AG920-07E NVE, AG920-07E Datasheet
AG920-07E
Specifications of AG920-07E
Related parts for AG920-07E
AG920-07E Summary of contents
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... Low Field Detection in Currency Applications • Current Sensing in PCB Traces and Wires • Overcurrent and Short Circuit Detection • Vehicle Detection for Traffic Counting Applications Table of Contents Introduction to NVE GMR Sensors .................................................................................................. 4 GMR Materials Overview............................................................................................................. 5 Basic Sensor Design ..................................................................................................................... 7 Signal Processing........................................................................................................................ 11 AA and AB-Series Analog Sensors ................................................................................................ 12 AA Sensors ...
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... DD-Series Signal Processing ICs................................................................................................ 70 Evaluation Kits ............................................................................................................................... 73 AG001-01 Analog Sensor Evaluation Kit .................................................................................. 74 AG003-01 Current Sensor Evaluation Kit .................................................................................. 75 AG910-07 and AG911-07 GMR Switch Evaluation Kits........................................................... 76 AG920-07 GT Sensor Evaluation Kit......................................................................................... 77 Application Notes for GMR Sensors .............................................................................................. 78 General Comments ..................................................................................................................... 79 Competitive Technologies .......................................................................................................... 79 GMR Material Physics ............................................................................................................... 80 GMR Materials Types Manufactured by NVE ........................................................................... 84 Temperature Characteristics of GMR Sensors ...
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... GMR technology, a line of magnetic field sensors that outperform traditional Hall Effect and AMR magnetic sensors. NVE introduced its first analog sensor product in 1995. Since then, our product line has grown to include several variations on analog sensors, the GMR Switch line of precision digital sensors, and our newest products, the GT Sensors ...
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... Various alloys of these materials are deposited in layers as thin as 15 Angstroms (five atomic layers!), and as thick as 18 microns, in order to manufacture the GMR sensor elements used in NVE’s products. ...
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... Applie d Ma gnetic Fie ld (Gauss) The material shown in the plot is used in most of NVE’s GMR sensor products. It provides a 98% linear output from 10% to 70% of full scale, a large GMR effect (13% to 16%), a stable temperature coefficient (0.14%/°C) and temperature tolerance (+150°C), and a large magnetic field range (0 to ± ...
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... These three basic sensor element types are described in the sections below. Magnetometers NVE’s magnetometers are covered by our basic GMR material and sensor structure patents and have unique features designed to take advantage of the characteristics of GMR sensor materials. A photomicrograph of an NVE sensor element is shown below: ...
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... The second purpose of the flux concentrators is to vary the sensitivity of the sensor element from product to product. They work by forming a low reluctance path to the sensor elements placed between them. NVE uses a “rule of thumb” formula to calculate the effect of the flux concentrators: Field at sensor elements ≅ (Applied Field)(60%)(FC length / gap between FCs) For the sensor shown in the previous photo, the length of each flux concentrator is 400 microns, and the gap between the flux concentrators is 100 microns ...
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... In practice, the gradient fields are typically not high enough to give this maximum signal, but signal levels 200 mV are common. NVE’s GMR differential sensors are typically designed with two of the bridge resistors at one end of the IC, and two at the other end. The spacing between the two sets of resistors, combined with the magnetic field gradient on the IC, will determine the output signal from the sensor element ...
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... Spin Valve Sensors NVE’s spin valve sensors are designed using our synthetic anti-ferromagnet pinned layer. This pinned layer is very robust, and not subject to upset or reset. The basic GMR material construction includes the pinned layer and a free layer; the free layer can be influenced by an external magnetic field in the range 200 Gauss ...
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... For the GMR Switch products, NVE adds a simple comparator and output transistor circuit to create the world’s most precise digital magnetic sensor. For these products, no amplification of the sensor’s output signal is necessary ...
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... Temperature Range The AB-Series sensors are differential sensor devices, or gradiometers, which take advantage of the high output characteristics of NVE’s GMR materials. Two families of AB sensors are offered, the standard AB-Series and the ABH-Series. They have operational characteristics similar to the AA and AAH sensors described in the table above but with the bipolar linear output characteristics of a differential sensor ...
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... AB001-00 20 200 ABH001- Notes 1. Oersted (Oe Gauss in air. 2. Unipolar operation means exposure to magnetic fields of one polarity, for example 0 to +30 Gauss -50 Gauss. Bipolar operation (for example +10 Gauss) will increase nonlinearity and hysteresis www.nve.com AA and AB-Series Analog Sensors Maximum Maximum Non- Hyster- linearity esis Uni ...
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... Magnetic Characteristics: Linear Part Saturation Range 1 Number Field (Oe ) Min AA002-02 15 1.5 AA003-02 20 2.0 AA004- AA004- AA005-02 100 10 AA006- AA006- www.nve.com OUT+ V- (ground) Sensitivity Resistance 1 1 (|Oe |) (mV/V-Oe ) (Ohms) Max Min Max 10.5 3.0 4.2 5K ±20 3.2 5K ±20% 35 0.9 1.3 5K ±20% 35 0.9 1.3 5K ±20 ...
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... See the graphs below. 7. Beta (β) is any angle deviation from the sensitive axis. AA002 Temperature Performance Curre nt Supply 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 -20 -15 - -0.05 Applie d M agnetic Field (Oe) www.nve.com Min Typical Max 4 4 < >1 -50 125 - +0.14 +0.03 -0.1 Cos β ...
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... NVE NVE AAxxx AAXXX-02 -02 Orientation chamfer Pin 1 OUT - Axis of Sensitivity Magnetic Characteristics: Part Saturation 1 Number Field (Oe ) Min AAH002-02 6 0.6 AAH004-00 15 1.5 www.nve.com OUT+ V- (ground) Linear Range Sensitivity Resistance 1 1 (|Oe |) (mV/V-Oe ) (Ohms) Max Min Max 3.0 11.0 18.0 2K ±20% 7.5 3.2 4.8 2K ± ...
