one of these values may cause irreversible damage to the integrated circuit. Table 3 Parameter Input voltage Junction temperature Thermal Resistance Junction ambient Junction pin Operating Range Symbol Limit Values Min. Max. 45 150 80 30 V C K/W K/W - - 1) Unit Notes VI Tj Rthj-a Rthj-pin 5.5 -40 - - 3 Measured to pin 4 2 1) Package mounted on PCB 80 x 80 x 1.5 mm ; 35 Cu; 5 Sn; Heat Sink Area 6 cm ; zero airflow. Note: In the operating range the functions given in the circuit description are fulfilled. Data Sheet 6 Rev. 1.3, 2005-04-29 TLE 4278 G Table 4 Electrical Characteristics VI = 13.5 V; -40 C Tj 125 C (unless otherwise specified) Parameter Output voltage Output voltage Symbol Limit Values Min. Typ. 5.00 5.0 400 180 210 5 0.25 -5 5 Max. 5.10 5.2 - 200 230 12 0.5 - 20 V V mA A A mA V mV mV 0 mA IQ 150 mA; 6 V VI 28 V 1 mA IQ 50 mA; 28 V VI 45 V 4.90 4.8 200 - - - - -30 - Unit Test Condition VQ VQ Output current limiting IQ Current consumption Iq = II - IQ Current consumption Iq = II - IQ Current consumption Iq = II - IQ Drop voltage VDR = VI - VQ Load regulation Line regulation Reset Generator Reset threshold Reset headroom Iq,o Iq,o Iq,150 Vdr VQ.lo VQ,li VQ = 4.8 V Tj = 25 C; IQ = 0 mA IQ = 0 mA; Tj = 85 C IQ = 150 mA IQ = 150 mA1) IQ = 5 to 150 mA; VI = 6 V VI = 6 to 28 V IQ = 5 mA RADJ connected to GND VQ,rt 4.5 4.65 350 4.8 - V mV VQ,rt = 180 (VQ,nom VQ,rt) 1.28 - 4.5 20 2 IQ = 10 mA VQ 3.5 V Rext = 10 k to VQ VQ 1 V - Internal connected to VQ Reset adjust threshold VRADJ,th Reset low voltage Reset high voltage Reset pull-up Charging current 1.35 0.20 - 30 5 1.45 0.40 - 45 8 V V V k A VRO,l VRO,h RRO ID,c VD = 1.0 V Data Sheet 7 Rev. 1.3, 2005-04-29 TLE 4278 G Table 4 Electrical Characteristics (cont'd) VI = 13.5 V; -40 C Tj 125 C (unless otherwise specified) Parameter Symbol Limit Values Min. Upper timing threshold VDU Lower reset timing threshold Delay time Reset reaction time Watchdog Activating threshold Current ratio Slew rate 1.5 0.2 12 0.4 Typ. 1.9 0.3 20 1.0 1.35 720 - 0.2 - 30 5 1.3 1.9 0.7 60 13 47 Max. 2.3 0.4 28 2.0 1.45 800 - 0.4 - 45 8 2.0 2.3 0.9 80 19 61 V V ms s V - V V k A A V V ms ms ms - - Unit Test Condition VDRL trd trr CD = 47 nF CD = 47 nF Voltage at WADJ VWADJ,th 1.28 IQ/IWADJ 650 dVWI/dt 5 - 4.5 20 2 0.6 1.5 0.5 42 7 35 IQ 10 mA Rext > 10 k to VQ - Internal connected to VQ V/s From 20% up to 80% VQ Watchdog low voltage VWOL Watchdog high voltage VWOH RWO Charge current ID,wc Discharge current ID,wd Upper timing threshold VDU Lower watchdog VDWL Watchdog pull-up timing threshold Watchdog output pulse period Watchdog output low time TWD,p VD = 1.0 V VD = 1.0 V - - Cd = 47 nF VQ > VRT Cd = 47 nF tWD,l Watchdog trigger time TWI,tr 1) Measured when the output voltage VQ has dropped 100 mV from the nominal value. Data Sheet 8 Rev. 1.3, 2005-04-29 TLE 4278 G C 1 1000 F WO V VWO VWADJ C 2 470 nF V 13 9 VQ Q CQ 10 F WO WADJ WADJ W 1 2 8 6 D TLE 4278 G 3-5, 10-12 GND CD 47 nF RO 14 7 RADJ RO VRO VQ VW VD GND VRE AES02115 VDR = V -VO Outside the control range Figure 3 Test Circuit Data Sheet 9 Rev. 1.3, 2005-04-29 TLE 4278 G Application Information Input, Output The input capacitors CI1 and CI2 are necessary for compensating line influences. Using a resistor of approx. 