HMC1051/HMC1052/HMC1053 SENSOR PRODUCTS 1, 2 AND 3-AXIS MAGNETIC SENSORS Features x Miniature Surface-Mount Packages x Wide Field Range of ± 6 Gauss x 1.0 mV/V/gauss Sensitivity x Low Power Operation Down to 1.8V x Patented On-chip Set/Reset and Offset Straps Product Description The Honeywell HMC1051, HMC1052 and HMC1053 are high performance magnetoresistive sensor designs on a single chip (HMC1051, HMC1052) or two chips (HMC1053). The advantages of these patented chips include orthogonal two-axis sensing (HMC1052), ultra small size and low cost in miniature surface mount packages. Each of the magneto-resistive sensors are configured as a 4-element wheatstone bridge to convert magnetic fields to differential output voltages. Capable of sensing fields down to 120 micro-gauss, these sensors offer a compact, high sensitivity and highly reliable solution for low field magnetic sensing. APPLICATIONS HMC1052 Circuit Diagram x Compassing x Navigation Systems x Attitude Reference x Traffic Detection (9 (9) ) (3 (3) ) x Medical Devices x Position Sensing Solid State Electronics Center • www.magneticsensors.com • (800) 323-8295 • Page 1 HMC1051/HMC1052/HMC1053 SENSOR PRODUCTS SPECIFICATIONS Characteristics Conditions* Min Typ Max Units Bridge Elements Supply Vbridge referenced to GND 1.8 3.0 20 Volts Resistance Bridge current = 10mA 800 1000 1500 ohms Operating Ambient -40 125 °C Temperature Storage Ambient, unbiased -55 150 °C Temperature Humidity Tested at 85°C 85 % Field Range Full scale (FS) – total applied field -6 +6 gauss Linearity Error Best fit straight line ± 1 gauss 0.1 ± 3 gauss 0.5 %FS ± 6 gauss 1.8 Hysteresis Error 3 sweeps across ±3 gauss 0.06 %FS Repeatability Error 3 sweeps across ±3 gauss 0.1 %FS Bridge Offset Offset = (OUT+) – (OUT-) -1.25 ±0.5 +1.25 mV/V Field = 0 gauss after Set pulse Sensitivity Set/Reset Current = 0.5A 0.8 1.0 1.2 mV/V/gauss Noise Density @ 1kHz, Vbridge=5V 50 nV/sqrt Hz Resolution 50Hz Bandwidth, Vbridge=5V 120 Pgauss Bandwidth Magnetic signal (lower limit = DC) 5 MHz Disturbing Field Sensitivity starts to degrade. 20 gauss Use S/R pulse to restore sensitivity. Sensitivity T = -40 to 125°C, Vbridge=5V -3000 -2700 -2400 ppm/°C A Tempco T = -40 to 125°C, Ibridge=5mA -600 A Bridge Offset T = -40 to 125°C, No Set/Reset ±500 ppm/°C A Tempco T = -40 to 125°C, With Set/Reset ±10 A Bridge Ohmic Vbridge=5V, T = -40 to 125°C 2100 2500 2900 ppm/°C A Tempco Cross-Axis Effect Cross field = 1 gauss, Happlied = ±1 gauss ±3 %FS Max. Exposed No perming effect on zero reading 10000 gauss Field Sensitivity Ratio of T = -40 to 125°C 95 100 105 % A X,Y Sensors (HMC1052 Only) X,Y sensor Sensitive direction in X and Y sensors 0.01 degree Orthogonality (HMC1052) * Tested at 25°C except stated otherwise. Solid State Electronics Center • www.magneticsensors.com • (800) 323-8295 • Page 2 HMC1051/HMC1052/HMC1053 SENSOR PRODUCTS SPECIFICATIONS Characteristics Conditions* Min Typ Max Units Set/Reset Strap Resistance Measured from S/R+ to S/R- 3 4.5 6 ohms Current 0.1% duty cycle, or less, 0.4 0.5 4 Amp 2Psec current pulse Resistance T = -40 to 125°C 3300 3700 4100 ppm/°C A Tempco Offset Straps Resistance Measured from OFFSET+ to OFFSET- 12 15 18 ohms Offset DC Current 10 mA/gauss Constant Field applied in sensitive direction Resistance T = -40 to 125°C 3500 3900 4300 ppm/°C A Tempco * Tested at 25°C except stated otherwise. PIN CONFIGURATIONS (Arrow indicates direction of applied field that generates a positive output voltage after a SET pulse.) HMC1051 Vcc (3) HMC1051Z Pinout HMC1051 HONEYWELL HMC1051Z BRIDGE A BRIDGE B 12345678 Vo+(A) Vo-(A) GND1(B) GND2(B) GND Plane (2) (8) (1) (5) (4) Set/Reset Strap S/R+ S/R- (6) (7) HMC1051ZL HMC1051ZL Pinout 8 8 8 7 7 7 6 6 6 5 5 5 4 4 4 3 3 3 2 2 2 1 1 1 VB VB VB VO+ VO+ VO+ OFF+ OFF+ OFF+ GN GN GND D D