TLE4921-3U

Dynamic Differential Hall Effect Sensor IC TLE 4921-3U Bipolar IC Features • • • • • • • • • • • • • • • Advanced performance High sensitivity Symmetrical thresholds High piezo resistivity Reduced power consumption South and north pole pre-induction possible AC coupled Digital output signal Two-wire and three-wire configuration possible Large temperature range Large airgap Low cut-off frequency Protection against overvoltage Protection against reversed polarity Output protection against electrical disturbances Marking 21C3U P-SSO-4-1 Type TLE 4921-3U Ordering Code Q67006-A9171 Package P-SSO-4-1 The differential Hall Effect sensor TLE 4921-3U provides a high sensitivity and a superior stability over temperature and symmetrical thresholds in order to achieve a stable duty cycle. TLE 4921-3U is particularly suitable for rotational speed detection and timing applications of ferromagnetic toothed wheels such as anti-lock braking systems, transmissions, crankshafts, etc. The integrated circuit (based on Hall effect) provides a digital signal output with frequency proportional to the speed of rotation. Unlike other rotational sensors differential Hall ICs are not influenced by radial vibration within the effective airgap of the sensor and require no external signal processing. Data Sheet 1 2000-07-01 TLE 4921-3U Pin Configuration (view on branded side of component) 2.67 1.53 Center of sensitive area ±0.15 2.5 1 2 3 4 VS Q GND C AEP01694 Figure 1 Pin Definitions and Functions Pin No. 1 2 3 4 Symbol Function Supply voltage Output Ground Capacitor VS Q GND C Data Sheet 2 2000-07-01 TLE 4921-3U VS 1 Protection Device Internal Reference and Supply Vreg (3V) Hall-Probes HighpassFilter SchmittTrigger Open Collector Protection Device Amplifier 2 Q 3 GND 4 CF AEB01695 Figure 2 Block Diagram Data Sheet 3 2000-07-01 TLE 4921-3U Functional Description The Differential Hall Sensor IC detects the motion and position of ferromagnetic and permanent magnet structures by measuring the differential flux density of the magnetic field. To detect ferromagnetic objects the magnetic field must be provided by a back biasing permanent magnet (south or north pole of the magnet attached to the rear unmarked side of the IC package). Using an external capacitor the generated Hall voltage signal is slowly adjusted via an active high pass filter with a low cut-off frequency. This causes the output to switch into a biased mode after a time constant is elapsed. The time constant is determined by the external capacitor. Filtering avoids aging and temperature influence from Schmitt-trigger input and eliminates device and magnetic offset. The TLE 4921-3U can be exploited to detect toothed wheel rotation in a rough environment. Jolts against the toothed wheel and ripple have no influence on the output signal. Furthermore, the TLE 4921-3U can be operated in a two-wire as well as in a three-wireconfiguration. The output is logic compatible by high/low levels regarding on and off. Circuit Description (see Figure 2) The TLE 4921-3U is comprised of a supply voltage reference, a pair of Hall probes spaced at 2.5 mm, differential amplifier, filter for offset compensation, Schmitt trigger, and an open collector output. The TLE 4921-3U was designed to have a wide range of application parameter variations. Differential fields up to ± 80 mT can be detected without influence to the switching performance. The pre-induction field can either come from a magnetic south or north pole, whereby the field strength up to 500 mT or more will not influence the switching