Circuit model of Hall magnetic sensor and construction method of its simulation model

Abstract

The present invention provides a circuit model and simulation model construction method of a Hall magnetic sensor, which simulates the P on the surface of the Hall magnetic sensor by introducing a diode unit into the circuit model. + The parasitic diode between the doped area and the working area is obtained, and the model parameter curve of the parasitic diode between the doped area and the working area on the surface of the Hall magnetic sensor, the resistance parameters of the resistance unit, the saturation effect parameters of the circuit model, and the sensitivity fitting parameters of the Hall magnetic sensor are obtained; according to the model parameter curve, resistance parameters, saturation effect parameters and sensitivity fitting parameters of the parasitic diode, a simulation model corresponding to the circuit model of the Hall magnetic sensor is established, and the simulation of the leakage phenomenon and current saturation phenomenon of the Hall magnetic sensor is realized, thereby improving the simulation accuracy of the Hall magnetic sensor.

Description

Technical Field

[0001] The present invention relates to the field of simulation of Hall effect magnetic sensors, and in particular to a circuit model of a Hall effect magnetic sensor and a method for constructing the simulation model thereof. Background Art

[0002] A Hall effect magnetic field sensor is a device that uses the Hall effect principle to achieve magneto-electric conversion and is commonly used for magnetic field detection. Using CMOS technology, the Hall effect magnetic sensor and control circuit can be integrated on the same chip, reducing manufacturing costs and enabling device miniaturization.

[0003] To facilitate the mixed simulation of Hall effect magnetic sensors and signal processing circuits and improve the accuracy of circuit-level simulation, an accurate Hall effect magnetic sensor simulation model is usually extracted as the circuit's signal source input. However, the accuracy of existing Hall effect magnetic sensor simulation models is not high.

[0004] Therefore, how to improve the simulation accuracy of Hall magnetic sensors has become a technical problem that the industry urgently needs to solve. Summary of the Invention

[0005] The present invention provides a circuit model of a Hall magnetic sensor and a simulation model construction method thereof, so as to improve the simulation accuracy of the Hall magnetic sensor.

[0006] According to a first aspect of the present invention, an embodiment of the present invention provides a circuit model of a Hall magnetic sensor, the circuit model including:

[0007] There are four inner ring resistance units, and the four inner ring resistance units are symmetrically distributed around the center; a first end of each inner ring resistance unit is connected to a common terminal, and a second end thereof is connected to a corresponding internal port, so as to form a cross-shaped bridge;

[0008] There are four outer ring resistance units, each outer ring resistance unit is arranged between two adjacent internal ports in a one-to-one correspondence, and two ends of each outer ring resistance unit are respectively connected to the two adjacent internal ports;

[0009] There are four diode units, the cathode of each diode unit is connected to the corresponding internal port in a one-to-one correspondence, and the anode of each diode unit is grounded;

[0010] There are four current-controlled voltage sources, each of which is connected between a corresponding internal port and an external port in a one-to-one correspondence; wherein the four external ports correspond one-to-one to the four external ports of the Hall magnetic sensor.

[0011] According to a second aspect of the present invention, a simulation model construction method is provided, which can use the circuit model of the Hall effect magnetic sensor described in the first aspect for simulation, and the method includes:

[0012] Obtaining a model parameter curve of a diode unit, a resistance parameter of a resistance unit, a saturation effect parameter of the circuit model, and a sensitivity fitting parameter of the Hall magnetic sensor in a circuit model of the Hall magnetic sensor;

[0013] Based on the model parameter curve of the diode unit, a model parameter curve of the parasitic diode between the surface doping region and the working region of the Hall magnetic sensor is obtained;

[0014] A simulation model corresponding to the circuit model of the Hall magnetic sensor is established according to the model parameter curve of the parasitic diode, the resistance parameter, the saturation effect parameter, and the sensitivity fitting parameter.

[0015] Optionally, the method for obtaining a model parameter curve of a parasitic diode between a surface doped region and a working region of the Hall magnetic sensor based on a model parameter curve of the diode unit includes:

[0016] A standard diode model is used as the diode model of the diode unit, and four internal ports are connected to the negative measurement terminal, and the positive electrode of the diode unit is connected to the positive measurement terminal;

[0017] measuring the voltage-current curves of the positive electrode measurement terminal and the negative electrode measurement terminal as the DC parameter curve of the diode unit to obtain the DC parameter curve of the parasitic diode; and

[0018] The voltage-capacitance curves of the positive electrode measurement terminal and the negative electrode measurement terminal are measured as the AC parameter curve of the diode unit to obtain the AC parameter curve of the parasitic diode.

