A1190, A1192 and A1193 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches Features and Benefits Description High speed, 4-phase chopper stabilization Low switchpoint drift throughout temperature range Low sensitivity to thermal and mechanical stresses On-chip protection Supply transient protection Reverse battery protection On-board voltage regulator 3.0 to 24 V operation Solid-state reliability Robust EMC and ESD performance Field programmable for optimized switchpoints Industry leading ISO 7637-2 performance through use of proprietary, 40-V clamping structure The A1190, A1192, and A1193 comprise a family of twowire, unipolar, Hall-effect switches, which can be trimmed by the user at end-of-line to optimize magnetic switchpoint accuracy in the application. These devices are produced on the Allegro(R) advanced BiCMOS wafer fabrication process, which implements a patented high frequency, 4-phase, chopper-stabilization technique. This technique achieves magnetic stability over the full operating temperature range, and eliminates offsets inherent in devices with a single Hall element that are exposed to harsh application environments. Packages Two-wire unipolar switches are particularly advantageous in cost-sensitive applications because they require one less wire for operation versus the more traditional open-collector output switches. Additionally, the system designer inherently gains diagnostics because there is always output current flowing, which should be in either of two narrow ranges. Any current level not within these ranges indicates a fault condition. The A119x family has a number of automotive applications. These include sensing seat track position, seat belt buckle presence, hood/trunk latching, and shift selector position. 3-pin ultramini SIP 1.5 mm x 4 mm x 3 mm (suffix UA) 3-pin SOT23-W 2 mm x 3 mm x 1 mm (suffix LH) All family members are offered in two package styles. The LH is a SOT-23W style, miniature, low profile package for surfacemount applications. The UA is a 3-pin, ultra-mini, single inline package (SIP) for through-hole mounting. Both packages are lead (Pb) free, with 100% matte tin leadframe plating. Approximate footprint Functional Block Diagram V+ VCC Regulator Program / Lock ICC Adjust To all subcircuits Amp Offset Adjust Sample and Hold 0.01 F Dynamic Offset Cancellation Clock/Logic Polarity Low-Pass Filter Schmitt Trigger GND UA package only A1190-DS, Rev. 3 GND Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 Selection Guide Part Number Packing1 Package Output (ICC) in South Polarity Field Supply Current at ICC(L) (mA) Low 2 to 5 A1190LLHLT-T2 LH (Surface mount) 7-in. reel, 3000 pieces/reel A1190LLHLX-T LH (Surface mount) 13-in. reel, 10 000 pieces/reel A1190LUA-T3 UA (Through hole) Bulk, 500 pieces/bag A1192LLHLT-T2 LH (Surface mount) 7-in. reel, 3000 pieces/reel A1192LLHLX-T LH (Surface mount) 13-in. reel, 10 000 pieces/reel A1192LUA-T3 UA (Through hole) Bulk, 500 pieces/bag A1193LLHLT-T2 LH (Surface mount) 7-in. reel, 3000 pieces/reel A1193LLHLX-T LH (Surface mount) 13-in. reel, 10 000 pieces/reel A1193LUA-T3 UA (Through hole) Bulk, 500 pieces/bag 1Contact Allegro(R) for additional packing options. 2These variants available only through authorized distributors. 3Contact factory for availability. Magnetic Operate Point, BOP (G) 10 to 200 Low 5 to 6.9 High Absolute Maximum Ratings Characteristic Symbol Forward Supply Voltage VCC Reverse Supply Voltage Notes Rating Unit 28 V VRCC -18 V Magnetic Flux Density B Unlimited G Operating Ambient Temperature TA -40 to 150 C Maximum Junction Temperature TJ(max) 165 C Tstg -65 to 170 C Storage Temperature Terminal List Table Pin-out Diagrams 3 Number NC 1 2 1 LH Package Range L 2 3 Name Function LH package UA package 1 VCC VCC Connects power supply to chip; used to apply programming signal 2 NC GND LH package: no connection UA package: ground terminal 3 GND GND Ground terminal UA Package Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 2 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 ELECTRICAL CHARACTERISTICS Valid at TA = -40C to 150C, TJ < TJ(max), CBYP = 0.01 F, through operating supply voltage range; unless otherwise noted Characteristics Symbol Supply Voltage1,2 VCC ICC(L) Supply Current ICC(H) Supply Zener Clamp Voltage VZ(sup) Min. Typ. Max. Operating, TJ 165 C Test Conditions 3.0 - 24 Unit V A1190 B > BOP 2.0 - 5.0 mA A1192 B > BOP 5 - 6.9 mA A1193 B < BRP 5 - 6.9 mA A1190, A1192 B < BRP 12 - 17 mA A1193 B > BOP 12 - 17 mA 28 - - V mA ICC = ICC(L)(max) + 3 mA, TA = 25C Supply Zener Clamp Current IZ(sup) VZ(sup) = 28 V - - ICC(L)(max) + 3 mA Reverse Supply Current IRCC VRCC = -18 V - - -1.6 mA di/dt No bypass capacitor, capacitance of probe CS = 20 pF - 90 - mA / s - 700 - kHz Output Slew Rate3 Chopping Frequency fC Power-Up Time2,4,5 ton Power-Up State6,7 POS A1190, A1192 CBYP = 0.01 F, B > BOP + 10 G - - 25 s A1193 CBYP = 0.01 F, B < BRP - 10 G - - 25 s - ICC(H) - - ton < ton(max) , VCC slew rate > 25 mV / s 1V CC represents the generated voltage between the VCC pin and the GND pin. 2The V CC slew rate must exceed 600 mV/ms from 0 to 3 V. A slower slew rate through this range can affect device performance. 3Measured without bypass capacitor between VCC pin and the GND pin. Use of a bypass capacitor results in slower current change. 4Power-Up Time is measured without and with a bypass capacitor of 0.01 F. Adding a larger bypass capacitor would cause longer Power-Up Time. 5Guaranteed by characterization and design. 6Power-Up State as defined is true only with a V CC slew rate of 25 mV / s or greater. 7For t > t and B on RP < B < BOP , Power-Up State is not defined. MAGNETIC CHARACTERISTICS1 Valid at TA = -40C to 150C, TJ TJ (max); unless otherwise noted Characteristics Min. Typ. Max. Unit2 - -14 10 G TA = 25C 10 - 200 G TA = 25C, VCC = 5 V 3 4.8 7.5 G Symbol Initial Operate Point Test Conditions BOP(init) Programmable Magnetic Operating Point BOP Average Magnetic Step Size3 STEPBOP Switchpoint Temperature Drift BOP - 20 - G Hysteresis BHYS 5 - 30 G 1Relative values of B use the algebraic convention, where positive values indicate south magnetic polarity, and negative values indicate north magnetic polarity; therefore greater B values indicate a stronger south polarity field (or a weaker north polarity field, if present). 21 G (gauss) = 0.1 mT (millitesla). 3STEP BOP is a calculated average from the cumulative programmed bits. PROGRAMMABLE PARAMETERS Name Functional Description Quantity of Bits BOP Trim Fine trim of Programmable Magnetic Operating Point 6 Programming Lock Lock access to programming 1 Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 3 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 Thermal Characteristics may require derating at maximum conditions, see application information Characteristic Symbol Test Conditions* RJA Package Thermal Resistance Value Unit Package LH, on 4-layer PCB based on JEDEC standard 228 C/W Package LH, on 2-layer PCB with 0.463 in.2 of copper area each side 110 C/W Package UA, on 1-layer PCB with copper limited to solder pads 165 C/W *Additional thermal information available on the Allegro website Maximum Allowable VCC (V) Power Derating Curve 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 VCC(max) 2-layer PCB, Package LH (RQJA = 110 C/W) 1-layer PCB, Package UA (RQJA = 165 C/W) 4-layer PCB, Package LH (RQJA = 228 C/W) 20 40 60 80 100 VCC(min) 120 140 160 180 Temperature (C) Power Dissipation, PD (m W) Power Dissipation versus Ambient Temperature 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 2l (R aye rP QJ C A = 11 B, P 0 ac 1-la C/ ka W (R yer PC ) ge L QJA = B H 165 , Pac C/ kage W) UA 4-lay er P (R CB, QJA = 228 Packag C/W e LH ) 20 40 60 80 100 120 Temperature (C) 140 160 180 Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 4 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 Characteristic Performance A1190 Average Supply Current (Low) versus Temperature A1190 Average Supply Current (Low) versus Supply Voltage 5.0 Supply Current, ICC(L) (mA) Supply Current, ICC(L) (mA) 5.0 4.5 4.0 VCC = 24 V 3.5 VCC = 3.0 V 3.0 2.5 2.0 -60 4.5 4.0 3.5 TA = -40C 3.0 2.5 2.0 -40 -20 0 20 40 60 80 100 120 