ATS645LSH Preliminary – Subject to Change True Zero Speed Miniature Gear Tooth Sensor PRELIMINARY DATASHEET (subject to change without notice) The ATS645LSH is an optimized Hall effect sensing integrated circuit and magnet combination that provides a user-friendly solution for true zero-speed digital gear-tooth sensing in two-wire applications. The sensor consists of a single-shot molded plastic package that includes a samarium cobalt magnet, a pole piece, and a Hall effect IC that has been optimized to the magnetic circuit. This small package can be easily assembled and used in conjunction with a wide variety of gear shapes and sizes. The integrated circuit incorporates a dual element Hall effect sensor and signal processing that switches in response to differential magnetic signals created by ferrous gear teeth. The circuitry contains a sophisticated digital circuit to eliminate magnet and system offsets and to achieve true zero speed operation (ref U.S. Patent 5,917,320). A-D and D-A converters are used to adjust the device gain at power up and to allow air gap independent switching. Pin 1: Supply Pin 2: No connection Pin 3: Test pin Pin 4: Ground ABSOLUTE MAXIMUM RATINGS Supply Voltage, VCC . . . . . . . . . . . . . . . . . . . . . . . . . 26.5 V* Reverse Supply Voltage, VR . . . . . . . . . . . . . . . . . . . . . . . . . . . . –18 V Operating Temperature Range, TA . . . . . . . . . . . . . . . . . –40 °C to 150 °C* Storage Temperature, TS . . . . . . . . . . . . . . . . . . . . . . . . . . . 170 °C Package Power Rating, ϑ JA . . . . . . . . . . . . . . . . . . . . . . . . 126 °C/W Maximum Junction Temperature, TJmax . . . . . . . . . . . . . . . . . . . . . 165 °C * Operation at increased supply voltages with external circuitry is described in the Applications Information. ATS645LSH-DS Rev. 1 The regulated current output is configured for two wire applications and the sensor is ideally suited for obtaining speed and duty cycle in ABS and transmission application gear-tooth-based configurations. FEATURES s s s s s s s s s s s s s s Fully optimized differential digital gear tooth sensor Single chip sensing IC for high reliability Internal current regulator for 2 wire operation Small mechanical size (8 mm dia x 5.5 mm length) Air gap independent switch points Digital output representing gear profile Precise duty cycle signal with temperature Large operating air gaps Automatic Gain Control (AGC) Automatic Offset Adjustment circuit True zero speed operation Under-voltage lockout Wide operating voltage range Defined power-on state ATS645LSH – Preliminary – Allegro Confidential TRUE ZERO SPEED DIFFERENTIAL PEAK DETECTOR CHARACTERISTICS Valid over operating temperature range and Supply Voltage within specification unless otherwise noted. Characteristics Symbol Limits Test Conditions Min. Typ. Max. Units 24 V ELECTRICAL CHARACTERISTICS Supply Voltage VCC Operating, TJ < 165°C 4.0 VCC(UV) VCC 0 → 5 V - - <Vcc Min V VZ IZT = 1 mA 28 32 - V Max Zener Pulse Current IZ t=20mS Pulse Mode - - 50 mA Supply Zener Resistance RZ - 50 - Ω Supply Current ATS645LSH – I1 ICC Low Current State: IccLow 4.0 6 8.0 mA High Current State: IccHigh 12.0 14.0 16.0 mA Supply Current ATS645LSH – I2 ICC Low Current State: IccLow 5.9 7 8.4 mA High Current State: IccHigh 11.8 14.0 16.8 mA SPO VCC 0 → 5 V - IccHigh - - ton Gear speed < 100 rpm - 1 2 ms IR IccHigh à IccLow, IccLow à IccHigh, RS = 100 Ω, CS = 10 pF, 10 to 90% Under Voltage Lockout 1 Supply Zener Clamp Voltage POWER-ON STATE CHARACTERISTICS Power-On State 2 Power-On Time OUTPUT STAGE Output Current Slew Rate 10 1 mA/µs The zener is tested using a pulse method and is designed for transient protection, continuous operation may destroy the device. Power On Time is the time required to complete internal offset adjust. It does not include automatic gain control, which requires three tooth valley transitions to complete and is therefore RPM dependent. 