A1201, A1202, A1203, and A1204 Continuous-Time Bipolar Switch Family GND Package LH, 3-pin Surface Mount 3 1 3 The A120x Hall-effect bipolar switches include the following on a single silicon chip: voltage regulator, Hall-voltage generator, small-signal amplifier, Schmitt trigger, and NMOS output transistor. The integrated voltage regulator permits operation from 3.8 to 24 V. The extensive on-board protection circuitry makes possible a ±30 V absolute maximum voltage rating for superior protection in automotive and motor commutation applications, without adding external components. All devices in the family are identical, except for magnetic switchpoints. 2 VCC VOUT 2 1 The Allegro® A1201, A1202, A1203 and A1204 Hall-effect bipolar switches are next-generation replacements and extension of the popular Allegro A3134, A3133, and A3132 bipolar switch product line. Overall, the A120x family, produced with BiCMOS technology, consists of continuous-time devices that feature fast poweron time and low-noise operation. Device programming is performed after packaging, to ensure increased switchpoint accuracy by eliminating offsets that can be induced by package stress. Unique Hall element geometries and low-offset amplifiers help to minimize noise and to reduce the residual offset voltage normally caused by device overmolding, temperature excursions, and thermal stress. The small geometries of the BiCMOS process allow these devices to be provided in ultrasmall packages. The package styles available provide magnetically optimized solutions for most applications. Package LH is a SOT23W, a miniature low-profile surface-mount package, while package UA is a three-lead ultramini SIP for through-hole mounting. Each package is lead (Pb) free, with 100% matte tin plated leadframes. Package UA, 3-pin SIP 2 3 VCC GND VOUT Features and Benefits 1 Continuous-time operation – Fast power-on time 1 2 3 – Low noise Stable operation over full operating temperature range Reverse battery protection ABSOLUTE MAXIMUM RATINGS Supply Voltage, VCC .......................................... 30 V Reverse-Supply Voltage, VRCC ........................ –30 V Output Off Voltage, VOUT .................................. 30 V Reverse-Output Voltage, VROUT ..................... –0.5 V Output Current, IOUTSINK ............................... 25 mA Magnetic Flux Density, B .........................Unlimited Operating Temperature Ambient, TA, Range E.................. –40ºC to 85ºC Ambient, TA, Range L................ –40ºC to 150ºC Maximum Junction, TJ(max)........................165ºC Storage Temperature, TS .................. –65ºC to 170ºC A1201-DS, Rev. 2 Solid-state reliability Factory-programmed at end-of-line for optimum performance Robust EMC performance High ESD rating Regulator stability without a bypass capacitor Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com A1201, A1202, A1203, and A1204 Continuous-Time Bipolar Switch Family Product Selection Guide Part Number Packing* Mounting Ambient, TA A1201ELHLT-T 7-in. reel, 3000 pieces/reel 3-pin SOT23W surface mount A1201EUA-T Bulk, 500 pieces/bag 3-pin SIP through hole A1201LLHLT-T 7-in. reel, 3000 pieces/reel 3-pin SOT23W surface mount A1201LUA-T Bulk, 500 pieces/bag 3-pin SIP through hole A1202ELHLT-T 7-in. reel, 3000 pieces/reel 3-pin SOT23W surface mount A1202EUA-T Bulk, 500 pieces/bag 3-pin SIP through hole A1202LLHLT-T 7-in. reel, 3000 pieces/reel 3-pin SOT23W surface mount A1202LUA-T Bulk, 500 pieces/bag 3-pin SIP through hole A1203ELHLT-T 7-in. reel, 3000 pieces/reel 3-pin SOT23W surface mount A1203EUA-T Bulk, 500 pieces/bag 3-pin SIP through hole A1203LLHLT-T 7-in. reel, 3000 pieces/reel 3-pin SOT23W surface mount A1203LUA-T Bulk, 500 pieces/bag 3-pin SIP through hole A1204ELHLT-T 7-in. reel, 3000 pieces/reel 3-pin SOT23W surface mount A1204EUA-T Bulk, 500 pieces/bag 3-pin SIP through hole A1204LLHLT-T 7-in. reel, 3000 pieces/reel 3-pin SOT23W surface mount A1204LUA-T Bulk, 500 pieces/bag 3-pin SIP