140 2 160 6 A1192 and A1193 Average Supply Current (Low) versus Temperature 22 26 7.0 Supply Current, ICC(L) (mA) Supply Current, ICC(L) (mA) 18 A1192 and A1193 6.5 VCC = 24 V 6.0 VCC = 3.0 V 5.5 6.5 TA = 150C TA = -40C 6.0 TA = 25C 5.5 5.0 -40 -20 0 20 40 60 80 100 120 140 2 160 6 10 14 18 22 26 Supply Voltage, VCC (V) Ambient Temperature, TA (C) A1190/A1192/A1193 Average Supply Current (High) versus Temperature A1190/A1192/A1193 Average Supply Current (High) versus Supply Voltage 17 Supply Current, ICC(H) (mA) 17 Supply Current, ICC(H) (mA) 14 Average Supply Current (Low) versus Supply Voltage 7.0 16 VCC = 24 V 15 VCC = 3.0 V 14 13 12 -60 10 Supply Voltage, VCC (V) Ambient Temperature, TA (C) 5.0 -60 TA = 150C TA = 25C 16 -20 0 20 40 60 80 100 Ambient Temperature, TA (C) 120 140 160 TA = 150C TA = 25C 14 13 12 -40 TA = -40C 15 2 6 10 14 18 22 26 Supply Voltage, VCC (V) Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 5 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 A1190/A1192/A1193 Applied Flux Density at Switchpoint Hysteresis, BHYS (G) Average Switchpoint Hysteresis versus Temperature 30 25 20 15 VCC = 24 V VCC = 3.0 V 10 5 -60 -40 -20 0 20 40 60 80 100 120 140 160 Ambient Temperature, TA (C) A1190/A1192/A1193 Average Operate Point, BOP (G) Average Operate Point versus Code 160 Bit #5 140 120 100 80 Bit #4 60 BOP(init) 40 Bit #3 20 Bit #2 Bit #1 Bit #0 0 -20 0 4 8 12 16 20 24 28 32 36 Code Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 6 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 Functional Description The A1190 and A1192 output, ICC, switches low after the magnetic field at the Hall sensor IC exceeds the operate point threshold, BOP . When the magnetic field is reduced to below the release point threshold, BRP , the device output goes high. This is shown in figure 1, panel A. In the case of the reverse output polarity, as in the A1193, the device output switches high after the magnetic field at the Hall I+ sensor IC exceeds the operate point threshold, BOP . When the magnetic field is reduced to below the release point threshold, BRP, the device output goes low (panel B). The difference between the magnetic operate and release points is called the hysteresis of the device, BHYS . This built-in hysteresis allows clean switching of the output even in the presence of external mechanical vibration and electrical noise. I+ Switch to High ICC ICC ICC(H) Switch to Low Switch to Low Switch to High ICC(H) ICC(L) BRP B+ BHYS (A) Hysteresis curve for A1190 and A1192 B- BRP BOP B- ICC(L) 0 BOP 0 B+ BHYS (B) Hysteresis curve for A1193 Figure 1. Alternative switching behaviors are available in the A119x device family. On the horizontal axis, the B+ direction indicates increasing south polarity magnetic field strength, and the B- direction indicates decreasing south polarity field strength (including the case of increasing north polarity). Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 7 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 RSENSE V+ V+ VCC CBYP 0.01 F A119x GND VCC CBYP 0.01 F A119x GND GND A GND A A ECU RSENSE Package UA Only (A) Low side sensing (B) High side sensing Figure 2. Typical application circuits Chopper Stabilization Technique When using Hall-effect technology, a limiting factor for switchpoint accuracy is the small signal voltage developed across the Hall element. This voltage is disproportionally small relative to the offset that can be produced at the output of the Hall sensor IC. This makes it difficult to process the signal while maintaining an accurate, reliable output over the specified operating temperature and voltage ranges. Chopper stabilization is a unique approach used to minimize Hall offset on the chip. The patented Allegro technique, namely Dynamic Quadrature Offset Cancellation, removes key sources of the output drift induced by thermal and mechanical stresses. This offset reduction technique is based on a signal modulation-demodulation process. The undesired offset signal is separated from the magnetic fieldinduced signal in the frequency domain, through