A1121

A1120, A1121, A1122, and A1125 Chopper Stabilized Precision Hall Effect Switches Features and Benefits ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ Unipolar switchpoints Resistant to physical stress Superior temperature stability Output short-circuit protection Operation from unregulated supply Reverse battery protection Solid-state reliability Small package sizes Description The A1120, A1121, A1122, and A1125 Hall-effect, unipolar switches are extremely temperature-stable and stress-resistant sensor ICs, especially suited for operation over extended temperature ranges to 150°C. Superior high-temperature performance is made possible through dynamic offset cancellation, which reduces the residual offset voltage normally caused by device overmolding, temperature dependencies, and thermal stress. Each device includes on a single silicon chip a voltage regulator, Hall-voltage generator, small-signal amplifier, chopper stabilization, Schmitt trigger, and a short-circuit protected open-drain output to sink up to 25 mA. An on-board regulator permits operation with supply voltages of 3 to 24 V. The advantage of operating down to 3 V is that the device can be used in 3 V applications or with additional external resistance in series with the supply pin for greater protection against high voltage transient events. For the A1120, A1121, and A1122, a south pole of sufficient strength turns the output on. Removal of the magnetic field turns the output off. The A1125 is complementary, in that for these devices, a south pole turns the A1125 output off, and removal of the magnetic field turns the output on. Two package styles provide a magnetically optimized package for most applications. Package type LH is a modified SOT23W, surface mount package, while UA is a three-lead ultra-mini SIP for through-hole mounting. Each package type is lead (Pb) free (suffix, –T), with a 100% matte tin plated leadframe. Packages: 3-pin SOT23W (suffix LH) 3-pin SIP (suffix UA) Not to scale Functional Block Diagram VCC Regulator To All Subcircuits Amp Sample and Hold Dynamic Offset Cancellation Low-Pass Filter VOUT Control Current Limit GND A1120-DS, Rev. 12 A1120, A1121, A1122 and A1125 Chopper Stabilized Precision Hall Effect Switches Selection Guide Part Number A1120ELHLX-T A1120ELHLT-T2 A1120EUA-T A1120LLHLX-T A1120LLHLT-T2 A1120LUA-T A1121ELHLX-T A1121ELHLT-T2 A1121EUA-T A1121LLHLX-T A1121LLHLT-T2 A1121LUA-T A1122ELHLX-T A1122ELHLT-T2 A1122EUA-T A1122LLHLX-T A1122LLHLT-T2 A1122LUA-T A1125ELHLX-T A1125EUA-T A1125LLHLX-T A1125LUA-T *Contact Allegro 2Available Packing1 13-in. reel, 10000 pieces/reel 7-in. reel, 3000 pieces/reel Bulk, 500 pieces/bag 13-in. reel, 10000 pieces/reel 7-in. reel, 3000 pieces/reel Bulk, 500 pieces/bag 13-in. reel, 10000 pieces/reel 7-in. reel, 3000 pieces/reel Bulk, 500 pieces/bag 13-in. reel, 10000 pieces/reel 7-in. reel, 3000 pieces/reel Bulk, 500 pieces/bag 13-in. reel, 10000 pieces/reel 7-in. reel, 3000 pieces/reel Bulk, 500 pieces/bag 13-in. reel, 10000 pieces/reel 7-in. reel, 3000 pieces/reel Bulk, 500 pieces/bag 13-in. reel, 10000 pieces/reel Bulk, 500 pieces/bag 13-in. reel, 10000 pieces/reel Bulk, 500 pieces/bag Mounting 3-pin SOT23W surface mount 3-pin SOT23W surface mount 3-pin SIP through hole 3-pin SOT23W surface mount 3-pin SOT23W surface mount 3-pin SIP through hole 3-pin SOT23W surface mount 3-pin SOT23W surface mount 3-pin SIP through hole 3-pin SOT23W surface mount 3-pin SOT23W surface mount 3-pin SIP through hole 3-pin SOT23W surface mount 3-pin SOT23W surface mount 3-pin SIP through hole 3-pin SOT23W surface mount 3-pin SOT23W surface mount 3-pin SIP through hole 3-pin SOT23W surface mount 3-pin SIP through hole 3-pin SOT23W surface mount 3-pin SIP through hole Ambient, TA Switchpoints (Typ.) BOP BRP Output In South (Positive) Magnetic Field –40ºC to 85ºC 35 –40ºC to 150ºC 25 –40ºC to 85ºC 95 –40ºC to 150ºC 70 On (logic low) –40ºC to 85ºC 150 –40ºC to 150ºC 125 –40ºC to 85ºC 35 –40ºC to 150ºC 25 Off (logic high) for additional packing options. through authorized Allegro distributors only. Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 2 A1120, A1121, A1122 and A1125 Chopper Stabilized Precision Hall Effect Switches Absolute Maximum Ratings Characteristic Forward Supply Voltage Reverse Supply Voltage Output Off Voltage Continuous Output Current Reverse Output Current Operating Ambient Temperature Maximum Junction Temperature Storage Temperature Symbol VCC VRCC VOUT IOUT IROUT TA TJ(max) Tstg Range E Range L Notes Rating 26.5 –30 26 25 –50 –40 to 85 –40 to 150 165 –65 to 170 Units V V V mA mA ºC ºC ºC ºC Pin-out Diagrams GND 3 Package LH Package UA 1 VCC 2 VOUT 1 VCC 2 GND 3 VOUT Terminal List Name VCC VOUT GND Description Connects power supply to chip Output from circuit Ground Number Package LH Package UA 1 1 2 3 3 2 Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 3 A1120, A1121, A1122 and A1125 Chopper Stabilized Precision Hall Effect Switches ELECTRICAL CHARACTERISTICS Valid valid over full operating voltage and ambient temperature ranges; unless otherwise noted Characteristics Electrical Characteristics Forward Supply Voltage VCC IOUTOFF Operating, TJ < 165°C A1120, A1121, A1122 A1125 A1120, A1121, A1122 A1125 A1120, A1121, A1122 A1125 Power-On Time3 Chopping Frequency Output Rise Time3,4 Output Fall Time3,4 tPO fC tr tf RL = 820 Ω, CS = 20 pF RL = 820 Ω, CS = 20 pF A1120, A1121, A1122 A1125 A1120, A1121, A1122 A1125 Reverse Supply Current Supply Zener Clamp Voltage Zener Impedance Magnetic Characteristics A1120 Operate Point BOP A1121 A1122 A1125 A1120 Release Point BRP A1121 A1122 A1125 A1120, A1125 A1121, A1122 (BOP – BRP) – 50 120 – 5 40 110 5 – 10 35 95 150 35 25 70 125 25 10 25 50 135 200 50 – 110 190 – – 42 G G G G G G G G G G IRCC VZ IZ VCC = 12 V, B > BOP VCC = 12 V, B < BRP VCC = 12 V, B < BRP VCC = 12 V, B > BOP VOUT = 24 V, B < BRP VOUT = 24 V, B > BOP IOUT = 20 mA, B > BOP IOUT = 20 mA, B < BRP B > BOP B < BRP 3 – – – – 30 30 – – – – – – – – – 28 – – – – 185 185 – – – 800 0.2 0.1 – – – – – – 50 24 10 10 500 500 60 60 25 – 2 2 4 4 4 4 –5 – – V μA μA mV mV mA mA μs kHz μs μs mA mA mA mA mA V Ω Symbol Test Conditions Min. Typ.1 Max. Unit2 Output Leakage Current Output Saturation Voltage VOUT(SAT) Output Current Limit IOM VCC > 3.0 V, B < BRP(min) – 10 G, B > BOP(max) + 10 G ICC(ON) Supply Current ICC(OFF) VRCC = –30 V ICC = 5 mA; TA = 25°C ICC = 5 mA; TA = 25°C Hysteresis BHYS 1Typical 21 data are are at TA = 25°C and VCC = 12 V, and are for initial design estimations only. G (gauss) = 0.1 mT (millitesla). 3Guaranteed by device design and characterization. 4C = oscilloscope probe capacitance. S Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 4 A1120, A1121, A1122 and A1125 Chopper Stabilized Precision Hall Effect Switches THERMAL CHARACTERISTICS may require derating at maximum conditions, see application information Characteristic Symbol Test Conditions Package LH, 1-layer PCB with copper limited to solder pads Package Thermal Resistance RθJA Package LH, 2-layer PCB with 0.463 in.2 of copper area each side connected by thermal vias Package UA, 1-layer PCB with copper limited to solder pads Value Units 228 110 165 ºC/W ºC/W ºC/W 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 20 40 Power Derating Curve TJ(max) = 165ºC; ICC = ICC(max) VCC(max) Maximum Allowable VCC (V) Package LH, 2-layer PCB (R JA = 110 ºC/W) Package UA, 1-layer PCB (R JA = 165 ºC/W) Package LH, 1-layer PCB (R JA = 228 ºC/W) VCC(min) 60 80 100 120 140 160 180 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 20 Power Dissipation, PD (mW) Pa (R cka ge JA = 1 LH 10 , 2Pac ºC lay /W er (R kage PC ) UA JA = B 165 , 1-la yer ºC/ W) PC B Pac k (R age LH ,1 JA = 2 28 º -layer PCB C/W ) 