through hole BRP (Min) BOP (Max) –50 50 –75 75 –95 95 –150 150 –40ºC to 85ºC –40ºC to 150ºC –40ºC to 85ºC –40ºC to 150ºC –40ºC to 85ºC –40ºC to 150ºC –40ºC to 85ºC –40ºC to 150ºC *Contact Allegro for additional packing options. Functional Block Diagram VCC To all subcircuits Regulator VOUT Amp Gain Offset Trim Control GND 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 2 A1201-DS, Rev. 2 Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com A1201, A1202, A1203, and A1204 Continuous-Time Bipolar Switch Family OPERATING CHARACTERISTICS over full operating voltage and ambient temperature ranges, unless otherwise noted Characteristic Symbol Test Conditions Min. Typ. Max. Units Electrical Characteristics Supply Voltage1 Output Leakage Current Output On Voltage Power-On Time2 Output Rise Time3 Output Fall Time3 Supply Current Reverse Battery Current VCC Operating, TJ < 165°C 3.8 – 24 V IOUTOFF VOUT = 24 V, B < BRP – – 10 µA VOUT(SAT) IOUT = 20 mA, B > BOP – 215 400 mV Slew rate (dVCC/dt) < 2.5 V/µs, B > BOP + 5 G or B < BRP – 5 G – – 4 µs tr VCC = 12 V, RLOAD = 820 Ω, CS = 12 pF – – 2 µs tf tPO VCC = 12 V, RLOAD = 820 Ω, CS = 12 pF – – 2 µs ICCON B > BOP – 3.8 7.5 mA ICCOFF B < BRP – 3.5 7.5 mA VRCC = –30 V – – –10 mA IRCC Supply Zener Clamp Voltage VZ ICC = 10.5 mA; TA = 25°C 32 – – V Supply Zener Current4 IZ VZ = 32 V; TA = 25°C – – 10.5 mA –40 15 50 G – 26 75 G Magnetic Characteristics5 A1201 Operate Point Release Point BOP BRP A1202 A1203 South pole adjacent to branded face of device – 26 95 G A1204 –100 42 150 G A1201 –50 –15 40 G –75 –26 – G –95 –26 – G –150 –40 100 G A1202 A1203 North pole adjacent to branded face of device A1204 Hysteresis BHYS A1201 5 30 55 G A1202 30 52 – G 30 52 – G 50 82 115 G A1203 BOP – BRP A1204 1 Maximum voltage must be adjusted for power dissipation and junction temperature, see Power Derating section. For VCC slew rates greater than 250 V/µs, and TA = 150°C, the Power-On Time can reach its maximum value. 3 C =oscilloscope probe capacitance. S 4 Maximum current limit is equal to the maximum I CC(max) + 22 mA. 5 Magnetic flux density, B, is indicated as a negative value for north-polarity magnetic fields, and as a positive value for south-polarity magnetic fields. This so-called algebraic convention supports arithmetic comparison of north and south polarity values, where the relative strength of the field is indicated by the absolute value of B, and the sign indicates the polarity of the field (for example, a –100 G field and a 100 G field have equivalent strength, but opposite polarity). 2 DEVICE QUALIFICATION PROGRAM Contact Allegro for information. EMC (Electromagnetic Compatibility) REQUIREMENTS Contact Allegro for information. 3 A1201-DS, Rev. 2 Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com A1201, A1202, A1203, and A1204 Continuous-Time Bipolar Switch Family THERMAL CHARACTERISTICS may require derating at maximum conditions, see application information Characteristic Symbol Test Conditions Package LH, minimum-K PCB (single layer, single-sided with copper limited to solder pads) Package LH, low-K PCB (single layer, double-sided with 0.926 in2 copper area) Package UA, minimum-K PCB (single layer, single-sided with copper limited to solder pads) RθJA Maximum Allowable VCC (V) Package Thermal Resistance Value Units 110 ºC/W 228 ºC/W 165 ºC/W Power Derating Curve TJ(max) = 165ºC; ICC = ICC(max) 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) Low-K PCB, Package LH (RθJA = 110 ºC/W) Minimum-K PCB, Package UA (RθJA = 165 ºC/W) Minimum-K PCB, Package LH (RθJA = 228 ºC/W) 20 40 60 80 100 120 VCC(min) 140 160 180 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 Lo (R w-K PC θJ A = 11 B, P 0 º ac Min C/ ka W ge (R imum ) LH KP θJA = 165 CB ºC/ , Pac W) kag eU A Min imu m-K (R P θJA = 228 CB, Pa ºC/W ckag e LH ) 20 40 60 80 100 120 Temperature (°C) 140 160 180 4 A1201-DS, Rev. 2 Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com A1201, A1202, A1203, and A1204 Continuous-Time