modulation. The subsequent demodulation acts as a modulation process for the offset, causing the magnetic field-induced signal to recover its original spectrum at base band, while the DC offset becomes a high-frequency signal. The magnetic-sourced signal then can pass through a low-pass filter, while the modulated DC offset is suppressed. The chopper stabilization technique uses a 350 kHz high frequency clock. For demodulation process, a sample and hold technique is used, where the sampling is performed at twice the chopper frequency. This high-frequency operation allows a greater sampling rate, which results in higher accuracy and faster signal-processing capability. This approach desensitizes the chip to the effects of thermal and mechanical stresses, and produces devices that have extremely stable quiescent Hall output voltages and precise recoverability after temperature cycling. This technique is made possible through the use of a BiCMOS process, which allows the use of low-offset, low-noise amplifiers in combination with high-density logic integration and sampleand-hold circuits. Regulator Hall Element Amp Sample and Hold Clock/Logic Low-Pass Filter Figure 3. Chopper stabilization circuit (Dynamic Quadrature Offset Cancellation) Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 8 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 Programming Guidelines Overview Programming is accomplished by sending a series of input voltage pulses serially through the VCC (supply) pin of the device. A unique combination of different voltage level pulses controls the internal programming logic of the device to select a desired programmable parameter and change its value. There are three voltage levels that must be taken into account when programming. These levels are referred to as high (VPH), mid (VPM), and low (VPL) (see figure 1 and table 1). Definition of Terms Register. The section of the programming logic that controls the choice of programmable modes and parameters. Bit Field. The internal fuses unique to each register, represented as a binary number. Changing the bit field selection in a particular register causes its programmable parameter to change, based on the internal programming logic. Key. A series of VPM voltage pulses used to select a register or mode. The A119x family features two programmable modes, Try mode and Blow mode. tACTIVE * In Try mode, programmable parameter values are set and measured. A parameter value is stored temporarily, and reset after cycling the supply voltage. Supply Voltage, VCC VPH * In Blow mode, the value of a programmable parameter may be permanently set by blowing solid-state fuses internal to the device. Device locking is also accomplished in this mode. The programming sequence is designed to help prevent the device from being programmed accidentally; for example, as a result of noise on the supply line. Although any programmable variable power supply can be used to generate the pulse waveforms, Allegro highly recommends using the Allegro Sensor IC Evaluation Kit, available on the Allegro website On-line Store. The manual for that kit is available for download free of charge, and provides additional information on programming these devices. tBLOW tPf tPr VPM VPL tLOW tLOW (Supply cycled) 0 Programming pulses Blow pulse Figure 4. Programming pulse definition (see table 1) Table 1. Programming Pulse Requirements, Protocol at TA = 25C (refer also to figure 4) Characteristic Symbol Programming Voltage VPM Notes Min. Typ. Max. Unit VPL Measured at the VCC pin. VPH Programming Current IPP tLOW Pulse Width Pulse Rise Time Pulse Fall Time Blow Pulse Slew Rate tPr = 11 s, VCC = 5 26 V, CBLOW = 0.1 F (min). Minimum supply current required to ensure proper fuse blowing. CBLOW must be connected between the VCC and GND pins during programming to provide the current necessary for fuse blowing. 4.5 5 5.5 V 12.5 - 14 V 21 - 27 V 175 - - mA Duration at VPL separating pulses at VPM or VPH. 20 - - s tACTIVE Duration of pulses at VPM or VPH for key/code selection. 20 - - s tBLOW Duration of pulse at VPH for fuse blowing. 