[0019] Optionally, the method for obtaining the resistance parameter of the resistance unit includes:

[0020] Keep the ambient magnetic field strength at zero and select two of the four external ports as measurement ports;

[0021] measuring a first current-voltage curve between two different external ports at a first temperature;

[0022] Fitting first current-voltage curves corresponding to different measurement ports to extract model parameters of the resistance unit at the first temperature;

[0023] measuring second current-voltage curves between different pairs of external ports, wherein each second current-voltage curve between the two pairs of external ports includes second current-voltage curves at multiple temperatures;

[0024] Fitting second current-voltage curves at different temperatures based on the model parameters to extract temperature parameters of the resistor unit;

[0025] Based on the model parameters and the temperature parameters, resistance parameters of the resistance unit in the circuit model are obtained.

[0026] Optionally, the functional relationship of the resistance parameter is:

[0027]

[0028] Among them, R in1 Indicates the actual resistance value of the inner circle resistance unit, R out1 Indicates the actual resistance value of the outer ring resistance unit, R shi represents the resistance value of the inner ring resistance unit at the first temperature and without current, R sho A represents the resistance value of the outer ring resistance unit at the first temperature and without current, and the resistance value at room temperature and without current, i 、B i 、A o 、B o is the model parameter of the resistance unit, where A i Represents the primary current effect parameter of the inner ring resistance unit, B i Represents the secondary current effect parameter of the inner ring resistance unit, A o Indicates the primary current effect parameter of the outer ring resistance unit, B o It represents the secondary current effect parameter of the outer ring resistance unit, tc1 and tc2 represent the temperature parameters of the resistance unit, wherein tc1 represents the primary temperature parameter of the inner ring resistance unit or the outer ring resistance unit, tc2 represents the secondary temperature parameter of the inner ring resistance unit or the outer ring resistance unit, T represents temperature, and I represents applied current.

[0029] Optionally, the method for obtaining the saturation effect parameter of the circuit model includes:

[0030] Keep the ambient magnetic field strength at zero and select two of the four external ports as measurement ports;

[0031] Measuring a saturation voltage threshold between different pairs of external ports when the measured current reaches a saturation current;

[0032] Measure the saturation current-voltage curves between different pairs of external ports at saturation current;

[0033] A saturation effect parameter of the circuit model is obtained according to the saturation voltage threshold and the saturation current-voltage curve.

[0034] Optionally, the functional relationship of the saturation effect parameter is:

[0035]

[0036]

[0037] Among them, R in2 Indicates the actual resistance value of the inner circle resistance unit under current saturation conditions, R out2 Indicates the actual resistance value of the outer ring resistance unit under current saturation conditions, K i , K o , Nsati, Nsato are the saturation effect parameters of the circuit model, K i is the fitting parameter of the inner circle resistance unit, K o is the fitting parameter of the outer ring resistance unit, Nsati is the voltage coefficient of the inner ring resistance unit, Nsato is the voltage coefficient of the outer ring resistance unit, Vsat represents the saturation voltage threshold, and V represents the applied voltage greater than the saturation voltage threshold.

[0038] Optionally, obtaining the sensitivity fitting parameters of the Hall effect magnetic sensor includes:

[0039] Select two external ports on any diagonal line of the four external ports of the Hall effect magnetic sensor as input ports, and the other two external ports as measurement ports;

[0040] At a first set temperature, measuring a first voltage-magnetic field curve of the output voltage and the ambient magnetic field strength corresponding to different input currents;

[0041] Fitting first voltage-magnetic field curves corresponding to different input currents to extract initial sensitivity fitting parameters of the Hall magnetic sensor;

[0042] Under the first set current, measuring the second voltage-magnetic field curve corresponding to the output voltage and the ambient magnetic field strength at different temperatures;

[0043] Fitting the second voltage-magnetic field curve corresponding to different temperatures to extract the sensitivity temperature fitting parameters;

[0044] The sensitivity fitting parameters of the Hall magnetic sensor are obtained according to the sensitivity temperature fitting parameters and the sensitivity initial fitting parameters.

[0045] Optionally, the temperature function relationship of the sensitivity fitting parameter is:

[0046]

[0047]

[0048] Among them, S 01 , S 02 represents the initial sensitivity fitting parameter, S 01 is the initial fitting parameter value of the first sensitivity, S 02 represents the second sensitivity initial fitting parameter value, stc1 and stc1 represent the sensitivity temperature fitting parameters, stc1 represents the sensitivity temperature first-order fitting parameter, and stc1 represents the sensitivity temperature second-order fitting parameter.