Bipolar Switch Family Characteristic Data Supply Current (On) versus Ambient Temperature Supply Current (On) versus Supply Voltage (A1201/02/03/04) (A1201/02/03/04) 8.0 7.0 7.0 ICCON (mA) 6.0 VCC (V) 5.0 24 3.8 4.0 3.0 ICCON (mA) 8.0 TA (°C) –40 25 150 4.0 3.0 2.0 2.0 1.0 1.0 0 0 –50 0 50 TA (°C) 100 150 0 10 15 20 Supply Current (Off) versus Ambient Temperature Supply Current (Off) versus Supply Voltage (A1201/02/03/04) (A1201/02/03/04) 8.0 7.0 7.0 VCC (V) 5.0 24 3.8 4.0 3.0 ICCOFF (mA) 8.0 25 6.0 TA (°C) 5.0 –40 25 150 4.0 3.0 2.0 2.0 1.0 1.0 0 0 –50 0 50 TA (°C) 100 0 150 10 15 20 25 Output Voltage (On) versus Supply Voltage (A1201/02/03/04) 400 5 VCC (V) Output Voltage (On) versus Ambient Temperature (A1201/02/03/04) 400 350 350 300 300 250 VCC (V) 200 24 3.8 150 100 50 VOUT(SAT) (mV) VOUT(SAT) (mV) 5 VCC (V) 6.0 ICCOFF (mA) 6.0 5.0 TA (°C) 250 –40 25 150 200 150 100 50 0 0 –50 0 50 TA (°C) 100 150 0 5 10 15 20 25 VCC (V) 5 A1201-DS, Rev. 2 Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com A1201, A1202, A1203, and A1204 Continuous-Time Bipolar Switch Family Operate Point versus Ambient Temperature Operate Point versus Supply Voltage (A1201) (A1201) 50 50 40 40 30 30 20 VCC (V) 10 24 12 3.8 0 -10 BOP (G) BOP (G) 20 –40 25 150 0 -10 -20 -20 -30 -30 -40 TA (°C) 10 -40 -50 0 50 TA (°C) 100 150 0 15 20 25 Release Point versus Supply Voltage (A1201) (A1201) 40 40 30 30 20 20 10 10 VCC (V) 0 24 12 3.8 -10 -20 BRP (G) BRP (G) 10 VCC (V) Release Point versus Ambient Temperature TA (°C) 0 –40 25 150 -10 -20 -30 -30 -40 -40 -50 -50 -50 0 50 100 150 0 5 10 15 20 TA (°C) VCC (V) Hysteresis versus Ambient Temperature Hysteresis versus Supply Voltage (A1201) 55 25 (A1201) 55 50 50 45 45 40 40 VCC (V) 35 24 12 3.8 30 25 BHYS (G) BHYS (G) 5 –40 25 150 30 25 20 20 15 15 10 10 5 TA (°C) 35 5 -50 0 50 TA (°C) 100 150 0 5 10 15 20 25 VCC (V) 6 A1201-DS, Rev. 2 Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com A1201, A1202, A1203, and A1204 Continuous-Time Bipolar Switch Family Operate Point versus Ambient Temperature Operate Point versus Ambient Temperature (A1204) (A1202, A1203) 150 70 60 100 VCC (V) 40 24 12 3.8 30 A (°C) VT (V) CC 50 BOP (G) BOP (G) 50 –40 24 25 12 3.8 150 0 20 -50 10 0 -100 -50 0 50 TA (°C) 100 150 -50 0 100 150 Release Point versus Ambient Temperature Release Point versus Ambient Temperature (A1204) (A1202, A1203) 100 -5 -15 50 -25 VCC (V) -35 24 12 3.8 -45 A (°C) VT (V) CC 0 BRP (G) BRP (G) 50 TA (°C) –40 24 25 12 3.8 150 -50 -55 -100 -65 -75 -150 -50 0 50 TA (°C) 100 -50 150 Hysteresis versus Ambient Temperature 50 TA (°C) 100 150 Hysteresis versus Ambient Temperature (A1202, A1203) 80 (A1204) 130 75 120 70 65 110 VCC (V) 60 24 12 3.8 55 50 45 BHYS (G) BHYS (G) 0 VCC (V) 100 –40 24 12 25 3.8 150 90 80 70 40 60 35 30 50 -50 0 50 TA (°C) 100 150 -50 0 50 100 150 TA (°C) 7 A1201-DS, Rev. 2 Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com A1201, A1202, A1203, and A1204 Continuous-Time Bipolar Switch Family Functional Description Bipolar Device Switching The devices of the A120X family provide highly sensitive switching for applications using magnetic fields of alternating polarities, such as ring magnets. There are three switching modes for bipolar devices, referred to as latch, unipolar switch, and negative switch. Mode is determined by the switchpoint characteristics of the individual device. The characteristic hysteresis, BHYS , of the device, is the difference in the relative magnetic strength and polarity of the switchpoints of the device. (Note that, in the following descriptions, a negative magnetic value indicates a north polarity field, and a positive magnetic value indicates a south polarity field. For a given value of magnetic strength, BX , the values –BX and BX indicate two fields of equal strength, but opposite polarity. B = 0 indicates the absence of a magnetic field.) In contrast to latching, when a device exhibits unipolar switching, it only responds to a south magnetic field. The field