A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator FEATURES AND BENEFITS • Proprietary segmented linear temperature compensation (TC) technology provides a typical accuracy of 1% over the full operating temperature range • 120 kHz nominal bandwidth achieved via proprietary packaging and chopper stabilization techniques • Over Field Fault signal with 6-bit programmable trigger levels, 2-bit programmable hysteresis, and latching or non-latching behavior • Over Field Fault response time < 4.5 μs (typ) • Extremely low noise and high resolution achieved via proprietary Hall element and low-noise amplifier circuits • Customer-programmable, high-resolution offset and sensitivity trim • Available in a 1-mm-thick SIP through-hole package • Factory-programmed sensitivity and quiescent output voltage TC with extremely stable temperature performance Continued on the next page… PACKAGE: DESCRIPTION The A1365 linear output Hall-effect sensor IC is specifically designed to provide a highly accurate output with improved resolution at high bandwidth for use in current-sensing applications. This device employs a segmented, linearly interpolated temperature compensation technology, which provides greater accuracy in sensitivity and offset voltage trimming and hence virtually zero temperature drift. This improvement greatly reduces the total error of the device across the operating temperature range. The highly programmable Over Field Fault signal (FAULT pin) can be used to detect a high magnetic field condition. Broken ground wire detection, undervoltage lockout for VCC below specification, and user-selectable output voltage clamps are also included, which are important for high reliability in automotive applications. The sensor accuracy and diagnostic capability make it ideally suited for automotive sockets such as HEV inverter and DC-to-DC converter applications. The A1365 Hall-effect sensor IC is extremely sensitive, fast, and temperature-stable. The accuracy and flexibility of this device is enhanced by user programmability, performed via the VCC supply and the output pins, which allows the device to be optimized in the application. 4-Pin SIP (suffix KT) This ratiometric Hall-effect sensor IC provides a voltage output that is proportional to the applied magnetic field. The quiescent output voltage is user-adjustable around 50% (bidirectional) of Continued on the next page… Not to scale V+ VCC (Programming) Programming Control Temperature Sensor CBYPASS EEPROM and Control Logic Sensitivity Control 6-Bit Programmable Window Comparator 6 bits VREF(High) – COMP_IN + 0.88 × VCC to 0.72 × VCC VREF(Low) Offset Control – Internal Pull-Up FAULT + Dynamic Offset Cancellation 0.12 × VCC to 0.28 × VCC Signal Recovery GND Functional Block Diagram A1365-GS-DS VOUT (Programming) A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator FEATURES AND BENEFITS (CONTINUED) • Selectable sensitivity range between 0.6 and 14 mV/G through use of coarse sensitivity program bits • Ratiometric sensitivity, quiescent voltage output, and clamps enable simple interface with application A-to-D converter (ADC) • Output voltage clamps provide short-circuit diagnostic capabilities • Open-circuit detection on ground pin (broken wire) • Undervoltage lockout for VCC below specification • Wide ambient temperature range: –40°C to 150°C DESCRIPTION (CONTINUED) the supply voltage, VCC . The device sensitivity is adjustable within the range of 0.6 to 14 mV/G. The A1365 incorporates a highly sensitive Hall element with a BiCMOS interface integrated circuit that employs temperaturecompensation circuitry to reduce the intrinsic sensitivity and offset drift of the Hall element. The IC also includes a small-signal high-gain amplifier, a clamped low-impedance output stage, and a proprietary high-bandwidth dynamic offset cancellation technique. Device specifications apply across an extended ambient temperature range: –40°C to 150°C. The A1365 sensor IC is provided in an extremely thin case (1 mm thick), 4-pin SIP (single inline package, suffix KT) that is lead (Pb) free, with 100% matte-tin leadframe plating. The thin package allows for better magnetic coupling because the smaller the air gap in the core is, the higher the coupling from current to magnetic field will be. Selection Guide Part Number Package Packing1 A1365LKTTN-1-T A1365LKTTN-2-T A1365LKTTN-5-T A1365LKTTN-10-T 4-pin SIP 4-pin SIP 4-pin SIP 4-pin SIP 4000 pieces per 13-in. reel 4000 pieces per 13-in. reel 4000 pieces per 13-in. reel 4000 pieces per 13-in. reel Sensitivity Range2 (mV/G) 0.6 to 1.3 1.3 to 2.9 2.9 to 6.4 6.4 to 14 1 Contact Allegro for additional packing options. recommends against changing Coarse Sensitivity settings when programming devices that will be used in production. Each A1365 has been factory temperature compensated at a specific sensitivity range, and changing the coarse bits setting could cause sensitivity drift through temperature range (ΔSensTC ) to exceed specified limits. 2 Allegro Specifications Absolute Maximum Ratings Thermal Characteristics Pinout Diagram and Terminal List Table Operating Characteristics Characteristic Performance Data Characteristic Definitions Functional Description Programming Sensitivity and Quiescent Voltage Output Coarse Sensitivity Memory-Locking Mechanisms Power-On Reset (POR) and Undervoltage Lockout (UVLO) Operation Detecting Broken Ground Wire Over Magnet Field Fault 3 3 3 4 5 9 13 19 19 19 19 20 21 22 Table of Contents Programming Serial Interface 24 Package Outline Drawing 31 Transaction Types Writing the Access Code Writing to Volatile Memory Writing to EEPROM Reading from EEPROM or Volatile Memory Error Checking Serial Interface Reference Serial Interface Message Structure VCC Levels During Manchester Communication Shadow Mode EEPROM Margining EEPROM Cell Organization EEPROM Error Checking and Correction (ECC) Detecting ECC Error 24 24 24 25 25 25 26 27 27 28 29 30 30 30 Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 2 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator SPECIFICATIONS Absolute Maximum Ratings Characteristic Symbol Notes Rating Unit Forward Supply Voltage VCC 6 V Reverse Supply Voltage VRCC –0.1 V Forward Output Voltage VOUT 25 V Reverse Output Voltage VROUT –0.1 V Forward Fault Voltage V F̄¯Ā¯Ū¯L̄¯T̄¯ 6 V Reverse Fault Voltage VR F̄¯Ā¯Ū¯L̄¯T̄¯ –0.1 V Output Source Current IOUT(source) VOUT to GND 2.8 mA IOUT(sink) VCC to VOUT 10 mA 100 cycles –40 to 150 ºC Tstg –65 to 165 ºC TJ(max) 165 ºC Output Sink Current Maximum Number of EEPROM Write Cycles EEPROMw(max) Operating Ambient Temperature TA Storage Temperature Maximum Junction Temperature L temperature range THERMAL CHARACTERISTICS: May require derating at maximum conditions; see application information Characteristic Symbol Package Thermal Resistance RθJA Test Conditions* On 1-layer PCB with exposed copper limited to solder pads Value Unit 174 ºC/W *Additional thermal information available on the Allegro website Power Dissipation versus Ambient Temperature 900 800 Power Dissipation, PD (mW) 700 600 (R 500 qJ A = 17 4 400 ºC /W ) 300 200 100 0 20 40 60 80 100 120 Temperature, TA (°C) 140 160 180 Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 3 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator A1365 Pinout Diagram and Terminal List Table Terminal List Table 1 Number Name 1 VCC Function Input Power Supply, use bypass capacitor to connect to ground; also used for programming 2 VOUT Output Signal, also used for programming 3 F̄¯Ā¯Ū¯L̄¯T̄¯ Over Field Fault Detection Flag 4 GND Ground 2 3 4 KT Package Pinout Diagram (Ejector pin mark on opposite side) Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 4 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator OPERATING CHARACTERISTICS: valid through the full operating temperature range TA, CBYPASS = 0.1 µF, and VCC = 5 V, unless otherwise specified Characteristic Symbol Test Conditions Min. Typ. Max. Unit1 Electrical Characteristics Supply Voltage VCC 4.5 5 5.5 V – 10 15 mA Supply