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 5 A1120, A1121, A1122 and A1125 Chopper Stabilized Precision Hall Effect Switches Characteristic Performance A1120, A1121, and A1125 Electrical Characteristics Average Supply Current (On) versus Ambient Temperature 6.0 5.5 5.0 4.5 Average Supply Current (On) versus Average Supply Voltage 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 2 6 10 14 18 22 26 ICC(av) (mA) 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 - 60 - 40 - 20 0 20 40 60 80 100 120 140 160 VCC (V) 3.0 12 24 ICC(av) (mA) TA (°C) –40 25 150 TA (°C) VCC (V) Average Supply Current (Off) versus Ambient Temperature 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 - 60 - 40 - 20 0 20 40 60 80 100 120 140 160 Average Supply Current (Off) versus Average Supply Voltage 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 2 6 10 14 18 22 26 ICC(av) (mA) ICC(av) (mA) VCC (V) 3.0 12 24 TA (°C) –40 25 150 TA (°C) VCC (V) Average Output Saturation Voltage versus Ambient Temperature 300 250 200 150 100 50 0 - 60 - 40 - 20 0 20 40 60 80 100 120 140 160 Average Output Saturation Voltage versus Supply Voltage 300 250 200 150 100 50 0 2 6 10 14 18 22 26 VOUT(sat) (V) VCC (V) 3.0 3.8 4.2 12 24 VOUT(sat) (V) TA (°C) –40 25 150 TA (°C) VCC (V) Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 6 A1120, A1121, A1122 and A1125 Chopper Stabilized Precision Hall Effect Switches A1120 and A1125 Magnetic Characteristics Average Operate Point versus Ambient Temperature 50 45 40 35 30 25 20 15 10 5 0 -60 -40 -20 0 20 40 60 80 100 120 140 160 50 45 40 35 Average Operate Point versus Average Supply Voltage BOP (G) BOP (G) VCC (V) 3.0 24 30 25 20 15 10 5 0 2 6 10 14 18 22 26 TA (°C) –40 25 150 TA (°C) VCC (V) Average Release Point versus Ambient Temperature 50 45 40 35 50 45 40 35 Average Release Point versus Average Supply Voltage BRP (G) BRP (G) 30 25 20 15 10 5 0 -60 -40 -20 0 20 40 60 80 100 120 140 160 VCC (V) 3.0 24 30 25 20 15 10 5 0 2 6 10 14 18 22 26 TA (°C) –40 25 150 TA (°C) VCC (V) Average Switchpoint Hysteresis versus Ambient Temperature 20 18 16 14 20 18 16 14 12 10 8 6 4 2 0 -60 -40 -20 0 20 40 60 80 100 120 140 160 Average Switchpoint Hysteresis versus Supply Voltage BHYS (G) 12 10 8 6 4 2 0 VCC (V) 3.0 24 BHYS (G) TA (°C) –40 25 150 2 6 10 14 18 22 26 TA (°C) VCC (V) Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 7 A1120, A1121, A1122 and A1125 Chopper Stabilized Precision Hall Effect Switches A1121 Magnetic Characteristics Operate Point versus Ambient Temperature 140 130 120 110 140 130 120 Operate Point versus Average Supply Voltage BOP (G) 100 90 80 70 60 50 - 60 - 40 - 20 0 20 40 60 80 100 120 140 160 BOP (G) VCC (V) 3.0 12 24 110 100 90 80 70 60 50 2 6 10 14 18 22 26 TA (°C) –40 25 150 TA (°C) VCC (V) Release Point versus Ambient Temperature 110 100 90 110 100 90 Release Point versus Average Supply Voltage BRP (G) BRP (G) 80 70 60 50 40 VCC (V) 3.0 12 24 80 70 60 50 40 TA (°C) –40 25 150 - 60 - 40 - 20 0 20 40 60 80 100 120 140 160 2 6 10 14 18 22 26 TA (°C) VCC (V) Switchpoint Hysteresis versus Ambient Temperature 40 35 40 35 Switchpoint Hysteresis versus Supply Voltage BHYS (G) VCC (V) 3.0 12 24 BHYS (G) 30 25 20 15 10 - 60 - 40 - 20 30 25 20 15 10 2 6 10 14 18 22 26 TA (°C) –40 25 150 0 20 40 60 80 100 120 140 160 TA (°C) VCC (V) Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 8 A1120, A1121, A1122 and A1125 Chopper Stabilized Precision Hall Effect Switches A1122 Magnetic Characteristics Operate Point versus Ambient Temperature 200 190 180 200 190 180 Operate Point versus Average Supply Voltage BOP (G) BOP (G) 170 160 150 140 130 120 - 60 - 40 - 20 VCC (V) 3.0 12 24 170 160 150 140 130 120 TA (°C) –40 25 150 0 20 40 60 80 100 120 140 160 2 6 10 14 18 22 26 TA (°C) VCC (V) Release Point versus Ambient Temperature 190 180 170 190 180 170 Release Point versus Average Supply Voltage BRP (G) 160 150 140 130 