VO- VO- VO- S/R- S/R- S/R- S/R+ S/R+ S/R+ OFF- OFF- OFF- Solid State Electronics Center • www.magneticsensors.com • (800) 323-8295 • Page 3 HMC1051/HMC1052/HMC1053 SENSOR PRODUCTS HMC1052 HMC1052 Pinout Vcc Vcc (5) (5) 10 9 8 7 6 HM HMC10 C105 52 2 B BR BRIID DGE A GE A B BRIDGE B RIDGE B HMC A 1052 OUT OUT- - GN GND D2 2 G GND1 ND1 OU OUT T+ + OU OUT T- - GN GND D OU OUT T+ + (10) (10) (9) (9) (3 (3) ) (4) (4) (7) (7) (1) (1) (2 (2) ) 12345 S Se et/Re t/Res se ett Stra Strap p S/ S/R R+ + S/R- S/R- (6 (6) ) (8) (8) HMC1052L HMC1052L Pinout HMC1053 HMC1053 Pinout Solid State Electronics Center • www.magneticsensors.com • (800) 323-8295 • Page 4 HMC1051/HMC1052/HMC1053 SENSOR PRODUCTS PACKAGE OUTLINES PACKAGE DRAWING HMC1051Z (8-PIN SIP) Symbol Millimeters Inches x 10E-3 Min Max Min Max A 1.371 1.728 54 68 A1 0.101 0.249 4 10 B 0.355 0.483 14 19 D 9.829 11.253 387 443 E 3.810 3.988 150 157 e 1.270 ref 50 ref H 6.850 7.300 270 287 h 0.381 0.762 15 30 PACKAGE DRAWING HMC1051ZL (8-PIN IN-LINE LCC) PACKAGE DRAWING HMC1052 (10-PIN MSOP) Symbol Millimeters Inches x 10E-3 Min Max Min Max A - 1.10- 43 A1 0.05 0.15 2.0 5.9 B 0.15 0.30 5.9 11.8 D 2.90 3.10 114 122 E1 2.90 3.10 114 122 e 0.50 BSC 2.0 BSC E 4.75 5.05 187 199 L1 0.95 BSC 37.4 Solid State Electronics Center • www.magneticsensors.com • (800) 323-8295 • Page 5 HMC1051/HMC1052/HMC1053 SENSOR PRODUCTS PACKAGE DRAWING HMC1052L (16-PIN LCC) Symbol Millimeters min max A 0.80 1.00 A1 0 0.05 A3 0.20 REF b 0.18 0.30 D3.00BSC D2 1.55 1.80 E3.00BSC E2 1.55 1.80 e0.50BSC L 0.30 0.50 N16 ND 4 NE 4 r B(min)/2 aaa 0.15 bbb 0.10 ccc 0.10 PACKAGE DRAWING HMC1053 (16-PIN LCC) Solid State Electronics Center • www.magneticsensors.com • (800) 323-8295 • Page 6 HMC1051/HMC1052/HMC1053 SENSOR PRODUCTS Basic Device Operation The Honeywell HMC105X family of magnetoresistive Cross-Axis Effect sensors are Wheatstone bridge devices to measure magnetic fields. With power supply applied to a bridge, Cross-Axis effect for the HMR105X series is typically the sensor converts any incident magnetic field in the specified at ±3% of full scale to 1 gauss. See sensitive axis direction to a differential voltage output. application note AN215 regarding this effect and In addition to the bridge circuit, the sensor has two on- methods for nulling. chip magnetically coupled straps; the offset strap and the set/reset strap. These straps are Honeywell Offset Strap patented features for incident field adjustment and magnetic domain alignment; and eliminate the need The offset strap is a spiral of metalization that couples for external coils positioned around the sensors. in the sensor element’s sensitive axis. In two-axis designs, the strap is common to both bridges and must The magnetoresistive sensors are made of a nickel- be multiplexed if each bridge requires a different strap iron (Permalloy) thin-film deposited on a silicon wafer current. In three-axis designs, the A and B bridges are and patterned as a resistive strip element. In the together with the C bridge sharing a common node for presence of a magnetic field, a change in the bridge series driving all three bridges’ offset straps. Each resistive elements causes a corresponding change in offset strap measures nominally 15 ohms, and voltage across the bridge outputs. requires 10mA for each gauss of induced field. The straps will easily handle currents to buck or boost These resistive elements are aligned together to have fields through the ±6 gauss linear measurement range, a common sensitive axis (indicated by arrows on the but designers should note the extreme thermal heating pinouts) that will provide positive voltage change with on the die when doing so. magnetic fields increasing in the sensitive direction. Because the output only is in proportion to the one- With most applications, the