Current ICC No load on VOUT, F̄¯Ā¯Ū¯L̄¯T̄¯ pin in highimpedance state, connected through a 10 kΩ resistor to VCC Power-On Time2 tPO TA = 25°C, CBYPASS = open, CL = 1 nF – 100 – µs Temperature Compensation Power-On Time2 tTC TA = 25°C, CBYPASS = open, CL = 1 nF – 90 – µs VUVLOH VCC rising and device function enabled – 4 4.3 V VUVLOL VCC falling and device function disabled 3.05 3.2 – V tUVLOE TA = 25°C, CBYPASS = open, CL = 1 nF, VCC fall time (5 V to 3 V) = 1.5 μs – 67 – µs tUVLOD TA = 25°C, CBYPASS = open, CL = 1 nF, VCC recover time (3 V to 5 V) = 1.5 μs – 6 – µs VPORH TA = 25°C, VCC rising – 2.9 – V VPORL TA = 25°C, VCC falling – 2.5 – V tPORR TA = 25°C, VCC rising Undervoltage Lockout (UVLO) Threshold2 UVLO Enable/Disable Delay Time2 Power-On Reset Voltage2 Power-On Reset Release Time2 Supply Zener Clamp Voltage Internal Bandwidth Vz BWi TA = 25°C, ICC = 30 mA – 85 – µs 6.5 7.5 – V Small signal –3 dB, CL = 1 nF, TA = 25°C – 120 – kHz fC TA = 25°C – 500 – kHz Propagation Delay Time2 tpd TA = 25°C, step magnetic field of 400 G, CL = 1 nF, Sens = 2 mV/G – 2.2 – µs Rise Time2 tr TA = 25°C, step magnetic field of 400 G, CL = 1 nF, Sens = 2 mV/G – 3.6 – µs Response Time2 tRESPONSE TA = 25°C, step magnetic field of 400 G, CL = 1 nF, Sens = 2 mV/G – 3.7 – µs Delay to Clamp2,4 tCLP TA = 25°C, step magnetic field from 160 to 240 G, CL = 1 nF, Sens = 10 mV/G – 10 – µs Chopping Frequency3 VOUT Characteristics Output Voltage Clamp5 Output Saturation Voltage2 Broken Wire Voltage2 Noise6 VCLP(HIGH) TA = 25°C, RL(PULLDWN) = 10 kΩ to GND 4.55 – 4.85 V VCLP(LOW) TA = 25°C, RL(PULLUP) = 10 kΩ to VCC 0.15 – 0.45 V VSAT(HIGH) TA = 25°C, RL(PULLDWN) = 10 kΩ to GND 4.8 – – V VSAT(LOW) TA = 25°C, RL(PULLDWN) = 10 kΩ to VCC – – 300 mV VBRK(HIGH) TA = 25°C, RL(PULLUP) = 10 kΩ to VCC – VCC – V VBRK(LOW) TA = 25°C, RL(PULLDWN) = 10 kΩ to GND – 200 – mV TA = 25°C, CL = 1 nF – 1.1 – mG/√(Hz) TA = 25°C, CL = 1 nF, Sens = 2 mV/G, bandwidth = BWi – 6.3 – mVp-p TA = 25°C, CL = 1 nF, Sens = 2 mV/G, bandwidth = BWi – 1 – mVRMS VN 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 5 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator OPERATING CHARACTERISTICS (continued): valid through the full operating temperature range TA, CBYPASS = 0.1 µF, and VCC = 5 V, unless otherwise specified Characteristic Symbol Test Conditions Min. Typ. Max. Unit1 VOUT Characteristics (continued) DC Output Resistance Output Load Resistance ROUT – < 10 – Ω RL(PULLUP) TA = 25°C VOUT to VCC 4.7 – – kΩ RL(PULLDWN) VOUT to GND 4.7 – – kΩ Output Load Capacitance7 CL VOUT to GND – 1 10 nF Output Slew Rate8 SR Sens = 2 mV/G, CL = 1 nF, TA = 25°C; step magnetic field of 400 G – 230 – V/ms – 6 – bit Over Field Fault Characteristics Fault Switchpoint Programming Bits FAULT_ THRESH Positive Field Fault Switchpoint Range9 VFPSP TA = 25°C, programmable using FAULT_ THRESH bits 0.72 × VCC – 0.88 × VCC V Negative Field Fault Switchpoint Range9 VFNSP TA = 25°C, programmable using FAULT_ THRESH bits 0.12 × VCC – 0.28 × VCC V – 16 – mV – 2 – bit TA = 25°C, FAULT_HYST = 0 (decimal), FAULT_THRESH = 0, no hysteresis – 0 – mV TA = 25°C, FAULT_HYST = 1 (decimal), FAULT_THRESH = 0, VCC = 5 V – 30 – mV TA = 25°C, FAULT_HYST = 2 (decimal), FAULT_THRESH = 0, VCC = 5 V – 60 – mV TA = 25°C, FAULT_HYST = 3 (decimal), FAULT_THRESH = 0, maximum hysteresis value, VCC = 5 V – 120 – mV – 1 – bit Fault Switchpoint Step Size Fault Hysteresis Programming Bits Fault Hysteresis Level Range9 Enable Latched Fault Bit StepFAULT TA = 25°C, Average Fault Switchpoint step size, VCC = 5 V FAULT_HYST VFHYST FAULT_ LATCH DC Fault Switchpoint Error ErrDFS FAULT_THRESH = 0 (decimal), RF(PULLUP) = 10 kΩ from F̄¯Ā¯Ū¯L̄¯T̄¯ to VCC; measured under DC conditions, VFHYST = 60 mV – ±40 – mV DC Fault Switchpoint Symmetry Error ErrDFSS FAULT_THRESH = 0 (decimal), RF(PULLUP) = 10 kΩ from F̄¯Ā¯Ū¯L̄¯T̄¯ to VCC; measured under DC conditions, VFHYST = 60 mV – ±60 – mV ¯Ā¯Ū¯L̄¯T̄¯ Pin Low Output Voltage F̄ V F̄¯Ā¯Ū¯L̄¯T̄¯L RF(PULLUP) = 10 kΩ from F̄¯Ā¯Ū¯L̄¯T̄¯ to VCC – – 0.3 V tTFR RF(PULLUP) = 10 kΩ from F̄¯Ā¯Ū¯L̄¯T̄¯ to VCC, CF = Open, FAULT_THRESH = 0, VOUT step from VOUT(Q) to VOUT = 1.3 × (VFPSP VOUT(Q)) + VOUT(Q) – 4.5 – µs tTFRL RF(PULLUP) = 10 kΩ from F̄¯Ā¯Ū¯L̄¯T̄¯ to VCC, CF = Open, FAULT_THRESH = 0, VFHYST = 0 mV, VOUT step from VOUT = 1.1 × (VFPSP - VOUT(Q)) + VOUT(Q) – 2.5 – µs Transient Fault Response Time10 Transient Fault Release Time 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 6 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator OPERATING CHARACTERISTICS (continued): valid through the full operating temperature range, TA, CBYPASS = 0.1 µF, and VCC = 5 V, unless otherwise specified Characteristic Symbol Test Conditions Min. Typ. Max. Unit1 Fault Characteristics (continued) Fault Delay Due to Load Capacitance tFDC RF(PULLUP) = 10 kΩ from F̄¯Ā¯Ū¯L̄¯T̄¯ to VCC – 0.5 – µs / nF External Pull-Up Supply Voltage VF(PULLUP) 1.65 VCC VCC V ¯Ā¯Ū¯L̄¯T̄¯ Pull-Up Resistor External F̄ RF(PULLUP) 4.7 – – kΩ CF – – 10 nF ¯Ā¯Ū¯L̄¯T̄¯ Pull-Up Resistor Internal F̄ RIF(PULLUP) – 10 – kΩ ¯Ā¯Ū¯L̄¯T̄¯ Pull-Up Current Internal F̄ IIF(PULLUP) – 40 – µA ¯Ā¯Ū¯L̄¯T̄¯ Capacitance External F̄ Quiescent Voltage Output (VOUT(Q))2 Initial Unprogrammed Quiescent Voltage Output2,11 VOUT(Q)init TA = 25°C 2.4 2.5 2.6 V Quiescent Voltage Output Programming Range2,5,12 VOUT(Q)PR TA = 25°C 2.3 – 2.7 V Quiescent Voltage Output Programming Bits13 QVO – 9 – bit 1.9 2.3 2.8 mV – ±0.5 × StepVOUT(Q) – mV Average Quiescent Voltage Output Programming Step Size2,14,15 StepVOUT(Q) Quiescent Voltage Output Programming Resolution2,16 ErrPGVOUT(Q) TA = 25°C TA = 25°C Sensitivity (Sens)2 Initial Unprogrammed Sensitivity11 Sensitivity Programming Range5,12 Coarse Sensitivity Programming Bits17 Fine Sensitivity Programming Bits13 Average Fine Sensitivity and Temperature Compensation Programming Step Size2,14,15 Sensitivity Programming Resolution2,16 Sensinit SENS_COARSE = 00, TA = 25°C – 1 – mV/G SENS_COARSE = 01, TA = 25°C – 2.2 – mV/G SENS_COARSE = 10, TA = 25°C – 4.7 – mV/G SENS_COARSE = 11, TA = 25°C – 9.6 – mV/G SENS_COARSE = 00, TA = 25°C 0.6 – 1.3 mV/G SENS_COARSE = 01, TA = 25°C 1.3 – 2.9 mV/G SENS_COARSE = 10, TA = 25°C 2.9 – 6.4 mV/G SENS_COARSE = 11, TA = 25°C 6.4 – 14 mV/G SENS_ COARSE – 2 – bit SENS_FINE – 9 – bit SENS_COARSE = 00, TA = 25°C 2.4 3.2 4.1 µV/G SENS_COARSE = 01, TA = 25°C 5 6.6 8.5 µV/G SensPR StepSENS ErrPGSENS SENS_COARSE = 10, TA = 25°C 11 14.2 18 µV/G SENS_COARSE = 11, TA = 25°C 22 29 38 µV/G TA = 25°C – ±0.5 × StepSENS – µV/G – 0 – %/°C Factory-Programmed Sensitivity Temperature Coefficient Sensitivity Temperature Coefficient2 TCSENS Sensitivity Drift Through Temperature Range2,12,18,23 ΔSensTC TA=150°C, TA= –40°C, calculated relative to 25°C TA = 25°C to 150°C –2.5 – 2.5 % TA = –40°C to 25°C –3 – 3 % 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 7 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator A1365 OPERATING CHARACTERISTICS (continued): valid through the full operating temperature range, TA, CBYPASS = 0.1 µF, and VCC = 5 V, unless otherwise specified Characteristic Symbol Test Conditions Min. Typ. Max. Unit1 – 0 – mV/°C –10 – 10 mV Factory-Programmed Quiescent Voltage Output Temperature Coefficient Quiescent Voltage Output Temperature Coefficient2 Quiescent Voltage Output Drift Through Temperature Range2,12,18 Average Quiescent Voltage Output Temperature Compensation Step Size TCQVO ΔVOUT(Q)TC TA = 150°C, TA = –40°C, calculated relative to 25°C SENS_COARSE = 00, SENS_COARSE = 01, or SENS_COARSE = 10, TA = 25°C to 150°C SENS_COARSE = 11, TA = 25°C to 150°C –15 – 15 mV TA = –40°C to 25°C –30 – 30 mV StepQVOTC – 2.3 – mV EELOCK – 1 – bit LinERR –1 < ±0.25 1 % SymERR –0.5 < ±0.25 0.5 % –0.3 0 0.3 % < ±0.5 1 % Lock Bit Programming EEPROM Lock Bit Error Components Linearity Sensitivity Error2,19 Symmetry Sensitivity Error2 Ratiometry Quiescent Voltage Output Error2,20 Ratiometry Sensitivity Error2,20 Ratiometry Clamp Error2,21 RatERRVOUT(Q) Relative to VCC = 5 V ±5% RatERRSens Relative to VCC = 5 V ±5% –1 RatERRCLP TA = 25ºC, Relative to VCC = 5 V ±5% – < ±1 – % Sensitivity Drift Due to Package Hysteresis2 ΔSensPKG TA = 25°C, after temperature cycling, 25°C to 150°C and back to 25°C – -1.25 ±1.25 – % Sensitivity Drift Over Lifetime22 ΔSensLIFE TA = 25°C, shift after AEC Q100 grade 0 qualification testing – ±1% – % 11 G (gauss) = 0.1 mT (millitesla). Characteristic Definitions section. 