1 in series with CI1, the LC circuit of input inductance and input capacitance can be damped. To stabilize the regulation circuit the output capacitor CQ is necessary. Stability is guaranteed at values CQ 10 F with an ESR 5 within the operating temperature range. +12 V C 1 C2 V 470 nF 13 9 VQ R1 CQ 22 F 1 WO RO W RADJ TLE 4278G 3-5, 10-12 GND Cooling Area CD 14 8 P *) 6 D 7 2 WADJ 47 nF R WADJ R2 *) or short to GND for internal threshold AES02116 Figure 4 Application Circuit Data Sheet 10 Rev. 1.3, 2005-04-29 TLE 4278 G Reset Timing The power-on reset delay time is defined by the charging time of an external capacitor CD which can be calculated as follows: CD = (trd x ID,c)/V Definitions: * * * * * (1) CD = delay capacitor trd = delay time ID,c = charge current, typical 5 A V = VDU, typical 1.9 V VDU = upper delay switching threshold at CD for reset delay time The reset reaction time trr is the time it takes the voltage regulator to set the reset out LOW after the output voltage has dropped below the reset threshold. It is typically 1 s for delay capacitor of 47 nF. For other values for CD the reaction time can be estimated using Equation (2): trr 20 s/F x CD V (2) VQ < t rr V Q, rt d V D,c = dt CD t t V DU V DRL VD VRO t rd t rr t t Power-on-Reset Thermal Shutdown Voltage Dip at Input Undervoltage Secondary Spike Overload at Output AED03010 Figure 5 Reset Timing (watchdog disabled) Data Sheet 11 Rev. 1.3, 2005-04-29 TLE 4278 G Reset Switching Threshold The present default value is 4.65 V. When using the TLE 4278 the reset threshold can be set to 3.5 V < VQ,rt < 4.6 V by connecting an external voltage divider to pin RADJ. The calculation can be easily done since the reset adjust input current can be neglected. If this feature is not needed, the pin has to be connected to GND. VQ,rt = Vref x (1 + R1/R2) Definitions: * * (3) VQ,rt = Reset threshold Vref = comparator reference voltage, typical 1.35 V (Reset adjust input current 50 nA) TLE 4278 G 13 9 Q 30 k 14 Band-GapReference 1.35 V >1 Band-GapReference 1.35 V RO + - R1 7 3 ... 5, 10 ... 12 GND R2 RADJ AES03071 Figure 6 The reset output pin is internally connected to the 5 V output Q via a 30 k pull-up resistor. Down to an output voltage VQ of typical 1 V the reset LOW signal at pin RO is generated. For the timing of the reset feature please refer to Figure 5. Data Sheet 12 Rev. 1.3, 2005-04-29 TLE 4278 G Watchdog Activating The calculation of the external resistor which adjusts the watchdog switch off threshold can be done by Equation (4): RWADJ = VWADJ,th x (IQ/IWADJ)/IQ,act Definitions: * * * (4) VWADJ,th = switch off threshold, typical 1.35 V IQ/IWADJ = current ratio, typical 720 IQ,act = switch off load current TLE 4278 G Q Band-GapReference HIGH Watchdog active LOW Watchdog disabled WADJ + - R WADJ GND AES03072 Figure 7 Data Sheet 13 Rev. 1.3, 2005-04-29 TLE 4278 G Watchdog Timing The frequency of the watchdog pulses has to be higher than the minimum pulse sequence which is set by the external reset delay capacitor CD. Calculation can be done according to the formulas given in Figure 8. The watchdog output is internally connected to the output Q via a 30 k pull-up resistor. To generate a watchdog created reset signal for the microcontroller the pin WO can be connected to