[0049] Optionally, the simulation model corresponding to the circuit model of the Hall magnetic sensor is:

[0050]

[0051] Among them, V h is the output voltage of the Hall magnetic sensor, I a is the input current, B is the ambient magnetic field strength, S1 and S2 are sensitivity fitting parameters, S1 is the first sensitivity fitting parameter of the Hall magnetic sensor, and S2 is the second sensitivity fitting parameter of the Hall magnetic sensor.

[0052] Compared with the prior art, the technical solution of the embodiment of the present invention has the following beneficial effects:

[0053] The present invention provides a circuit model and simulation model construction method of a Hall magnetic sensor, which simulates the P on the surface of the Hall magnetic sensor by introducing a diode unit into the circuit model. + The parasitic diode between the doped area and the working area is obtained, and the model parameter curve of the parasitic diode between the doped area and the working area on the surface of the Hall magnetic sensor, the resistance parameters of the resistance unit, the saturation effect parameters of the circuit model, and the sensitivity fitting parameters of the Hall magnetic sensor are obtained; according to the model parameter curve, resistance parameters, saturation effect parameters and sensitivity fitting parameters of the parasitic diode, a simulation model corresponding to the circuit model of the Hall magnetic sensor is established, and the simulation of the leakage phenomenon and current saturation phenomenon of the Hall magnetic sensor is realized, thereby improving the simulation accuracy of the Hall magnetic sensor.

[0054] Furthermore, the present invention considers the nonlinear effect of the sensitivity fitting parameters and the temperature effect of the sensitivity fitting parameters when establishing a simulation model corresponding to the circuit model of the Hall magnetic sensor, thereby improving the simulation accuracy of the Hall magnetic sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0056] Figure 1 Schematic diagram of the device structure of a Hall magnetic sensor in an example;

[0057] Figure 2 Schematic diagram of the structure of a circuit model of a Hall magnetic sensor in one embodiment;

[0058] Figure 3 A schematic flow chart of a simulation model construction method in one embodiment;

[0059] Figure 4-11 A schematic diagram of measurement curves in the process of providing a simulation model construction method in one embodiment of the present invention. DETAILED DESCRIPTION

[0060] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0061] The terms "first," "second," "third," "fourth," and so on (if any) in the description and claims of the present invention and in the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in orders other than those illustrated or described herein. In addition, the terms "including" and "having," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus that includes a series of steps or elements is not necessarily limited to those steps or elements explicitly listed, but may include other steps or elements not explicitly listed or inherent to such processes, methods, products, or apparatuses.

[0062] The technical solution of the present invention is described in detail below with reference to specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0063] As described in the background art, various existing simulation models of Hall effect magnetic sensors have the problem of low accuracy. The applicant has conducted in-depth research on the corresponding reasons, which are described in detail as follows:

[0064] Please refer to Figure 1 , Figure 1 is a structural diagram of the Hall magnetic sensor; Figure 1 As shown, the Hall magnetic sensor forms an N well on a P-type substrate 10 as a working area 20 of the integrated Hall magnetic sensor, and uses a deep trench 30 to isolate it from other devices. + Ion implantation is performed to form four external ports; and P is performed on the surface of the working area 20. + Ion implantation forms a shallower P-type layer 40, wherein the P-type layer 40 is grounded during operation. Specifically, the four external ports of the Hall magnetic sensor correspond to Figure 1 The first external port A, the second external port B, the third external port C and the fourth external port D in the .

[0065] Among them, the P-type layer 40 and the working area 20 form a PN junction (parasitic diode). Since the P-type layer 40 is grounded, the depletion layer thickness of the parasitic diode will change with the current passing through the device, and the resistance and capacitance values ​​of the Hall magnetic sensor will also change with the current passing through. In addition, when the current passing through is large enough, the current will reach saturation, thereby generating a current saturation effect. When the reverse current passing through is large enough, the reverse voltage on the parasitic diode is large, and the parasitic diode will leak. The current saturation effect and leakage phenomenon will affect the simulation accuracy of the Hall magnetic sensor.

[0066] In view of this, the present invention provides a circuit model of a Hall magnetic sensor, which may include:

[0067] There are four inner ring resistance units, and the four inner ring resistance units are symmetrically distributed around the center; a first end of each inner ring resistance unit is connected to a common terminal, and a second end of each inner ring resistance unit is connected to a corresponding internal port, so as to form a cross-shaped bridge;

[0068] There are four outer ring resistor units, each of which is disposed between two adjacent internal ports in a one-to-one correspondence, and each of which has two ends connected to the two adjacent internal ports respectively;

[0069] There are four diode units, the cathode of each diode unit is connected to the corresponding internal port, and the anode of each diode unit is grounded;

[0070] There are four current-controlled voltage sources, each of which is coupled between a corresponding internal port and an external port, and the external port serves as an external port of the Hall magnetic sensor.