2 See 3 f varies up to approximately ±5% over the full operating ambient C 4 If the programmed Fault Switchpoint exceeds the clamp voltage, temperature range, TA. Fault operation will have priority over clamp operation. VOUT(Q) , VCLP(LOW) , and VCLP(HIGH) scale with VCC due to ratiometry. 6 Noise, measured in mV PP and in mVRMS , is dependent on the sensitivity of the device. 7 Output stability is maintained for capacitive loads as large as 10 nF. 8 High-to-low transition of output voltage is a function of external load components and device sensitivity. 9 Fault Switchpoint and Fault Hysteresis are ratiometric. 10 Refer to Fault Characteristics section for the impact of load circuit and different Fault switchpoint settings on Transient Fault Response Time. 11 Raw device characteristic values before any programming. 12 Exceeding the specified ranges will cause sensitivity and Quiescent Voltage Output drift through the temperature range to deteriorate beyond the specified values. 13 Refer to Functional Description section. 14 Step size is larger than required, in order to provide for manufacturing spread. See Characteristic Definitions section. 15 Non-ideal behavior in the programming DAC can cause the step size at each significant bit rollover code to be greater than twice the maximum specified value of StepVOUT(Q) or StepSENS. 16 Overall programming value accuracy. See Characteristic Definitions section. 17 Each A1365 part number is factory-programmed and temperature compensated at a different coarse sensitivity setting. Changing coarse bits setting could cause sensitivity drift through temperature range ,ΔSensTC , to exceed specified limits. 18 Allegro will be testing and temperature compensating each device at 150°C. Allegro will not be testing devices at –40°C. Temperature compensation codes will be applied based on characterization data. 19 Linearity applies to output voltage ranges of ±2 V from the quiescent output for bidirectional devices. 20 Percent change from actual value at V CC = 5 V, for a given temperature, through the supply voltage operating range. 21 Percent change from actual value at V CC = 5 V, TA = 25°C, through the supply voltage operating range. 22 Based on characterization data obtained during standardized stress test for Qualification of Integrated Circuits. Cannot be guaranteed. Drift is a function of customer application conditions. Contact Allegro MicroSystems for further information. 23 Includes sensitivity drift due to package hysteresis after exposing the sensor to a temperature of 150ºC for 60 seconds during test. 5 Sens, Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 8 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator CHARACTERISTIC PERFORMANCE DATA Response Time (tRESPONSE) 400 G Excitation Signal with 10% - 90% rise time = 1 µs Sensitivity = 2 mV/G, CBYPASS = 0.1 µF, CL = 1 nF Input = 400 G Excitation Signal 80% of Input Output (VOUT, mV) 80% of Output tRESPONSE = 3.64 µs C1 FLT DC1M C1 FLT DC1M 1.00 V/div -3.0100 V 3.0681 V 3.8212 V 200 mV/div -3.10600 V 2.49230 V 3.13220 V Timebase -6.96 µs Trigger C1 DC 2.00 µs/div Stop 830 mV 50.0 ks 2.5 GS/s Edge Positive X1 = 467.6 ns X = 3.6444 µs X2 = 4.1120 µs 1/X = 274.390 kHz 11/6/2013 10:23:51 AM Propagation Delay (tPD) 400 G Excitation Signal with 10% - 90% rise time = 1 µs Sensitivity = 2 mV/G, CBYPASS = 0.1 µF, CL = 1 nF Input = 400 G Excitation Signal Output (VOUT, mV) tPD = 2.1 µs 20% of Output 20% of Input C1 FLT DC1M C2 FLT DC1M 1.00 V/div -3.0100 V 767.5 V 3.7877 V 200 mV/div -3.10600 V 2.50227 V 2.65287 V Timebase -6.96 µs Trigger C1 DC 2.00 µs/div Stop 830 mV 50.0 ks 2.5 GS/s Edge Positive X = X1 = -33.2 ns 2.0216 µs X2 = 1.9884 µs 1/X = 494.66 kHz 11/6/2013 10:22:47 AM Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 9 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator Rise Time (tr) 400 G Excitation Signal with 10% - 90% rise time = 1 µs Sensitivity = 2 mV/G, CBYPASS = 0.1 µF, CL = 1 nF Output (VOUT, mV) Input = 400 G Excitation Signal 90% of Output tR = 3.15 µs 10% of Input C1 FLT DC1M C2 FLT DC1M 1.00 V/div -3.0100 V 3.7602 V 3.8268 V 200 mV/div -3.10600 V 2.57280 V 3.21215 V Timebase -6.96 µs Trigger C1 DC 2.00 µs/div Stop 830 mV 50.0 ks 2.5 GS/s Edge Positive X = X1 = 1.6316 µs 3.1448 µs X2 = 4.7764 µs 1/X = 317.99 kHz 11/6/2013 10:21:02 AM Power-On Time (tPO) 400 G Constant Excitation Signal with VCC 10% - 90% rise time = 1 µs Sensitivity = 2 mV/G, CBYPASS = Open, CL = 1 nF Supply (VCC, V) VCC(min) Output (VOUT, V) 90% of Output tPO = 97 µs C1 F BwL DC1M C2 F BwL DC1M 1.00 V/div 1.00 V/div -3.0000 V -3.0000 V 63.4 mV 4.5241 V 3.0335 V 4.9957 V 2.9701 V 471.6 mV y y Timebase -120 µs Trigger C1 DC 3.13 V 50.0 µs/div Stop Positive 10.0 ks 20 MS/s Edge X1 = 1.05 µs X = 96.75 µs X2 = 97.80 µs 1/X = 10.336 kHz Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 10 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator Temperature Compensation Power-On Time (tTC) 400G Constant Excitation Signal, with VCC 10%-90% rise time = 1.5 μs Sensitivity = 2mV/G, CBYPASS = Open, CL = 1 nF Supply (VCC, V) Output (VOUT, V) 90% of Temperature Compensated Output 90% of Output tTC = 89 µs Timebase -120 µs Trigger C1 DC 3.13 V 50.0 µs/div Stop Positive 10.0 ks 20 MS/s Edge X1 = 97.80 µs X = 88.45 µs X2 = 186.25 µs 1/X = 11.306 kHz C1 F BwL DC1M C2 F BwL DC1M 1.00 V/div 1.00 V/div -3.0000 V -3.0000 V 3.0335 V 4.9957 V 3.4127 V 5.0019 V 379.2 mV 6.2 mV y y UVLO Enable Time (tUVLOE) VCC 5 V - 3 V fall time = 1.5 µs Sensitivity = 2 mV/G, CBYPASS = Open, CL = 1 nF Supply (VCC, V) tUVLOE = 67 µs VUVLOL Output (VOUT, V) Output = 0 V C1 F BwL DC1M C2 F BwL DC1M 1.00 V/div 1.00 V/div -3.0000 V -3.0000 V 3.5134 V 2.6689 V 3.0227 V 12.7 mV -490.6 mV y -2.6561 V y -2.5628 ms Trigger C1 DC 3.54 V 20.0 µs/div Stop Positive 10.0 ks 50 MS/s Edge X = X1 = 2.50062 ms 66.66 µs X2 = 2.56728 ms 1/X = 15.002 kHz Tbase Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 11 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator UVLO Disable Time (tUVLOD) VCC 3.2 V - 5 V Recovery Time = 1.5 µs Sensitivity = 2 mV/G, CBYPASS = Open, CL = 1 nF Supply (VCC, V) VCC(min) tUVLOD = 6 µs Output (VOUT, V) 90% of Output C1 A F B DC1M C2 A F B DC1M 1.00 V/div 1.00 V/div -3.0000 V -3.0000 V 539 # 539 # 92.6 mV 4.5048 V 2.2821 V 5.0297 V y 2.1895 V 524.9 mV y Timebase -6.4 µs Trigger C1 DC 3.54 V 5.00 µs/div Stop Positive 10.0 ks 200 MS/s Edge X = 6.000 µs X1 = -2.285 µs X2 = 3.715 µs 1/X = 166.7 kHz Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 12 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator CHARACTERISTIC DEFINITIONS Power-On Time (tPO) When the supply is ramped to its operating voltage, the device requires a finite time to power its internal components before responding to an input magnetic field. Power-On Time (tPO ) is defined as: the time it takes for the output voltage to settle within ±10% of its steady-state value under an applied magnetic field, after the power supply has reached its minimum specified operating voltage (VCC(min)) as shown in Figure 1. V VCC VCC(typ) VOUT 90% VOUT VCC(min) t1 t2= time at which output voltage settles within ±10% of its steady-state value under an applied magnetic field After Power-On Time (tPO ) elapses, tTC is also required before a valid temperature compensated output. 