90 100 - s tPr VPL to VPM , or VPL to VPH. 5 - 100 s tPf VPH to VPL , or VPM to VPL. 5 - 100 s 375 - - mV/ s SRBLOW Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 9 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 Code. The number used to identify the combination of fuses activated in a bit field, expressed as the decimal equivalent of the binary value. The LSB of a bit field is denoted as code 1, or bit 0. Programming Procedure Programming involves selection of a register, a mode, and then setting values for parameters in the register for evaluation or for fuse blowing. Figure 10 provides an overview state diagram. Addressing. Setting the bit field code in a selected register by serially applying a pulse train through the VCC pin of the device. Each parameter can be measured during the addressing process, but the internal fuses must be blown before the programming code (and parameter value) becomes permanent. Blow Pulse. A VPH pulse of sufficient duration to blow the addressed fuse. Register Selection Each programmable parameter can be accessed through a specific register. To select a register, a sequence of voltage pulses consisting of a VPH pulse, a series of VPM pulses, and a VPH pulse (with no VCC supply interruptions) must be applied serially to the VCC pin. The quantity of VPM pulses is called the key, and uniquely identifies each register. The pulses for selection of register key 1, is shown in figure 5. No VPM pulse is sent for key 0. The register selections are shown in table 2. Cycling the Supply. Powering-down, and then powering-up the supply voltage. Cycling the supply is used to clear the programming settings in Try mode. Mode Selection After register selection, the mode is selected, either Try or Blow mode. Try mode is selected by default. To select Blow mode, that mode selection key must be sent. Fuse Blowing. Applying a VPH pulse of sufficient duration to permanently set an addressed bit by blowing a fuse internal to the device. Once a bit (fuse) has been blown, it cannot be reset. Table 2. Programming Logic Table Register Key Name Bit Field Address (Code) Binary Format [MSB LSB] Decimal Equivalent Description Try Mode 0 1 7 BOP Trim Up Counting BOP Trim Down Counting Fuse Check 000000 0 Initial value (below minimum |BOP| ) (Try mode sequence starts with code 1); Code corresponds to bit field value (code 1 selects bit field value 000001) 111111 63 Maximum selectable value (above maximum |BOP| ) 111111 0 Initial value (above maximum |BOP| ) (Try mode sequence starts with code 1); Code is automatically inverted (code 1 selects bit field value 111110) 000000 63 Minimum selectable value (below minimum |BOP|) 000111 7 Check integrity of all fuse bits versus low threshold 0 0 11 1 1 15 Check integrity of all fuse bits versus high threshold Blow Mode 0 7 000000 0 Initial value (below minimum |BOP| ); (Only allows selection of 1 bit per sequence) 111111 63 Maximum selectable value (above maximum |BOP| ); (Only allows selection of 1 bit per sequence) 001000 8 Locks out access to all registers except Fuse Check BOP Trim Programming Lock Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 10 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 Try Mode In Try mode, bit field addressing is accomplished by applying a series of VPM pulses to the VCC pin of the device, as shown in figure 6. Each pulse increases the bit field value for the selected parameter, increasing by one on the falling edge of each additional VPM pulse. When addressing the bit field in Try mode, the quantity of VPM pulses is represented by a decimal number called the code. Addressing activates the corresponding fuse locations in the given bit field by increasing the binary value of an internal DAC, up to the maximum possible code. As the value of the bit field code increases, the value of the programmable parameter changes. Measurements can be taken after each VPM pulse to determine if the required result for the programmable parameter has been reached. Cycling the supply voltage resets all the locations in the bit field that have un-blown fuses