offset strap is not utilized dimensional axis (the principle of anisotropy) and its and can be ignored. Designers can leave one or both magnitude, additional sensor bridges placed at strap connections (Off- and Off+) open circuited, or orthogonal directions permit accurate measurement of ground one connection node. Do not tie both strap arbitrary field direction. The combination of sensor connections together to avoid shorted turn magnetic bridges in two and three orthogonal axis permit circuits. applications such as compassing and magnetometry. Set/Reset Strap The offset strap allows for several modes of operation when a direct current is driven through it. These The set/reset strap is another spiral of metalization modes are: 1) Subtraction (bucking) of an unwanted that couples to the sensor elements easy axis external magnetic field, 2) null-ing of the bridge offset (perpendicular to the sensitive axis on the sensor die). voltage, 3) Closed loop field cancellation, and 4) Auto- Like the offset strap, the set/reset strap runs through a calibration of bridge gain. pair of bridge elements to keep the overall die size compact. Each set/reset strap has a nominal The set/reset strap can be pulsed with high currents resistance of 3 to 6 ohms with a minimum required for the following benefits: 1) Enable the sensor to peak current of 400mA for reset or set pulses. With perform high sensitivity measurements, 2) Flip the rare exception, the set/reset strap must be used to polarity of the bridge output voltage, and 3) periodically condition the magnetic domains of the Periodically used to improve linearity, lower cross-axis magneto-resistive elements for best and reliable effects, and temperature effects. performance. Noise Characteristics A set pulse is defined as a positive pulse current entering the S/R+ strap connection. The successful The noise density for the HMR105X series is around result would be the magnetic domains aligned in a 50nV/sqrt Hz at the 1 Hz corner, and quickly drops forward easy-axis direction so that the sensor bridge’s below 10nV/sqrt Hz at 5Hz and begins to fit the polarity is a positive slope with positive fields on the Johnson Noise value at just below 5nV/sqrt Hz beyond sensitive axis result in positive voltages across the 50Hz. The 10Hz noise voltage averages around 1.4 bridge output connections. micro-volts with a 0.8 micro-volts standard deviation. A reset pulse is defined as a negative pulse current entering the S/R+ strap connection. The successful Solid State Electronics Center • www.magneticsensors.com • (800) 323-8295 • Page 7 HMC1051/HMC1052/HMC1053 SENSOR PRODUCTS result would be the magnetic domains aligned in a accuracy, a single polarity pulse circuit may be reverse easy-axis direction so that sensor bridge’s employed (all sets or all resets). With these uni-polar polarity is a negative slope with positive fields on the pulses, several pulses together become close in sensitive axis result in negative voltages across the performance to a set/reset pulse circuit. Figure 1 bridge output connections. shows a quick and dirty manual pulse circuit for uni- polar application of pulses to the set/reset strap. Typically a reset pulse is sent first, followed by a set pulse a few milliseconds later. By shoving the magnetic domains in completely opposite directions, any prior magnetic disturbances are likely to be Is Iset et completely erased by the duet of pulses. For simpler circuits with less critical requirements for noise and 5 v 5 vo ollt ts s Figure 1 Application Notes Set Pulse Circuit Low Cost 2-Axis Compass Very high precision measurements can be made using the HMC105X family of sensors when interfaced with low noise amplifiers and 12 to 16-bit Analog-to-Digital (A/D) converters. For lower resolution (3° accuracy or