0 Propagation Delay (tpd) (%) 90 The time interval between a) when the sensor IC reaches 10% of its final value, and b) when it reaches 90% of its final value (see Figure 2). Both tr and tRESPONSE are detrimentally affected by eddy current losses observed in the conductive IC ground plane. A large magnetic input step may cause the clamp to overshoot its steady-state value. The Delay to Clamp (tCLP ) is defined as: the time it takes for the output voltage to settle within steady-state clamp voltage ±1% of Clamp Voltage Dynamic Range, after initially passing through its steady-state voltage, as shown in Figure 4. Clamp Voltage Dynamic Range is defined as VCLP(HIGH) (min) – VCLP(LOW) (max). Applied Magnetic Field Transducer Output Rise Time, tr 20 10 0 Response Time (tRESPONSE) Delay to Clamp (tCLP ) +t Figure 1: Power-On Time Definition Rise Time (tr) The time interval between a) when the applied magnetic field reaches 80% of its final value, and b) when the sensor reaches 80% of its output corresponding to the applied magnetic field (see Figure 3). tPO t1= time at which power supply reaches minimum specified operating voltage Temperature Compensation Power-On Time (tTC ) The time interval between a) when the applied magnetic field reaches 20% of its final value, and b) when the output reaches 20% of its final value (see Figure 2). t2 Propagation Delay, tpd t Figure 2: Propagation Delay and Rise Time Definitions (%) 80 Applied Magnetic Field Transducer Output Response Time, tRESPONSE 0 t Figure 3: Response Time Definition Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 13 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator A1365 Quiescent Voltage Output (VOUT(Q)) In the quiescent state (no significant magnetic field: B = 0 G), the output (VOUT(Q) ) has a constant ratio to the supply voltage (VCC ) throughout the entire operating ranges of VCC and ambient temperature (TA) . Initial Unprogrammed Quiescent Voltage Output ( VOUT(Q)init ) Before any programming, the Quiescent Voltage Output (VOUT(Q)) has a nominal value of VCC / 2, as shown in Figure 5. Quiescent Voltage Output Programming Range ( VOUT(Q)PR ) The Quiescent Voltage Output (VOUT(Q) ) can be programmed within the Quiescent Voltage Output Range limits: VOUT(Q)PR(min) and VOUT(Q)PR(max). Exceeding the specified Quiescent Voltage Output Range will cause Quiescent Voltage Output Drift Through Temperature Range ΔVOUT(Q)TC to deteriorate beyond the specified values, as shown in Figure 5. Average Quiescent Voltage Output Programming Step Size (StepVOUT(Q)) The Average Quiescent Voltage Output Progamming Step Size (StepVOUT(Q) ) is determined using the following calculation: StepVOUT(Q) = VOUT(Q)maxcode – VOUT(Q)mincode 2n – 1 , where n is the number of available programming bits in the trim range, 9 bits, VOUT(Q)maxcode is at decimal code 255, and VOUT(Q)mincode is at decimal code 256. Quiescent Voltage Output Programming Resolution (ErrPGVOUT(Q) ) The programming resolution for any device is half of its programming step size. Therefore, the typical programming resolution will be: ErrPGVOUT(Q)(typ) = 0.5 × StepVOUT(Q)(typ) Device VOUT(Q) changes as temperature changes, with respect to its programmed Quiescent Voltage Output Temperature Coefficient, TCQVO . TCQVO is programmed at 150°C and is calculated relative to the nominal VOUT(Q) programming temperature of 25°C. TCQVO (mV/°C) is defined as: VOUT tCLP t1 VOUT(Q)EXPECTED(TA) = VOUT(Q)T1 + TCQVO(TA – T1) t2 t1= time at which output voltage initially reaches steady-state clamp voltage t2= time at which output voltage settles to steady-state clamp voltage ±1% of the clamp voltage dynamic range, where clamp voltage dynamic range = VCLP(HIGH)(min) – VCLP(LOW)(max) Note: Times apply to both high clamp (shown) and low clamp. 0 Figure 4: Delay to Clamp Definition (3) where T1 is the nominal VOUT(Q) programming temperature of 25°C, and T2 is the TCQVO programming temperature of 150°C. The expected VOUT(Q) through the full ambient temperature range (VOUT(Q)EXPECTED(TA) ) is defined as: Magnetic Input VCLP(HIGH) (2) Quiescent Voltage Output Temperature Coefficient (TCQVO) TCQVO = [VOUT(Q)T2 – VOUT(Q)T1][1/(T2 – T1)] V (1) t VOUT(Q)PR(min) value Distribution of values resulting from minimum programming code (QVO programming bits set to decimal code 256) VOUT(Q) Programming range (specified limits) Typical initial value before customer programming VOUT(Q)init (QVO programming bits set to code 0) (4) VOUT(Q)PR(max) value Distribution of values resulting from maximum programming code (QVO programming bits set to decimal code 255) Figure 5: Quiescent Voltage Output Range Definition Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 14 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator VOUT(Q)EXPECTED(TA) should be calculated using the actual measured values of VOUT(Q)T1 and TCQVO rather than programming target values. Quiescent Voltage Output Drift Through Temperature Range (ΔVOUT(Q)TC) Due to internal component tolerances and thermal considerations, the Quiescent Voltage Output (VOUT(Q)) may drift from its nominal value through the operating ambient temperature (TA ). The Quiescent Voltage Output Drift Through Temperature Range (ΔVOUT(Q)TC) is defined as: DVOUT(Q)TC = VOUT(Q)(TA) – VOUT(Q)EXPECTED(TA) (5) ∆VOUT(Q)TC should be calculated using the actual measured values of ∆VOUT(Q)(TA) and ∆VOUT(Q)EXPECTED(TA) rather than programming target values. Sensitivity (Sens) The presence of a south polarity magnetic field, perpendicular to the branded surface of the package face, increases the output voltage from its quiescent value toward the supply voltage rail. The amount of the output voltage increase is proportional to the magnitude of the magnetic field applied. Conversely, the application of a north polarity field decreases the output voltage from its quiescent value. This proportionality is specified as the magnetic sensitivity, Sens (mv/G), of the device, and it is defined as: Sens = VOUT(BPOS) – VOUT(BNEG) BPOS – BNEG , (6) where BPOS and BNEG are two magnetic fields with opposite polarities. Branded Face Mold Ejector Pin Indent Initial Unprogrammed Sensitivity ( Sensinit ) Before any programming, Sensitivity has a nominal value that depends on the SENS_COARSE bits setting. Each A1365 variant has a different SENS_COARSE setting. Sensitivity Programming Range (SensPR) The magnetic sensitivity (Sens) can be programmed around its initial value within the sensitivity range limits: SensPR(min) and SensPR(max). Exceeding the specified Sensitivity Range will cause Sensitivity Drift Through Temperature Range ΔSensTC to deteriorate beyond the specified values. Refer to the Quiescent Voltage Output Range section for a conceptual explanation of how value distributions and ranges are related. Average Fine Sensitivity Programming Step Size (StepSENS) Refer to the Average Quiescent Voltage Output Programming Step Size section for a conceptual explanation. Sensitivity Programming Resolution ( ErrPGSENS) Refer to the Quiescent Voltage Output Programming Resolution section for a conceptual explanation. Sensitivity Temperature Coefficient (TCSENS) Device sensitivity changes as temperature changes, with respect to its programmed sensitivity temperature coefficient, TCSENS . TCSENS is programmed at 150°C, and calculated relative to the nominal sensitivity programming temperature of 25°C. TCSENS (%/°C) is defined as: TCSENS = SensT2 – SensT1 1 × 100% T2–T1 SensT1 (7) where T1 is the nominal Sens programming temperature of 25°C, and T2 is the TCSENS programming temperature of 150°C. The expected value of Sens over the full ambient temperature range, SensEXPECTED(TA), is defined as: SensEXPECTED(TA) = SensT1 × 100% + Magnetic Flux Direction Causing the Output to Increase , TCSENS (TA –T1) 100 (8) SensEXPECTED(TA) should be calculated using the actual measured values of SensT1 rather than programming target values. Figure 6: Magnetic Flux Polarity Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 15 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator A1365 Sensitivity Drift Through Temperature Range (ΔSensTC ) Second-order-sensitivity temperature-coefficient effects cause the magnetic sensitivity, Sens, to drift from its expected value over the operating ambient temperature range (TA). The Sensitivity Drift