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... Beta (β) is any angle deviation from the sensitive axis. AAH002 Temperature Performance, 2.28mA Current Source 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 -20 -15 - -0.05 Applied Magnetic Field (Oe) www.nve.com Min Typical Max 4 <1 ±12 DC >1 -50 150 - +0.11 +0.10 0.0 Cos β ...
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... V+ (supply) NVE NVE AAxxx AAXXX-02 -02 Orientation chamfer Pin 1 OUT - Axis of Sensitivity Magnetic Characteristics: Part Saturation 1 Number Field (Oe ) Min AAL002-02 15 1.5 www.nve.com OUT+ V- (ground) Linear Range Sensitivity Resistance 1 1 (|Oe |) (mV/V-Oe ) (Ohms) Max Min Max 10.5 3.0 4.2 5.5K ±20 phone: 952-829-9217 fax: 952-829-9189 ...
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... Beta (β) is any deviation angle from the sensitive axis. AAL002 Temperature Performance, 1mA Current Supply 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 -30 -20 -10 0 -0.05 Applied Magnetic Field (Oe) www.nve.com Min Typical Max 4 4 <1 ±25 DC >1 -50 150 - +0.11 -0.28 -0.40 Cos β ...
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... For either part, the output can be configured to represent the sine and cosine function of the magnetic field being applied to the sensor. Each resistor is 1.5 kΩ nominal resistance and output of each half-bridge is ratiometric with the power supply voltage. The part features NVE’s PLLP6 housing, which 0.9 mm thick surface mount package. ...
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... Four individual sensor resistors are supplied in the package, each with the pinned layer rotated 90º with respect to that of the previous sensor. These resistors can be connected in two half-bridge configurations to provide a sine and cosine output or monitored individually to provide an absolute indication of the angle between the pinned layer and the movable layer. www.nve.com Sensor Element 90 180 ...
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... A drawing showing the ICs position in the package is given below. On each IC there is an arrow indicating the direction of the pinned layer. Functional Block Diagram, Marking, and Pinout, AAV001-11: R3 VCC R1 www.nve.com BBP R2 R3 (Cosine) R2 (Sine) GND R1 (Sine) R4 (Cosine phone: 952-829-9217 fax: 952-829-9189 AAV Sensors ...
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... TCOI Notes : 1. Large Magnetic Fields WILL NOT cause damage to NVE GMR Sensors (Oersted Gauss in air = 0.1 mTesla = 79.8 Amps/meter. 3. TCOV is the percent change in output signal over temperature with a constant voltage source powering the part and TCOI is the percent change in output over temperature with a constant current source. ...
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... X ABxxx-02 Pin 1 OUT A V- (ground) Axis of Sensitivity Magnetic Characteristics: Linear Part Saturation Range 1 Number Field (Oe ) Min AB001-02 250 10 AB001-00 250 10 www.nve.com Functional Block diagram OUT B Y Resistor Sensitivity Resistance 1 1 (| (Ohms) Max Min Max 175 0.02 0.03 2.5K ±20% 175 0.02 0.03 2.5K ± ...
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... V pin-to-pin HBM Maximum voltage range is limited by the power The Figure at left is a simulated output from an NVE Gradiometer. The output / gradient correlation shown assumes one pair of resistors is held at zero 400 field. Note the bipolar output. ...
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... Pinout V+ (supply) NVE X ABxxx-02 Pin 1 OUT A V- (ground) Axis of Sensitivity Magnetic Characteristics: Part Saturation 1 Number Field (Oe ) Min ABH001- www.nve.com Functional Block diagram OUT B Y Linear Resistor Range Sensitivity Resistance 1 1 (| (Ohms) Max Min Max 40 0.06 0.12 1.2K ± ...
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... V pin-to-pin HBM Maximum voltage range is limited by the power The Figure at left is a simulated output from an NVE Gradiometer. The output / gradient correlation shown assumes one pair of resistors is held at zero 400 field. Note the bipolar output. ...
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... The GMR Switch will accurately and reliably sense magnetic fields with less error than any other magnetic sensor on the market today. In addition, there is little shift in the magnetic field operate point of the GMR Switch over voltage and temperature extremes. This gives NVE’s customer the ability to make a high precision, high tolerance magnetic sensing assembly. ...
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... See Appendix for package dimensions Note on Availability of Products NVE keeps about 25 of the most popular types of GMR Switch products in stock at our manufacturing facility. However, because there are over 100 different varieties of GMR Switch parts, some part numbers may require a six to eight week lead time before production quantities are available. Please contact NVE for further information ...
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... All outputs turn ON when the magnetic field is applied. An output that turns OFF when the magnetic field is applied is available as a custom product; please consult NVE. Some of NVE’s GMR Switches also feature a regulated supply voltage available external to the part on a separate pin. This regulator provides a 5.8V reference capable of supplying drive current ...
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... Output Voltage + Short Circuit Detection and Shut-Off Trigger Field, Direction of Sensitivity, Low Voltage Operation The second and third numeric digits of the part number NVE ADxxx-xx specify the magnetic trigger field and direction of sensitivity of the part. Five different magnetic trigger fields are available for the GMR Switch: 10 Gauss (10 Oe, 1 ...
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... Gauss OP, Cross Axis Direction of Sensitivity, Low Volt Note: For parts that operate at 10 Gauss, see the following section describing the NVE ADH-Series sensors. NVE AD-Series Sensitivity Direction and Pin Configuration Pin configuration for the NVE AD-Series GMR Switches is given in the following diagrams. In addition, most GMR Switch parts are available with a choice of two directions of sensitivity. “ ...
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... In addition to these three package types, NVE offers a custom version of the MSOP8 package for the NVE AD024-00 part. In this version, the BD012-00, all three connections are made on one side of the package, and the pins on the other side of the package are clipped off flush with the body of the package ...
