ATS692LSH(RSNBL) Two-Wire, Differential, Vibration Resistant Sensor IC with Speed and Direction Output Description Features and Benefits • Two-wire, pulse width output protocol • Digital output representing target profile • Speed and direction information of target • Vibration tolerance ▫ Small signal lockout for small amplitude vibration ▫ Proprietary vibration detection algorithms for large amplitude vibration • Air gap independent switch points • Large operating air gap capability • Undervoltage lockout • True zero-speed operation • Wide operating voltage range • Single chip sensing IC for high reliability • Robust test coverage capability with Scan Path and IDDQ measurement The ATS692LSH is an optimized Hall-effect integrated circuit (IC) and rare earth pellet combination that provides a userfriendly solution for direction detection and true zero-speed, digital gear tooth sensing. The small package can be easily assembled and used in conjunction with a wide variety of gear tooth sensing applications. The IC employs patented algorithms for the special operational requirements of automotive transmission applications. The speed and direction of the target are communicated through a variable pulse width output protocol. The ATS692 is particularly adept at handling vibration without sacrificing maximum air gap capability or creating any erroneous direction information. Even higher angular vibration caused by engine cranking is completely rejected by the device. The advanced vibration detection algorithm systematically calibrates the sensor IC on the initial teeth of true target rotation and not on vibration, always guaranteeing an accurate signal in running mode. Package: 4-pin SIP (suffix SH) Advanced signal processing and innovative algorithms make the ATS692 an ideal solution for a wide range of speed and direction sensing needs. This device is available in a lead (Pb) free 4-pin SIP package with a 100% matte tin plated leadframe. Not to scale Functional Block Diagram VCC Regulator (Analog) Multiplexed Test Signals TEST Regulator (Digital) Hall Amp Offset Adjust AGC Filter ADC Synchronous Digital Controller Hall Amp ATS692LSH2-DS, Rev. 2 Offset Adjust AGC Filter ADC GND Two-Wire, Differential, Vibration Resistant Sensor IC with Speed and Direction Output ATS692LSH(RSNBL) Selection Guide Part Number Packing* Direction Change Function Vibration Immunity (Running Mode) ATS692LSHTN-RSNBL-T 800 pieces per reel First edge direction 0.12 × TTARGET *Contact Allegro™ for additional packing options. Configuration ATS692LSHTN- -T 100% matte tin leadframe plating Vibration Immunity / Direction Change: L – Low vibration immunity, with immediate direction change detection Calibration Pulses: B – Blanked, no output during calibration Reverse Pulse Width: N – Narrow, 90 μs Number of Pulses: S – Single, one pulse per tooth / valley Rotation Direction: R – Reverse, target movement forward direction from pin 4 to 1 Allegro Identifier and Device Type: ATS692 Operating Temperature Range: L Package Designation: SH Instructions (Packing): TN – Tape and reel, 800 pieces per 13-in. reel Absolute Maximum Ratings Characteristic Symbol Supply Voltage VCC Reverse Supply Voltage VRCC Notes Refer to Power Derating section Rating Unit 28 V –18 V Operating Ambient Temperature TA –40 to 150 ºC Maximum Junction Temperature TJ(max) 165 ºC Tstg –65 to 170 ºC Storage Temperature Pin-out Diagram 1 2 3 4 L temperature range Terminal List Table Number Name Function 1 VCC Supply voltage 2 TEST Test pin: float * 3 TEST Test pin: float * 4 GND Ground *Connection of TEST to VCC and/or GND may cause undesired additional current consumption in the IC. Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 2 Two-Wire, Differential, Vibration Resistant Sensor IC with Speed and Direction Output ATS692LSH(RSNBL) OPERATING CHARACTERISTICS Valid at throughout full operating and temperature ranges; using Reference Target 60-0; unless otherwise specified Characteristic Symbol Test Conditions Min. Typ.1 Max. Unit 4.0 – 24 V General Electrical Characteristics Supply Voltage2 Under Voltage Lockout Reverse Supply Current3 Supply Zener Clamp Voltage Supply Current VCC Operating, TJ < TJ(max) VCC(UV) VCC 0 → 5 V or 5 → 0 V – 3.6 3.95 V VCC = VRCC(max) – – –10 mA IRCC VZ(SUPPLY) ICC = ICC(max) + 3 mA, TA = 25ºC 28 – – V ICC(LOW) Low-current state (Running mode) 5.0 – 8.0 mA ICC(HIGH) High-current state (Running mode) 12.0 – 16.0 mA 5.0 – 8.5 mA 1.9 – – – – 6 – V 7.0 16 – mA / μs ICC(SU)(LOW) Startup current level (Power-On mode) Supply Current Ratio Test Pins Zener Clamp Voltage4 ICC(HIGH) / ICC(LOW) Measured as ratio of high current to low current VZ(TEST) Output Stage Output Slew Rate SROUT RL = 100 Ω, CL = 10 pF; ICC(HIGH) → ICC(LOW) , ICC(LOW) → ICC(HIGH) , 10% to 90% points Output Pulse Characteristics5 Pulse Width (Forward Rotation) tw(FWD) 38 45 52 μs Pulse Width (Reverse Rotation) tw(REV) 76 90 104 μs General Operating Characteristics Operate Point BOP % of peak-to-peak VPROC – 69 – % Release Point BRP % of peak-to-peak VPROC – 31 – % Operating Frequency (Forward Rotation) fFWD 0 – 12 kHz Operating Frequency (Reverse Rotation)6 fREV 0 – 7 kHz Magnitude valid for both differential magnetic channels –60 – 60 G Using Allegro Reference Target 60-0 0.5 – 2.75 mm DAC Characteristics Allowable User-Induced Offset BOFFSET Performance Characteristics Air Gap Range Vibration Immunity (Startup) Vibration Immunity (Running Mode) AG errVIB(SU) See figure 1 1.0 × TTARGET – – deg. errVIB See figure 1 0.12 × TTARGET – – deg. Continued on the next page… Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 3 Two-Wire, Differential, Vibration Resistant Sensor IC with Speed and Direction Output ATS692LSH(RSNBL) OPERATING CHARACTERISTICS (continued) Valid at throughout full operating and temperature ranges; using Reference Target 60-0; unless otherwise specified Characteristic Symbol Min. Typ.1 Max. Unit AG ≥ 0.5 mm AG < 2.25 mm – 2× TTARGET <3 × TTARGET deg. AG ≥ 2.25 mm AG ≤ 2.75 mm – 2.5 × TTARGET <4 × TTARGET deg. – 1 – switch– point – – 1.25 × TTARGET deg. Test Conditions Calibration Amount of target rotation (constant direction) following power-on until first electrical output pulse of either tw(FWD) or tw(REV) , see figure 1 First Direction Output Pulse7 First Direction Pulse Output Following Direction Change NCD Amount of target rotation (constant direction) following event until first electrical output pulse of either tw(FWD) or tw(REV) , see figure 1 First Direction Pulse Output Following Running Mode Vibration 1Typical values are at TA = 25°C and VCC = 12 V. Performance may vary for individual units, within the specified maximum and minimum limits. voltage must be adjusted for power dissipation and junction temperature; see Power Derating section. 3Negative current is defined as conventional current coming out of (sourced from) the specified device terminal. 4Sustained voltages beyond the clamp voltage may cause permanent damage to the IC. 5Load circuit is R = 100 Ω and C = 10 pF. Pulse duration measured at a threshold of (I L L CC(HIGH) + ICC(LOW)) / 2. 6Maximum of Operating Frequency (Reverse Rotation) is determined by satisfactory separation of output pulses: I CC(LOW) of tw(FWD)(min). If the customer can resolve lower low-state durations, maximum fREV may be increased. 7Power-on frequency ≤ 200 Hz. Higher power-on frequencies may require more input magnetic cycles until output edges are achieved. 2Maximum Target Valley Tooth TTARGET TVPROC VPROC VPROC = the processed analog signal of the sinusoidal magnetic input (per channel) TTARGET = period between successive sensed target mechanical edges of the same orientation (either both rising or both falling) Figure 1. Definition of TTARGET Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 4 Two-Wire, Differential, Vibration Resistant Sensor IC with Speed and Direction Output ATS692LSH(RSNBL) Thermal Characteristics may require derating at maximum conditions, see Power Derating section Characteristic Symbol Test Conditions* Single layer PCB, with copper limited to solder pads RθJA Package Thermal Resistance Single layer PCB, with copper limited to solder pads and 3.57 (23.03 cm2) copper area each side in.2 Value Unit 126 ºC/W 84 ºC/W *Additional thermal information available on the Allegro website Maximum Allowable VCC (V) Power Derating Curve 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 VCC(max) (R θJA = 84 °C/W) (R θJA = 126 °C/W) VCC(min) 20 40 60 80 100 120 140 160 180 Temperature (°C) Power Dissipation, PD (m W) Power Dissipation versus Ambient Temperature 