to their initial states. When setting the BOP Trim parameter, as an aid to programming, values can be traversed from low to high, or from high to low. To accommodate this direction selection, the value of the bit field (and code) defaults to the value 1, on the falling edge of the final register selection VPH pulse (see figure 5). A complete example is provided in figure 11. Blow Mode After the required code is determined for a given parameter, its value can be set permanently by blowing individual fuses in the appropriate register bit field. Blowing is accomplished by selecting the register, then the Blow mode selection key, followed by the appropriate bit field address, and ending the sequence with the Blow pulse. The Blow mode selection key is a sequence of nine VPM pulses followed by one VPH pulse. A complete example is provided in figure 12. The Blow pulse consists of a VPH pulse of sufficient duration, tBLOW , to permanently set an addressed bit by blowing a fuse internal to the device. Due to power requirements, the fuse for each bit in the bit field must be blown individually. The A119x family built-in circuitry allows only one fuse at a time to be blown. During Blow mode, the bit field can be considered a "onehot" shift register. Table 3 relates the quantity of VPM pulses to the binary and decimal values for Blow mode bit field addressing. It should be noted that the simple relationship between the quantity of VPM pulses and the corresponding code is: 2n = Code, where n is the quantity of VPM pulses. The bit field has an initial state of decimal code 0 (binary 000000). Supply Voltage, VCC VPH Bit Field Selection Address Code Format (Decimal Equivalent) Code 5 VPM Code in Binary (Binary) 1 0 1 VPL Fuse Blowing Target Bits Bit 2 Bit 0 Key Fuse Blowing Address Code Format 0 Figure 7. Example of code 5 broken into its binary components VPL 0 Figure 6. Try mode bit field addressing pulses Code 2n - 1 Code 2n - 2 Code 3 Supply Voltage, VCC VPM Code 2 Figure 5. Register selection pulse sequence VPH Code 4 Code 1 (Decimal Equivalents) Table 3. Blow Mode Bit Field Addressing Quantity of VPM Pulses Binary Register Setting Equivalent Code 1 000001 1 2 000010 2 3 000100 4 4 001000 8 5 010000 16 6 100000 32 Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 11 A1190, A1192, and A1193 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches To correctly address the fuses to be blown, the code representing the required parameter value must be translated into a binary number. For example, as shown in figure 7, decimal code 5 is equivalent to the binary number 101. Therefore bit 2 must be addressed and blown, the device power supply cycled, and then bit 0 must be addressed and blown. The order of blowing bits, however, is not important. Blowing bit 0 first, and then bit 2 is acceptable. Note: After blowing, the programming is not reversible, even after cycling the supply power. Although a register bit field fuse cannot be reset after it is blown, additional bits within the same register can be blown at any time until the device is locked. For example, if bit 1 (binary 10) has been blown, it is still possible to blow bit 0. The end result would be binary 11 (decimal code 3). Locking the Device After the required code for each parameter is programmed, the device can be locked to prevent further programming of any parameters. To do so, perform the following steps: 1. Ensure that the CBLOW capacitor is mounted. 2. Select the Programming Lock register (key 7). 3. Select Blow mode (key 9). 4. Address bit 3 (001000) by sending four VPM pulses. 5. Send one Blow pulse, at IPP and SRBLOW, and sustain it for tBLOW. 