2 Revision 1.2; MHN; 07.Aug.02 Page 2 of 12 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1993, 1995 Allegro MicroSystems, Inc. ATS645LSH – Preliminary – Allegro Confidential TRUE ZERO SPEED DIFFERENTIAL PEAK DETECTOR Operating Characteristics: Valid with Reference Target unless otherwise specified Characteristics Symbol Limits Test Conditions Min. Typ. Max. Units 8K RPM SWITCH POINT CHARACTERISTICS Rotation Speed Smax Using Reference Target over Operating Air Gap Range 0 Analog Signal Bandwidth f-3db -3dB Point 20 40 1 Bop - 100 150 mV 1 Brp - 100 150 mV 3 Edges 60 G Operate Point Release Point IccHigh à IccLow Positive Peak referenced, AG < AGmax IccLow à IccHigh Negative Peak referenced, AG < AGmax KHz Calibration Initial Calibration CI Number of Rising Mechanical Edges for Accurate Edge Detection DAC Characteristics Output switching only; may not meet data sheet specifications Allowable User Induced Differential Offset -60 SWITCH POINT DETAIL Bop Input Differential Signal Brp Device Output Current Pin 3 Differential Signal (not magnetic signal) 1 Bop and Brp should be adjustable with metal mask changes, limits max air gap but improves vibration immunity. Revision 1.2; MHN; 07.Aug.02 Page 3 of 12 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1993, 1995 Allegro MicroSystems, Inc. ATS645LSH – Preliminary – Allegro Confidential TRUE ZERO SPEED DIFFERENTIAL PEAK DETECTOR Operating Characteristics: Valid only if magnetic offset is within the Dynamic Offset Compensation DAC Range as specified above Characteristics Symbol Limits Test Conditions Min. Typ. Max. Units OPERATING CHARACTERISTICS: Using Reference Target and Valid Over Operating Temperature Range 1 Operational Air Gap Range Switching Air Gap Range OpAG OpMaxAG Duty Cycle Variation DC 2 Sig 3 SigMin Operating Signal Range Minimum Operating Signal Duty cycle within specification Output Switching: Duty cycle Not in Specification Wobble < 0.5mm Typical value at 1.5mm air gap Valid over operating air gap range Duty cycle within Specification Wobble < 0.5mm Output Switching: Duty Cycle Not in Specification 0.5 2.75 mm 3 - - mm 37 53 57 % 30 - 1000 G 20 - - G 1 Operating air gap is dependent on the available magnetic field. The available field is target geometry and materiel dependent and should be independently characterized. The field available from the reference target is given in the reference gear parameter section of the datasheet 2 In order to remain in specification the magnetic signal must be larger than the minimum value specified, this includes the effect of target wobble. 3 Duty cycle is not guaranteed to be in specification. Reference the Duty Cycle vs. Air Gap Over Temperature graph in the typical operating characteristics section of this document. Revision 1.2; MHN; 07.Aug.02 Page 4 of 12 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1993, 1995 Allegro MicroSystems, Inc. ATS645LSH – Preliminary – Allegro Confidential TRUE ZERO SPEED DIFFERENTIAL PEAK DETECTOR Reference Gear Parameters REFERENCE GEAR DIMENSIONS (60-0) Diameter Gd - 120 - mm Thickness Gt - 6 - mm Tooth Width Tw - 3 - mm Valley Width Vw - 3 - mm Valley Depth Vd - 3 - mm Materiel Low Carbon Steel Target Description: Tooth Width: 3.25mm Diameter: 120mm Valley Width: 3.10mm Tooth Thickness: 6mm Valley Depth: 3mm Flux Density vs. Position Reference Target 300 250 200 Flux Density (Gauss) 150 100 50 0.94mm 1.19mm 1.44mm 1.69mm 1.94mm 2.19mm 2.44mm 2.69mm 2.94mm 3.19mm 3.44mm 3.69mm 0 -50 -100 -150 -200 -250 -300 244 246 248 250 252 254 Position (º) 256 258 260 262 Reference Target Peak to Peak vs. Air Gap 500 450 400 P-P [Gauss] 350 300 250 200 150 100 50 