Through Temperature Range (∆SensTC ) is defined as: ∆SensTC = SensTA – SensEXPECTED(TA) SensEXPECTED(TA) × 100% . (9) Sensitivity Drift Due to Package Hysteresis (ΔSensPKG ) Package stress and relaxation can cause the device sensitivity at TA = 25°C to change during and after temperature cycling. The sensitivity drift due to package hysteresis (∆SensPKG ) is defined as: ∆SensPKG = Sens(25°C)2 – Sens(25°C)1 × 100% Sens(25°C)1 , (10) where Sens(25°C)1 is the programmed value of sensitivity at TA = 25°C, and Sens(25°C)2 is the value of sensitivity at TA = 25°C, after temperature cycling TA up to 150°C and back to 25°C. Linearity Sensitivity Error (LinERR ) The A1365 is designed to provide a linear output in response to a ramping applied magnetic field. Consider two magnetic fields, B1 and B2. Ideally, the sensitivity of a device is the same for both fields, for a given supply voltage and temperature. Linearity error is present when there is a difference between the sensitivities measured at B1 and B2. Linearity Error Linearity error is calculated separately for the positive (LinERRPOS ) and negative (LinERRNEG ) applied magnetic fields. Linearity Error (%) is measured and defined as: SensBPOS2 × 100% LinERRPOS = 1– SensBPOS1 , SensBNEG2 × 100% LinERRNEG = 1– SensBNEG1 , |VOUT(Bx) – VOUT(Q)| Bx , Then: LinERR = max( LinERRPOS , LinERRNEG ) . (13) Symmetry Sensitivity Error (SymERR ) The magnetic sensitivity of an A1365 device is constant for any two applied magnetic fields of equal magnitude and opposite polarities. Symmetry Error, SymERR (%), is measured and defined as: SensBPOS SymERR = 1– SensBNEG × 100% , (14) where SensBx is as defined in equation 12, and BPOSx and BNEGx are positive and negative magnetic fields such that |BPOSx| = |BNEGx|. Ratiometry Error (RatERR ) The A1365 device features ratiometric output. This means that the Quiescent Voltage Output (VOUT(Q) ) magnetic sensitivity, Sens, and Output Voltage Clamp (VCLP(HIGH) and VCLP(LOW) ) are proportional to the Supply Voltage (VCC). In other words, when the supply voltage increases or decreases by a certain percentage, each characteristic also increases or decreases by the same percentage. Error is the difference between the measured change in the supply voltage relative to 5 V, and the measured change in each characteristic. The ratiometric error in Quiescent Voltage Output, RatERRVOUT(Q) (%), for a given supply voltage (VCC) is defined as: VOUT(Q)(VCC) / VOUT(Q)(5V) × 100% . (15) RatERRVOUT(Q) = 1– VCC / 5 V The ratiometric error in magnetic sensitivity, RatERRSens (%), for a given Supply Voltage (VCC ) is defined as: (11) where: SensBx = and BPOSx and BNEGx are positive and negative magnetic fields, with respect to the quiescent voltage output such that |BPOS2| = 2 × |BPOS1| and |BNEG2| = 2 × |BNEG1|. (12) Sens(VCC) / Sens(5V) × 100% . RatERRSens = 1– VCC / 5 V (16) The ratiometric error in the clamp voltages, RatERRCLP (%), for a given supply voltage (VCC) is defined as: Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 16 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator VCLP(VCC) / VCLP(5V) × 100% , RatERRCLP = 1– VCC / 5 V (17) where VCLP is either VCLP(HIGH) or VCLP(LOW). Power-On Reset Voltage (VPOR ) On power-up, to initialize to a known state and avoid current spikes, the A1365 is held in Reset state. The Reset signal is disabled when VCC reaches VUVLOH and time tPORR has elapsed, allowing the output voltage to go from a high-impedance state into normal operation. During power-down, the Reset signal is enabled when VCC reaches VPORL , causing the output voltage to go into a high-impedance state. (Note that a detailed description of POR and UVLO operation can be found in the Functional Description section). Power-On Reset Release Time (tPORR) When VCC rises to VPORH , the Power-On Reset Counter starts. The A1365 output voltage will transition from a high-impedance state to normal operation only when the Power-On Reset Counter has reached tPORR and VCC has exceeded VUVLOH . Undervoltage Lockout Threshold (VUVLO ) If VCC drops below VUVLOL, the output voltage will be pulled to GND. If VCC starts rising, the A1365 will come out of this lock state when VCC reaches VUVLOH . or to VBRK(LOW) if a load resistor is connected to GND. DC Fault Switchpoint Error (ErrDFS) The Over Field Fault Switchpoint is user-programmable with a step size of StepFAULT. DC Fault Switchpoint Error is a deviation from the user-programmed value that occurs over the operating temperature range. DC Fault Switchpoint Symmetry Error (ErrDFSS) Writing FLT_THRESH bits sets the DC Fault Switchpoint for positive and negative magnetic fields as follows: Positive Field Fault Switchpoint (VFPSP) = Xpos × VCC and Negative Field Fault Switchpoint (VFNSP) = Xneg × VCC where Xpos + Xneg = 1. For example, programming VFPSP = 0.8 × VCC should automatically set VFNSP = 0.2 × VCC. For a measured VFPSP ,the DC Fault Switchpoint Symmetry error is the delta between the expected VFNSP and the measured one. Transient Fault Response Time (tTFR) The time interval between a) when the input crosses the DC Fault Switchpoint and b) when the FAULT pin reaches 20% of its final value. DC Fault Switchpoint (%) VFAULT Applied magnetic Field UVLO Enable/Disable Delay Time (tUVLO ) When a falling VCC reaches VUVLOL , time tUVLOE is required to engage the Undervoltage Lockout state. When VCC rises above VUVLOH , time tUVLOD is required to disable UVLO and to have a valid output voltage. Output Saturation Voltage (VSAT ) When output voltage clamps are disabled, the output voltage can swing to a maximum of VSAT(HIGH) and to a minimum of VSAT(LOW) . Broken Wire Voltage (VBRK ) If the GND pin is disconnected (broken wire event), output voltage will go to VBRK(HIGH) if a load resistor is connected to VCC, Transducer Output 20 t Transient Fault Response Time (tTFR) Figure 7: Transient Fault Response Time (tTFR) Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 17 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator Transient Fault Release Time (tTFRL) As the Over Field Fault condition goes away, tTFRL is the time interval between a) when the recovering input crosses the DC Fault Switchpoint and when the FAULT pin reaches 80% of its final value. Note that the DC Fault Switchpoint will be impacted by the programmed Fault Hysteresis Level (VFHSYT). (%) 80 VFAULT DC Fault Switchpoint Transducer Output Applied Magnetic Field t Transient Fault Release Time (tTFRL) Figure 8: Transient Fault Release Time (tTFRL) Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 18 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator A1365 FUNCTIONAL DESCRIPTION Programming Sensitivity and Quiescent Voltage Output Memory-Locking Mechanisms Sensitivity and VOUT(Q) can be adjusted by programming SENS_FINE and QVO bits, as illustrated in Figures 7 and 8. The A1365 is equipped with two distinct memory-locking mechanisms: Users should not program sensitivity or VOUT(Q) beyond the maximum or minimum programming ranges specified in the Operating Characteristics table. Exceeding the specified limits will cause the sensitivity and VOUT(Q) drift over the temperature range (ΔSensTC and ΔVOUT(Q)TC ) to deteriorate beyond the specified values. Programming sensitivity might cause a small drift in VOUT(Q) . As a result, Allegro recommends programming sensitivity first, then VOUT(Q) . Coarse Sensitivity Each A1365 variant is programmed to a different coarse sensitivity setting. Devices are tested, and temperature compensation is factory-programmed under that specific coarse sensitivity setting. If the coarse sensitivity setting is changed, by programming SENS_COARSE bits, Allegro cannot guarantee the specified sensitivity drift through temperature range limits (ΔSensTC ). • Default Lock At power-up, all registers of the A1365 are locked by default. EEPROM and volatile memory cannot be read or written. To disable Default Lock, a specific 30-bit customer access code has to be written to address 0x24 within Access Code