must be of sufficient strength, > BOP , for the device to operate. When the field is reduced beyond the BRP level, the device switches back to the high state, as shown in panel B of figure 1. Devices exhibiting negative switch behavior operate in a similar but opposite manner. A north polarity field of sufficient strength, > BRP , (more north than BRP) is required for operation, although the result is that VOUT switches high, as shown in panel C. When VS VCC Bipolar devices typically behave as latches. In this mode, magnetic fields of opposite polarity and equivalent strengths are needed to switch the output. When the magnetic fields are removed (B → 0) the device remains in the same state until a magnetic field of the opposite polarity and of sufficient strength causes it to switch. The hysteresis of latch mode behavior is shown in panel A of figure 1. B– 0 BHYS VCC VOUT Switch to High Switch to High VOUT(SAT) BRP B+ 0 V+ B+ 0 VOUT(SAT) B– BOP BRP VCC VOUT VOUT V+ BOP BHYS BOP 0 (C) Switch to Low VOUT(SAT) B– (D) Switch to Low Switch to High VCC Switch to Low 0 GND (B) V+ Sensor Output VOUT BRP (A) A120x RL 0 B+ BHYS Figure 1. Bipolar Device Output Switching Modes. These behaviors can be exhibited when using a circuit such as that shown in panel D. Panel A displays the hysteresis when a device exhibits latch mode (note that the BHYS band incorporates B= 0), panel B shows unipolar switch behavior (the BHYS band is more positive than B = 0), and panel C shows negative switch behavior (the BHYS band is more negative than B = 0). Bipolar devices, such as the 120x family, can operate in any of the three modes. 8 A1201-DS, Rev. 2 Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com A1201, A1202, A1203, and A1204 Continuous-Time Bipolar Switch Family the field is reduced beyond the BOP level, the device switches back to the low state. Bipolar devices adopt an indeterminate output state when powered-on in the absence of a magnetic field or in a field that lies within the hysteresis band of the device. The typical output behavior of the A120x devices is latching. That is, switching to the low state when the magnetic field at the Hall sensor exceeds the operate point threshold, BOP . At this point, the output voltage is VOUT(SAT). When the magnetic field is reduced to below the release point threshold, BRP , the device output, VOUT , goes high. The values of the magnetic parameters are specified in the Magnetic Characteristics table, on page 3. Note that, as shown in figure 1, these switchpoints can lie in either north or south polarity ranges. For more information on Bipolar switches, refer to Application Note 27705, Understanding Bipolar Hall Effect Sensors. CONTINUOUS-TIME BENEFITS Continuous-time devices, such as the A120x family, offer the fastest available power-on settling time and frequency response. Due to offsets generated during the IC packaging process, continuous-time devices typically require programming after packaging to tighten magnetic parameter distributions. In contrast, chopper-stabilized switches employ an offset cancellation technique on the chip that eliminates these offsets without the need for after-packaging programming. The tradeoff is a longer settling time and reduced frequency response as a result of the chopper-stabilization offset cancellation algorithm. The A120x family is designed to attain a small hysteresis, and thereby provide more sensitive switching. Although this means that true latching behavior cannot be guaranteed in all cases, proper switching can be ensured by use of both south and north magnetic fields, as in a ring magnet. The hysteresis of the A120x family allows clean switching of the output, even in the presence of external mechanical vibration and electrical noise. 