0 0.75 Revision 1.2; MHN; 07.Aug.02 Page 5 of 12 1 1.25 1.5 1.75 2 2.25 2.5 Air Gap [mm] 2.75 3 3.25 3.5 3.75 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1993, 1995 Allegro MicroSystems, Inc. ATS645LSH – Preliminary – Allegro Confidential TRUE ZERO SPEED DIFFERENTIAL PEAK DETECTOR Typical Operating Characteristics: Duty Cycle vs. Air Gap Over Temperature Duty Cycle vs. Air Gap Allegro MicroSystems, Inc. Standard Production 60-0 Target ATS645LSH @ 1000RPM 65 Typical @ 25ºC Typical @ 150ºC Typical @ -40ºC Duty Cycle (%) 60 55 50 45 40 35 0.5 0.75 1 1.25 1.5 1.75 2 2.25 2.5 2.75 3 3.25 Air Gap (mm) Figure #1: Duty Cycle vs. Air Gap Over Temperature with Reference Target and Orientation Given in Figure #2 ROTATION RIGHT is CW from pin 4 to pin 1 Figure #2: Sensor Orientation and Direction of Rotation of Reference Target for Duty Cycle Graph in Figure #1 Revision 1.2; MHN; 07.Aug.02 Page 6 of 12 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1993, 1995 Allegro MicroSystems, Inc. ATS645LSH – Preliminary – Allegro Confidential TRUE ZERO SPEED DIFFERENTIAL PEAK DETECTOR SENSOR DESCRIPTION Assembly Description: The ATS645LSH true zero speed gear tooth sensor is a Hall IC/magnet configuration that is fully optimized to provide digital detection of gear tooth edges. This sensor is integrally molded into a plastic body that has been optimized for size, ease of assembly, and manufacturability. High operating temperature materials are used in all aspects of construction. Sensing Technology: The gear tooth sensor sub-assembly contains a single-chip differential Hall effect sensor IC, a Samarium Cobalt magnet, and a flat ferrous pole piece. The Hall IC consists of 2 Hall elements spaced 1.5 mm apart that measure the magnetic gradient created by the passing of a ferrous object. The two elements measure the magnetic gradient and convert it to an analog voltage that is then processed to provide a digital output signal. Revision 1.2; MHN; 07.Aug.02 Page 7 of 12 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1993, 1995 Allegro MicroSystems, Inc. ATS645LSH – Preliminary – Allegro Confidential TRUE ZERO SPEED DIFFERENTIAL PEAK DETECTOR Transient Performance per ISO 7637-1 at TA = 23 ±5°C (Tested at Allegro test facility – for engineering reference only) Pulse No. Test I 1 2 3a 3b 4 5 6 7 Inductive turn off (negative) Inductive turn off (positive) Capacitive/inductive coupling (neg) Capacitive/inductive coupling (pos) Reverse battery Load dumb Ignition coil disconnect Field decay (negative) A - Performance Class at Test Level II III C - C C - IV C A A A A E E C UA = 13.5V for pulses 1, 2, 3a, 3b, 5, 6, 7 and 12V for pulse 4. Test Circuit #1 Performance Class Definitions PCB Ouline by Dashed Line (for transient performance and EMC performance) Icc A – All functions of a device perform as designed during and after the exposure. Pin #1 Pin #2 VEMC 645 Pin #3 0.01uF Pin #4 100Ohm Pins #2 and #3 Floating ECU Transient & EMC test circuit Power supply voltage transients, or device output short circuits, may be caused by faulty connectors, crimped wiring harnesses, or service errors. The prevent catastrophic failure, internal protection against over-voltage, reverse voltage, and output overloads have been incorporated to meet the automotive 12 volt system protection requirements of ISO DP7637/1. A series-blocking diode or current-limiting resistor is required in order to survive pulse number six. Revision 1.2; MHN; 07.Aug.02 Page 8 of 12 B – All functions of a device perform as designed during exposure; however, one or more of them may go beyond the specified limit tolerance. All functions return automatically to within normal limits after exposure is removed. Memory must remain Class A. C – One or more functions of the device do not perform as designed during exposure but return automatically to normal operation after exposure is removed. D – One or more functions of the device do not perform as designed during exposure and do not return to normal operation until exposure is removed and the device is reset by simple “ operator” action. E – One or more functions of the device do not perform as designed during and after the exposure and cannot be returned to proper operation without repairing or replacing the device. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1993, 1995 Allegro MicroSystems, Inc. ATS645LSH – Preliminary – Allegro Confidential TRUE ZERO SPEED DIFFERENTIAL PEAK DETECTOR ELECTROMAGNETIC COMPATIBILITY (EMC) PERFORMANCE at TA = 23 ±5°C (Tested at Allegro test facility – for engineering reference only) TEM Cell Performance per ISO 11452-3 Test severity level I = 50 V/m II = 100 V/m III = 150 V/m IV = 200 V/m Frequency Band (MHz) F1 (0.01 to 10) F2 (0 to 30) F3 (30 to 80) F4 (80 to 200) Performance Class at Test Level II III I – – – – – – – – – – A B IV A A A B BCI per ISO 11452-4 Test severity level I = 25 mA II = 50 mA III = 75 mA IV = 100 mA Frequency Band (MHz) F1 (1 to 10) F2 (10 to 30) F3 (30 to 80) F4 (80 to 200) F5 (200 to 400) Performance Class at Test Level II III I – – – – – – – – – – – – – – – IV A A A A A Direct RF per ISO 11452-7 Test severity level I = 100 mW II = 200 mW III = 300 mW IV = 400 mW V = 500 mW Frequency Band (MHz) F1 (1 to 10) F2 (10 to 30) F3 (30 to 80) F4 (80 to 200) F5 (200 to 400) Revision 1.2; MHN; 07.Aug.02 Page 9 of 12 I II Performance Class at Test Level III IV V 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1993, 1995 Allegro MicroSystems, Inc. ATS645LSH – Preliminary – Allegro Confidential TRUE ZERO SPEED DIFFERENTIAL PEAK DETECTOR MECHANICAL INFORMATION 1 2 Component Material Function Value Sensor Package Material Thermoset Epoxy Max. Temperature 170°C Leads Copper, 0.016” dia, 0.050” spacing Lead Coating Solder, Tin / Lead 90/10 1 2 Temperature excursions of up to 225°C for 2 minutes or less are permitted. Industry accepted soldering techniques are acceptable for this sub-assembly as long as the indicated maximum temperatures for each component are not exceeded. DEVICE QUALIFICATION PROGRAM Test Name High Temperature Operating Life Test Conditions AEC-Q100 #2 (JA108) Ta = 150°C, Tj = 165°C AEC-Q100 #3 (JA103) High Temperature Bake Ta = 170°C Temperature Humidity AEC-Q100 #5 (JA101) Bias 85°C/85%RH Autoclave AEC-Q100 #6 (JA102) Test Length # of Lots Sample / lot 408 hrs 1 77 1000 hrs 1 77 1008 hrs 1 77 96 hrs 1 77 500 cycles 1 Temperature Cycling AEC-Q100 #7(JA104) ESD AEC-Q100 #20 (AEC-Q100002, AEC-Q100-003) - 1 Early Life Failure Rate AEC-Q100 #25 (AEC-Q100008) 150°C/24 hrs 1 Revision 1.2; MHN; 07.Aug.02 Page 10 of 12 Comments -65°C to +160°C, 30 sec. transition, 30 minute dwell Passes ±6kV all pin 3/model/step combinations: Human Body Model 77 800 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1993, 1995 Allegro MicroSystems, Inc. ATS645LSH – Preliminary – Allegro Confidential TRUE ZERO SPEED DIFFERENTIAL PEAK DETECTOR Functional block diagram Vcc/Output Hall AMP + AGC INTERNAL REGURATOR Auto Offset Control Offset DAC Track DAC AGC DAC Peak Hold V Neg Test Pin Test signals Typical Application Circuit PCB Ouline by Dashed Line Icc Pin #1 Pin #2 Pin #3 VSupply 645 0.01uF Pins #2 and #3 Floating Revision 1.2; MHN; 07.Aug.02 Page 11 of 12 ECU 100Ohm Pin #4 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1993, 1995 Allegro MicroSystems, Inc. ATS645LSH – Preliminary – Allegro Confidential TRUE ZERO SPEED DIFFERENTIAL PEAK DETECTOR SENSOR PACKAGE LSH PACKAGE REFERENCE DIMENSIONS ONLY Revision 1.2; MHN; 07.Aug.02 Page 12 of 12 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1993, 1995 Allegro MicroSystems, Inc.