A19200 ALLEGRO
Document overview
- Manufacturer or author: Provided By www.digicamel.com(free datasheet download site)
- PDF pages: 12
Technical content
The A19200 is a Hall-effect-based integrated circuit (IC) that provides a user-friendly solution for true zero-speed digital ring magnet sensing in two-wire applications. The A19200 is offered in the UB package, which integrates the IC and a high temperature ceramic capacitor in a single overmolded SIP package. The integrated capacitor provides enhanced EMC performance with reduced external components. The IC is ideally suited for obtaining speed information in wheel speed applications. The Hall element spacing is optimized for high resolution, small diameter targets. The package is lead (Pb) free, with tin leadframe plating. A19200-DS, Rev. 2 MCO-0000953
- Integrated diagnostics and certified safety design process for ASIL B(D) compliance
- Integrated capacitor reduces need for external EMI protection components
- True zero-speed operation
- Single chip sensing IC for high reliability
- Fully synchronous digital logic with Scan and IDDQ testing
- Application-proven algorithms for robust operation in wheel speed environments ASIL-Compliant Wheel Speed Sensor IC PACKAGE : 2-pin SIP (suffix UB) Functional Block Diagram Not to scale A19200 VCC GND Amp AGCOffset Adjust Output Control Analog to Digital Converter Digital Controller Internal Regulator FEATURES AND BENEFITS DESCRIPTION April 11, 2022
ASIL-Compliant Wheel Speed Sensor ICA19200 Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A. www.allegromicro.com SELECTION GUIDE Part Number Packing Power-On State Fault Detection Mode A19200LUBATN-L 4000 pieces per 13-in. reel ICC(LOW) Disabled A19200LUBATN-H 4000 pieces per 13-in. reel ICC(HIGH) Disabled A19200LUBATN-L-A 4000 pieces per 13-in. reel ICC(LOW) Enabled A19200LUBATN-H-A 4000 pieces per 13-in. reel ICC(HIGH) Enabled A19200 L UB A TN - Configuration Options Fault Detection Mode: ASIL Protocol Enabled ASIL Protocol Disabled Power-On State: High Low Packing Instructions Internal Capacitor Value Package Designation Operating Temperature Range Allegro Identifier and Device Type
ASIL-Compliant Wheel Speed Sensor ICA19200 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Terminal List Table Name Number Function VCC 1 Supply Voltage GND 2 Ground INTERNAL DISCRETE CAPACITOR RATINGS Characteristic Symbol Test Conditions Value (Typ.) Unit Nominal Capacitance CSUPPLY Connected between VCC and GND 2.2 nF ABSOLUTE MAXIMUM RATINGS Characteristic Symbol Notes Rating Unit Supply Voltage VCC 28 V Reverse Supply Voltage VRCC –18 V Operating Ambient Temperature TA L temperature range –40 to 150 °C Maximum Junction Temperature TJ(max) 165 °C Storage Temperature Tstg –65 to 170 °C
ASIL-Compliant Wheel Speed Sensor ICA19200 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Characteristic Symbol Test Conditions Min. Typ. [1] Max. Unit
ELECTRICAL CHARACTERISTICS
Supply Voltage [2] VCC Operating, TJ < TJ(max) 4.0 – 24 V Undervoltage Lockout VCC(UV) VCC 0 → 5 V or 5 → 0 V – 3.6 3.95 V Reverse Supply Current [3] IRCC VCC = VRCC(max) – – –10 mA Supply Zener Clamp Voltage VZSUPPLY ICC = ICC(max) + 3 mA, TA = 25°C 28 – – V Supply Zener Current IZSUPPLY TA = 25°C, VCC = 28 V – – 19 mA OUTPUT Power-On State POS -H variant – ICC(HIGH) – – -L variant – ICC(LOW) – – Supply Current ICC(LOW) Low-current state 5.9 – 8.4 mA ICC(HIGH) High-current state 12 – 16 mA Supply Current Ratio ICC(HIGH) / ICC(LOW) Measured as ratio of high current to low current (isothermal) 1.9 – – – ASIL Safety Current IFAULT 1.0 – 3.3 mA Output Rise, Fall Time tr , tf Corresponds to measured output slew rate with CSUPPLY; RLOAD = 100 Ω, CL = 10 pF 0 – 1.5 μs OPERATING CHARACTERISTICS Operate Point BOP % of peak-to-peak IC-processed magnetic signal – 60 – % Release Point BRP % of peak-to-peak IC-processed magnetic signal – 40 – % Operating Frequency fFWD 0 – 5 kHz Figure 1: Typical Application Circuit A19200 VCC VCC GND RL 100 Ω CL Continued on the next page… OPERATING CHARACTERISTICS: Valid throughout full operating and temperature ranges, unless otherwise specified
