ATS675LSETN-HT-T

ATS675LSE ALLEGRO | Alldatasheet

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Description

The ATS675 is the next generation of the Allegro ® True Power-On State (TPOS) sensor family, offering improved accuracy compared to prior generations, gradual TPOS to Running Mode adjustment for accuracy-shift reduction, and longer output fall time for improved radiated emissions performance. The ATS675 provides absolute zero-speed performance and TPOS information. The sensor incorporates a single-element Hall IC with an optimized custom magnetic circuit that switches in response to magnetic signals created by a ferromagnetic target. The IC contains a sophisticated digital circuit designed to eliminate the detrimental effects of magnet and system offsets. Signal processing is used to provide device performance at zero target speed, independent of air gap, and which adapts dynamically to the typical operating conditions found in automotive applications, particularly camshaft-sensing applications. High resolution peak-detecting DACs are used to set the adaptive switching thresholds of the device, ensuring high accuracy despite target eccentricity. Internal hysteresis in the thresholds reduces the negative effects of anomalies in the magnetic signal (such as magnetic overshoot) associated with targets used in many automotive applications. The resulting output of the device is a digital representation of the ferromagnetic target profile. The ATS675 also includes a low bandwidth filter that increases the noise immunity and the signal-to-noise ratio of the sensor. The device package is lead (Pb) free, with 100% matte tin leadframe plating. ATS675LSE-DS Features and Benefits ▪ Chopper stabilized; optimized for automotive cam sensing applications ▪ Optimized absolute timing accuracy step size through gradual transition from TPOS to Running Mode ▪ High immunity to signal anomalies resulting from magnetic overshoot and peak-to-peak field variation ▪ Tight timing accuracy over full operating temperature range ▪ True zero-speed operation ▪ Automatic Gain Control circuitry for air gap independent switchpoints ▪ Operation at supply voltages down to 3.3 V ▪ Digital output representing target profile ▪ Undervoltage lockout (UVLO) ▪ Patented Hall IC-magnet system ▪ Increased output fall time for improved radiated emissions performance Self-Calibrating TPOS Speed Sensor Optimized for Automotive Cam Sensing Applications Package: 4-pin SIP module (suffix SE) Typical Application Not to scale ATS675LSE Figure 1. Operational circuit for the ATS675

3 Sensor

Self-Calibrating TPOS Speed Sensor Optimized for Automotive Cam Sensing ApplicationsATS675LSE 2Allegro MicroSystems, Inc.

115 Northeast Cutoff

Worcester, Massachusetts 01615-0036 U.S.A. Selection Guide Part Number Output Protocol Packing* ATS675LSETN-LT-T Output low opposite target tooth 13-in. reel, 450 pieces per reelATS675LSETN-HT-T Output high opposite target tooth *Contact Allegro for additional packing options Absolute Maximum Ratings Characteristic Symbol Notes Rating Units Supply Voltage V CC 28 V Reverse Supply Voltage V RCC –18 V Reverse Supply Current I RCC –50 mA Output Current I OUT(sink) Internal current limiting is intended to protect the device from output short circuits, but is not intended for continuous operation. 20 mA Operating Ambient Temperature T A Range L –40 to 150 ºC Maximum Junction Temperature T J(max) 165 ºC Storage Temperature T stg –65 to 170 ºC Thermal Characteristics may require derating at maximum conditions, see application information Characteristic Symbol Test Conditions* Value Units Package Thermal Resistance RθJA 1-layer PCB with copper limited to solder pads 101 ºC/W 2-layer PCB with copper limited to solder pads and 3.57 in.2 of copper area each side 77 ºC/W *Additional thermal information available on the Allegro website 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 20 40 60 80 100 120 140 160 180 Temperature, T A (°C) Power Dissipation, PD (mW) QJA = 1 01 º C/W) QJA = 7 7 º C/W) 20 40 60 80 100 120 140 160 180 Temperature, TA (ºC) Maximum Allowable VCC (V) (RQJA = 101 ºC/W) (RQJA = 77 ºC/W) VCC(max) VCC(min) Power Dissipation versus Ambient TemperaturePower Derating Curve

Self-Calibrating TPOS Speed Sensor Optimized for Automotive Cam Sensing ApplicationsATS675LSE 3Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 U.S.A. +/ – +/ – Temperature Compensation Trim Low Pass Filter Hall Amp Oscillator Internal Regulator (Analog) Internal Regulator (Digital) VCC Current Limit OUT GND Mode Control Baseline Trim Multiplexed Test Signals TEST TPOS Trim DDA PDAC NDAC Auto Gain Adjust Update Logic Running Mode Threshold Selector TPOS Dynamic Threshold DAC Functional Block Diagram Pin-out Diagram Terminal List Number Name Function