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... Typical Operate Points (OP) and Release Points (RP mbient Temperature = 25C Supply Voltage Operate Point (OP) and Release Point (RP) Variation -40 0 Temperature (C) www.nve.com GMR Switch Precision Digital Sensors AD004 and AD005 Over Temperature 40 80 120 - 34 - phone: 952-829-9217 fax: 952-829-9189 AD005 OP AD005 RP AD004 OP AD004 RP AD005 OP AD005 RP AD004 OP AD004 RP ...
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... Operating Temperature Derating Curves for SOIC8, MSOP8, and TDFN6 Packages in Free Air 130 120 110 100 Supply Voltage (V) Output Current Derating Curve 4.5 6 www.nve.com GMR Switch Precision Digital Sensors 7.5 Supply Voltage ( phone: 952-829-9217 fax: 952-829-9189 SOIC8 MSOP8 and TDFN6 9 10.5 ...
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... Speed Sensing Description: The NVE AD0xx-xx to AD7xx-xx GMR Switches are digital output magnetometers that offers precision operate points over all temperature and input voltage conditions. They are available with magnetic trigger fields from Gauss and four different output configurations, making them an extremely flexible and user-friendly design ...
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... Functional Block Diagram (NVE AD08x-xx): 3.0V to 6.0V Output Characteristic as a Function of Magnetic ON -40 Magnetic Characteristics: Typical Operate Minimum Point Operate Point Note: All Values in Oersteds (Oe Gauss in Air www.nve.com GMR Switch Precision Digital Sensors GMR Comparator Bridge Field, for AD024-00 GMR Switch ...
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... Electrical Specifications (NVE AD0xx-xx to NVE AD7xx-xx, except NVE AD08x-xx): Parameter 4 Supply Voltage Supply Current, Single Output 3 Current Sinking Output 3 Current Sourcing Output Output Leakage Current Sinking Output Saturation Voltage Sourcing Output Saturation Voltage 6 Regulated Output Voltage Regulated Output Current Electrical Specifications (NVE AD08x-xx): ...
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... Thermal power dissipation for the packages used by NVE is 240°C/Watt for the SOIC8 package, and 320°C/Watt for the MSOP8 and TDFN6 packages. See the Figure on Ambient Temperature vs. Supply Voltage for derating information. Heat sinking the parts by attaching them to a PCB improves temperature performance. ...
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... Speed Sensing Description: NVE AD8xx and AD9xx GMR Switches are designed specifically for use with an external high current output transistor in industrial control environments. These parts provide the same precise magnetic performance NVE’s GMR Switch is known for with the additional functionality of short circuit protection (SCP) for the output stage of the circuit ...
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... Cap2 Cap AD821-00 Sink2 Ground R LED t Cap t Cap 2 1 Pin 1 Cap2 Cap AD921-00 Source Ground t Cap t Cap 2 1 www.nve.com GMR Switch Precision Digital Sensors VDD R BIAS1 VDD R SHORT ShortH Sink1 R BIAS2 Vreg VDD VDD ShortL Sink1 Vreg R LED R BIAS2 R R BIAS1 ...
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... LED current is required by the user (maximum of 3 mA.) LED Magnetic Characteristics: Typical Operate Minimum Point Operate Point Note: All Values in Oersteds (Oe Gauss in Air www.nve.com GMR Switch Precision Digital Sensors 1 Time Maximum Operate Point Differential 100 - 42 - phone: 952-829-9217 fax: 952-829-9189 on the graph above. Typical value is 16V, 0.01µF, 1 and R are 16kΩ ...
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... Thermal power dissipation for the packages used by NVE is 240°C/Watt for the SOIC8 package, and 320°C/Watt for the MSOP8 and TDFN6 packages. See the Figure on Ambient Temperature vs. Supply Voltage for derating information. Heat sinking the parts by attaching them to a PCB improves temperature performance. ...
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... It offers the same precision operate points over all temperature and input voltage conditions as our other GMR Switch products available in standard form as the NVE ADH025-00 with a magnetic trigger field of 10 Gauss, a current sinking output, and a cross axis configuration. Custom versions with trigger fields ranging from Gauss, and different output options and sensitivity directions could be manufactured for specific customer requirements ...
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... Thermal power dissipation for the packages used by NVE is 240°C/Watt for the SOIC8 package, and 320°C/Watt for the MSOP8 and TDFN6 packages. See the Figure on Ambient Temperature vs. Supply Voltage for derating information. Heat sinking the parts by attaching them to a PCB improves temperature performance. ...
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... GT Sensors Precision Gear Tooth and Encoder Sensors NVE’s GT Sensor products are based on a Low Hysteresis GMR sensor material and are designed for use in industrial speed applications where magnetic detection of gear teeth and magnetic encoder wheels is required. GT Sensors with both analog and digital outputs are available. The analog parts feature the large signal and robust characteristics which NVE’ ...
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... The ABL-Series GT Sensors are differential sensor elements that provide an analog sinusoidal output signal when used with a bias magnet and gear tooth or a magnetic encoder. These chips use NVE’s proprietary GMR sensor elements featuring an extremely large output signal from the raw sensor element, which is stable over the rated temperature and voltage range ...
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... Linearity and Hysteresis measured across linear operating range, unipolar operation. 3. Application of a magnetic field in excess of this value will saturate the GMR sensor elements and no further output will be obtained. No damage occurs to the sensor elements when saturated. NVE GMR sensors will not be damaged by any large magnetic field. 4. ...
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... ABL015 0.500 0.125 - All dimensions All resistors are 5kΩ - Sensor elements are located symmetrically about the center of the IC. Note: ABL006 ABL016 Sensor Element Size and Spacing Not Shown www.nve.com Center of Die and Package 0.140 1.000 0.500 0.500 0.250 1.000 ...
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... ABL006-00 Single ABL014-00 Dual ABL015-00 Dual ABL016-00 Dual ABL004-10 Single ABL005-10 Single ABL006-10 Single ABL014-10 Dual ABL015-10 Dual ABL016-10 Dual www.nve.com VCC R4 R1 OUT GND ABL014, ABL015, ABL016 Schematic (Dual Bridge) OUT+1 OUT-2 Phase Shift Element Between Spacing Bridges (Microns) (Microns) ...