1 2 3 4 5 VCC t VOUT t tPO(max) Output Sampled Figure 2. Continuous-Time Application, B < BRP.. This figure illustrates the use of a quick cycle for chopping VCC in order to conserve battery power. Position 1, power is applied to the device. Position 2, the output assumes the correct state at a time prior to the maximum Power-On Time, tPO(max). The case shown is where the correct output state is HIGH . Position 3, tPO(max) has elapsed. The device output is valid. Position 4, after the output is valid, a control unit reads the output. Position 5, power is removed from the device. 9 A1201-DS, Rev. 2 Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com A1201, A1202, A1203, and A1204 Continuous-Time Bipolar Switch Family The choice between continuous-time and chopper-stabilized designs is solely determined by the application. Battery management is an example where continuous-time is often required. In these applications, VCC is chopped with a very small duty cycle in order to conserve power (refer to figure 4). The duty cycle is controlled by the power-on time, tPO, of the device. Because continuous-time devices have the shorter power-on time, they are the clear choice for such applications. For more information on the chopper stabilization technique, refer to Technical Paper STP 97-10, Monolithic Magnetic Hall Sensor Using Dynamic Quadrature Offset Cancellation and Technical Paper STP 99-1, Chopper-Stabilized Amplifiers with a Track-and-Hold Signal Demodulator. ADDITIONAL APPLICATIONS INFORMATION Extensive applications information for Hall-effect sensors is available in: • Hall-Effect IC Applications Guide, Application Note 27701 • Hall-Effect Devices: Gluing, Potting, Encapsulating, Lead Welding and Lead Forming, 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. 10 A1201-DS, Rev. 2 Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com A1201, A1202, A1203, and A1204 Continuous-Time Bipolar Switch Family Power Derating 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, RθJA, 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, RθJC, is relatively small component of RθJA. Ambient air temperature, TA, and air motion are significant external factors, damped by overmolding. The effect of varying power levels (Power Dissipation, PD), can be estimated. The following formulas represent the fundamental relationships used to estimate TJ, at PD. PD = VIN × IIN (1) ∆T = PD × RθJA (2) TJ = TA + ∆T (3) Example: Reliability for VCC at TA = 150°C, package UA, using minimum-K PCB. Observe the worst-case ratings for the device, specifically: RθJA = 165°C/W, TJ(max) = 165°C, VCC(max) = 24 V, and ICC(max) = 7.5 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 ÷ RθJA = 15°C ÷ 165 °C/W = 91 mW Finally, invert equation 1 with respect to voltage: VCC(est) = PD(max) ÷ ICC(max) = 91 mW ÷ 7.5 mA = 12.1 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 RθJA. 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 = 4 mA, and RθJA = 140 °C/W, then: PD = VCC × ICC = 12 V × 4 mA = 48 mW ∆T = PD × RθJA = 48 mW × 140 °C/W = 7°C TJ = TA + ∆T = 25°C + 7°C = 32°C A worst-case estimate, PD(max), represents the maximum allowable power level (VCC(max), ICC(max)), without exceeding TJ(max), at a selected RθJA and TA. 11 A1201-DS, Rev. 2 Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com A1201, A1202, A1203, and A1204 Continuous-Time Bipolar Switch Family Package LH, 3-Pin (SOT-23W) Package UA, 3-Pin 12 A1201-DS, Rev. 2 Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com A1201, A1202, A1203, and A1204 Continuous-Time Bipolar Switch Family The products described herein are manufactured under one or more of the following U.S. patents: 5,045,920; 5,264,783; 5,442,283; 5,389,889; 5,581,179; 5,517,112; 5,619,137; 5,621,319; 5,650,719; 5,686,894; 5,694,038; 5,729,130; 5,917,320; and other patents pending. 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 products are not authorized for use as critical components in life-support devices or systems without express written approval. 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. Copyright © 2005, Allegro MicroSystems, Inc. 13 A1201-DS, Rev. 2 Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com