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 20 RQJA = 84 ºC/W RQJA = 126 ºC/W 40 60 80 100 120 140 Temperature,TA (°C) 160 180 Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 5 Two-Wire, Differential, Vibration Resistant Sensor IC with Speed and Direction Output ATS692LSH(RSNBL) Reference Target 60-0 (60 Tooth Target) Characteristics Symbol Test Conditions Typ. Units 120 mm Outside Diameter Do Outside diameter of target Face Width F Breadth of tooth, with respect to branded face 6 mm Angular Tooth Thickness t Length of tooth, with respect to branded face 3 deg. Angular Valley Thickness tv Length of valley, with respect to branded face 3 deg. Tooth Whole Depth ht 3 mm – – Material Low Carbon Steel Symbol Key t Do ht F tv Air Gap Branded Face of Sensor Reference Gear Magnetic Gradient Amplitude versus Air Gap Reference Target 60-0 800 600 500 400 300 Branded Face of Sensor 200 100 0 0.5 1.0 1.5 2.0 2.5 Reference Target 60-0 3.0 Air Gap (mm) Reference Gear Magnetic Profile Two Tooth-to-Valley Transitions 500 Air Gap 400 (mm) 0.50 0.75 1.00 1.25 1.50 1.75 2.00 2.25 2.50 2.75 3.00 300 Differential B* (G) Peak-to-Peak Differential B (G) 700 200 100 0 -100 -200 3.00 mm AG -300 0.50 mm AG -400 -500 0 2 4 6 8 10 12 Gear Rotation (°) Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 6 Two-Wire, Differential, Vibration Resistant Sensor IC with Speed and Direction Output ATS692LSH(RSNBL) Functional Description Sensing Technology The sensor IC contains a single-chip Hall-effect circuit that supports a trio of Hall elements. These elements are used in differential pairs to provide electrical signals containing information regarding edge position and direction of target rotation. The ATS692 is intended for use with ferromagnetic targets. After proper power is applied to the sensor IC, it is capable of providing digital information that is representative of the magnetic features of a rotating target. The waveform diagrams in figure 3 present the automatic translation of the target profiles, through their induced magnetic profiles, to the digital output signal of the sensor IC. Direction Detection The sensor IC compares the relative phase of its two differential channels to determine in which direction the target is moving. The relative switching order is used to determine the direction, which is communicated through the output protocol. Data Protocol Description When a target passes in front of the device (opposite the branded face of the package case), the ATS692 generates an output pulse for each tooth of the target. Speed information is provided by the output pulse rate, while direction of target rotation is provided by the duration of the output pulses. The sensor IC can sense target movement in both the forward and reverse directions. Pin 4 Pin 1 Forward Rotation (see panel A in figure 2) When the target is rotating such that a tooth near the sensor IC passes from pin 4 to pin 1, this is referred to as forward rotation. Forward rotation is indicated on the output by a tw(FWD) (45 μs typical) pulse width. Reverse Rotation (see panel B in figure 2) When the target is rotating such that a tooth passes from pin 1 to pin 4, it is referred to as reverse rotation. Reverse rotation is indicated on the output by pulse widths of tw(REV) (90 μs typical). Target Package Case Branded Face Device Orientation to Target (Top View of (Pin 4 Package Case) Side) Back-Biasing Rare-Earth Pellet B Channel E3 IC ICE2 E1 (Pin 1 Side) South Pole Pole Piece (Concentrator) A Channel North Pole Mechanical Position (Target moves past device pin 1 to pin 4) This tooth sensed later This tooth sensed earlier Target Magnetic Profile +B IC Internal Differential Analog Signals, VPROC BOP A Channel Branded Face of Package Rotating Target (Ferromagnetic) BRP B Channel BRP (A) Forward Rotation Pin 4 BOP Detected Channel Switching Pin 1 A Channel B Channel Device Output Signal Rotating Target (Ferromagnetic) Branded Face of Package ICC(High) ICC(Low) (B) Reverse Rotation Figure 2. Target rotation Figure 3. The magnetic profile reflects the features of the target, allowing the sensor IC to present an accurate digital output. Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 7 ATS692LSH(RSNBL) Two-Wire, Differential, Vibration Resistant Sensor IC with Speed and Direction Output Timing As shown in figure 4, the pulse appears at the output slightly before the sensed magnetic edge traverses the package branded face. For targets in forward rotation, this shift, Δfwd, results in the pulse corresponding to the valley with the sensed mechanical edge, and for targets in reverse rotation, the shift, Δrev, results in the pulse corresponding to the tooth with the sensed edge. The sensed mechanical edge that stimulates output pulses is kept the same for both forward and reverse rotation by using only one channel to control output switching. Direction Validation Following a direction change in running mode, direction changes are immediately transmitted to the output. An example of the waveforms is shown in figure 5. Forward Rotation Reverse Rotation Valley Tooth ∆fwd tw(FWD) 45 μs Output Pulse (Forward Rotation) t ∆rev tw(REV) 90 μs Output Pulse (Reverse Rotation) t Figure 4. Output protocol Target Rotation Forward Valley Target Rotation Reverse Tooth Target Differential Magnetic Profile IOUT tW(FWD) tW(FWD) tW(REV) tW(REV) t Figure 5. Example of direction change in Running mode Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 8 Two-Wire, Differential, Vibration Resistant Sensor IC with Speed and Direction Output ATS692LSH(RSNBL) Start-Up Detection / Calibration When power is applied to the ATS692, the sensor IC internally detects the profile of the target. The gain and offset of the detected signals are adjusted during the calibration period, normalizing the internal signal amplitude for the air gap range of the device. The Automatic Gain Control (AGC) feature ensures that operational characteristics are isolated from the effects of installation air gap variation. Automatic Offset Adjustment (AOA) is circuitry that compensates for the effects of chip, magnet, and installation offsets. This circuitry works with the AGC during calibration to adjust VPROC in the internal A-to-D range to allow for acquisition of signal peaks. AOA and AGC function separately on the two differential signal channels. Direction information is available after calibration is complete. The output becomes active at the end of calibration. Figure 6 shows where the first output edges may occur for various starting target phases. Vibration Detection Algorithms embedded in the IC digital controller detect the presence of target vibration through analysis of the two magnetic input channels. The first direction change is immediately transmitted to the output. During any subsequent vibration, the output is blanked and no output pulses occur for vibrations less than the specified vibration immunity (see figure 7). When constant rotation resumes, output pulses containing the proper direction information will resume when direction information is validated on constant target rotation. Target Rotation Valley Tooth Target Differential Magnetic Profile ICC Opposite valley Opposite rising edge tW(FWD) or tW(REV) tW(FWD) or tW(REV) tW(FWD) or tW(REV) tW(FWD) or tW(REV) tW(FWD) or tW(REV) tW(FWD) or tW(REV) tW(FWD) or tW(REV) Opposite tooth Opposite falling edge t Device Location at Power-On Figure 6. Start-up position effect on first device output switching t Normal Target Rotation Valley Vibration Normal Target Rotation Tooth Target Differential Magnetic Profile tW(FWD) tW(FWD) [ or tW(REV) ] [ or tW(REV) ] tW(REV) [ or tW(FWD) ] tW(FWD) tW(FWD) [ or tW(REV) ] [ or tW(REV) ] t Figure 7. Output functionality in the presence of Running mode target vibration Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 9 ATS692LSH(RSNBL) Two-Wire, Differential, Vibration Resistant Sensor IC with Speed and Direction Output Application Information Power Derating The device must be operated below the maximum junction temperature of the device, TJ(max). Under certain combinations of peak conditions, reliable operation may require derating supplied power or improving the heat dissipation properties of the application. This section presents a procedure for correlating factors affecting operating TJ. (Thermal data is also available on the Allegro website.) The Package Thermal Resistance, RJA, is a figure of merit summarizing the ability of the application and the device to dissipate heat from the junction (die), through all paths to the ambient air. Its primary component is the Effective Thermal Conductivity, K, of