points. The improved temperature compensation enables a superior sensitivity and accuracy over the temperature range. Finally the optimized piezo compensation and the integrated dynamic offset compensation enable easy manufacturing and elimination of magnet offsets. Protection is provided at the input/supply (pin 1) for overvoltage and reverse polarity and against overstress such as load dump, etc., in accordance with ISO-TR 7637 and DIN 40839. The output (pin 2) is protected against voltage peaks and electrical disturbances. Data Sheet 4 2000-07-01 TLE 4921-3U Absolute Maximum Ratings Tj = – 40 to 150 °C Parameter Supply voltage Output voltage Output current Output reverse current Capacitor voltage Junction temperature Junction temperature Junction temperature Junction temperature Storage temperature Thermal resistance P-SSO-4-1 Current through inputprotection device Current through outputprotection device Symbol Limit Values min. max. 30 30 50 50 3 150 160 170 210 150 190 200 200 V V mA mA V °C °C °C °C °C K/W mA mA – – – – – 5000 h 2500 h 1000 h 40 h – – – 35 – – – 0.3 – – – – – 40 – – – 1) Unit Remarks VS VQ IQ – IQ VC Tj Tj Tj Tj TS Rth JA ISZ IQZ – 0.7 t < 2 ms; v = 0.1 t < 2 ms; v = 0.1 Electro Magnetic Compatibility ref. DIN 40839 part 1; test circuit 1 Testpulse 1 Testpulse 2 Testpulse 3a Testpulse 3b Testpulse 4 Testpulse 5 1) VLD VLD VLD VLD VLD VLD – 100 100 – 150 100 –7 120 V V V V V V td = 2 ms td = 0.05 ms td = 0.1 µs td = 0.1 µs td ≤ 20 s td = 400 ms; RP = 400 Ω Reverse current < 10 mA Note: Stresses above those listed here may cause permanent damage to the device. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Data Sheet 5 2000-07-01 TLE 4921-3U Operating Range Parameter Supply voltage Junction temperature Pre-induction Symbol Limit Values min. max. 24 170 500 V °C mT – – at Hall probe; independent of magnet orientation – 4.5 – 40 – 500 Unit Remarks VS Tj B0 ∆B Differential induction – 80 80 mT Note: In the operating range the functions given in the circuit description are fulfilled. AC/DC Characteristics Parameter Supply current Symbol Limit Values min. typ. max. 6.1 6.7 8.0 8.8 mA mA V µA mT 4.7 5.1 Output saturation voltage Output leakage current Center of switching points: (∆BOP + ∆BRP) / 2 Operate point Release point Hysteresis Unit Test Condition Test Circuit 1 1 1 1 IS VQSat IQL ∆Bm – – –1 0.25 0.6 – 0 10 1 VQ = high IQ = 0 mA VQ = low IQ = 40 mA IQ = 40 mA VQ = 24 V – 20 mT < ∆B < 2 20 mT 1) 2) f = 200 Hz ∆BOP ∆BRP ∆BHy – 0 0.5 – – 1.5 0 – 2.5 mT mT mT f = 200 Hz, ∆B = 20 mT f = 200 Hz, ∆B = 20 mT f = 200 Hz, ∆B = 20 mT IS = 16 mA IS = 16 mA IQ = 40 mA CL = 10 pF 2 2 2 Overvoltage protection at supply VSZ voltage at output VQZ Output rise time 27 27 – – – – 35 35 0.5 V V µs 1 1 1 tr Data Sheet 6 2000-07-01 TLE 4921-3U AC/DC Characteristics (cont’d) Parameter Output fall time Delay time3) Symbol Limit Values min. typ. max. – – – 0 40 –4 – – – 0.5 25 10 15 48 – 2.2 0.1 0.1 µs µs µs µs kΩ mV/ mT V mT mT – – – – 32 – 0.8 4) Unit Test Condition Test Circuit 1 2 tf tdop tdrp tdop - tdrp RC SC VC f ∆ Bm ∆BHy IQ = 40 mA CL = 10 pF f = 10 kHz ∆B = 5 mT 25 °C ± 2 °C – ∆B = 0 ∆B = 5 mT F=2N Filter input resistance Filter sensitivity to ∆B Filter bias voltage Frequency Resistivity against mechanical stress (piezo) 1) 1 1 1 2 25) 20000 Hz – 0.1 – 0.1 Leakage currents at pin 4 should be avoided. The bias shift of Bm caused by a leakage current IL can be I L × RC ( T ) calculated by:∆ B m = ----------------------------- . SC ( T ) 2) 3) 4) For higher ∆B the values may exceed the limits like following | ∆Bm | < | 0.05 × ∆B | For definition see page 16. 