more) or low cost compass applications, 8 or 10-bit A/D converters may be used with general purpose operational amplifiers. Figure 2 shows a typical 2-axis compassing application using readily available off-the-shelf components. The basic principle of two-axis compassing is to orient the two sensor bridge elements horizontal to the ground (perpendicular to the gravitational field) and to measure the resulting X and Y analog output voltages. With the amplified sensor bridge voltages near-simultaneously converted (measured) to their digital equivalents, the arc- tangent Y/X can be computed to derive the heading information relative to the X-axis sensitive direction. See the application notes on compassing at Honeywell Magnetic Sensors website (www.magneticsensors.com) for basic principles and detailed application information. U1 U1 Vcc Vcc 1nf 1nf 500k 500k 2.5 to 3.6v 2.5 to 3.6v 5.00k 5.00k LM LMV358 V358 5.00k 5.00k U3 U3 500k 500k enabl enable e Vr Vref ef/2 /2 1 1 U2 U2 M MA AX X1 1118 118 data_out data_out H HM MC C1052 1052 0 0 clk_ clk_in in 1nf 1nf 500k 500k Vre Vreff 5.00k 5.00k LM LMV358 V358 5.00k 5.00k 500k 500k Vr Vref ef/2 /2 Figure 2 .1uf .1uf U4 U4 set/r set/reset eset set/r set/reset eset Two-Axis Compass ( (2 2) ) IR IRF F7509 7509 U5 U5 off offs set et _s _set/r et/res eset et Solid State Electronics Center • www.magneticsensors.com • (800) 323-8295 • Page 8 HMC1051/HMC1052/HMC1053 SENSOR PRODUCTS Set/Reset Circuit Notes The above set/reset circuit in Figure 1using the Vs Vsr r 20 200 0:: IRF7507 dual complementary MOSFETs is shown in Vcc Vcc 1 1PPff + + detail by Figure 2 in its H-bridge driven configuration. IRF7 IRF750 509(P) 9(P) S S - - This configuration is used primarily in battery operated applications were the 500mA nominal set/reset pulsed currents can be best obtained under low voltage G G .1 .1PPff D D conditions. se set/r t/re ese sett D D G G Vs Vsr r The 200-ohm resistor trickle charges the 1uf supply R Rs set et/ /r res eset et reservoir capacitor to the Vcc level, and isolates the IIR RF75 F7509(P 09(P) ) S S S S battery from the high current action of the capacitors 4 4:: IIR RF75 F7509(N) 09(N) and MOSFET switches. Under conventional logic states G G one totem pole switch holds one node of the 0.1uf D D _s _set/ et/r res eset et capacitor low, while the other switch charges Vcc into D D the capacitors opposite node. At the first logic change, G G the capacitor exhibits almost a twice Vcc flip of polarity, Figure 3 giving the series set/reset strap load plenty of pulse S S H-Bridge Driver IIR RF75 F7509(N) 09(N) current. A restoring logic state flip uses the 0.1uf capacitors stored energy to create a second nearly equal but opposite polarity current pulse through the set/reset strap. Vs Vsr r 200 200:: Vc Vcc c For operation at normal 3.3 or 5-volt logic levels, a 1 1PPff + + single complementary MOSFET pair can be used in a IRF IRF7 7509( 509(P) P) S S - - single ended circuit shown in Figure 4. Other complementary MOSFET pairs can be used with the G G .1 .1PPff caution that the chosen devices should have less than D D set/reset set/reset 0.5 ohms ON resistance and be able to handle the D D needed supply voltages and set/reset currents. Note G G Rset/r Rset/reset eset that even a 1Hz rate of set/reset function draws an average current of less than 2 microamperes. S S 4 4:: IRF IRF7509( 7509(N) N) Figure 4 Single-Ended Driver Magnetic Field Detection For simple magnetic field sensing applications such Magnetic Anomaly Detectors (MADs) and Magnetometers, a similar circuit to the compass application can be implemented using one, two, or three magnetic sensors. In the example circuit in Figure 5, a HMC1051Z sensor bridge is used with a low voltage capable dual op-amp to detect sufficient intensity of a magnetic field in