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... Pin Configuration: MSOP8 Package Out+ No Connect ABL004-00, ABL005-00, No Connect ABL006-00 Ground TDFN6 Package Out+ ABL004-10, No Connect ABL005-10, ABL006-10 ABL006-10 Gnd www.nve.com VCC Ground1 No Connect Out-1 ABL014-00, ABL015-00, No Connect Out+1 ABL016-00 Out- VCC1 Ground1, VCC Ground2 ABL014-10, No Connect Out-1 ...
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... Linear and Angular Position Sensing Description: NVE offers these products specifically for use as sensors for gear tooth wheels or magnetic encoders with a digital output signal. The pulse output from the sensor corresponds with the gear teeth passing in front of it. When a gear tooth or magnetic pole is in front of the sensor, the sensor’s output goes high ...
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... Supply currents can be factory programmed to different levels, for example 3 mA and 6 mA and 14 mA; contact NVE for details. 3. Pin-to-pin voltage, Human Body Model for ESD 4. Airgap measured with standard ferrous gear tooth; contact NVE for details. www.nve.com Min Typ 4.5 3.2 4 ...
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... Voltage Regulator GMR A Bridge EEPROM Gain Packages: The AKL-Series parts are available in the TDFN8 SO8 package. Please see the package drawing section in the Appendix for dimensions. www.nve.com Element Spacing (Microns) Marking 1000 Part Number 500 Part Number 300 Part Number ...
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... AKL003-12 TEST BRIDGE+ Sensitivity www.nve.com Note: Bridge + and Bridge - are provided for analysis purposes only. NVE does not TEST recommend connecting these pins in a production product for ESD and loading BRIDGE- reasons. Also, all pins labeled “Test” must be floating, i.e., not connected to each other or any other circuit node ...
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... They are designed to be potted or injection molded by the customer to make a complete magnetic sensor assembly with a cable attached and enclosed in a plastic housing. The PCB assemblies include an NVE AD9xx magnetic sensor, a DB001 signal processing IC, plus surrounding signal processing and filtering components. ...
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... Short Circuit Protection Limit Notes: 1. See AD924-00 data in GMR Switch section of this catalog. 2. These parts are assembled with high temperature solder; overmolding at temperatures up to 210°C for 10 seconds is approved. www.nve.com Circuit Board Sensor Products Top View Bottom View Top View Bottom View Min ...
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... AD9xx-xx Source Cap Cross Axis Cap2 t Cap t Cap 1 2 Wiring Diagram: Ground Out VCC www.nve.com Circuit Board Sensor Products Width, inches (mm) 0.755 (19.2) 0.165 (4.2) 0.540 (13.7) 0.115 (2.9) Vreg Vreg Sink In ShortL LED VCC Ground Note: the dotted line pad is on the backside of the PCB ...
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... The bank note is typically magnetized with a permanent magnet before it reaches the sensor array. The residual magnetization in the magnetic ink or stripe of the currency is detected by the sensor array. This information is then analyzed to determine if the currency is genuine. See the figure below: Bank Note Feed Rollers www.nve.com Circuit Board Sensor Products Sensor N Array S ...
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... Since every application is different in terms of circuit board and sensor configuration, NVE does not offer a standard product for this application. However, NVE is prepared to rapidly prototype these assemblies for customer evaluation at a nominal cost. Please contact NVE for details. www.nve.com Circuit Board Sensor Products ...
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... In addition to GMR Sensor products, NVE has begun designing and manufacturing accessory products for our sensors. These products are designed to be used with NVE’s sensors some cases as stand- alone parts, to provide higher level signal processing capabilities coupled with the robust performance characteristics that NVE products are known for. DB-Series Power Switch ICs – ...
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... Usable with Magnetic, Inductive, and Photo Sensors Description: The DB001-00 signal processing IC is designed to take the digital input signal from NVE’s AD9xx GMR Switch and provide a high current switched output corresponding with the sensor input. The part functions as the “front end” complete sensor assembly and includes protection against short circuits and high voltage transients from capacitive and inductive loads ...
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... Ground Packages: Please see the package drawing section in the Appendix for dimensions of the MSOP8 package. Pin Configuration: VCC NVE ISC FFD Source Out Sink Out www.nve.com Peripheral Integrated Circuits 3.3 Volts A mplifie r Thermal Shutdown Vreg In LED Ground - 63 - phone: 952-829-9217 fax: 952-829-9189 ...
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... Reverse Battery Protection Output Current Junction Temperature Range, T Storage Temperature Range Notes : This part has reverse battery protection to -36V 1. 2. Due to package size, MSOP8 package contains 3-letter code to designate part type. www.nve.com Peripheral Integrated Circuits Vreg Vreg Sink In ShortL LED VCC Ground ...
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... LED driver to indicate an “ON” condition. The DB002 is available in the SOIC8 package (p/n DB002-02), as well as in die form (p/n DB002-01 designed to work with NVE’s AD1xx GMR Switch products, or any other current sourcing or CMOS/TTL digital output sensor element such as an inductive sensor or a photo sensor. ...
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... Sink Out Source Out Ground Input Vreg DB002-02 VCC Sink Out Packages: Please see the package drawing section in the Appendix for dimensions of the SOIC8 package. www.nve.com Peripheral Integrated Circuits 5.0 Volts A mplifie r Thermal Shutdown S hort Circuit Detection Circuitry Ground Delay Source ...
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... A capacitor of at least 1nF value must be placed between the Delay pin and ground on the IC. 2. NVE recommends a bypass capacitor between VCC and Ground, 10nF or larger 3. In noisy environments a capacitor may be used on Vreg if necessary 100nF. Electrical characteristics (-40°C to +125°C, unless otherwise noted) ...