ASIL-Compliant Wheel Speed Sensor ICA19200 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Characteristic Symbol Test Conditions Min. Typ. [1] Max. Unit OPERATING CHARACTERISTICS (continued) Input Signal BSIG Differential signal, measured peak-to-peak 20 – 1200 G Allowable User-Induced Differential Offset BSIGEXT External differential signal bias (DC), operating within specification –300 – 300 G Sensitivity Temperature Coefficient [4] TC – +0.2 – %/°C Total Pitch Deviation For constant BSIG, sine wave – – ±2 % Maximum Sudden Signal Amplitude Change BSEQ(n+1) / BSEQ(n) No missed output edge. Instantaneous symmetric magnetic signal amplitude change, measured as a percentage of peak-to-peak BSIG (see Figure 2) – 0.6 – – Allowable Differential Signal Amplitude Variation BSEQ(min) / BSEQ(max) Overall symmetric magnetic signal amplitude ratio of BSIG – 0.2 – – [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 discussions in Power Derating section. [3] Negative current is defined as conventional current coming out of (sourced from) the specified device terminal. [4] Ring magnets decrease strength with rising temperature. Device compensates. Note that BSIG requirement is not influenced by this. BSEQ(n) BSEQ(n+1) Figure 2: Differential Signal Variation OPERATING CHARACTERISTICS (continued): Valid throughout full operating and temperature ranges, unless otherwise specified
ASIL-Compliant Wheel Speed Sensor ICA19200 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com THERMAL CHARACTERISTICS Characteristic Symbol Test Conditions* Value Unit Package Thermal Resistance RθJA Single-layer PCB with copper limited to solder pads 213 °C/W *Additional thermal information is available on the Allegro website. 20 40 60 80 100 120 140 160 180 Temperature (ºC) Maximum Allowable V (V) CC VCC(max) VCC(min) Power Derating Curve 20 40 60 80 100 120 140 160 180 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 Temperature (ºC) Power Dissipation P (mW) D Power Dissipation versus Ambient Temperature
ASIL-Compliant Wheel Speed Sensor ICA19200 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com FUNCTIONAL DESCRIPTION Hall Technology This single-chip differential Hall-effect sensor IC contains two Hall elements as shown in Figure 3, which simultaneously sense the magnetic profile of the ring magnet or gear target. The mag- netic fields are sensed at different points (spaced at a 1.75 mm pitch), generating a differential internal analog voltage, VPROC , that is processed for precise switching of the digital output signal. The Hall IC is self-calibrating and also possesses a temperature- compensated amplifier and offset cancellation circuitry. Its voltage regulator provides supply noise rejection throughout the operating voltage range. Changes in temperature do not greatly affect this device due to the stable amplifier design and the offset rejection circuitry. The Hall transducers and signal processing electronics are integrated on the same silicon substrate, using a proprietary BiCMOS process. Target Profiling During Operation An operating device is capable of providing digital information that is representative of the mechanical features of a rotating gear or ring magnet. The waveform diagram in Figure 5 presents the automatic translation of the mechanical profile, through the magnetic profile that it induces, to the digital output signal of the A19200. No additional optimization is needed and minimal pro- cessing circuitry is required. This ease of use reduces design time and incremental assembly costs for most applications. Determining Output Signal Polarity In Figure 5, the top panel, labeled Mechanical Position, repre- sents the mechanical features of the ring magnet or gear target and orientation to the device. The bottom panel, labeled Device Output Signal, displays the square waveform corresponding to the digital output signal that results from a rotating target configured as shown in Figure 4. That direction of rotation (of the target side adjacent to the package face) is: perpendicular to the leads, across the face of the device, from the pin 1 side to the pin 2 side. This results in the device output switching from high to low output state as a north magnetic pole passes the device face. In this configuration, the device output voltage switches to its high polarity when a south pole is the target feature nearest to the device. If the direction of rotation is reversed or if a part of type A19200LUBx-L is used, then the output polarity inverts (see Table 1). Figure 3: Relative Motion of the Target Relative Motion of the Target is detected by the dual Hall elements mounted on the Hall IC. Figure 4: Target Orientation Relative to Device (ring magnet shown). S N S NRing Magnet Target Ferromagnetic Target Tooth Valley Pin 1 Side Pin 2 Side Package Case Branded Face Hall Element 2 Hall Element 1 Element Pitch (Top View of Package Case) Back-Biasing Magnet (Externally applied for ferromagnetic target) IC North Pole South Pole N NN S NS S S N NN S NS S S Rotation from pin 1 to pin 2 Pin 1 Pin 2 Branded Face of PackageRotatin (Ring magnet or ferromagnetic) (Ring magnet or ferromagnetic) g Target Rotation from pin 2 to pin 1 Pin 1 Pin 2 Branded Face of PackageRotating Target Table 1: Output Polarity when a South Pole Passes the Package Face in the Indicated Rotation Direction Rotation Direction Part Type A19200LUBx-H A19200LUBx-L Pin 1 → Pin 2 ICC(HIGH) ICC(LOW) Pin 2 → Pin 1 ICC(LOW) ICC(HIGH)
