Innovative Features Integrated in Hall Switches Increase System Quality, Safety and Control Application Note TLE4961-x/TLE4964-x/TLE4968-x Application Note Revision 1.0, 2012-07-16 Sense & Control Edition 2012-07-16 Published by Infineon Technologies AG 81726 Munich, Germany © 2012 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. Innovative Features Integrated in Hall Switches Revision History Page or Item Subjects (major changes since previous revision) Revision 1.0, 2012-07-16 <Revision X.Y>, <yyyy-mm-dd> Trademarks of Infineon Technologies AG AURIX™, C166™, CanPAK™, CIPOS™, CIPURSE™, EconoPACK™, CoolMOS™, CoolSET™, CORECONTROL™, CROSSAVE™, DAVE™, EasyPIM™, EconoBRIDGE™, EconoDUAL™, EconoPIM™, EiceDRIVER™, eupec™, FCOS™, HITFET™, HybridPACK™, I²RF™, ISOFACE™, IsoPACK™, MIPAQ™, ModSTACK™, my-d™, NovalithIC™, OptiMOS™, ORIGA™, PRIMARION™, PrimePACK™, PrimeSTACK™, PRO-SIL™, PROFET™, RASIC™, ReverSave™, SatRIC™, SIEGET™, SINDRION™, SIPMOS™, SmartLEWIS™, SOLID FLASH™, TEMPFET™, thinQ!™, TRENCHSTOP™, TriCore™. Other Trademarks Advance Design System™ (ADS) of Agilent Technologies, AMBA™, ARM™, MULTI-ICE™, KEIL™, PRIMECELL™, REALVIEW™, THUMB™, µVision™ of ARM Limited, UK. AUTOSAR™ is licensed by AUTOSAR development partnership. Bluetooth™ of Bluetooth SIG Inc. CAT-iq™ of DECT Forum. COLOSSUS™, FirstGPS™ of Trimble Navigation Ltd. EMV™ of EMVCo, LLC (Visa Holdings Inc.). EPCOS™ of Epcos AG. FLEXGO™ of Microsoft Corporation. FlexRay™ is licensed by FlexRay Consortium. HYPERTERMINAL™ of Hilgraeve Incorporated. IEC™ of Commission Electrotechnique Internationale. IrDA™ of Infrared Data Association Corporation. ISO™ of INTERNATIONAL ORGANIZATION FOR STANDARDIZATION. MATLAB™ of MathWorks, Inc. MAXIM™ of Maxim Integrated Products, Inc. MICROTEC™, NUCLEUS™ of Mentor Graphics Corporation. Mifare™ of NXP. MIPI™ of MIPI Alliance, Inc. 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 2011-02-24 Application Note 3 Revision 1.0, 2012-07-16 Innovative Features Integrated in Hall Switches Table of Contents Table of Contents Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1 1.1 1.2 1.3 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Overall Product Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Target Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Start-up Reset and Power-on Time tPON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 3 Default Start-up Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4 Shutdown Reset and Defined Output Shutdown Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5 Overtemperature and Overcurrent Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Application Note 4 7 7 7 7 Revision 1.0, 2012-07-16 Innovative Features Integrated in Hall Switches List of Figures List of Figures Figure 1-1 Figure 2-1 Figure 2-2 Figure 3-1 Figure 4-1 Figure 4-2 Figure 4-3 Figure 5-1 Figure 5-2 TLE496x-yK in the PG-SC59-3-5, TLE496x-yM in the PG-SOT23-3-15 and TLE496x-yL in the PGSSO-3-2 Package 7 Power-on With a Fast VDD Ramp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Power-on With a Slow VDD Ramp. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Exemplary Illustration of the Default Start-up of the TLE4961-x/TLE4964-x/TLE4968-x . . . . . . . . 10 Slow Output Shutdown Behavior at Existing Devices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Fast Output Shutdown Behavior and Shutdown Reset for the New Generation Hall Switches . . . 11 Example of a Functionality Test Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Case Temperature for a TLE496x-yK in the PG-SC59-3-5 and Short-circuited Output . . . . . . . . . 14 Case Temperature for a TLE496x-yL in the PG-SSO-3-2 and Short-circuited Output . . . . . . . . . . 