the printed circuit board, including adjacent devices and traces. Radiation from the die through the device case, RJC, is relatively small component of RJA. Ambient air temperature, TA, and air motion are significant external factors, damped by overmolding. The effect of varying power levels (Power Dissipation, PD), can be estimated. The following formulas represent the fundamental relationships used to estimate TJ, at PD. PD = VIN × IIN (1) T = PD × RJA (2) TJ = TA + ΔT (3) For example, given common conditions such as: TA= 25°C, VCC = 12 V, ICC = 6.5 mA, and RJA = 126 °C/W, then: Example: Reliability for VCC at TA = 150°C, package SH, using a single-layer PCB. Observe the worst-case ratings for the device, specifically: RJA = 126 °C/W, TJ(max) = 165°C, VCC(max) = 24 V, and ICC(mean) = 13 mA. (Note: At maximum target frequency, ICC(LOW) = 8 mA, ICC(HIGH) = 16 mA, and maximum pulse widths, the result is a duty cycle of 62.4% and a worst case ICC(mean) of 13 mA.) Calculate the maximum allowable power level, PD(max). First, invert equation 3: Tmax = TJ(max) – TA = 165 °C – 150 °C = 15 °C This provides the allowable increase to TJ resulting from internal power dissipation. Then, invert equation 2: PD(max) = Tmax ÷ RJA = 15°C ÷ 126 °C/W = 119 mW Finally, invert equation 1 with respect to voltage: VCC(est) = PD(max) ÷ ICC(max) = 119 mW ÷ 13 mA = 9.2 V The result indicates that, at TA, the application and device can dissipate adequate amounts of heat at voltages ≤ VCC(est). Compare VCC(est) to VCC(max). If VCC(est) ≤ VCC(max), then reliable operation between VCC(est) and VCC(max) requires enhanced RJA. If VCC(est) ≥ VCC(max), then operation between VCC(est) and VCC(max) is reliable under these conditions. PD = VCC × ICC = 12 V × 6.5 mA = 78 mW V CC T = PD × RJA = 78 mW × 126 °C/W = 9.8°C TJ = TA + T = 25°C + 9.8°C = 34.8°C A worst-case estimate, PD(max), represents the maximum allowable power level (VCC(max), ICC(max)), without exceeding TJ(max), at a selected RJA and TA. 1 VCC ATS692 TEST 3 2 TEST 0.01 MF CBYPASS GND 4 RL 100 7 CL Figure 8. Typical application circuit Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 10 Two-Wire, Differential, Vibration Resistant Sensor IC with Speed and Direction Output ATS692LSH(RSNBL) Package SH, 4-Pin SIP F 5.50±0.05 1.75 E 1.75 F B 8.00±0.05 LLLLLLL NNN 5.80±0.05 E3 E1 E2 YYWW Branded Face 1.70±0.10 5.00±0.10 D 4.00±0.10 1 2 3 4 = Supplier emblem L = Lot identifier N = Last three numbers of device part number Y = Last two digits of year of manufacture W = Week of manufacture A 0.60±0.10 Standard Branding Reference View 0.71±0.05 For Reference Only, not for tooling use (reference DWG-9003) Dimensions in millimeters A Dambar removal protrusion (16X) 24.65±0.10 B Metallic protrusion, electrically connected to pin 4 and substrate (both sides) C Thermoplastic Molded Lead Bar for alignment during shipment +0.06 0.38 –0.04 1.00±0.10 13.10±0.10 D Branding scale and appearance at supplier discretion E Active Area Depth 0.43 mm REF F Hall elements (E1, E2, E3); not to scale A 1.0 REF 1.60±0.10 C 1.27±0.10 0.71±0.10 0.71±0.10 5.50±0.10 Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 11 Two-Wire, Differential, Vibration Resistant Sensor IC with Speed and Direction Output ATS692LSH(RSNBL) Revision History Revision Rev. 2 Revision Date August 27, 2013 Description of Revision Upgrades to select graphics, Tstg, errVIB and errVIB(SU) update Copyright ©2010-2013, Allegro MicroSystems, LLC Allegro MicroSystems, LLC reserves the right to make, from time to time, such departures from the detail specifications as may be required to permit improvements in the performance, reliability, or manufacturability of its products. Before placing an order, the user is cautioned to verify that the information being relied upon is current. Allegro’s products are not to be used in life support devices or systems, if a failure of an Allegro product 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. The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, LLC assumes no responsibility for its use; nor for any infringement of patents or other rights of third parties which may result from its use. For the latest version of this document, visit our website: www.allegromicro.com Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 12