120 110 - 60 - 40 - 20 0 20 40 60 80 100 120 140 160 BRP (G) VCC (V) 3.0 12 24 160 150 140 130 120 110 2 6 10 14 18 22 26 TA (°C) –40 25 150 TA (°C) VCC (V) Switchpoint Hysteresis versus Ambient Temperature 40 35 40 35 Switchpoint Hysteresis versus Supply Voltage BHYS (G) VCC (V) 3.0 12 24 BHYS (G) 30 25 20 15 10 - 60 - 40 - 20 30 25 20 15 10 2 6 10 14 18 22 26 TA (°C) –40 25 150 0 20 40 60 80 100 120 140 160 TA (°C) VCC (V) Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 9 A1120, A1121, A1122 and A1125 Chopper Stabilized Precision Hall Effect Switches Functional Description Operation The output of the A1120, A1121, and A1122 devices switches low (turns on) when a magnetic field perpendicular to the Hall element exceeds the operate point threshold, BOP (see panel A of figure 1). When the magnetic field is reduced below the release point, BRP , the device output goes high (turns off). The output of the A1125 devices switches high (turns off) when a magnetic field perpendicular to the Hall element exceeds the operate point threshold, BOP (see panel B of figure 1). When the magnetic field is reduced below the release point, BRP , the device output goes low (turns on). After turn-on, the output voltage is VOUT(SAT) . The output transistor is capable of sinking current up to the short circuit current limit, IOM, which is a minimum of 30 mA. The difference in the magnetic operate and release points is the hysteresis, BHYS , of the device. This built-in hysteresis allows clean switching of the output even in the presence of external mechanical vibration and electrical noise. Powering-on the device in the hysteresis range (less than BOP and higher than BRP) will give an indeterminate output state. The correct state is attained after the first excursion beyond BOP or BRP . Applications It is strongly recommended that an external bypass capacitor be connected (in close proximity to the Hall element) between the supply and ground of the device to reduce external noise in the application. As is shown in panel B of figure 1, a 0.1 μF capacitor is typical. Extensive applications information for Hall effect devicers is available in: • Hall-Effect IC Applications Guide, Application Note 27701 • Guidelines for Designing Subassemblies Using Hall-Effect Devices, Application Note 27703.1 • Soldering Methods for Allegro’s Products – SMT and ThroughHole, Application Note 26009 All are provided in Allegro Electronic Data Book, AMS-702, and the Allegro Web site, www.allegromicro.com. V+ Switch to High Switch to Low VCC V+ Switch to High Switch to Low VS VCC VCC VOUT VOUT RL VOUT A112x CBYP 0.1 μF Output VOUT(SAT) 0 BRP BRP 0 B+ 0 0 BOP BHYS BOP BHYS VOUT(SAT) B+ GND (A) (B) (C) Figure 1. Device switching behavior. In panels A and B, on the horizontal axis, the B+ direction indicates increasing south polarity magnetic field strength. This behavior can be exhibited when using an electrical circuit such as that shown in panel C. Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 10 A1120, A1121, A1122 and A1125 Chopper Stabilized Precision Hall Effect Switches 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 element. 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 modulationdemodulation process. The undesired offset signal is separated from the magnetic field-induced 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 baseband, 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. This configuration is illustrated in figure 2. The chopper stabilization technique uses a 400 kHz high frequency clock. For demodulation process, a sample and hold technique is used, where the sampling is performed at twice the chopper frequency (800 kHz). 