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... Input Voltage (DC002-10) Output Voltage (DC002-10) Output Current Bias Current at Zero Output Current Absolute maximum ratings* Parameter Input Voltage Reverse Battery Voltage Output Current Junction Temperature Range, T Storage Temperature Range www.nve.com Peripheral Integrated Circuits Min Typ Max 4.5 36 3.0 3.3 3.6 6 ...
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... Please see the package drawing section in the Appendix for dimensions of the TDFN6 package. Pin Configuration Vreg (Out) DC001-10, No Connect DC002-10 VCC (In) Note: The die attach pad is exposed on the back of this package. NVE recommends that it be connected to the ground pin and the PCB for improved temperature performance. www.nve.com Peripheral Integrated Circuits No Connect Ground No Connect ...
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... Description: The DD-Series signal processing IC is designed to take an analog, sinusoidal input signal such as that provided by NVE’s ABL-Series sensors and convert two wire, current modulated digital output. Inputs as small peak-to-peak can be provided to the IC, along with large signal offsets. The DD001-12 part will provide a 50% duty cycle digital output signal. ...
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... The supply voltage must appear across the power and ground terminals of the part. Any additional voltage drop due to the presence of a series resistor is not included in this specification. 2. Input signal range can be adjusted by programming the amplifier gain to a specific value; contact NVE for details. 3. Supply currents can be factory programmed to different levels, for example 3 mA and 6 mA and 14 mA; contact NVE for details ...
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... The DD-Series parts are available in the TDFN SO8 package. Please see the package drawing section in this catalog for dimensions. Pin Configuration: TDFN-SO8 Package Test Vreg DD001-12 VCC Ground www.nve.com Peripheral Integrated Circuits Offset Detector EEPROM Gain Current Level Note: Bridge + and Bridge Test connected only to the sensor element outputs for ESD and loading reasons ...
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... NVE’s catalog and application notes on CD ROM. In the AG910-07 kit, a socket for easy testing of the MSOP-8L package is also included. AG920- Sensor Evaluation Kit NVE’s newest evaluation kit includes analog and digital versions of the GT sensor product line plus our DD001-12 stand-alone signal processing IC ...
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... AG001-01 Analog Sensor Evaluation Kit The NVE GMR Engineering Evaluation Kit (PN AG001-01) was created as an aid to the technical user of GMR sensors to facilitate laboratory experimentation and development. The kit consists of an assortment of NVE sensors, printed circuit boards and permanent magnets sufficient to demonstrate sensor functionality in the laboratory ...
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... AA003-02 was selected for inclusion in this kit because good medium sensitivity current sensor. In fact, any of NVE’s AA sensor products can be used in this application for more or less sensitivity to the magnetic field generated by the current. The PCB included in the kit has (4) four trace geometries to simulate various PCB current ranges ...
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... These kits were created to facilitate laboratory experimentation and development using NVE’s GMR Switch Digital Output Sensors. The kits consist of sixteen distinct NVE GMR Switches that span the magnetic field range and output types available in the AD-Series sensors. All sensors in this kit are packaged in the MSOP8 miniature surface mount package ...
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... AG920-07 GT Sensor Evaluation Kit This kit was created to facilitate laboratory experimentation and development using NVE’s GT Sensor products. Because of the wide variety of mechanical orientations where these sensors can be used, this kit contains a large variety of circuit boards to simplify the customer’s fixturing and testing of the parts. Included in the kit are one of each type of NVE’ ...
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... NVE Internet Home Page: www.nve.com NVE reserves the right to make product changes and improvements at any time. The information contained herein is believed to be accurate as of the date of printing, however NVE assumes no responsibility for its use. Any errors in the technical data printed in this catalog will be corrected and updated as soon as possible ...
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... Hall effect sensors, and are able to operate at fields well above the range of AMR sensors. In addition, high fields will not “flip” GMR sensors or reverse their output as is possible with AMR sensors. High fields will also not cause damage to NVE GMR sensors the case with some competing GMR sensor products. ...
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... This is done to allow magnetic modulation of the electron spin in the materials. The spin dependence of conduction electrons in magnetic materials, along with the increasing resistivity at very small material thicknesses, combine to make the GMR effect possible. www.nve.com Resistance of the Material Decreases as the Mean Free Path Length of 100 ...
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... The figure below shows a simplified structure of a typical GMR sensor film, as manufactured by NVE: Cross Sectional Structure of Basic GMR Material Top Film (Magnetic Material, 20-50 Angstroms Thick) Conductive Interlayer (Non-Magnetic Material, 15-40 Angstroms Thick) Bottom Film (Magnetic Material, 20-50 Angstroms Thick) The diagram shows two magnetic material layers, sandwiching a non-magnetic interlayer. The magnetic layers are designed to have anti-ferromagnetic coupling ...
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... With and Without an External Magnetic Field Applied; Applying the External Field Results in Lower Device Resistance Resistivity 50 Mean Free Path Length of an Electron (Angstroms) www.nve.com Magnetization Direction of Top Film (Primarily Spin DOWN Electrons, Due to Magnetization Direction) Conductive Interlayer (Primarily Spin DOWN Electrons, ...
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... This change in resistance is the GMR effect. The size of the resistance decrease is typically 4% to over 20%, depending on the material structure of the GMR films. Most of NVE’s sensor products rely on a GMR material which exhibits 14% to 16% decrease in resistance. The “percent GMR” given material is calculated using the following ...
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... GMR Materials Types Manufactured by NVE NVE manufactures four different types of GMR materials for use in our sensor products. These GMR materials are described below: Standard Multilayer (ML) – This GMR material has AF (antiferromagnet) coupling, % GMR in the range of 12% to 16%, magnetic saturation fields of about 300 Oersteds, stable temperature characteristics for operation up to 150° ...
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... The base resistance defined as its maximum resistance at 25°C. This is the resistance with zero applied magnetic field. The base resistance of R2 will vary with temperature (at zero applied field) as described by the following formula Base Resistance * [ 1 + (TCGMR * (Temperature - 25°C))] R2 Zero Field www.nve.com Application Notes R1 R2 Base GMR ...