a single direction. Uses of the circuit include ferrous object detection such as vehicle detection, a “sniffer” for currents in nearby conductors, and magnetic proximity switching. By using two or three sensor circuits with HMC1051, HMC1052, or HMC1053 parts, a more omni-directional sensing pattern can be implemented. There is nothing special in choosing the resistors for the differential op-amp gain stages other than having like values (e.g. the two 5k: and the 500k: resistors) matched at 1% tolerance or better to reject common- mode interference signals (EMI, RFI). The ratio of the 500k:/5k: resistors sets the stage gain and can be optimized for a specific purpose. Typical gain ratios for compass and magnetometer circuits using the HMC105X family, range from 50 to 500. The choice of the 5k: value sets impedance loading seen by the sensor bridge network and should be about 4 kilo-ohms or higher for best voltage transfer or matching. Note that Figure 5 also shows an alternative set/reset strap driver circuit using two darlington complentary paired BJTs as electronic switches. Solid State Electronics Center • www.magneticsensors.com • (800) 323-8295 • Page 9 HMC1051/HMC1052/HMC1053 SENSOR PRODUCTS U1 U1 Vcc Vcc Vcc Vcc .1 .1PPff 5 500k 00k 5.0v 5.0v 10 10k k:: po pot t 5. 5.00k 00k T Th hr re esho sholld Se d Set t - - T TL LC072 C072 + + 5. 5.00k 00k U2 U2 ou outp tput ut 500 500k k - - TL TLC0 C07 72 2 V Vcc/2 cc/2 + + LE LED D H HM MC C105 1051 1 10 10k k:: Vc Vcc c R RLED LED * * Lo Low w E ES SR R T Tant anta allu um m 20 200 0:: 1 1PPf* f* - - + + 10 10k k:: 0. 0.1 1PPff FMM FMMT T71 717 7 .1 .1uf uf se set/re t/res set et set set/ /rese reset t FMM FMMT T61 617 7 SR S R 0. 0.1 1PPff of off fs set et Figure 5 10 10k k:: Magnetic Field Detector Alternating or Direct Current Sensing The HMC105X family sensors can be utilized in a novel way for moderate to high current sensing applications using a nearby external conductor providing the sensed magnetic field to the bridge. Figure 6 shows a HMC1051Z used as a current sensor with thermistor element performing a temperature compensation function for greater accuracy over a wide range of operational temperatures. Selection of the temperature compensation (tempco) resistors used depends on the thermistor chosen and is dependant on the thermistor’s %/°C shift of resistance. For best op-amp compatibility, the thermistor resistance should be above about 1000 ohms. The use of a 9-volt alkaline battery supply is not critical to this application, but permits fairly common operational amplifiers such as the 4558 types to be used. Note that the circuit must be calibrated based on the final displacement of the sensed conductor to the measuring bridge. Typically, an optimally oriented measurement conductor can be placed about one centimeter away from the bridge and have reasonable capability of measuring from tens of milliamperes to beyond 20 amperes of alternating or direct currents. See application note AN-209 for the basic principles of current sensing using AMR bridges. te tem mp pco co R R R R a a b b s sttan andof dofff di dis sttanc ance e ne nettw wo or rk k U1 U1 Vc Vcc c = = 9V 9Vdc dc R R th th .1 .1PPff 500 500k k - - RC4458 RC4458 5. 5.00k 00k - - R RC C45 4558 58 + + out output put + + 5. 