ASIL-Compliant Wheel Speed Sensor ICA19200 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com BOP(#1) BOP(#2) BRP(#1) Device Orientation to Target IC (Pin 1 Side)(Pin 2 Side) 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) Element Pitch Speed E1E2 N IC Internal Differential Analog Signals, VPROC Device Output Signal BOP(#1) BOP(#2) BRP(#1) IC (Pin 1 Side)(Pin 2 Side) Element Pitch (Top View of Package Case)E1E2 Device Orientation to Target Package Case Branded Face External Back-Biasing Magnet Speed Channel Element Pitch Mechanical Position (Target moves past device pin 1 to pin 2) Target (Ferromagnetic) This tooth sensed earlier This tooth sensed later IC Internal Differential Analog Signals, VPROC Target Magnetic Profile South Pole North Pole Device Output Signal Figure 5: Basic Operation
ASIL-Compliant Wheel Speed Sensor ICA19200 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Figure 6: Output Protocol with ASIL Safety Current Normal Operation S N S N S N Error Example 1 Error Example 2 Magnetic Encoder Error ICC(HIGH) ICC(LOW) ICC(HIGH) ICC(LOW) ICC(HIGH) ICC(LOW) IFAULT IFAULT Error ASIL Safe State The A19200 sensor IC contains diagnostic circuitry that will continuously monitor occurrences of failure defects within the IC. Refer to Figure 6 for the ASIL output protocol. Refer to the Safety Manual for additional details.
ASIL-Compliant Wheel Speed Sensor ICA19200 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com 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 appli- cation. This section presents a procedure for correlating factors affecting operating TJ. (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, RθJC, 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 TJ, at PD. PD = 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 = 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 minimum-K PCB. Observe the worst-case ratings for the device, specifically: RθJA = 213°C/W, TJ(max) = 165°C, VCC(max) = 24 V , and ICC(max) = 16 mA. 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(max) = 70.4 mW ÷ 16.0 mA = 4.4 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 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
ASIL-Compliant Wheel Speed Sensor ICA19200 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Figure 7: Package UB, 2-Pin SIP For Reference Only –N ot for Tooling Use (Reference DWG-0000408, Rev. 4) Dimensions in millimeters – NOT TO SCALE Exact case and lead configuration at supplier discretion within limits shown 0.65 ±0.07 7° ×2 R0.20 (all edges) 4.00 +0.06 –0.05 10° ×4 1.50 ±0.05 Active Area Depth 0.38 ±0.03 4.00 +0.06 –0.07 Package Front and Rear Surface Finish Ra 0.4 to 0.56 (Charmilles 12 to 15) 18.00 ±0.10 45° 0.42 ±0.05 R0.20 (all corners)
0.30 REF
2.54 REF
1.80 ±0.10 1.00 ±0.05 0.25 +0.07 –0.03 Plating Included R0.12 (all edges) 1.50 ±0.05
0.38 REF
0.85 ±0.05 /uni23001.00 REF ×2 Ejector Pin R0.30 (all corners)
0.25 REF
3.35 ±0.10
7.37 REF ×4
/uni23002.00 REF Ejector Pin 0.10 +0.05 –0.10 DETAIL A
0.545 REF ×2
1.36 REF 0.15 REF
0.25 REF ×4
2.50 ±0.10 ×4 12.20 ±0.10
0.85 REF ×8
1.80 +0.06 –0.07 4.00 +0.06 –0.05 DETAIL A Molded Lead Bar for preventing damage to leads during shipment Gate and tie burr area Dambar Protrusion Removal ×8 1.75 1.125 1.54 Hall Element E1 (not to scale) Hall Element E2 (not to scale) Line 1 = Part Number (5 characters) Line 2 = Date Code (4 digits) Line 3 = Characters 5-8 of Assembly Lot Number Branding scale and appearance at supplier discretion Standard Branding Reference View Date Code Lot Number XXXXX PACKAGE OUTLINE DRAWING
ASIL-Compliant Wheel Speed Sensor ICA19200 Allegro MicroSystems Manchester, NH 03103-3353 U.S.A. www.allegromicro.com
Revision History
– September 29, 2020 Initial release
1 March 25, 2021 Updated “ASIL B” to “ASIL B(D)” (page 1)
2 April 11, 2022 Updated package drawing (page 11)
For the latest version of this document, visit our website: www.allegromicro.com Copyright 2022, Allegro MicroSystems. Allegro MicroSystems 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 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.