A19520 ALLEGRO
Document overview
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Technical content
The A19520 is an advanced vibration-tolerant Hall-effect integrated circuit (IC) that measures the speed and direction of rotating targets. This sensor IC can directly measure ring magnets or be back-biased with a magnet to measure ferrous targets. The package features an integrated capacitor for electromagnetic compatibility (EMC). The A19520 employs intelligent algorithms that allow stable operation during vibration and highly dynamic air gap environments common to transmission applications. In addition, the A19520 differential sensing offers inherent rejection of interfering common-mode magnetic fields. The IC has been designed to a certified ISO 26262:201 1 design process to allow easy integration into high safety level systems. Integrated diagnostics are used to detect an IC failure that impacts the output protocol’s accuracy, providing coverage compatible with ASIL B compliance. The A19520 is provided in a 2-pin miniature SIP package (suffix UB) that is lead (Pb) free, with tin leadframe plating. The UB package includes an IC and capacitor integrated into a single overmolded package, with an additional molded lead-stabilizing bar for robust shipping and ease of assembly. A19520-DS MCO-0000530
- Differential Hall-effect sensor measures ring magnets and ferrous targets with inherent stray field immunity
- SolidSpeed Digital Architecture™ provides robust, adaptive performance with advanced algorithms that provide vibration immunity over the full target pitch
- Integrated solution includes a capacitor in a single overmolded miniature package
- ISO 26262:2011 ASIL B with integrated diagnostics and certified safety design process
- Two-wire current source output pulse-width protocol supporting speed, direction, and ASIL error reporting
- EEPROM enables factory traceability Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor IC Functional Block Diagram A19520 FEATURES AND BENEFITS DESCRIPTION December 17, 2018 PACKAGE: Not to scale 2-Pin SIP (suffix UB) Oscillator ADC Digital Controller Output Current Generator ESD VCC GND EEPROM Front End Amplification Analog-to-Digital and Signal Conditioning Regulator Diagnostics ADC
Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor ICA19520 Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A. www.allegromicro.com SELECTION GUIDE* Part Number Packing A19520LUBBTN-FSNHPYUE-A Tape and reel, 4000 pieces per reel A19520LUBBTN-RSNHPYUE-A Tape and reel, 4000 pieces per reel A19520LUBBTN-FSNHPYUE Tape and reel, 4000 pieces per reel A19520LUBBTN-RSNHPYUE Tape and reel, 4000 pieces per reel * Not all combinations are available. Contact Allegro sales for availability and pricing of custom programming options. Configuration Options A19520 F– Forward, pin 1 to pin 2 R– Forward, pin 2 to pin 1 Rotation Direction: LT N- Packing Instructions Package Designation Operating Temperature Range Allegro Identifier and Device Type Pulse Widths (Typical): UBB Magnetic Temperature Compensation: G– 0.04%/°C 0.16%/°CE –S ingle, one pulse per magnetic pole pair Number of Pulses: S I – Intermediate, Forward = 60 µs, Reverse = 120 µs, Non-Direction = 30 µs N – Narrow, Forward = 45 µs, Reverse = 90 µs, Non-Direction = 180 µs W –Wide, Forward = 45 µs, Reverse = 180 µs, Non-Direction = 360 µs Vibration Immunity / Direction Change: L – Low vibration immunity with immediate direction change detection H – High vibration immunity Running Mode Non-Direction Pulses: B – Blanked, no output during Running mode P – Pulses allowed during Running mode Extended Sudden Air Gap: K – Timed resets enabled U – Feature not enabled Calibration Mode Non-Direction Pulses: O – Blanked, no output during Calibration Y – Pulses allowed during Calibration ASIL Protocol: [blank]– ASIL protocol disabled ASIL protocol enabled-A
Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor ICA19520 Allegro MicroSystems, LLC Manchester, NH 03103-3353 U.S.A. www.allegromicro.com ABSOLUTE MAXIMUM RATINGS Characteristic Symbol Notes Rating Unit Supply Voltage VCC Refer to Power Derating section 28 V Reverse Supply Voltage VRCC –18 V Operating Ambient Temperature TA –40 to 150 °C Maximum Junction Temperature TJ(max) 165 °C Storage Temperature Tstg –65 to 170 °C INTERNAL DISCRETE CAPACITOR RATINGS Characteristic Symbol Test Conditions Value (Typ.) Unit Nominal Capacitance CSUPPLY Connected between pin 1 and pin 2 (refer to Figure 1) 10 nF Figure 1: Typical Application Circuit VSUPPLY GND RL CSUPPLY IC CL A19520 Terminal List Table Name Number Function VCC 1 Supply Voltage GND 2 Ground 2 1 PINOUT DIAGRAM AND TERMINAL LIST
Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor ICA19520 Allegro MicroSystems, LLC Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Characteristic Symbol Test Conditions Min. Typ. [1] Max. Unit GENERAL Supply Voltage [2] VCC Operating, TJ < TJ(max), voltage across pin 1 and pin 2; does not include voltage across RL 4 – 24 V Undervoltage Lockout VCC(UV) VCC 0 V → 5 V or 5 V → 0 V – 3.6 3.95 V Reverse Supply Current [3] IRCC VCC = VRCC(max) –10 – – mA Supply Current ICC(LOW) Low-current state 5.9 7 8 mA ICC(HIGH) High-current state 12 14 16 mA ICC(HIGH) / ICC(LOW) Ratio of high current to low current (isothermal) 1.9 – – – ASIL Safety Current IRESET Refer to Figure 15 1.5 – 3.9 mA PROTECTION CIRCUITS Supply Zener Clamp Voltage VZsupply ICC = 19 mA, TA = 25°C 28 – – V POWER-ON CHARACTERISTICS Power-On State POS VCC > VCC(min), as connected in Figure 1 ICC(LOW) mA Power-On Time [4] tPO Time from VCC > VCC(min), until device has entered calibration – – 1 ms OUTPUT PULSE CHARACTERISTICS, PULSE PROTOCOL [5] Output Rise Time tr Voltage measured at pin 2 in Figure 1, RL = 100 Ω, CL = 10 pF, measured between 10% and 90% of signal 0 2 4 μs Output Fall Time tr Voltage measured at pin 2 in Figure 1, RL = 100 Ω, CL = 10 pF, measured between 10% and 90% of signal 0 2 4 μs Pulse Width, ASIL Warning tw(ASILwarn) Refer to Figure 15 63 – 121 μs Pulse Width, ASIL Critical tw(ASILcrit) Refer to Figure 15 4 – 8 ms OPERATING CHARACTERISTICS : Valid throughout full operating and temperature ranges, unless otherwise specified Continued on next page...
Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor ICA19520 Allegro MicroSystems, LLC Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Characteristic Symbol Test Conditions Min. Typ. [1] Max. Unit INTERMEDIATE PULSE WIDTH OPTION (PART NUMBER - xxIxxxxx) Threshold to Enter High-Speed Mode fHIGH TCYCLE frequency increasing 0.935 1.1 1.265 kHz Threshold to Exit High-Speed Mode fLOW TCYCLE frequency decreasing 0.850 1 1.150 kHz Pulse Width, Forward Rotation tw(FWD) TCYCLE frequency < fLOW 51 60 69 μs Pulse Width, Reverse Rotation tw(REV) TCYCLE frequency < fLOW 102 120 138 μs Pulse Width, High-Speed tw(HS) TCYCLE frequency > fHIGH 25 30 35 μs Pulse Width, Non-Direction tw(ND) 25 30 35 μs Operating Frequency, Forward Rotation [6][7][8] fFWD 0 ̶ 12 kHz Operating Frequency, Reverse Rotation [6][7][8] fREV 0 ̶ 12 kHz Operating Frequency, Non-Direction Pulses [6][8] fND 0 ̶ 12 kHz NARROW PULSE WIDTH OPTION (PART NUMBER - xxNxxxxx) Pulse Width, Forward Rotation tw(FWD) 38 45 52 μs Pulse Width, Reverse Rotation tw(REV) 76 90 104 μs Pulse Width, Non-Direction tw(ND) 153 180 207 μs Operating Frequency, Forward Rotation [6][8] fFWD 0 ̶ 12 kHz Operating Frequency, Reverse Rotation [6][8] fREV 0 ̶ 7 kHz Operating Frequency, Non-Direction Pulses [6][8] fND 0 ̶ 4 kHz WIDE PULSE WIDTH OPTION (PART NUMBER - xxWxxxxx) Pulse Width, Forward Rotation tw(FWD) 38 45 52 μs Pulse Width, Reverse Rotation tw(REV) 153 180 207 μs Pulse Width, Non-Direction tw(ND) 306 360 414 μs Operating Frequency, Forward