1 VCC Supply voltage

2 OUT Open drain output

3 TEST Test pin; connection to GND recommended

4 GND Ground

Continued on the next page… Self-Calibrating TPOS Speed Sensor Optimized for Automotive Cam Sensing ApplicationsATS675LSE 4Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 U.S.A. OPERATING CHARACTERISTICS Valid using reference target 8X, TA,TJ, and VCC within specification, unless otherwise noted Characteristics Symbol Test Conditions Min. Typ. 1 Max. Unit

Electrical Characteristics

Supply Voltage2 VCC Operating, TJ < TJ(max) 3.3 – 24 V Undervoltage Lockout V CCUV VCC = 0 → 5 V or 5 → 0 V – – 3.3 V Supply Zener Clamp Voltage V Zsupply ICC = ICC(max) + 3 mA, TA = 25°C 28 33 40 V Supply Zener Current3 IZsupply VS = 28 V – – 13 mA Supply Current I CC – 6.5 10 mA Reverse Battery Current4 IRCC VRCC = –18 V – –5 –10 mA Chopping Frequency f c – 500 – kHz Power-On Characteristics Power-On Time5 tPO VCC > VCC(min), fSIG < 200 Hz – – 1 ms Output Stage Characteristics Output On Voltage V OUT(SAT) IOUT = 10 mA, output in on-state – – 400 mV IOUT = 15 mA, output in on-state – – 450 mV Output Zener Voltage V ZOUT IOUT = 3 mA, TA = 25°C 30 – – V Output Current Limit I OUTLIM Output in on-state 30 50 80 mA Output Leakage Current I OUTOFF VOUT = 24 V, output in off-state – 0.1 10 μA Output Delay Time6 td 4 kHz sinusoidal signal, falling electrical edge – 22 – μs Output Rise Time t r RPU = 1 kΩ, CL = 4.7 nF, VPU = 5 V – 10.3 – μs Output Fall Time7 tf TA = 25°C, RPU = 1 kΩ, CL = 4.7 nF VPU = 5 V 5 8 15 μs VPU = 12 V – 15 – μs Output Fall Time Variation Over Temperature Range Δtf Maximum variation from TA = 25°C – ±0.2 – %/°C Output Polarity V OUT HT device package option Opposite target tooth – High – V Opposite target valley – Low – V LT device package option Opposite target tooth – Low – V Opposite target valley – High – V Performance Characteristics Operational Air Gap Range 8 AGTPOS TPOS functionality guaranteed 0.5 – 3.0 mm Extended Air Gap Range9 AGEXTMAX Output switching in Running Mode, TPOS function not guaranteed 3.0 – 4.5 mm Relative Timing Accuracy10,11 ErrRELR Rising mechanical edges after initial calibration, gear speed = 1000 rpm, target eccentricity < 0.1 mm – 0.4 0.8 deg. Err RELF Falling mechanical edges after initial calibration, gear speed = 1000 rpm, target eccentricity < 0.1 mm – 0.5 1.0 deg.