14 Application Note 5 Revision 1.0, 2012-07-16 Innovative Features Integrated in Hall Switches List of Tables List of Tables Table 5-1 Absolute Maximum Rating Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Application Note 6 Revision 1.0, 2012-07-16 Innovative Features Integrated in Hall Switches Introduction 1 Introduction 1.1 Overview The TLE4961-x/TLE4964-x/TLE4968-x are parts of the new generation of high precision hall effect unipolar and bipolar switches and latches. They are equipped with highly accurate switching thresholds and an operating range form -40°C up to 170°C. To improve the reading of this document these various devices with different magnetic behaviors will be referred to as Hall Effect Switches or Hall Switches. Compared to the previous products some new features like the defined start-up behavior, start-up reset, shutdown reset and the overtemperature and overcurrent protection, were implemented. The functionality of these features are explained in this application note. 1.2 • • • • • • • • • • • • Overall Product Features 3.0 V to 32 V operating supply voltage Operation from unregulated power supply Reduced current consumption (1.6 mA) Overvoltage capability up to 42 V without external resistor Reverse polarity protection (-18 V) Output overcurrent & overtemperature protection Active error compensation High stability of magnetic thresholds High ESD performance (7 kV) SOT23 like SMD package PG-SC59-3-5 (TLE496x-yK) Leaded package PG-SSO-3-2 (TLE496x-yL) Small SMD package PG-SOT23-3-15 (TLE496x-yM) Figure 1-1 TLE496x-yK in the PG-SC59-3-5, TLE496x-yM in the PG-SOT23-3-15 and TLE496x-yL in the PG-SSO-3-2 Package 1.3 Target Applications Target applications for the TLE4961-x/TLE4964-x/TLE4968-x Hall switch family are all applications which require a high precision Hall switch with a operating temperature range from -40°C to 170°C. Its superior supply voltage range from 3.0 V to 32 V with overvoltage capability (e.g. load-dump) up to 42 V without external resistor makes it ideally suited for automotive and industrial applications. • • • The TLE4964-x family are unipolar switches with various different operating points. They are ideally suited for various position detection applications like in gear sticks, seats or HVAC. The TLE4961-x family are latches and suited for BLDC rotor position measurement or pole wheel applications, for index counting and or speed measurement. Index counting is often used in power closing applications like window lifters or sunroofs. The TLE4968-x has very low magnetic thresholds (very sensitive) and a bipolar switching behavior. It is therefore especially suited for applications which require a high sensitivity sensor. Applications are BLDC rotor position measurement or speed and position measurements in camshaft or transmission applications. Application Note 7 Revision 1.0, 2012-07-16 Innovative Features Integrated in Hall Switches Start-up Reset and Power-on Time tPON 2 Start-up Reset and Power-on Time tPON Start-up reset and start-up sequence When VDD is powered up it has to cross 2V to get the voltage regulator to start. Then the internal supply voltage VDDA is following VDD. With VDD reaching the specified minimal level of 3V an active start-up sequence is triggered. The device and the output transistor are set to a defined state by VDDA crossing the internal reset voltage level. Two different start-up sequences of the device are illustrated with exemplary slopes shown in Figure 2-2 and Figure 2-1. Depending on the ramp of the applied supply voltage tPON can vary between 55μs and smaller. Going to extremes, a minimum value in the range of the internal signal delay time td, (15μs to 20μs) could be reached. V 3V ±0. 05 V 2.4 2V 1V VDD V DD min crossed VDDA V DDA reset level 40µs 15µs t tPON VQ tPON tON Q td Output valid (switching) t Power-on reset executed Figure 2-1 Power-on With a Fast VDD Ramp V 3V ±0. 