6. Delay for a tLOW interval, then power-down. 7. Optionally check all fuses. Fuse Checking Incorporated in the A119x family is circuitry to simultaneously check the integrity of the fuse bits. The fuse checking feature is enabled by using the Fuse Check register (selection key 7), and while in Try mode, applying the codes shown in table 2. The register is only valid in Try mode and is available before or after the Programming Lock bit is set. Setting the fuse threshold high checks that all blown fuses are properly blown. Setting fuse threshold low checks all un-blown fuses are properly intact. The supply current increases by 250 A if a marginal fuse is detected. If all fuses are correctly blown or fully intact, there will be no change in supply current. Additional Guidelines The additional guidelines in this section should be followed to ensure the proper behavior of these devices: * A 0.1 F blowing capacitor, CBLOW, must be mounted between the VCC pin and the GND pin during programming, to ensure enough current is available to blow fuses. * The power supply used for programming must be capable of delivering at least VPH and 175 mA. * Be careful to observe the tLOW delay time before powering down the device after blowing each bit. * Lock the device (only after all other parameters have been programmed and validated) to prevent any further programming of the device. BOP Selection Selecting BOP should be done in two stages. First, Try mode should be used to adjust BOP and monitor the output state. Then the optimum BOP is set permanently using Blow mode. Use the BOP Trim Up Counting register to increase the BOP selection by one Magnetic Step Size, StepBOP , increment with each bit field pulse (see figure 8). Use the BOP Trim Down Counting register to decrease the BOP selection by one StepBOP with each bit field pulse (see figure 9). As an aid to programming, when using down-counting method, the A119x automatically inverts the bit field selection (code 0 in down-counting sets the bit field value 111111, and the actual bit field value decreases until code 63 sets bit field value 000000). Note that the release point, BRP , is a value below BOP . The difference is specified by the Hysteresis, BHYS , which is not programmable. Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 12 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 (Code 0, Bit value 111111 ) (Code 63, Bit value 111111 ) BOP |BOP(max)| BRP |BOP(min)| BHYS |BOP(max)| BOP BHYS BRP (Code 63, Bit value 000000) (Code 0, Bit value 000000 ) |BOP(min)| BOP BOP BHYS BRP 0 BRP 31 63 Try Mode, Bit Field Code Figure 8. BOP Selection Up Counting 0 31 BHYS 63 Try Mode, Bit Field Code Figure 9. BOP Selection Down Counting Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 13 A1190, A1192, and A1193 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches Figure 10. Programming state diagram Figure 11. Example of Try mode pulse sequence, Register Key = BOP selection down counting Figure 12. Example of Blow mode pulse sequence, Register Key = BOP selection bit field 2 (code 4) Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 14 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 Power Derating The device must be operated below the maximum junction temperature of the device, TJ(max). Under certain combinations of peak conditions, reliable operation may require derating supplied power or improving the heat dissipation properties of the application. This section presents a procedure for correlating factors affecting operating TJ. (Thermal data is also available on the Allegro MicroSystems Web site.) The Package Thermal Resistance, RJA, is a figure of merit summarizing the ability of the application and the device to dissipate heat from the junction (die), through all paths to the ambient air. Its primary component is the Effective Thermal Conductivity, K, of the printed circuit board, including adjacent devices and traces. Radiation from the die through the device case, RJC, is relatively small component of RJA. Ambient air temperature, TA, and air motion are significant external factors, damped by overmolding. The effect of varying power levels (Power Dissipation, PD), can be estimated. The following formulas represent the fundamental relationships used to estimate TJ, at PD. PD = VIN x IIN T = PD x RJA TJ = TA + T (1) (2) (3) Example: Reliability for VCC at TA = 150C, package UA, using a low-K PCB. Observe the worst-case ratings for the device, specifically: RJA = 165 C/W, TJ(max) = 165C, VCC(max) = 24 V, and