Self-Calibrating TPOS Speed Sensor Optimized for Automotive Cam Sensing ApplicationsATS675LSE 5Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 U.S.A. Tooth Speed f SIG Tooth signal frequency, sinusoidal input signal 0 – 8000 Hz Analog Signal Bandwidth BW Equivalent to –3 dB cutoff frequency – 20 – kHz Switchpoint Characteristics Switchpoint B ST % of peak-to-peak, referenced to tooth signal (see figure 4) –3 0 – % Internal Hysteresis12 BHYS % of peak-to-peak signal – 10 – % Calibration Initial Calibration13 CALI Quantity of mechanical falling edges during which device is in full TPOS Mode – – 4 Edges TPO to Running Mode Adjustment CAL TPORM Quantity of target teeth after CALI over which TPOS to Running Mode threshold adjustment occurs 1 – 16 Teeth Signal Characteristics Maximum Allowable Signal Reduction Breduce(G) Reduction in VPROC amplitude from VPROC(high) to lowest peak VPROC(reduce), all specifications within range (see figure 5) – – 15 %pk-pk Breduce(NG) Reduction in VPROC amplitude from VPROC(high) to lowest peak VPROC(reduce); output switches, other specifications may be out of range (see figure 5) – – 25 %pk-pk 1Typical values are at TA = 25°C and VCC = 12 V. Performance may vary for individual units, within the specified maximum and minimum limits. 2Maximum voltage must be adjusted for power dissipation and junction temperature; see Power Derating section. 3Maximum current limit is equal to ICC(max) + 3 mA. 4Negative current is defined as conventional current coming out of (sourced from) the specified device terminal. 5Power-On Time is the duration from when VCC rises above VCC(min) until a valid output state is realized. 6Output Delay Time is the duration from when a crossing of the magnetic signal switchpoint, BST , occurs to when the electrical output signal, VOUT , reaches 90% of VOUT(high). 7Characterization data shows 12 V fall time to be 1.5 times longer than 5 V fall time. See figure 2. 8The Operational Air Gap Range is the range of installation air gaps within which the TPOS (True Power-On State) function is guaranteed to correctly detect a tooth when powered-on opposite a tooth and correctly detecting a valley when powered-on opposite a valley, using reference target 8X. 9The Extended Air Gap Range is a range of installation air gaps, larger than AGTPOS, within which the device will accurately detect target features in Running Mode, but TPOS functionality is NOT guaranteed, possibly resulting in undetected target features during Initial Calibration. Relative Timing Accuracy (ErrREL) not guaranteed in Extended Air Gap Range. 10The term mechanical edge refers to a target feature, such as the side of a gear tooth, passing opposite the device. A rising edge is a transition from a valley to a tooth, and a falling edge is a transition from a tooth to a valley. See figure 7. 11Relative Timing Accuracy refers to the difference in accuracy, relative to a 0.5 mm air gap, through the entire Operational Air Gap Range. See figure 7. 12Refer to Functional Description section for a description of Internal Hysteresis. 13Signal frequency, fSIG < 200 Hz. 14Running Mode; 4X target used. The Operational Signal Amplitude, VPROC , is the internal signal generated by the Hall detection circuitry and normalized by Automatic Gain Calibration. OPERATING CHARACTERISTICS (continued) Valid using reference target 8X, TA, TJ, and VCC within specification, unless otherwise noted Characteristics Symbol Test Conditions Min. Typ. 1 Max. Unit

Worcester, Massachusetts 01615-0036 U.S.A. Figure 2. Output Rise Time and Output Fall Time Figure 3. Output Delay Time and Output Fall Time Figure 4. Switchpoint and Internal Hysteresis Figure 5. Maximum Allowable Signal Reduction. B reduce for a given tooth

Self-Calibrating TPOS Speed Sensor Optimized for Automotive Cam Sensing ApplicationsATS675LSE 7Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 U.S.A. Characteristic Performance Supply Current versus Ambient Temperature -50 -25 0 25 50 75 100 125 150 175 TA (°C) VCC (V) TA (°C) VOUT(sat) (mV) ICC (mA) 3.3 VCC (V) 15.0 Supply Current versus Supply Voltage 0 5 10 15 20 25 30 -40 150 Output Voltage (Low) versus Ambient Temperature 100 150 200 250 300 350 400 -50 -25 0 25 50 75 100 125 150 175 IOUT (mA) Relative Timing Accuracy versus Air Gap Falling Mechanical Edge, 1000 rpm, Relative to 0.5 mm Air Gap -0.4 -0.3 -0.2 -0.1 0.1 0.2 0.3 0.4 0.5 1 1.5 2 2.5 3 3.5 AG (mm) Edge Position (°) Relative Timing Accuracy versus Air Gap Rising Mechanical Edge, 1000 rpm, Relative to 0.5 mm Air Gap Relative Timing Accuracy versus Speed TA = 25°C, 1.5 mm Air Gap, Relative to 0.5 mm Air Gap -0.4 -0.3 -0.2 -0.1 0.1 0.2 0.3 0.4 0.5 1 1.5 2 2.5 3 3.5 AG (mm) Edge Position (°) -0.4 -0.3 -0.2 -0.1 0.1 0.2 0.3 0.4 0 500 1000 1500 2000 2500 Gear Speed (rpm) Edge Position (°) TA (°C) -40 150 TA (°C) -40 150 TA (°C) Falling Rising Mechanical Edge Output Fall Time Versus Ambient Temperature RPU =1k Ω,C L =4 . 7n F 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 -50 -25 0 25 50 75 100 125 150 175 TA (°C) tf (us) VPU (V)

Worcester, Massachusetts 01615-0036 U.S.A. Figure 6. Configuration with Reference Target

Worcester, Massachusetts 01615-0036 U.S.A. on the same silicon substrate by a proprietary BiCMOS process. the stable amplifier design and the offset rejection circuitry. information on EMC specification compliance. mization is needed and minimal processing circuitry is required. costs for most applications. option.. This is illustrated in figure 8. Figure 7. Application cross-section: (A) target tooth opposite device, and Figure 8. Sensor output polarity and switch state (with device connected opposite (device off)—polarity response inverts with the HT option.

10Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 U.S.A. target mechanical edge that is opposite the device after power-on. switchpoint can be accurately computed. target particularities, such as small mechanical valleys. Figure 9. Startup calibration order Figure 10. Output switching can accommodate an anomalous peak, such as the middle peak in this figure, by using the Internal Hysteresis value.

11Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 U.S.A. magnetic map of the 8X reference target. ing the minimum tooth signal to the maximum valley signal. Figure 11. Magnetic Data for the 8X Reference Target and SE package. Flux density measurements are relative to the baseline magnetic field.

Self-Calibrating TPOS Speed Sensor Optimized for Automotive Cam Sensing ApplicationsATS675LSE 12Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 U.S.A. Power Derating The device must be operated below the maximum junction temperature of the device, T J(max). Under certain combinations of peak conditions, reliable operation may require derating supplied power or improving the heat dissipation properties of the appli- cation. This section presents a procedure for correlating factors affecting operating T J. (Thermal data is also available on the Allegro MicroSystems website.) The Package Thermal Resistance, RθJA, is a figure of merit sum- marizing 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, R θJC, is relatively small component of RθJA. 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 T J, at PD. P D = VIN × IIN (1) ΔT = PD × RθJA (2) T J = TA + ΔT (3) For example, given common conditions such as: TA= 25°C, VCC = 12 V, ICC = 7 mA, and RθJA = 77 °C/W, then: PD = VCC × ICC = 12 V × 7 mA = 84 mW Δ T = PD × RθJA = 84 mW × 77 °C/W = 6.5°C TJ = TA + ΔT = 25°C + 6.5°C = 31.5°C A worst-case estimate, PD(max), represents the maximum allow- able power level, without exceeding TJ(max), at a selected RθJA and TA. Example: Reliability for VCC at TA = 150°C. Observe the worst-case ratings for the device, specifically: RθJA = 101 °C/W, TJ(max) = 165°C, VCC(max) = 24 V , and ICC(max) = 10 mA. Calculate the maximum allowable power level, PD(max). First, invert equation 3: ΔT(max) = 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: P D(max) = ΔT(max) ÷ RθJA = 15°C ÷ 101 °C/W = 148.5 mW Finally, invert equation 1 with respect to voltage: V CC(est) = PD(max) ÷ ICC(max) = 148.5 mW ÷ 10 mA = 14.9 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 RθJA. If VCC(est) ≥ VCC(max), then operation between VCC(est) and VCC(max) is reliable under these conditions.

Self-Calibrating TPOS Speed Sensor Optimized for Automotive Cam Sensing ApplicationsATS675LSE 13Allegro MicroSystems, Inc. Worcester, Massachusetts 01615-0036 U.S.A. 10.00 0.70.7 1.27 5.5 2.0 1.6 7.00 5.7 3.3 4.9 6.2 11.6 0.6 1.3 1.5 1.5 0.38 0.9 431 24.65 A A A B C C D B Dambar removal protrusion (16X) Metallic protrusion, electrically connected to pin 4 and substrate (both sides) Active Area Depth, 0.43 mm Thermoplastic Molded Lead Bar for alignment during shipment E Hall element (not to scale) D E All dimensions nominal, not for tooling use Dimensions in millimeters Exact case and lead configuration at supplier discretion within limits shown Package SE 4-Pin SIP Module Copyright ©2008, Allegro MicroSystems, Inc. The products described herein are manufactured under one or more of the following U.S. patents: 5,045,920; 5,264,783; 5,442,283; 5,389,889; 5,581,179; 5,517,112; 5,619,137; 5,621,319; 5,650,719; 5,686,894; 5,694,038; 5,729,130; 5,917,320; and other patents pending. Allegro MicroSystems, Inc. reserves the right to make, from time to time, such de par tures from the detail spec i fi ca tions as may be required to per- mit improvements in the per for mance, 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 in for ma tion in clud ed herein is believed to be ac cu rate and reliable. How ev er, Allegro MicroSystems, Inc. assumes no re spon si bil i ty for its use; nor for any in fringe ment 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