the reset input of the microcontroller. It is also allowed to parallel the watchdog out to the reset out. VW V t VQ T WD, p t VD VDU VDWL VWO T WI, tr t t WD, L t T WI, tr = (VDU - VDWL ) D, wd C D ; T WD, p = (VDU -VDWL ) ( D, wc + D, wd ) D, wc x D, wd C D ; t WD, L = (VDU - VDWL ) t CD AED03099 D, wc Figure 8 Timing of the Watchdog Function Data Sheet 14 Rev. 1.3, 2005-04-29 TLE 4278 G Table 5 Symbol RO D RADJ WI WO WADJ Hints for Unused Pins Function Reset output Reset delay Reset switching threshold adjust Watchdog input Watchdog output Watchdog adjust Connect to open open or to output Q GND GND open to output Q via a 270 k resistor: Watchdog always active 2) to GND: Watchdog disabled 1) Data Sheet 15 Rev. 1.3, 2005-04-29 TLE 4278 G Drop Voltage Vdr versus Output Current IQ mV V dr 700 600 500 400 Tj = 125 C 300 Tj = 25 C 200 100 0 AED01544 Current Consumption Iq versus Output Current IQ TL E42 7 8_ IQ -IQ .VSD I q [mA] V I = 13.5V T j = 25C 10 1 0.1 0 50 100 150 200 250 mA 0.01 0.1 1 10 100 IQ [mA] Q Current Consumption Iq versus Input Voltage VI 12 AED01546 Output Voltage VQ versus Input Voltage VI mA VQ 10 AED01547 Iq mA 10 Tj = 25 C 8 8 6 R L= 33 6 R L= 33 4 4 R L= 50 2 R L= 100 0 10 20 30 40 V 50 VI 2 0 0 0 2 4 6 8 V V Data Sheet 16 Rev. 1.3, 2005-04-29 TLE 4278 G Charge Current ID,wc and Discharge Current ID,wd versus Temperature Tj 8 A 7 6 5 4 3 2 1 0 -40 AED03111 Switching Voltage VDU, VDWL and VDRL versus Temperature Tj VD 3.2 V 2.8 V = 13.5 V 2.4 AED03055 V = 13.5 V VD = 1.0 V D, wc 2.0 1.6 1.2 0.8 0.4 0 -40 V DU D, wd V DWL V DRL 0 40 80 120 Tj C 0 40 80 120 C 160 Tj Output Voltage VQ versus Temperature Tj 5.2 VQ V 5.1 V = 13.5 V 5.0 AED03056 Output Current Limit IQ versus Input Voltage VI 500 AED03057 IQ mA 400 Tj = 25 C 300 4.9 200 4.8 4.7 100 4.6 -40 0 0 40 80 120 C 160 Tj 0 10 20 30 40 V 50 VI Data Sheet 17 Rev. 1.3, 2005-04-29 TLE 4278 G Package Outlines 0.33 0.08 x 45 1.75 MAX. 4 -0.2 1) 0.1 MIN. (1.5) 1.27 0.41 +0.1 -0.06 14 0.2 M 8 0.1 A C 14x C 6 0.2 0.64 0.25 1 7 1) 8.75 -0.2 A Index Marking 1) Does not include plastic or metal protrusion of 0.15 max. per side 8 MAX. 0.2 +0.05 -0.01 GPS09033 Figure 9 P-DSO-14-8 (Plastic Dual Small Outline) Revision History Version Rev. 1.2 Rev. 1.3 Date 2004-01-01 2005-04-29 Changes Final Data Sheet * Typ. Perf. Char. Graph "Iq vs. IQ": Replaced by a logarithmic graph in order to precise at low IQ. * Order number typo corrected You can find all of our packages, sorts of packing and others in our Infineon Internet Page "Products": http://www.infineon.com/products. SMD = Surface Mounted Device Data Sheet 18 Dimensions in mm Rev. 1.3, 2005-04-29 Edition 2005-04-29 Published by Infineon Technologies AG, St.-Martin-Strasse 53, 81669 Munchen, Germany (c) Infineon Technologies AG 2005. 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. We hereby disclaim any and all warranties, including but not limited to warranties of non-infringement, regarding circuits, descriptions and charts stated herein. Information For further information on technology, delivery terms and conditions and prices please contact your 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 your nearest Infineon Technologies Office. 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