05 2.4 V 2V VDD V DD min crossed 1V V DDA reset level VDDA <40µs 15µs t tPON Output valid (switching) Q VQ td t PON Power -on reset executed tON t Figure 2-2 Power-on With a Slow VDD Ramp These startup mechanisms ensure a safe and predictable power-on behavior of the new Hall Switches family, providing a big advantage for the customers system design. Application Note 8 Revision 1.0, 2012-07-16 Innovative Features Integrated in Hall Switches Start-up Reset and Power-on Time tPON Power on time TPON definition The power-on time tPON is defined as follows: Time from applying the external supply voltage VDD = 3.0 V to the sensor until the output is valid in respect to the magnetic input. To specify tPON the following conditions: VDD = 3 V, B ≤ BRP - 0.5 mT or B ≥ BOP + 0.5 mT have to be fulfilled. The power-on time is a combination of the time frame for the internal circuitry powering up and the additional internal signal delay time td as explained on page 9. Application Note 9 Revision 1.0, 2012-07-16 Innovative Features Integrated in Hall Switches Default Start-up Behavior 3 Default Start-up Behavior The start-up behavior is one very important operating condition for sensors like hall effect switches. Not only the power on time (tPON) is of importance but as well the behavior of the output signal. Compared to other integrated circuits for sensors the behavior is always effected by a stimulus, the input signal which is intended to be sensed. For Hall Switches there are three different conditions of importance (see Figure 3-1). • • • The magnetic field is above the Operating Points (BOP) threshold B > BOP The magnetic field is below the Release Points (BRP) threshold B < BRP The magnetic field is in between the Operating Points (BOP) and the Release Points (BRP) thresholds within hysteresis BOP > B > BRP To avoid the uncertainty of the random startup in previous devices, a so called “default power on” state was defined. This means the device is, independent from the stimulus (actual magnet field applied), starting up in the logical “ZERO” state, which means the VQ pin is at the pull up voltage level. After a certain startup time the device is reacting according to the applied magnetic field. If the BOP threshold is exceeded, the logical “ONE” state, which means the VQ pin is at the low voltage level is applied. VDDA t Pon 3V The device always applies VQ level at start -up Power on ramp VQ t independent from the applied magnetic field ! Magnetic field above threshold B > BOP t VQ Magnetic field below threshold B < BRP t VQ Magnetic field in hysteresis BOP > B > BRP t Figure 3-1 Exemplary Illustration of the Default Start-up of the TLE4961-x/TLE4964-x/TLE4968-x Application Note 10 Revision 1.0, 2012-07-16 Innovative Features Integrated in Hall Switches Shutdown Reset and Defined Output Shutdown Behavior 4 Shutdown Reset and Defined Output Shutdown Behavior Complementary to the defined start-up behavior and start-up reset a defined shutdown and shutdown reset was implemented in the new generation Hall Switches. The advantage of this feature is to have the fast discharge of the output transistor and the option for a better test functionality. Compared to existing devices which show some capacitive discharging behavior at the output pin (see Figure 4-1), VDD V VQ 2V 1V t t1 , VDD disconnected tQoff up to 50ms Figure 4-1 Slow Output Shutdown Behavior at Existing Devices the new generation Hall Switches have a second internal reset functionality implemented. Once the shutdown reset level of 2.1± 0.05 V (different to the power-on reset level of 2.4±0.05 V) is crossed, a fast discharge of the output transistor is triggered (see Figure 4-2). This enables to have the VQ level reached at the output pin in around 5μs, compared to the tens of milliseconds of other devices. VQ (= default) level reached before VDD = 0V V 3V 2.1 ±0. 