Timeout (tACC = 8 ms) from power-up. After doing so, registers can be accessed. If VCC is power-cycled, the Default Lock will automatically be re-enabled. This ensures that during normal operation, memory content will not be altered due to unwanted glitches on VCC or the output pin. • Lock Bit After EEPROM has been programmed by the user, the EELOCK bit can be set high and VCC power-cycled to permanently disable the ability to read or write any register. This will prevent the ability to disable Default Lock using the method described above. Note that after the EELOCK bit is set high and the VCC pin is power-cycled, you will not have the ability to clear the EELOCK bit or read/write any register. Quiescent Voltage Output, VOUT(Q) (mV) Sensitivity, Sens (mV/G) Max Specified VOUT(Q)PR Max Specified SensPR Specified Sensitivity Programming Range Mid Range Specified VOUT(Q) Programming Range Mid Range Min Specified VOUT(Q)PR Min Specified SensPR 0 255 256 511 SENS_FINE Code Figure 9: Device Sensitivity versus SENS_FINE Programmed Value 0 255 256 511 QVO Code Figure 10: Device VOUT(Q) versus QVO Programmed Value Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 19 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator A1365 Power-On Reset (POR) and Undervoltage Lockout (UVLO) Operation go to VCC / 2 after tUVLOD [4]. • VCC drops below VCC(min)= 4.5 V If VCC drops below VUVLOL [4', 5], the UVLO Enable Counter starts counting. If VCC is still below VUVLOL when the counter reaches tUVLOE, the UVLO function will be enabled and the ouput will be pulled near GND [6]. If VCC exceeds VUVLOL before the UVLO Enable Counter reaches 64 µs [5'] , the output will continue to be VCC / 2. The descriptions in this section assume: TA = 25°C, no output load (RL, CL ) , and no significant magnetic field is present. • Power-Up At power-up, as VCC ramps up, the output is in a high-impedance state. When VCC crosses VPORH (location [1] in Figure 11 and [1'] in Figure 12), the POR Release counter starts counting for tPORR. At this point, if VCC exceeds VUVLOH [2'], the output will go to VCC / 2 after tUVLOD [3']. If VCC does not exceed VUVLOH [2], the output will stay in the high-impedance state until VCC reaches VUVLOH [3] and then • Coming out of UVLO While UVLO is enabled [6] , if VCC exceeds VUVLOH [7] , UVLO will be disabled after tUVLOD , and the output will be VCC / 2 [8]. • Power-Down As VCC ramps down below VUVLOL [6’, 9], the VCC 1 2 3 6 5 9 7 10 11 8 4 5.0 VUVLOH VUVLOL VPORH VPORL tUVLOE tUVLOE GND Time VOUT Slope = VCC / 2 2.5 tPORR tUVLOD tUVLOD GND High Impedance High Impedance Time Figure 11: POR and UVLO Operation – Slow Rise Time Case VCC 5.0 VUVLOH 1’ 2’ 4’ 5’ 6’ 7’ 3’ VUVLOL VPORH VPORL < tUVLOE GND Time VOUT tPORR Slope = VCC / 2 < 64 µs Slope = VCC / 2 2.5 tUVLOD GND High Impedance Time High Impedance Figure 12: POR and UVLO Operation – Fast Rise Time Case Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 20 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator A1365 UVLO Enable Counter will start counting. If VCC is higher than VPORL when the counter reaches tUVLOE , the UVLO function will be enabled and the ouput will be pulled near GND [10]. The output will enter a high-impedance state as VCC goes below VPORL [11]. If VCC falls below VPORL before the UVLO Enable Couner reaches tUVLOE, the output will transition directly into a high-impedance state [7']. A1365 VCC VOUT VF(PULLUP) GND FAULT V+ RF(PULLUP) CF CL Detecting Broken Ground Wire (Optional) If the GND pin is disconnected, node A becoming open (see Figure 12), the VOUT pin will go to a high-impedance state. The output voltage will go to VBRK(HIGH) if a load resistor RL(PULLUP) is connected to VCC or to VBRK(LOW) if a load resistor RL(PULLDWN) is connected to GND. The device will not respond to any applied magnetic field. CBYPASS Figure 13: Typical Application Drawing If the ground wire is reconnected, the A1365 will resume normal operation. VCC VCC VCC RL(PULLUP) VOUT VCC VOUT VCC VF(PULLUP) VF(PULLUP) A1365 RF(PULLUP) A1365 GND GND A A Connecting VOUT to RL(PULLUP) RF(PULLUP) FAULT FAULT RL(PULLDWN) Connecting VOUT to RL(PULLDWN) Figure 14: Connections for Detecting Broken Ground Wire Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 21 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator Over Magnetic Field Fault The A1365 offers a 6-bit programmable Ratiometric Fault as well as a 2-bit programmable Ratiometric Fault Hysteresis. ¯ pin is in a high-impedance During normal operation, the F̄¯Ā¯Ū¯L̄¯T̄ state. The combination of an internal pull-up resistance with an ¯Ā¯Ū¯L̄¯T̄¯ pin to be pulled high. internal current source enables the F̄ After the F̄¯Ā¯Ū¯L̄¯T̄¯ pin reaches VSAT(HIGH) , the current source is shut down. Figure 17 illustrates the impact of programming 60 mV of Fault Hysteresis on the Fault Switchpoint: ¯L̄¯T̄¯ The user could install an external pull-up resistor on the F̄¯Ā¯Ū ¯ ¯ ¯ ¯ ¯ pin to reduce the amount of time required by the F̄ĀŪL̄T̄ pin to reach VSAT(HIGH) after a fault event passes. An external pull-up resistor can be connected to a voltage (VF(PULLUP)) different from VCC as long as it remains within the VF(PULLUP) limits. If VF(PULLUP) is less than VCC, the current provided by the internal current source, IIF(PULLUP), will flow through the external pull-up resistance causing a small voltage drop. • FAULT_THRESH = 0, setting Positive and Negative Field Fault Switchpoint (VFPSP, VFNSP) to the middle of their programmable range. • FAULT_HYST = 2, setting Fault Hysteresis Level to 60 mV. The Fault Switchpoint is not affected by the selected Fault Hysteresis Level. The speed and accuracy with which a fault is triggered are characterized by the Transient Fault Response Time (tTFR), the DC Fault Switchpoint Error ( errDFS), and the Fault Delay Due to Load Capacitance (tFDC). Fault Switchpoint (V) VFAULT (V) Max Specified Switchpoint 5.0 VFHYST Specified Fault Switchpoint Range Mid Range VFPSP 0.1 3940 Min Specified Switchpoint 0 31 32 63 4000 VOUT (mV) FLT_THRESH Figure 17: Fault Hysteresis Behavior at FAULT_ THRESH = 0, FAULT_HYST = 2 Figure 16: Fault Switchpoint Programming Profile A1365 VCC IIF(PULLUP) RIF(PULLUP) VCC VOUT V+ CL (Optional) GND VF(PULLUP) FAULT RF(PULLUP) CF CBYPASS Figure 18: Fault Functional Circuit Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 22 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator A Fault Overstep is defined as the amount by which the output voltage exceeds the delta between VOUT(Q) and the DC Fault Switchpoint (VFPSP and VFNSP ). The larger the overstep caused by an input magnetic field is, the faster tTFR will be. When VFPSP and VFNSP are programmed near their limits, the maximum Fault Overstep will be limited because VOUT will be reaching saturation levels (see Figure 19). 0.75 Faults can be latched by setting the FAULT_LATCH bit high. ¯L̄¯T̄¯ pin will be held low. To reset the After a fault occurs, the F̄¯Ā¯Ū ¯Ū¯L̄¯T̄¯ pin, the A1365 must be powered down. F̄¯Ā Over Magnetic Field Fault can be disabled by setting the FLT_DIS bit. 5.5 Transient Fault Response Time, tTFR (µs) 11 Worst Process Corner when VFNSP = 0.1 × VCC 9 Worst Process Corner when VFPSP = 0.9 × VCC 7 Worst Process Corner when VFNSP > 0.17 × VCC and VFPSP < 0.87 × VCC 5 Typical Process Corner when VFNSP > 0.2 × VCC and VFPSP < 0.8 × VCC 2 0 5 10 15 20 VFault Overstep (%) Figure 19: Transient Fault Response Time versus Fault Overstep Voltage at VCC = 5 V, CF = 0 F, RL = Open. Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 23 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator PROGRAMMING SERIAL INTERFACE The A1365 incorporates a serial interface that allows an external controller to read and write registers in the EEPROM and volatile memory. The A1365 uses a point-to-point communication protocol, based on Manchester encoding per G. E. Thomas (a rising edge indicates 0 and a falling edge indicates 1), with address and data transmitted MSB first. Transaction Types Each transaction is initiated by a command from the controller; the A1365 does not initiate any transactions. Three commands are recognized by the A1365: Write Access Code, Write, and Read. One response frame type is generated by the A1365, Read Acknowledge. If the command is Read, the A1365 responds by transmitting the requested data in a Read Acknowledge frame. If the command is any other type, the A1365 does not acknowledge. As shown in Figure 20, the A1365 receives all commands via the VCC pin. It responds to Read commands via the VOUT pin. This implementation of Manchester encoding requires the communication pulses be within a high (VMAN(H)) and low (VMAN(L)) range of voltages for the VCC line and the VOUT line. The Write command to EEPROM is supported by two high-voltage pulses on the VOUT line. Writing the Access Code In order for the external controller to write or read from the A1365 memory during the current session, it must establish serial communication with the A1365 by sending a Write command including the Access Code within Access Code Timeout (tACC ) from power-up. If this deadline is missed, all write and read access is disabled until the next power-up. Writing to Volatile Memory In order for the external controller to write to volatile memory, a Write command must be transmitted on the VCC pin. Successive Write commands to volatile memory must be separated by tWRITE . The required sequence is shown in Figure 21. VCC Previous Command Write to Register R# tWRITE Next Command tWRITE t Figure 21: Writing to Volatile Memory Write/Read Command – Manchester Code Controller VCC RF(PULLUP) High Voltage pulses to activate EEPROM cells VCC A1365 FAULT VOUT GND Read Acknowledge – Manchester Code Figure 20: Top-Level Programming Interface Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 24 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator A1365 Writing to EEPROM In order for the external controller to write to non-volatile EEPROM, a Write command must be transmitted on the VCC pin. The controller must also send two Programming pulses, long high-voltage strobes, via the VOUT pin. These strobes are detected internally, allowing the A1365 to boost the voltage on the EEPROM gates. The required sequence is shown in figures 22 and 23. To ensure EEPROM integrity over lifetime, EEPROM should not be exposed to more than 100 Write cycles. Reading from EEPROM or Volatile Memory In order for the external controller to read from EEPROM or volatile memory, a Read command must be transmitted on the VCC line. Within time tstart_read , the VOUT line will stop VCC VOUT Write to Register R# Normal Operation EEPROM Programming Pulses High Impedance responding to the magnetic field and the Read Acknowledge frame will be transmitted on the VOUT line. The Read Acknowledge frame contains Read data. After the Read Acknowledge frame has been received from the A1365, the VOUT line resumes normal operation after time tREAD . The required sequence is shown in Figure 24. Error Checking The serial interface uses a cyclic redundancy check (CRC) for data-bit error checking (synchronization bits are ignored during the check). The CRC algorithm is based on the polynomial g(x) = x3 + x + 1, and the calculation is represented graphically in Figure 25. The trailing 3 bits of a message frame comprise the CRC token. The CRC is initialized at 111. If the serial interface receives a command with a CRC error, the command is ignored. VOUT Normal Operation t t tsPULSE(E) tWRITE(E) Figure 22: Writing to EEPROM VCC Figure 23: EEPROM Programming Pulses Read from Register R# C0 VOUT Normal Operation Read Acknowledge R# Input Data C2 Normal Operation t tstart_read C1 1x 0 1x 1 0x 2 1x 3 = x3 + x + 1 tREAD Figure 24: Reading from EEPROM or Volatile Memory Figure 25: CRC Calculation Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 25 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator Serial Interface Reference Required timing parameters for successful serial communication with A1365 device are given in table below. Required Serial Interface Timing Parameters Characteristics Symbol Note Min. Typ. Max. Unit Input/Output Signal Timing Access Code Timeout tACC Customer Access Code should be fully entered in less than tACC , measured from when VCC crosses VUVLOH . – – 8 ms Bit Rate tBITR Defined by the input message bit rate sent from the external controller 32 – 80 kbps tBIT Bit Time Data bit pulse width at 70 kbps 13.6 14.3 15 µs Bit Time Error errTBIT Deviation in tBIT during one command frame –11 – + 11 % Volatile Memory Write Delay tWRITE Required delay from the trailing edge of certain Write command frames to the leading edge of a following command frame 2 × tBIT – – µs Required delay from the trailing edge of the second EEPROM Programming pulse to the leading edge of a following command frame 2 × tBIT – – µs tREAD Required delay from the trailing edge of a Read Acknowledge frame to the leading edge of a following command frame 2 × tBIT – – µs tstart_read Delay from the trailing edge of a Read command frame to the leading edge of the Read Acknowledge frame 25 μs – 0.25 × tBIT 50 μs –0.25 × tBIT 150 μs – 0.25 × tBIT µs tsPULSE(E) Delay from last edge of write command to start of EEPROM programming pulse 40 – – μs Non-Volatile Memory Write Delay Read Acknowledge Delay Read Delay tWRITE(E) EEPROM Programming Pulse EEPROM Programming Pulse Setup Time Input/Output Signal Voltage Applied to VCC line Manchester Code High Voltage VMAN(H) Manchester Code Low Voltage VMAN(L) Manchester Level to VCC Delay tMAN_VCC 5.1 – – V VCC – 0.2 V – – V Applied to VCC line – – 3.9 V Read from VOUT line – – 0.2 V – – 15 µs Read from VOUT line Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 26 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator A1365 Serial Interface Message Structure Read/Write The general format of a command message frame is shown in Figure 26. Note that, in the Manchester coding used, a bit value of one is indicated by a falling edge within the bit boundary, and a bit value of zero is indicated by a rising edge within the bit boundary. Memory Address Synchronize 0 0 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 MSB VCC Levels During Manchester Communication For all devices with UVLO functionality, after power-up, it is important that the VCC pin be held at VCC until the first Synchronization pulse of a read/write transaction is sent (see Figure 27). During the transaction, the VCC pin varies between VMAN(H) and VMAN(L) , but after the last CRC bit has been sent, the controller must bring the VCC pin back to the VCC level in less than tMAN_VCC . This is important in order to avoid triggering the UVLO functionality during EEPROM read/write. Data ... CRC 0/1 0/1 0/1 0/1 MSB 0 0 1 1 0 Manchester Code per G. E. Thomas Bit boundaries Figure 26: General Format for Serial Interface Commands Read/Write Memory Address Synchronize 0 0 0/1 0 0 Data CRC 0/1 VMAN(H) VCC(V) VMAN(L) 0V 1 0 tMAN_VCC Bit boundaries Figure 27: VCC Levels During Manchester Communication Serial Interface Command General Format Quantity of Bits Parameter Name Values 2 Synchronization 00 Used to identify the beginning of a serial interface command 0 [As required] Write operation 1 [As required] Read operation Description 1 Read/Write 6 Address 0/1 [Read/Write] Register address (volatile memory or EEPROM) 30 Data 0/1 24 data bits and 6 ECC bits 3 CRC 0/1 Incorrect value indicates errors Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 27 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator A1365 Read (Controller to A1365) Read/Write The fields for the Read command are: Memory Address Synchronize • Sync (2 zero bits) 0 • Read/Write (1 bit, must be 1 for read) 0 0 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 . . . MSB • Address (6 bits) (ADDR[5] is 0 for EEPROM, 1 for register) • CRC (3 bits) Figure 28 shows the sequence for a Read command. Read/Write 0 CRC 1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 MSB Figure 30: Write Sequence Write Access Code (Controller to A1365) The fields for the Access Code command are: • Address (6 bits) (Address 0X24 for Customer Access) Read/Write • Sync (2 zero bits) • Data (30 bits: [29:26] Don’t Care, [25:24] ECC Pass/Fail, [23:0] Data) • CRC (3 bits) Figure 29 shows the sequence for a Read Acknowledge. Refer to the Detecting ECC Error section for instructions on how to detect and ECC failure. Data (30 bits maximum) • Read/Write (1 bit, must be 0 for write) Figure 31 shows the sequence for an Access Code command. The fields for the data return frame are: 0 MSB • CRC (3 bits) Read Acknowledge (A1365 to Controller) 0 0/1 0/1 0/1 0/1 • Data (30 bits) (0x2781_1F77 for Customer Access) Figure 28: Read Sequence Synchronize CRC • Sync (2 zero bits) Memory Address Synchronize 0 Data (30 bits maximum) CRC 0/1 0/1 0/1 0/1 . . . 