1 Depends on filter capacitor CF. The cut-off frequency is given by f = ---------------------------------- . The switching points are 2 π × RC × C F guaranteed over the whole frequency range, but amplitude modification and phase shift due to the 1st order highpass filter have to be taken into account. 5) See page 17. Note: The listed characteristics are ensured over the operating range of the integrated circuit. Typical characteristics specify mean values expected over the production spread. If not otherwise specified, typical characteristics apply at Tj = 25 °C and the given supply voltage. Data Sheet 7 2000-07-01 TLE 4921-3U RP 300 Ω V SZ 1 ΙS VS RL VLD 4.7 nF VS ΙC 1) 4 C Q 2 Ι Q , Ι QR VC GND 3 V QSat , V QZ CL 1) RC = ∆VC ∆Ι C AES01696 Figure 3 Test Circuit 1 1 VS 1 kΩ 2 f min f max ∆ B OP ∆ B Hy AES01258 VS 4 C Q VQ CF 470 nF GND 3 Figure 4 Test Circuit 2 Data Sheet 8 2000-07-01 TLE 4921-3U Application Configurations Two possible applications are shown in Figure 7 and 8 (Toothed and Magnet Wheel). The difference between two-wire and three-wire application is shown in Figure 9. Gear Tooth Sensing In the case of ferromagnetic toothed wheel application the IC has to be biased by the south or north pole of a permanent magnet (e.g. SmCO5 (Vacuumschmelze VX145) with the dimensions 8 mm × 5 mm × 3 mm) which should cover both Hall probes. The maximum air gap depends on – the magnetic field strength (magnet used; pre-induction) and – the toothed wheel that is used (dimensions, material, etc.; resulting differential field) a centered distance of Hall probes b Hall probes to IC surface L IC surface to tooth wheel L N S b a a = 2.5 mm b = 0.3 mm AEA01259 Figure 5 Sensor Spacing T Conversion DIN – ASA m = 25.4 mm/p T = 25.4 mm CP AEA01260 d DIN d z m T ASA diameter (mm) number of teeth module m = d/z (mm) pitch T = π × m (mm) Toothed Wheel Dimensions p diameter pitch p circular pitch = z/d (inch) PD CP pitch diameter PD = z/p (inch) CP = 1 inch × π/p Figure 6 Data Sheet 9 2000-07-01 TLE 4921-3U Gear Wheel Hall Sensor 1 Hall Sensor 2 Signal Processing Circuitry S (N) N (S) Permanent Magnet AEA01261 Figure 7 TLE 4921-3U, with Ferromagnetic Toothed Wheel Magnet Wheel S N Hall Sensor 1 S Hall Sensor 2 Signal Processing Circuitry AEA01262 Figure 8 Data Sheet TLE 4921-3U, with Magnet Wheel 10 2000-07-01 TLE 4921-3U Two-wire-application Line 1 VS C GND 3 Q VS RL 2 4 CF 470 nF VSIGNAL RS Sensor for example : R L = 330 Ω R S = 120 Ω Mainframe AES01263 Three-wire-application Rp 1 VS C GND 3 Q Line VS RL 4 2 4.7 nF 4.7 nF VSIGNAL CF 470 nF Sensor for example : R L = 330 Ω R P = 0 ... 330 Ω Mainframe AES01264 Figure 9 Application Circuits Data Sheet 11 2000-07-01 TLE 4921-3U N (S) S (N) 1 B1 Wheel Profile B2 Missing Tooth 4 Magnetic Field Difference ∆ B = B2-B1 Small Airgap Large Airgap ∆ B RP = 0.75 mT ∆ B HYS ∆ B OP = -0.75 mT Output Signal VQ Operate point : B2 - B1 < ∆ B OP switches the output ON (VQ = LOW) Release point : B2 - B1 > ∆ B RP switches the output OFF (VQ = HIGH) ∆ B RP = ∆ BOP + ∆ B HYS The magnetic field is defined as positive if the south pole of the magnet shows towards the rear side of the IC housing. AED01697 Figure 10 System Operation Data Sheet 12 2000-07-01 TLE 4921-3U Quiescent Current versus Supply Voltage 10.0 AED01698 Quiescent Current versus Temperature 10.0 AED01699 ΙS mA 7.5 Ι Q ON = 40 mA Ι S ON Ι S OFF ΙS mA 7.5 Ι Q ON = 40 mA Ι S ON Ι S OFF 5.0 5.0 2.5 2.5 Ι S diff 0 0 5 10 15 V 25 0 -50 0 50 100 ˚C 200 VS Ta Quiescent Current Difference versus Temperature 1.0 ∆Ι S mA 0.75 AED01700 Quiescent Current versus Output Current 10.0 AED01701 ΙS Ι Q ON = 40 mA mA 7.5 VS = 12 V Ι S ON - Ι S OFF 0.5 Ι S ON 5.0 0.25 2.5 0 0 5 10 15 V 25 0 0 10 20 30 mA 50 VS ΙQ Data Sheet 13 2000-07-01 TLE 4921-3U Saturation Voltage versus Temperature Saturation Voltage versus Output Current 0.3 AED01703 0.4 AED01702 VQ V 0.3 VS = 4.5 V Ι Q = 50 mA VQ V 0.2 0.1 0 Ta = 25 ˚C 0.2 -0.1 -0.2 -0.3 0 -50 0.1 0 50 100 ˚C 200 -0.4 -50 -30 -10 10 30 mA 50 Ta ΙQ Saturation Voltage versus Supply Voltage 0.4 AED01704 Switching Points versus Preinduction 2.0 mT 1.5 -80 mT < ∆ B < 80 mT AED01705 VQ V 0.3 Ι Q = 40 mA Ta = 25 ˚C BRP, (-B OP ) 0.2 1.0 typ 0.1 0.5 0 0 5 10 15 V 25 0 -500 -250 0 mT 500 VS BO Data Sheet 14 2000-07-01 TLE 4921-3U Switching Induction versus Temperature 2 AED01706 Hysteresis versus Temperature AED01707 3.5 Bm mT 1 B m = ( B OP + B RP ) /2 f = 200 Hz max B HY mT 2.5 B HY = B RP - B OP f = 200 Hz max 0 typ typ 1.5 -1 min 0.5 min -2 -50 0 50 100 ˚C 200 0 -50 0 50 100 ˚C 200 Ta Ta Minimum Switching Field versus Frequency 3.0 AED01708 Minimum Switching Field versus Frequency 3.5 AED01709 B min mT 2.5 C = 940 nF B min mT 3.0 2.5 C = 940 nF 2.0 2.0 1.5 1.5 1.0 Ta = -40 ˚C Ta = 170 ˚C 1.0 0.5 0 0.001 0.5 Ta = 25 ˚C Ta = 150 ˚C 0 0.001 0.01 0.1 1 kHz 100 0.01 0.1 1 kHz 100 f f Data Sheet 15 2000-07-01 TLE 4921-3U Delay Time1) between Switching Threshold ∆B and Falling Edge of VQ at Tj = 25 °C 30 AED01710 Delay Time1) between Switching Threshold ∆B and Rising Edge of VQ at Tj = 25 °C 30 AED01711 t dop µ s 25 t drp µ s B RP t drp BOP t dop 25 20 20 15 15 ∆ B = 1.2 mT 10 ∆ B = 1.2 mT 10 ∆ B = 5 mT 5 5 ∆ B = 5 mT 0 0 0 1) 5 10 15 kHz 25 0 1) 5 10 15 kHz 25 f f Delay Time versus Differential Field 30 AED01712 Delay Time versus Temperature 30 AED01713 t d µs 25 f = 10 kHz t d µs 25 f = 10 kHz ∆ B = 2 mT 20 20 t d op 15 15 10 10 t d op 5 t d rp 5 t d rp 0 0 20 40 60 mT ∆B 100 0 -50 0 50 100 ˚C 200 Ta 1) Switching points related to initial measurement @∆B = 2 mT, f = 200 Hz Data Sheet 16 2000-07-01 TLE 4921-3U Rise and Fall Time versus Temperature AED01714 Rise and Fall Time versus Output Current 120 AED01715 t 100 ns 90 80 70 60 50 40 30 20 10 0 -50 0 t ns 100 Ι Q = 40 mA Ta = 25 ˚C 80 tf tr 60 tr 40 tf 20 50 100 ˚C 200 0 0 10 20 30 mA 50 Ta ΙQ Capacitor Voltage versus Temperature AED01716 Switching Thresholds versus Mechanical Stress 1.0 mT 0.9 AED01717 3.0 VC V 2.5 ∆ B RP ,(− ∆ B OP ) F r = 0.5 2.0 typ 1.5 0.8 max min 0.7 1.0 0.6 0.5 0 -50 0 50 100 ˚C 200 0.5 0 1 2 3 N 5 Ta F Data Sheet 17 2000-07-01 TLE 4921-3U Filter Sensitivity versus Temperature AED01718 Filter Input Resistance versus Temperature RC R C (25 ˚C) 2 AED01719 -5 S C mV mT -4 typ -3 VS = 12 V 1.5 max min 1 -2 0.5 -1 0 -50 0 50 100 ˚C 200 0 -50 0 50 100 ˚C 200 Ta Ta Delay Time for Power on (VS Switching from 0 V to 4.5 V) tpon versus Temp. 0.35 k ms nF 0.30 0.25 0.20 0.15 0.10 0.05 0 -50 min AED02646 max 0 50 100 C 200 Ta Data Sheet 18 2000-07-01 TLE 4921-3U Package Outlines P-SSO-4-1 (Plastic Single Small Outline Package) 0.15 max. 5.38 ±0.05 5.16 ±0.08 1 max. 0.2 1.9 max. 12.7 ±1 1x45˚ 1 -0.1 0.25 ±0.05 3.38 ±0.06 3.71 ±0.08 (0.25) 0.6 max. 23.8 ±0.5 38 max. 0.2 +0.1 1 -1 18 ±0.5 6 ±0.5 0.4 +0.05 1 1.27 3.81 4 9 +0.75 -0.5 0.25 -0.15 Adhesive Tape Tape 6.35 ±0.4 12.7 ±0.3 4 ±0.3 0.5 ±0.1 GPO05357 d Branded Side Hall-Probe d : Distance chip to upper side of IC P-SSO-4-1 : 0.3 ±0.08 mm AEA02712 Sorts of Packing Package outlines for tubes, trays etc. are contained in our Data Book “Package Information”. Data Sheet 19 Dimensions in mm 2000-07-01