05 2V VQ VS V t3, output driver discharged actively 1V t t1 , VS tQoff disconnected ~ 5µs t 2, internal reset voltage level crossed Figure 4-2 Fast Output Shutdown Behavior and Shutdown Reset for the New Generation Hall Switches Application Note 11 Revision 1.0, 2012-07-16 Innovative Features Integrated in Hall Switches Shutdown Reset and Defined Output Shutdown Behavior In system functionality test example To use this shutdown behavior for functionality tests in the system, one could think of following scenario. It’s necessary to have a magnetic flux applied. • • • Then VDD has to be disconnected. The output will be at VQ level within 5 μs. Powering VDD up, the Output will go back to the 0 V level after the power on time (tPON, see Chapter 2). VDD disconnected => Q pin reaches VQ level (logical [LOW]) V 3V 2.1 ±0.05 2V VDD VQ V 1V t VDD reapplied => Q pin reaches VQsat level (logical [HIGH]) Figure 4-3 Example of a Functionality Test Timing Diagram Application Note 12 Revision 1.0, 2012-07-16 Innovative Features Integrated in Hall Switches Overtemperature and Overcurrent Protection 5 Overtemperature and Overcurrent Protection This feature was implemented to prevent a fast destruction of the sensor and to increase the robustness of the device. In combination of the improved high voltage capability and ESD robustness this was an essential addition for the targeted high quality standard. As shown in the Maximum Ratings Table in the Data Sheets, here Table 5-1, the junction temperature has a big influence regarding the lifetime. Table 5-1 Absolute Maximum Rating Parameters Parameter Symbol Values Min. Supply voltage Output voltage VDD VQ Typ. Unit Note / Test Condition Max. -18 0 32 42 V 32 V 10h, no external resistor required Reverse output current IQ -70 Junction temperature1) TJ -40 155 165 175 195 °C Storage temperature TS -40 150 °C Thermal resistance Junction ambient RthJA 300 200 300 K/W for PG-SC59-3-5 (2s2p) for PG-SSO-3-2 (2s2p) for PG-SOT23-3-15 (2s2p) Thermal resistance Junction lead RthJL 100 150 100 K/W for PG-SC59-3-5 for PG-SSO-3-2 for PG-SOT23-3-15 mA for 2000h (not additive) for 1000h (not additive) for 168h (not additive) for 3 x 1h (additive) 1) This lifetime statement is an anticipation based on an extrapolation of Infineon’s qualification test results. The actual lifetime of a component depends on its form of application and type of use etc. and may deviate from such statement. The lifetime statement shall in no event extend the agreed warranty period. Calculation of the dissipated power PDIS and junction temperature TJ of the chip (SC59 example): e.g for: VDD = 12 V, IS = 2.5mA, VQSAT = 0.5 V, IQ = 20mA Power dissipation: PDIS = 12 V x 2.5mA + 0.5 V x 20mA = 30mW + 10mW = 40mW Temperature ∆T = RthJA x PDIS = 300K/W x 40mW = 12K For TA = 150°C: TJ = TA + ∆T = 150°C + 12K = 162°C Application Note 13 Revision 1.0, 2012-07-16 Innovative Features Integrated in Hall Switches Overtemperature and Overcurrent Protection The case temperature (Tcase) reaches a maximum after some tens of seconds in the short circuit condition. But in fact the junction temperature (TJ) crossed the internal shutdown temperature of 192°C after some hundred milliseconds. The further increasing case temperature reflects the device starting to toggle between the shutdown TJ of 192°C and the cut-in TJ of 180°C at around 120Hz at 25°C ambient temperature. Note: Following plots show measurements of Tcase of the PG-SC59-3-5 and the PG-SSO-3-2 package. A remarkable difference between Tcase and TJ should be kept in mind. Although the chip is already in thermal shutdowm, the Tcase is relatively slowly increasing to a maximum level much lower then the TJ shutdown value. Figure 5-1 Case Temperature for a TLE496x-yK in the PG-SC59-3-5 and Short-circuited Output Figure 5-2 Case Temperature for a TLE496x-yL in the PG-SSO-3-2 and Short-circuited Output Application Note 14 Revision 1.0, 2012-07-16 w w w . i n f i n e o n . c o m Published by Infineon Technologies AG