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... These numbers will provide an accurate indication of the change in the output of the parts over temperature in the linear operating range. Note that this data is provided for NVE’s AA and AB type parts but not for any of the parts that include a signal processing IC in the package. This is because NVE typically builds temperature compensation circuitry into the signal processing IC ...
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... The following graphs show the basic temperature behavior of the three most common types of GMR materials used in NVE’s products. The first graph shows the temperature behavior of an AA002-02 sensor, which is representative of the GMR material used in NVE’s AA, AB, and AD-Series products: 0.35 ...
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... The next graph shows the temperature behavior of an AAL002-02 sensor, which is representative of the GMR material used in NVE’s AAL, ABL, and AKL-Series products: 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 -30 -0.05 www ...
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... For NVE’s AA-Series sensors, this potential error can be as high the sensor is exposed to one polarity of magnetic field (unipolar mode of operation), and as high as 20% if the sensor is exposed to a bipolar field ...
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... Field - Applied Field In this case the sensor is operating on the major hysteresis loop, so the hysteresis shown by the output characteristic of the sensor is relatively large. This is the worst-case hysteresis exhibited by the sensor element. www.nve.com Voltage Output Follows This Output Curve from Positive Saturation Field Back ...
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... Field, Sensor Returns to Zero Along This Line - Applied Field The same small positive field, applied after a positive saturating field, will result in a positive voltage output: - Applied Field www.nve.com Voltage Output After Negative Saturation After returning to zero, a small positive field will ...
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... With this approach, a small applied field to the sensor will result in a bipolar output signal. Furthermore, the slope of the signal characteristic will be the same no matter which curve the sensor is operating on. So, the magnetic sensitivity of the device is the same, no matter how much hysteresis the sensor has. www.nve.com Voltage Output - 92 - ...
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... Sensor hysteresis presents challenges in some applications, but in most cases the sensor elements can be used to advantage despite the hysteresis characteristics. www.nve.com Voltage Output Follows This Output ...
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... This allows use of GMR materials that saturate at higher fields. For example, to sense a field from 0 to 100 Oersteds, NVE deposits a GMR sensor that saturates at a nominal 300 Oersteds and flux concentrators with a magnification factor of three ...
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... AA002-02 Se nsor Characte ristic, 5V Supply -20 -15 GMR M AGNETIC This signal output can be coupled directly into a linear amplifier or a comparator to generate a high level electrical signal proportional to the strength of the magnetic field seen by the sensor. www.nve.com 0.3 0.25 0.2 0.15 0.1 0.05 0 ...
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... GMR Magnetic Gradient Sensors (Gradiometers) The NVE gradiometer is a GMR magnetic field sensor used to detect field gradients between Wheatstone bridge configured resistors. This device is “unshielded” (i.e., it does not employ resistor shields) therefore all four (4) legs of the Wheatstone bridge are active (they respond to changes in field level) ...
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... The following graph shows the output characteristic from a gradiometer as the field gradient is varied across the sensor IC: -400 G RADIOMETER www.nve.com Typical Gradiometer Transfer Function Increasing field -200 0 - resistors -20 -30 -40 -50 Magnetic Field Applied to Resistors RIDGE ENSOR UTPUT - 97 - phone: 952-829-9217 fax: 952-829-9189 Application Notes ...
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... Symbol cgs System Length L φ Flux Flux density B Magnetizing force H Magnetomotive force F µ Permeability in air 0 Conversion factors for between measurement systems can be found in the appendix to this catalog. www.nve.com SI System centimeter (cm) meter (m) maxwell weber (Wb) gauss (G) tesla (T) oersted (Oe) ampere turns/m (At/m) gilbert (Gb) ampere turn (At 4π ...
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... Signal Conditioning Circuits A number of methods exist for pre-amplification of an NVE GMR bridge sensor output. This section shows some representative circuits and compares the relative advantages and disadvantages of some common configurations. The circuits shown were designed for low power and 5V operation. Low noise or high performance applications should be designed with lower noise, higher performance components ...
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... This type of amplifier has two significant limitations in that; 1) the feedback resistors load the output of the NVE bridge sense resistors, and 2) the circuit has a poor common mode rejection (CMRR) if the resistor ratios are not ideally matched. Users of this circuit should be aware of the deficiencies and ensure that the feedback resistors are large compared to the bridge resistor values and that the bridge supply is stable and free from noise and ripple ...
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... Two Op Amp Bridge Amplifier The two op amp circuit shown below reduces the loading of the preamplifier on the NVE bridge outputs but still has a CMRR that is dependent on the ratio of resistor matching. The AC CMRR is also poor in that any delay of the common mode signal through op amp U2 provides a mismatch in the signals being delivered to op amp U3 for cancellation ...
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... The DC transfer function of the circuit is: Vout V 1 ref The symmetrical nature of this configuration also allows for cancellation of common mode errors in amplifiers U2 and U3 if the errors track. www.nve.com +5V C2 0.1uF LMC7101A/NS Vref +5V C3 0.1uF LMC7101A/ ...
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... CMRR as active device matching. Active device matching can be easily controlled on integrated circuits allowing for greatly improved CMRR of instrumentation amplifiers over op amp implementations. Also, the gain-bandwidth product of instrumentation amplifier circuits can be higher than op amp circuits. www.nve.com Use for AC coupling 2 IN- ...
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... The gain of the instrumentation amplifier is the same as before. The hysteresis of the comparator is approximately: ≈ − V 2.5 h +5V C1 0.1uF 8 Vin+ 5 Vout+ 1 Vout- 4 Vin- www.nve.com Neglecting the finite output swing of the comparator. +5V C2 0.1uF 7 2 IN RG1 INA118/BB 8 RG2 RG 5 REF ...
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... For use in low-field applications, the noise of the NVE GMR sensors limits the minimum signal detected. For measuring low fields it is recommended that an AC modulation/demodulation scheme be implemented. The figure below shows a block diagram modulation/demodulation circuit. The phase shifter block is required to account for parasitic phase shift around the loop. ...