5.00k 00k U2 U2 5 500k 00k Figure 6 V Vc cc c/ /2 2 ~ +4 ~ +4. .5 5V Vd dc c HM HMC1 C10 05 51 1 Current Sensor V Vcc = cc =9 9Vd Vdc c * * Lo Low w E ES SR R T Tan anta talu lum m 200 200:: 1 1PPf* f* - - + + II ac ac II dc dc . .1uf 1uf s se ett//rese resett set set//rese resett Si Si1 1553 553D DL L of offfs se ett U3 U3 Con Condu ductor t ctor to o be be Cur Curr re en ntt Meas Measu ur red ed Solid State Electronics Center • www.magneticsensors.com • (800) 323-8295 • Page 10 HMC1051/HMC1052/HMC1053 SENSOR PRODUCTS Three Axis Compassing with Tilt Compensation For full three-axis compassing, the circuit depicted in Figure 7 shows both a HMC1051 and a HMC1052 used for sensing the magnetic field in three axes. Alternatively a single HMC1053 could be used for a single sensor package design. A two-axis accelerometer with digital (PWM) outputs is also shown to provide pitch and roll (tilt) sensing, to correct the three-axis magnetic sensors outputs into to the tilt-compensated two-axis heading. The accelerometer can be substituted with a fluidic 2-axis tilt sensor if desired. For lower voltage operation with Lithium battery supplies (2.5 to 3.6Vdc), the Set/Reset circuit should be upgraded from a single IRF7507 to the dual IRF7507 implementation (per Figure 2) to permit a minimum 1-ampere pulse (500mA per set/reset strap resistance) to both the HMC1052 and HMC1051 sensors. U1 U1 Vc Vcc c 1n 1nf f 50 500k 0k 3. 3.3 to 5.0v 3 to 5.0v Vc Vcc c 5.0 5.00 0k k AN AN0 0 LM LMV324 V324 AN AN1 1 5.0 5.00 0k k AN AN2 2 U3 U3 50 500k 0k V Vcc/ cc/2 2 V Vcc/ cc/2 2 AN AN3 3 HM HMC10 C105 52 2 se set/rese t/reset t DO DO0 0 1n 1nf f 50 500k 0k 5.0 5.00 0k k U6 U6 LM LMV324 V324 5.0 5.00 0k k 50 500k 0k PPC C V Vcc/ cc/2 2 with with .1u .1uf f U4 U4 se set/res t/rese et t Multiplex Multiplexe ed d A/D Conv A/D Conv. . IR IRF75 F750 09 9 Vc Vcc c of off fs se et t U5 U5 se set/res t/rese et t T Tw wo-ax o-axiis s accel accele er ro om me eter ter Vc Vcc c .1 .1PPff 50 500k 0k U2 U2 5.0 5.00 0k k - - LM LMV324 V324 xo xou utt DI0 DI0 + + 5.0 5.00 0k k yo yout ut DI1 DI1 50 500k 0k V Vcc/ cc/2 2 HM HMC10 C105 51 1 Figure 7 Three Axis Compass Solid State Electronics Center • www.magneticsensors.com • (800) 323-8295 • Page 11 HMC1051/HMC1052/HMC1053 SENSOR PRODUCTS Duty Cycling for Lower Energy Consumption For battery powered and other applications needing limited energy consumption, the sensor bridge and support electronics can be switched “off” between magnetic field measurements. The HMC105X family of magnetic sensors are very low capacitance (Bandwidth > 5MHz) sensor bridges and can stabilize quickly, typically before the support electronics can. Other energy saving ideas would be to minimize the quantity of set/reset pulses which saves energy over the battery life. Figure 8 shows a simple supply switching circuit that can be microprocessor controlled to duty cycle (toggle) the electronics in moderate current (<25mA) applications. Vc Vcc c M MM MBT BT2 2907AL 907ALT T1 1 T To o Sensor Sensor C Ciir rc cui uits ts Vcc Vcc 0.01 0.01PPff + + Gnd Gnd 10 10PPff - - PPC C * * U Us sed w ed wh hen Vc en Vcc c = = 5 5. .0 v 0 vo ollt ts, s, jumper jumper * *M MM MB BD D7 7001 001LT LT1 1 w when us hen usiin ng g Vcc Vcc = = 3. 3.3 3 v vol olts ts or or l le es ss s. . Of Off f Figure 8 On On toggl toggle e Duty Cycling 10k 10k:: ORDERING INFORMATION Part Number Package Style HMC1051Z One Axis Magnetic Sensor – SIP8 HMC1051ZL One Axis Magnetic Sensor – 8-PIN IN-LINE LCC HMC1052 Two Axis Magnetic Sensors – MSOP10 HMC1052L Two Axis Magnetic Sensors – 16-PIN LCC HMC1053 Three Axis Magnetic Sensors – 16-PIN LCC The application circuits herein constitute typical usage and interface of Honeywell product. Honeywell does not warrant or assume liability for customer-designed circuits derived from this description or depiction. Honeywell reserves the right to make changes to improve reliability, function or design. Honeywell does not assume any liability arising out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the rights of others. This product may be covered by one or more of the following U.S. Patents: 4569742 4681812 4847584 4857418 4945397 5019461 5247278 5820924 5952825 and 6529114. 900308 10-03 Rev. - Solid State Electronics Center • www.magneticsensors.com • (800) 323-8295 • Page 12