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 sample-and-hold circuits. The repeatability of magnetic field-induced switching is affected slightly by a chopper technique. However, the Allegro high frequency chopping approach minimizes the affect of jitter and makes it imperceptible in most applications. Applications that are more likely to be sensitive to such degradation are those requiring precise sensing of alternating magnetic fields; for example, speed sensing of ring-magnet targets. For such applications, Allegro recommends its digital device families with lower sensitivity to jitter. For more information on those devices, contact your Allegro sales representative. Regulator Clock/Logic Hall Element Amp Low-Pass Filter Figure 2. Model of chopper stabilization technique Sample and Hold Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 11 A1120, A1121, A1122 and A1125 Chopper Stabilized Precision Hall Effect Switches 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 website.) The Package Thermal Resistance, RJA, 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, RJC, is relatively small component of RJA. Ambient air temperature, TA, and air motion are significant external factors, damped by overmolding. The effect of varying power levels (Power Dissipation, PD), can be estimated. The following formulas represent the fundamental relationships used to estimate TJ, at PD. PD = VIN × IIN  T = PD × RJA TJ = TA + ΔT (1) (2) (3) A worst-case estimate, PD(max), represents the maximum allowable power level (VCC(max), ICC(max)), without exceeding TJ(max), at a selected RJA and TA. Example: Reliability for VCC at TA = 150°C, package LH, using a minimum-K PCB. Observe the worst-case ratings for the device, specifically: RJA = 228°C/W, TJ(max) = 165°C, VCC(max) = 24 V, and ICC(max) = 4 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 ÷ RJA = 15°C ÷ 228 °C/W = 66 mW Finally, invert equation 1 with respect to voltage: VCC(est) = PD(max) ÷ ICC(max) = 66 mW ÷ 4 mA = 16.5 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 RJA. 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= 25°C, VCC = 12 V, ICC = 1.6 mA, and RJA = 165 °C/W, then: PD = VCC × ICC = 12 V × 1.6 mA = 19 mW  T = PD × RJA = 19 mW × 165 °C/W = 3°C TJ = TA + T = 25°C + 3°C = 28°C Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 12 A1120, A1121, A1122 and A1125 Chopper Stabilized Precision Hall Effect Switches Package LH, 3-Pin (SOT-23W) +0.12 2.98 –0.08 1.49 D 3 A 4°±4° +0.020 0.180–0.053 0.96 D +0.10 2.90 –0.20 D +0.19 1.91 –0.06 0.25 MIN 1.00 1 2 0.55 REF 0.25 BSC Seating Plane Gauge Plane 8X 10° REF Branded Face 2.40 0.70 0.95 B PCB Layout Reference View 1.00 ±0.13 NNT +0.10 0.05 –0.05 0.95 BSC 0.40 ±0.10 1 C Standard Branding Reference View N = Last two digits of device part number T = Temperature code For Reference Only; not for tooling use (reference dwg. 802840) 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 B Active Area Depth, 0.28 mm REF 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 Branding scale and appearance at supplier discretion Hall element, not to scale C D Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 13 A1120, A1121, A1122 and A1125 Chopper Stabilized Precision Hall Effect Switches Package UA, 3-Pin SIP +0.08 4.09 –0.05 45° E B C 1.52 ±0.05 1.44 E Mold Ejector Pin Indent Branded Face 45° 1 D Standard Branding Reference View 0.79 REF A = Supplier emblem N = Last two digits of device part number T = Temperature code 2.04 +0.08 3.02 –0.05 E NNT 2.16 MAX 0.51 REF 1 2 3 For Reference Only; not for tooling use (reference DWG-9049) Dimensions in millimeters Dimensions exclusive of mold flash, gate burrs, and dambar protrusions Exact case and lead configuration at supplier discretion within limits shown 15.75 ±0.51 +0.03 0.41 –0.06 A Dambar removal protrusion (6X) B Gate burr area C Active Area Depth, 0.50 mm REF D E Branding scale and appearance at supplier discretion Hall element, not to scale +0.05 0.43 –0.07 1.27 NOM Copyright ©2009-2010, 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 14