0/1 0/1 0/1 0/1 0/1 MSB 0 0 0 1 • Read/Write (1 bit, must be 0 for write) • Address (6 bits) (ADDR[5] is 0 for EEPROM, 1 for register; refer to the address map) • Data (30 bits: [29:24] Don’t Care, [23:0] Data) • CRC (3 bits) Figure 30 shows the sequence for a Write command. Bits [29:24] are Don’t Care because the A1365 automatically generates 6 ECC bits based on the content of bits [23:0]. These ECC bits will be stored in EEPROM at locations [29:24]. 0 1 0 0 0/1 0/1 0/1 . . . CRC 0/1 0/1 0/1 0/1 MSB Figure 31: Access Code Write Sequence The controller must open the serial communication with the A1365 device by sending an Access Code. It must be sent within Access Code Timeout (tACC ) from power-up or the device will be disabled for read and write access. Access Codes Information Name Write (Controller to A1365) • Sync (2 zero bits) 0 MSB Figure 29: Read Acknowledge Sequence The fields for the Write command are: Data (30 bits) Memory Address Synchronize Customer Serial Interface Format Register Address (Hex) Data (Hex) 0x24 0x2781_1F77 Shadow Mode For faster programming, Shadow Mode puts the sensor in a try mode where one can write to the EEPROM registers as if they are volatile registers. This is especially useful when searching for Sensitivity, QVO, and Over Field Fault codes. Once the desired codes are identified, the user should exit Shadow Mode and execute an EEPROM Write. If a power-cycle is executed during Shadow Mode, the registers will reset to their initial state. SHADOW_ENABLE bit should be set to enter Shadow Mode. Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 28 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator A1365 EEPROM Margining Allegro factory-tests the capacity of each EEPROM bit to retain a “0” or a “1” state. After the user has completed EEPROM programming, the two VREAD bits could be set to “01” to change the EEPROM margin setting. EEPROM registers that were written by the user should be read and compared to the user-programmed value. The procedure should be repeated using VREAD = “10”. It is not mandatory for the user to execute EEPROM Margining. Memory Address Map Register Name Address FAC_LOT_NUM WAFER_NUM Customer ReadOnly EEPROM 0x00* Bits r/w 16 Location 15:0 Factory Wafer (stores up to 64 wafers) r/w 6 21:16 SCRATCH Factory use only r/w 2 23:22 8 bits X die location (accommodates up to 256 die in X) r/w 8 7:0 8 bits Y die location (accommodates up to 256 die in Y) r/w 8 15:8 SCRATCH Factory use only r/w 8 23:16 SENS_FINE Sensitivity r/w 9 8:0 0x01* SENS_COARSE Coarse Sensitivity r/w 2 10:9 QVO Quiescent Output Voltage r/w 9 19:11 FACTORY_RES1 0x02 POL Factory use only r/w 1 20 Reverses output polarity r/w 1 21 r/w 1 22 w 1 23 CLAMP_EN Clamp Enable EELOCK EEPROM LOCK FLT_THRESH Sets the DC Fault Switchpoint, two’s complement DAC profile r/w 6 5:0 FLT_HYST Fault Hysteresis Adjust, [00] = 0 V, [01] = 30 mV, [10] = 60 mV, [11] = 120 mV r/w 2 7:6 Enables Fault Latch r/w 1 8 FLT_LATCH 0x03 FLT_DIS Disables Fault r/w 1 9 Misc(x) Reserved for factory use; do not change default state r/w 11 20:10 MISC3_1 Factory-reserved (unused) r/w 3 23:21 Customer-reserved r/w 24 23:0 Disable Analog Output Sets the output pin to a high-impedance state r/w 1 0 SHADOW_ENABLE Enables register shadowing to bypass shadowed EEPROM registers r/w 1 1 r 1 2 r/w 2 4:3 r 1 5 CUSTOMER_RES Volatile Memory Customer Debug Register Description X_DIE_LOC Y_DIE_LOC Customer R/W EEPROM r/w Factory Lot (uses 3rd to 7th digits of the lot number) 0x04* CUSTOMER_ACCESS Customer write access enabled Factory Reserved Reserved for factory use. Do not change default state. OVERF_FLT 0x10 0 = No Over Field Fault 1 = Over Field Fault occurred, clears on read Factory Reserved Reserved for factory use; do not change default state. r/w 2 8:7 VREAD Change EEPROM read voltage for margining; [00] = 1.2 V (default), [01] = 0 V, [10] = 4.3 V, [11] = undefined r/w 2 10:9 Reserved for factory use (unused) n/a 13 23:11 30 29:0 – ACCESS_CODE 0x24 Customer code (not addressable) *EEPROM registers or bits that are not shadowed. Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 29 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator EEPROM Cell Organization Programming coefficients are stored in non-volatile EEPROM, which is separate from the digital subsystem, and accessed by the digital subsystem EEPROM Controller module. The EEPROM is organized as 30-bit-wide words, each word is made up of 24 data bits and 6 ECC (Error Checking and Correction) check bits, stored as shown in figure below. EEPROM Bit 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 Contents C5 C4 C3 C2 C1 C0 D23 D22 D21 D20 D19 D18 D17 D16 D15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 External EEPROM Word Bit Sequence; C# – Check Bit, D# – Data Bit EEPROM Error Checking and Correction (ECC) Detecting ECC Error If an uncorrectable error has occurred, bits 25:24 are set to 10, the VOUT pin will go to a high-impedance state, and the device will not respond to the applied magnetic field. Output voltage will go to VBRK(HIGH) if a load resistor RL(PULLUP) is connected to VCC or to VBRK(LOW) if a load resistor RL(PULLDWN) is connected to GND. Hamming code methodology is implemented for EEPROM checking and correction. The device has ECC enabled after power-up. The device always returns 30 bits. The message received from controller is analyzed by the device EEPROM driver and ECC bits are added. The first 6 received bits from device to controller are dedicated to ECC. EEPROM ECC Errors Bits Name Description 29:26 – No meaning 00 = No error 25:24 ECC 01 = Error detected and message corrected 10 = Uncorrectable error 11 = No meaning 23:0 D[23:0] EEPROM data Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 30 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator A1365 PACKAGE OUTLINE DRAWING For Reference Only - Not for Tooling Use (Reference DWG-9202) Dimensions in millimeters - NOT TO SCALE Dimensions exclusive of mold flash, gate burs, and dambar protrusions Exact case and lead configuration at supplier discretion within limits shown B 10° 5.21 +0.08 –0.05 1.00 +0.08 –0.05 E 2.60 F 1.00 F Mold Ejector Pin Indent +0.08 3.43 –0.05 F 0.89 MAX 1 2 3 Branded Face 4 A 0.54 REF NNNN YYWW 0.41 +0.08 0.20 –0.05 +0.08 –0.05 D 12.14 ±0.05 1.27 NOM N = Device part number Y = Last two digits of year of manufacture W = Week of manufacture 0.54 REF 0.89 MAX 1.50 +0.08 –0.05 D +0.08 5.21 –0.05 Standard Branding Reference View A Dambar removal protrusion (16X) B Gate and tie burr area C Branding scale and appearance at supplier discretion D Thermoplastic Molded Lead Bar for alignment during shipment E Active Area Depth, 0.37 mm REF F Hall element, not to scale +0.08 1.00 –0.05 Figure 32: Package KT, 4-Pin SIP Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 31 A1365 Low-Noise, High-Precision, Programmable Linear Hall-Effect Sensor IC With High-Bandwidth (120 kHz) Analog Output and Integrated Fault Comparator Revision History Revision Current Revision Date – January 7, 2016 Description of Revision Initial release Copyright ©2016, 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. 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 32