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... Use Of GMR Magnetic Field Sensors General Considerations All of NVE’s GMR Magnetic Field sensors have a primary axis of sensitivity. The figure below shows an AAxxx-02 Series GMR Magnetic Field Sensor with a cut away view of the die orientation (not to scale) within an SOIC8 package. S ENSITIVE The flux concentrators on the sensor die gather the magnetic flux along the axis shown and focus it at the GMR bridge resistors in the center of the die ...
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... Z direction and minimum field in the sensitive X direction. M Another means of biasing a GMR Magnetic Field Sensor is to provide a constant magnetic field in the sensitive direction. The result is a sensor biased part way up its output curve shown in the figure below. -30 www.nve.com AGNETIC ...
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... It is important not to bias a gradiometer to a high enough field to saturate the GMR resistors. More information on biasing gradiometers for gear tooth sensor applications is found in the GT Sensor application notes section. www.nve.com Application Notes - 108 - phone: 952-829-9217 fax: 952-829-9189 ...
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... Magnetic encoders generate their own magnetic field, but a gear tooth wheel does not differential sensor used to detect gear teeth, a permanent magnet is required to generate a magnetic bias field. The differential magnetic sensor will then be used to detect variations in the field of the permanent magnet as the gear tooth passes by in close proximity. www.nve.com Application Notes R1 GT Sensor ...
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... Typically, the position of the sensor relative to the magnet is fixed, but there is a variation in the airgap between the sensor and the target gear tooth. This can lead to magnetic conditions that can cause an unstable output. www.nve.com Magnet GMR Sensor Resistors R1, R2 ...
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... Finally, as the airgap changes, the magnetic field at the sensor also changes. So, the magnetic field at the sensor will vary from one installation to the next, and if the gear has runout, wobble, or expands with temperature, the output signal and offset of the sensor element will vary. www.nve.com Direction of Sensitivity Magnet ...
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... NVE recommends about 1.5 mm distance from the back of the sensor to the face of the magnet, in order to keep the flux lines at the sensor element “flexible” and able to follow the gear teeth with relative freedom. This distance can be achieved by putting the sensor on one side of a circuit board, and the magnet on the other ...
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... Also note that the GT Sensor provides one full sine wave output for each magnetic pole. This is double the frequency of a Hall effect sensor, which provides one full sine wave output for each north-south pole pair result, replacing a Hall sensor with a GT sensor doubles the resolution of the output signal. www.nve.com Direction of Sensitivity GMR Sensor Resistors R1, R2 ...
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... NVE offers the following guidelines for using GT Sensors in magnetic encoder applications: 1. Position the sensor as symmetrically as possible with the encoder to minimize offset problems couple the sensor to an amplifier to eliminate any offset issues if zero speed operation is not required zero speed operation is required, NVE’s AKL-Series and DD-Series parts automatically compensate for offset variations and provide a digital output signal ...
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... For digital output applications, NVE’s AKL-Series and DD-Series products provide the most cost effective approach. Both of these products provide two-wire, i.e., current modulated output signals. For many applications, an open collector or digital voltage output signal is desirable. The following two circuits convert a two-wire current modulated signal into an open collector or digital voltage output signal: A KL00x Sensor ...
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... Application examples • Hydraulic/pneumatic pressure cylinder stroke position • Suspension position • Fluid level • Machine tool slide position • Aircraft control-surface position • Vehicle detection www.nve.com (axis of sensitivity (axis of sensitivity) - 116 - phone: 952-829-9217 fax: 952-829-9189 Application Notes ...
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... This application allows for current measurement without breaking or interfering with the circuit of interest. The wire can be located above or below the chip, as long oriented perpendicular to the sensitive axis. A xis o f sensitivity Direction o f current flow S M ENSING AGNETIC www.nve.com Application Notes IELD FROM A URRENT - 117 - phone: 952-829-9217 fax: 952-829-9189 W ARRYING ...
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... M ENSING AGNETIC An Excel spreadsheet is available on NVE’s web site which helps calculate the magnetic field at the sensor from a current carrying trace on the board as shown in the diagram above. Principles of Operation The magnetic field created by the current surrounds the conductor radially. As the magnetic field affects the GMR material in the sensor, a differential output is produced at the out pins of the sensor ...
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... DATA ANALYSIS- One To Ten Amps Currents (1-10 A) were run through the 90 and 60-mil traces found on the PCB in NVE’s Current Sensor Evaluation Kit AG003-01. An AA003-02 sensor was placed over the 90 and 60-mil traces and different levels of DC current were run through the traces. This current and the corresponding output from the sensors are shown in the following graphs ...
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... If the current changes direction, the precision of the output at low currents decreases significantly. The specified error of 0.7% will not be obtained again until the current goes above approximately 2A. This guideline is very rough as applications vary. www.nve.com AA003-02 over 0.060" wide 0.0023" thick trace mV Out = 33.6 ± ...
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... This bias point can be seen as the Y intercept in the figures below. In this way, the output will not be near the natural zero current range, and thus, repeatability is increased. With this configuration an alternating sense current will produce a bipolar output with a DC offset application. www.nve.com Application Notes Initialization of AA003-02 Initial sweep ...
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... The current was swept from zero to 100 mA and back to zero multiple times. In this biased state, the sensor is extremely linear and hysteresis is low. A weighed linear fit shows a -29.19 ± 0.08 mV/A correlation with 8.06V supplied which results in a sensitivity of 3.70 ± 0.01 mV/V/A. www.nve.com 0.0023" thick trace @8.06V mV Out = -29.19 ± 0.08(A) ...
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... Thus showing as the current increases, the output of the sensor decreases. In the same respect, the second graph shows that the field from the current was in the same direction as the biasing field. www.nve.com AA003-02 over seven 0.010" wide 0.0023" thick traces mV Out = 177.74 ± ...
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... The offset specification also affects the output. The offset is the zero current or electrical imbalance of the Wheatstone bridge inside the sensor. The magnetic field of the earth at NVE, is approximately 0. 70-degree angle to the horizon (values will vary depending on geographical location). The effects of this magnetic field should be analyzed in each application ...