ICC(max) = 17 mA. Calculate the maximum allowable power level, PD(max). First, invert equation 3: Tmax = TJ(max) - TA = 165 C - 150 C = 15 C This provides the allowable increase to TJ resulting from internal power dissipation. Then, invert equation 2: PD(max) = Tmax / RJA = 15C / 165 C/W = 91 mW Finally, invert equation 1 with respect to voltage: VCC(est) = PD(max) / ICC(max) = 91 mW / 17 mA = 5 V The result indicates that, at TA, the application and device can dissipate adequate amounts of heat at voltages VCC(est). Compare VCC(est) to VCC(max). If VCC(est) VCC(max), then reliable operation between VCC(est) and VCC(max) requires enhanced RJA. If VCC(est) VCC(max), then operation between VCC(est) and VCC(max) is reliable under these conditions. For example, given common conditions such as: TA= 25C, VCC = 12 V, ICC = 4 mA, and RJA = 140 C/W, then: PD = VCC x ICC = 12 V x 4 mA = 48 mW T = PD x RJA = 48 mW x 140 C/W = 7C TJ = TA + T = 25C + 7C = 32C A worst-case estimate, PD(max), represents the maximum allowable power level (VCC(max), ICC(max)), without exceeding TJ(max), at a selected RJA and TA. Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 15 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 Package LH, 3-Pin SOT23W +0.12 2.98 -0.08 1.49 D 44 3 A +0.020 0.180-0.053 0.96 D +0.10 2.90 -0.20 +0.19 1.91 -0.06 2.40 0.70 D 0.25 MIN 1.00 2 1 0.55 REF 0.25 BSC 0.95 Seating Plane Gauge Plane 8X 10 REF B PCB Layout Reference View Branded Face 1.00 0.13 +0.10 0.05 -0.05 0.95 BSC 0.40 0.10 For Reference Only; not for tooling use (reference DWG-2840) Dimensions in millimeters Dimensions exclusive of mold flash, gate burrs, and dambar protrusions Exact case and lead configuration at supplier discretion within limits shown A Active Area Depth, 0.28 mm REF B Reference land pattern layout All pads a minimum of 0.20 mm from all adjacent pads; adjust as necessary to meet application process requirements and PCB layout tolerances C Branding scale and appearance at supplier discretion D Hall element, not to scale NNT 1 C Standard Branding Reference View N = Last two digits of device part number T = Temperature code Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 16 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 Package UA, 3-Pin SIP +0.08 4.09 -0.05 45 B C E 2.05 NOM 1.52 0.05 10 1.44 NOM +0.08 3.02 -0.05 E Mold Ejector Pin Indent E Branded Face 45 NNN 0.79 REF A 1.02 MAX 1 D Standard Branding Reference View 1 2 = Supplier emblem N = Last three digits of device part number 3 +0.03 0.41 -0.06 14.99 0.25 For Reference Only; not for tooling use (reference DWG-9065) Dimensions in millimeters Dimensions exclusive of mold flash, gate burrs, and dambar protrusions Exact case and lead configuration at supplier discretion within limits shown +0.05 0.43 -0.07 A Dambar removal protrusion (6X) B Gate and tie bar burr area C Active Area Depth, 0.50 mm REF D Branding scale and appearance at supplier discretion E Hall element (not to scale) 1.27 NOM Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 17 Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches A1190, A1192, and A1193 Revision History Revision Revision Date Rev. 3 November 17, 2011 Description of Revision Update product selection and VCC , ton , tBLOW, and programming lock Copyright (c)2009-2011, Allegro MicroSystems, Inc. Allegro MicroSystems, Inc. reserves the right to make, from time to time, such departures from the detail specifications as may be required to permit improvements in the performance, reliability, or manufacturability of its products. Before placing an order, the user is cautioned to verify that the information being relied upon is current. Allegro's products are not to be used in life support devices or systems, if a failure of an Allegro product can reasonably be expected to cause the failure of that life support device or system, or to affect the safety or effectiveness of that device or system. The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. 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, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 18