Rotation [6][8] fFWD 0 ̶ 12 kHz Operating Frequency, Reverse Rotation [6][8] fREV 0 ̶ 4 kHz Operating Frequency, Non-Direction Pulses [6][8] fND 0 ̶ 2.2 kHz [1] Typical values are at TA = 25°C and VCC = 12 V. Performance may vary for individual units, within the specified maximum and minimum limits. [2] Maximum voltage must be adjusted for power dissipation and junction temperature; see representative for Power Derating discussions. [3] Negative current is defined as conventional current coming out of (sourced from) the specified device terminal. [4] Output transients prior to tPO should be ignored. [5] Timing from start of rising output transition. Measured pulse width will vary on load circuit configurations and thresholds. Pulse width measured at threshold of (ICC(HIGH) + ICC(LOW)) / 2 for non-ASIL pulses and (IRESET + ICC(LOW)) / 2 for ASIL pulses. [6] Maximum Operating Frequency is determined by satisfactory separation of output pulses. If shorter low-state durations can be resolved, the maximum fREV and fND may be higher, excluding the -xxIxxxx variant or f(FWD) as filter bandwidth limitation applies. [7] Direction information is not available when frequency > fHIGH for the Intermediate Pulse Width option. [8] Zero-speed is not met when the K-variant is implemented due to the inclusion of a timed reset. OPERATING CHARACTERISTICS (continued): Valid throughout full operating temperature ranges, unless otherwise specified
Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor ICA19520 Allegro MicroSystems, LLC Manchester, NH 03103-3353 U.S.A. www.allegromicro.com OPERATING CHARACTERISTICS (continued): Valid throughout full operating temperature ranges, unless otherwise specified Characteristic Symbol Test Conditions Min. Typ. [1] Max. Unit INPUT CHARACTERISTICS AND PERFORMANCE Operating Differential Magnetic Input [8] BDIFF(pk-pk) Peak-to-peak of differential magnetic input 30 – – G Operating Differential Magnetic Range [8] BDIFF Differential input signal; refer to Figure 5 –750 – 750 G Allowable Differential Sequential Signal Variation BSEQ(n+1) / BSEQ(n) Signal cycle-to-cycle variation (refer to Figure 2) 0.7 – 1.3 – BSEQ(n+i) / BSEQ(n) Overall signal variation (refer to Figure 2) 0.1 – – – Operate Point BOP % of peak-to-peak IC-processed signal – 70 – % Release Point BRP % of peak-to-peak IC-processed signal – 30 – % Switch Point Separation BDIFF(SP-SEP) Required amount of amplitude separation between channels at each B OP and BRP occurrence; refer to Figure 4 20 – – %BDIFF(pk-pk) Initial Calibration TCAL Periods after tPO completed and first valid speed and direction output. Constant direction of rotation. Refer to Figure 3 for definition of t CYCLE. – – 4 × TCYCLE Vibration Immunity (Startup) High Vibration (-xxxHxxxx variant) 1 × TCYCLE – – – Low Vibration (-xxxLxxxx variant) 1 × TCYCLE – – – Vibration Immunity (Running Mode) High Vibration (-xxxHxxxx variant) 1 × TCYCLE – – – Low Vibration (-xxxLxxxx variant) 0.12 × TCYCLE – – – THERMAL CHARACTERISTICS Magnetic Temperature Coefficient [9] TC Based on magnetic material makeup (-xxxxxxxE variant) – 0.16 – %/°C Based on magnetic material makeup (-xxxxxxxG variant) – 0.04 – %/°C Package Thermal Resistance [10] RθJA Single-layer PCB with copper limited to solder pads – 213 – °C/W [8] Differential magnetic field is measured for Channel A (E1-E2) and Channel B (E2-E3) independently. Refer to Figure 5. Each channel’s differential magnetic field is measured between two Hall elements with spacing determined by Figure 16. Magnetic field is measured orthogonally to the front of the package. [9] Magnets and magnetic encoders decrease in magnetic strength with rising temperature. The device temperature coefficient compensates, to help maintain a consistent air gap over temperature. [10] Additional thermal information is available on the Allegro website.
Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor ICA19520 Allegro MicroSystems, LLC Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Figure 2: Differential Signal Variation B SEQ(n) B SEQ(n + 1) B, i≥2SEQ(n+i) Target SNSN TCYCLE TCYCLE BDIFF BDIFF = Differential Input Signal; the differential magnetic = Target Cycle; the amount of rotation that flux sensed by the sensor moves one north pole and one south pole across the sensor Figure 3: Definition of TCYCLE Figure 4: Definition of Switch Point Separation BDIFF(BRP) BDIFF(BOP) BDIFF(pk-pk) BDIFF(pk-pk) BDIFF(SP) BDIFF(SP) BDIFF(SP)B=DIFF(SP-SEP) (B )OP (B )RP TCYCLE Channel A Channel B SNS N Figure 5: Differential Magnetic Input 0 G BDIFF(max) BDIFF(min) Time Applied BDIFF BDIFF BDIFF(pk-pk)
Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor ICA19520 Allegro MicroSystems, LLC Manchester, NH 03103-3353 U.S.A. www.allegromicro.com FUNCTIONAL DESCRIPTION The A19520 sensor IC contains a single-chip Hall-effect circuit that supports three Hall elements. These elements are used in differential pairs to provide electrical signals containing informa- tion regarding speed, direction of target rotation, and edge posi- tion. The A19520 is intended for use with ring magnet targets, or, when back-biased with an appropriate magnet, with ferrous targets. The IC detects the peaks of the magnetic signals and sets dynamic thresholds based on these detected signals. Output edges are triggered by B DIFF transitions through the switch points. ROTATION DIRECTION When the target is rotating such that a target feature passes from pin 1 to pin 2, this is referred to as forward rotation. This direc- tion of rotation is indicated on the IC output by a t w(FWD) pulse width. For the “-Rxxxxxxx” variant, forward direction is indi- cated for target rotation from pin 2 to 1. General Protocol Description When a target passes in front of the device (opposite the branded face of the package case), the sensor IC generates an output pulse for each magnetic pole-pair of the target or for each tooth-valley pair. 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. For the “-xxIxxxxx” variant, when in High Speed Mode, output pulses will be of t w(HS) duration for either target direction of rota- tion. Refer to Figure 6 for target orientation to the device and Figure 7 through Figure 9 for a general output protocol understanding. Figure 6: Target Orientation Relative to Device (ring magnet shown). N N NN N S S S SS N N NN N S S S SS (A) Forward Rotation (-Fxxxxxxx variant) (B) Reverse Rotation (-Fxxxxxxx variant) Branded Face of Sensor Branded Face of Sensor Pin 1 Pin 2 Pin 1 Pin 2 Rotating Target Rotating Target Figure 7: Output Protocol (-Fxxxxxxx), No High Speed Mode, Forward Rotation Figure 8: Output Protocol (-Fxxxxxxx), No High Speed Mode, Reverse Rotation Figure 9: Output Protocol (-xxIxxxxx), High Speed Mode Target Rotaon (Reverse) N S NS S ICC(HIGH) ICC(LOW) tw(HS) tw(HS) or Target Rotaon (Forward) Target Rotaon (Forward) N S NS S ICC(HIGH) ICC(LOW) tw(FWD) tw(FWD) Target Rotaon (Reverse) N S NS S ICC(HIGH) ICC(LOW) tw(REV) tw(REV)
Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor ICA19520 Allegro MicroSystems, LLC Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Figure 10: Basic Operation BOP BOP BOP ICC(Low) ICC(High) BRP BRP Device Orientation to Target IC (Pin 1 Side)(Pin 2 Side) A Channel Element Pitch B Channel Element Pitch Package Case Branded Face Target Magnetic Profile Mechanical Position (Target moves past device pin 1 to pin 2) S NN Target (Radial Ring Magnet) This pole sensed earlier This pole sensed later (Top View of Package Case) Channel Element Pitch B Channel A Channel B Channel A Channel E1E2 E3 N IC Internal Differential Analog Signals, VPROC Detected Channel Switching Device Output Signal ICC(High) ICC(Low) BRP BOP BRP BOP Device Orientation to Target (Pin 1 Side) (Pin 2 Side) IC A ChannelB Channel Pole Piece (Concentrator) Package Case Branded Face (Top View of Package Case) Back-Biasing Rare-Earth Pellet Channel Element Pitch A Channel B Channel A Channel B Channel Mechanical Position (Target moves past device pin 1 to pin 2) This tooth sensed earlier This tooth sensed later IC E1E2E3 IC Internal Differential Analog Signals, VPROC Detected Channel Switching Device Output Signal Target Magnetic Profile North Pole South Pole Target BRP
Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor ICA19520 Allegro MicroSystems, LLC Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Startup Detection/Calibration After proper supply voltage is applied to the IC, the IC detects the magnetic profile of the rotating target. The calibration period occurs on the first few features of the target that pass in front of the IC. Direction information is available after calibration is complete. Figure 11 and Figure 12 show where the first output edges may occur for various starting target phases. Figure 11: Startup Position Effect on First Device Output Switching (-xxxxxOxx variant) Figure 12: Startup Position Effect on First Device Output Switching (-xxxxxYxx variant) t ICC Target Differential Magnetic Profile Target Rotation Opposite north pole Opposite N→S boundary Opposite south pole Opposite S→N boundary Device Location at Power-On 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) N S N S N S N S N t ICC Target Differential Magnetic Profile Target Rotation Opposite north pole Opposite N→S boundary Opposite south pole Opposite S→N boundary Device Location at Power-On tW(FWD) or tW(REV) tW(ND)tW(ND) tW(ND) tW(ND) tW(FWD) or tW(REV) tW(FWD) or tW(REV) tW(ND) tW(FWD) or tW(REV) tW(FWD) or tW(REV) tW(ND) tW(ND) tW(ND) tW(FWD) or tW(REV) tW(FWD) or tW(REV) N S N S N S N S N
Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor ICA19520 Allegro MicroSystems, LLC Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Vibration Detection Algorithms embedded in the IC’s digital controller detect the pres- ence of target vibration (oscillation) through analysis of the two magnetic input channels. With low vibration option, during any detected vibration, the out- put is blanked and no output pulses will occur for vibrations less than the specified vibration immunity. Output pulses containing the proper direction information will resume when direction informa- tion is validated on constant target rotation. With High vibration mode, advanced algorithm detection provides additional immunity. As shown in Figure 14, the IC may produce tND pulses, depending on the vibration amplitude. Figure 13: Output Functionality in the Presence of Running Mode Target Vibration – Low Vibration Immunity (-xxxLBxxx variant) Figure 14: Output Functionality in the Presence of Running Mode Target Vibration – High Vibration Immunity (-xxxHxxxx variant) Normal Target Rotation Normal Target Rotation Normal Target Rotation Normal Target Rotation Vibration Vibration Target Differential Magnetic Profile Target Differential Magnetic Profile N N N N N N N N S S S S S S S S t t t [or t [or t [or t [or t [or t [or t [or t [or t [or t [or t [or t t t t t t t t t t t t t t W W W W W W W W W W W W W W W W W W W W W W W W W W W (FWD) (FWD) (FWD) (REV)] (REV)] (REV)] (REV)] (REV)] (REV)] (FWD)] (REV)] (REV)] (REV)] (REV)] (FWD) (FWD) (FWD) (REV) (ND) (ND) (ND) (FWD) (ND) (FWD) (ND) (FWD) (FWD) t t t [or t [or t [or t t tW W W W W W(FWD) (REV)] (REV)] (REV)] (FWD) (FWD) t -xxxHPxxx Variant -xxxHBxxx Variant
Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor ICA19520 Allegro MicroSystems, LLC Manchester, NH 03103-3353 U.S.A. www.allegromicro.com ASIL Protocol The A19520 sensor IC contains diagnostic circuitry that will continuously monitor occurrences of failure defects within the IC. Refer to Figure 15 for the output protocol of the ASIL Safe State after an internal defect has been detected. Error Protocol will result from faults which cause incorrect signal transmission (i.e., too few or too many output pulses). Note: If a fault exists continuously, the device will attempt recov- ery indefinitely. Refer to the A19520 Safety Manual for additional details on the ASIL Safe State Output Protocol. Figure 15: Output Protocol (ASIL Safe State) NN N N NS Ring Magnet S S SS S Normal Operation ICC(HIGH) ICC(LOW) Fault Protocol ICC(HIGH) ICC(LOW) Fault tw(ASILwarn ) or tw(ASILcrit) IRESET tPO
Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor ICA19520 Allegro MicroSystems, LLC Manchester, NH 03103-3353 U.S.A. www.allegromicro.com The device must be operated below the maximum junction tem- perature 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 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 a rela- tively 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 or PD), can be estimated. The following formulas represent the fundamental relationships used to estimate TJ, at PD. PD = VIN × IIN (1) ΔT = PD × RθJA (2) TJ = TA + ΔT (3) For example, given common conditions such as: TA= 25°C, VCC = 12 V, ICC = 14 mA, and RθJA = 213°C/W, then: PD = VCC × ICC = 12 V × 14 mA = 168 mW ΔT = PD × RθJA = 168 mW × 213°C/W = 35.8°C A worst-case estimate, PD(max), represents the maximum allow- able power level (VCC(max), ICC(max)), without exceeding TJ(max), at a selected RθJA and TA. Example: Reliability for VCC at TA = 150°C, package UB, using 1-layer PCB. Observe the worst-case ratings for the device, specifically: RθJA = 213°C/W, TJ(max) = 165°C, VCC(max) = 24 V , and ICC(A VG) = 14.6 mA. ICC(A VG) is computed using ICC(HIGH)(max) and ICC(LOW)(max), with a duty cycle of 83% computed from tw(REV)(max) on-time at 4 kHz maximum operating frequency. Calculate the maximum allowable power level (PD(max) ). First, invert equation 3: ΔTmax = 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) = ΔTmax ÷ RθJA = 15°C ÷ 213°C/W = 70.4 mW Finally, invert equation 1 with respect to voltage: VCC(est) = PD(max) ÷ ICC(AVG) = 70.4 mW ÷ 14.6 mA = 4.8 V The result indicates that, at TA, the application and device can dissipate adequate amounts of heat above 6.5 V at 150°C. Compare VCC(est) to VCC(max). If VCC(est) ≤ VCC(max), then reli- able 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. POWER DERATING 20 40 60 80 100 120 140 160 180 Maximum Allowable VCC (V) Temperature (°C) Power Derating Curve VCC(max) VCC(min) 1-layer PCB, Package UB (RθJA = 213°C/W) 200 400 600 800 1000 1200 1400 20 40 60 80 100 120 140 160 180 Power Dissipation, PD (mW) Temperature (°C) Power Dissipation versus Ambient Temperature 1-layer PCB, Package UB (RθJA = 213°C/W)
Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor ICA19520 Allegro MicroSystems, LLC Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Figure 16: Package UB, 2-Pin SIP For Reference Only –N ot for Tooling Use (Reference DWG-0000408, Rev. 3) Dimensions in millimeters – NOT TO SCALE Dimensions exclusive of moldfl ash, gate burs, and dambar protrusions Exact case and lead configuration at supplier discretion within limits shown Mold Ejector Pin Indent A B C D E F Dambar removal protrusion (8×) Gate and tie burr area Hall elements (E1, E2, and E3); not to scale Molded Lead Bar for preventing damage to leads during shipment Active Area Depth, 0.38 mm ±0.03 Branding scale and appearance at supplier discretion
0.25 REF
0.30 REF
4 × 2.50 ±0.10 4 × 7.37 REF 4 × 0.85 REF
0.38 REF
45° 0.85 ±0.05 0.85 ±0.05 B 4×10° A Branded Face 0.25 +0.07 –0.03 0.42 ±0.05 4.00 4.00 4.00 1.00 ±0.05 1.80 ±0.10
2.54 REF
12.20 ±0.10 1.80 1.50 ±0.05 1.50 ±0.05 C F E1 E3 1.50 1.50 E E E E E 0.50 E 1.39 E D Lines 1, 2, 3 = Max 5 characters per line Line 1: 5-digit Part Number Line 2: 4-digit Date Code Line 3: Characters 5, 6, 7, 8 of Asembly Lot Number Standard Branding Reference View Date Code Lot Number 19550 +0.06 –0.05 +0.06 –0.07 +0.06 –0.07 +0.06 –0.05 18.00 ±0.10 PACKAGE OUTLINE DRAWING
Vibration-Tolerant Hall-Effect Transmission Speed and Direction Sensor ICA19520 Allegro MicroSystems, LLC Manchester, NH 03103-3353 U.S.A. www.allegromicro.com
Revision History
– December 17, 2018 Initial release For the latest version of this document, visit our website: www.allegromicro.com Copyright ©2018, 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 any devices or systems, including but not limited to life support devices or systems, in which a failure of Allegro’s product can reasonably be expected to cause bodily harm. 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. Copies of this document are considered uncontrolled documents.