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... Biasing the sensor partway up the curve will restore a sinusoidal output with a DC component. Although most of the examples given in this section use the AA003-02 sensor element, any of NVE’s AA-Series, AAH-Series, or AAL-Series analog sensors will function as a current sensor as described above ...
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... General discussion GMR Magnetic Field Sensors can be used for detecting different types of magnetic media. In this situation, NVE defines magnetic media as material that has a distinct magnetic signature. The media is typically a non-magnetic substrate with magnetic material placed the substrate. Typically, GMR sensors are used to “read” the magnetic signature by sweeping the substrate and the sensor past each other ...
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... The long dimension of the flux concentrators should be aligned with the sensitive axis of the NVE sensor. To minimize the gap, the flux concentrators should butt up against the NVE sensor package. Since the effective permeability of the flux concentrators is equal to the concentration factor, material with permeability 100 or more times the concentration factor, will be more than sufficient ...
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... With a magnet placed near the moving bill, the bill is magnetized before passing the sensor. The application’s geometrical requirements, strength of magnet, as well as sensor- bill distance will determine which configuration works the best in each application ...
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... The graph below shows the variation in signal at the sensor as the currency is moved farther away from the GMR sensor element. Close proximity to the sensor is important in order to maximize output signal from the sensor. Characteristic of movin g sensor further -0.02 www.nve.com sensitive direction 0.2 0.4 0.6 ...
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... DC offset contributed by the earth’s field, is not seen at the output. Bipolar output signals are often very useful in currency detection and other magnetic media detection applications result, NVE recommends biasing the sensors in these applications by using a current strap under the sensor to carry a bias current, and therefore bias the sensor higher, on its magnetic operating characteristic ...
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... XXX .012 TYP. .034 (.86) Dimensions: inches (mm) .0256 (.65 Note: MSOP8 Package has thermal power dissipation of 320°C/Watt in free air. Attaching the package to a circuit board improves thermal performance. www.nve.com .154 (3.91) .015 (.381) x 45° .016 (.40) NOM. .020 (.508) .188 (4.77) .061 (1.55) ...
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... Drawing – TDFN SO8 PIN 1 INDEX AREA 4.900 ± 0.20 Note: Dimensions in mm. TDFN SO8 Package has thermal power dissipation of 240°C/Watt in free air. Attaching the package to a circuit board improves thermal performance. www.nve.com 0.80 MAX 0.30 ± 0.05(6x) 0.0-0.05 0.20 REF. 0.75±0. ...
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... Lead-free finishes utilizing p ure tin (Sn) have already been qualified at NVE and are available in most of our products. However, additional lead times are associated with these parts. Since most lead-free solders being used in board assembly environments temperatures than traditional tin-lead solders, higher reflow temperatures may be necessary to form an equivalent solder joint between the component and the PC board ...
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... Recommended Solder Reflow Profile NVE recommends the following soldering profile 300 For leaded (Pb) parts, the peak temperature shown in this profile can be decreased to as low as 230°C. Exceeding 265°C at peak or the time at peak temperature shown in this profile can damage the parts. ...
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... Magnet Data NVE supplies Ceramic 8 magnets in some of our GMR sensor evaluation kits. The characteristics for these magnets are given below: Material Type Maximum Operating Temperature Curie Temperature Temperature Coefficient of Flux Density Maximum Energy Product Residual Induction Coercive Force Ceramic 8 M agnetic Characteristics ...
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... Magnet drawings for the two round disc magnets included in the GT Sensor evaluation kits are given below. These magnets are available from NVE as production parts. Contact NVE for pricing and delivery information. In addition, NVE can have custom magnets built for specific applications in Ceramic 8 or Alnico 8 materials ...
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... Part Numbers and Marking Codes NVE’s part number format consists of two or three letters, then three numbers, a dash, and then two more numbers, and in some cases a final letter. Here is an example: AAH004-00E The meanings of the numbers and letters are defined as follows: ...
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... Some of NVE’s products are delivered in packages that are too small to be marked with the complete part number. In these cases a three-letter code is used to identify the part. The following table provides a cross-reference from part number to marking code: NVE Part Number Code AA004-00 ...
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... The following table provides a cross-reference from marking code to part number: Code NVE Part Number BBB AD021-00 BBC AD022-00 BBD AD023-00 BBF AD024-00 BBG AD005-00 BBH AD004-00 BBJ AD006-00 BBK AD020-00 BBL AD024-10 BBP AAV001-11 BBQ AAV002-11 BDB AD081-00 BDC AD082-00 BDD ...
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... RBP: Reverse Battery Protection. Release Point: The field level which produces a logical change in state from “1” to “0” in NVE’s digital magnetic field sensors ADXXX-XX. Resistor Separation: This is the mean separation between the two pairs of resistors Gradiometer or Differential sensor ...
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... TCR (Temperature Coefficient of Resistance): temperature. Expressed as a percentage per unit temperature change. Voltage Span: The differential output voltage taken from zero to 70% of the saturation field level. www.nve.com The variation of the GMR resistors over - 141 - phone: 952-829-9217 fax: 952-829-9189 ...
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... Conversion Factors To Convert µWb A/cm A kA/m maxwell maxwell mT maxwell volt second volt second Wb 2 Wb/cm 2 Wb/m www.nve.com Into Multiply by 2 maxwell 10 Oe 1.256 Oe 1.256 1.256 1 (when µ Wb/ Wb/in 6.452 Wb 0.796 Oe 1.256 µ volt second gamma (γ) 1 A/cm 7.962 x 10 A/m 7.962 x 10 kA/m 7 ...
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... Starting as a research and development only company in 1989, NVE has consistently discovered, developed, and patented manufacturable GMR materials and products over the last 13 years. NVE is now recognized as the world leader in GMR technology and investments in NVE from companies such as Motorola and Cypress Semiconductor underscore this leadership. ...