[0071] The present invention utilizes the above-mentioned circuit model to construct a simulation model of the circuit model of the Hall magnetic sensor. The method may include: obtaining a model parameter curve of a diode unit, a resistance parameter of a resistance unit, a saturation effect parameter of the circuit model, and a sensitivity fitting parameter of the Hall magnetic sensor in the circuit model of the Hall magnetic sensor; based on the model parameter curve of the diode unit, obtaining a model parameter curve of a parasitic diode between a surface doped region and a working region of the Hall magnetic sensor; and establishing a simulation model corresponding to the circuit model of the Hall magnetic sensor based on the model parameter curve of the parasitic diode, the resistance parameter, the saturation effect parameter, and the sensitivity fitting parameter.

[0072] In the above embodiment, the diode unit is introduced into the circuit model to simulate the P on the surface of the Hall magnetic sensor. + The parasitic diode between the doped area and the working area is obtained, and the model parameter curve of the parasitic diode between the doped area and the working area on the surface of the Hall magnetic sensor, the resistance parameters of the resistance unit, the saturation effect parameters of the circuit model, and the sensitivity fitting parameters of the Hall magnetic sensor are obtained; according to the model parameter curve, resistance parameters, saturation effect parameters and sensitivity fitting parameters of the parasitic diode, a simulation model corresponding to the circuit model of the Hall magnetic sensor is established, and the simulation of the leakage phenomenon and current saturation phenomenon of the Hall magnetic sensor is realized, thereby improving the simulation accuracy of the Hall magnetic sensor.

[0073] In order to make the above-mentioned objects, features and beneficial effects of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0074] Please refer to Figure 2 , a schematic diagram of the circuit model structure of a Hall magnetic sensor provided by an embodiment of the present invention, the circuit model may include:

[0075] Inner ring resistance unit R in , the inner circle resistance unit R in The number is four, four inner circle resistance units R in The distribution is symmetrical around the center; each inner circle resistance unit R in The first ends of the terminals are connected to the common terminal O, and the second ends thereof are connected to the corresponding internal ports N1-N4, respectively, to form a cross bridge.

[0076] As an example, the inner circle resistance unit R inAs a single resistor, of course, it should be understood that the present invention is not limited to this, the inner circle resistor unit R in It is also possible to connect two or more resistors in series, two or more resistors in parallel, or multiple resistors in series and parallel, as long as the four inner circle resistor units R in Just the same.

[0077] Outer ring resistance unit R out , the outer ring resistance unit R out The number is four, each outer ring resistance unit R out One-to-one correspondence is set between two adjacent internal ports, and each outer ring resistor unit R out The two ends of the connector are connected to two adjacent internal ports respectively.

[0078] As an example, the outer ring resistance unit R out It is a single resistor. Of course, it should be understood that the present invention is not limited to this. The outer ring resistor unit R out It is also possible to connect two or more resistors in series, two or more resistors in parallel, or multiple resistors in series and parallel as a combination, as long as the four outer circle resistor units are the same.

[0079] The diode units D are four in number, the cathode of each diode unit D is connected to the corresponding internal port, and the anode of each diode unit D is grounded.

[0080] In this embodiment, a standard diode model may be used as the diode unit model.

[0081] The current-controlled voltage source V is four in number, and each current-controlled voltage source V is coupled between a corresponding internal port N1 - N4 and an external port ad, where the external port serves as an external port of the Hall magnetic sensor.

[0082] As an embodiment of the present invention, the simulation model construction method provided in the embodiment of the present invention may include:

[0083] Step 1: Obtain a model parameter curve of a diode unit in a circuit model of the Hall magnetic sensor, a resistance parameter of a resistance unit, a saturation effect parameter of the circuit model, and a sensitivity fitting parameter of the Hall magnetic sensor.

[0084] Step 2: Based on the model parameter curve of the diode unit, a model parameter curve of the parasitic diode between the surface doping region and the working region of the Hall magnetic sensor is obtained.

[0085] Step three: establishing a simulation model corresponding to the circuit model of the Hall magnetic sensor according to the model parameter curve of the parasitic diode, the resistance parameter, the saturation effect parameter, and the sensitivity fitting parameter.

[0086] There is no order between steps 1 to 3. For another implementation, please refer to Figure 3 , and combined with reference Figure 1 、 Figure 2 as well as Figure 4-11 The simulation model construction method provided by the embodiment of the present invention may include:

[0087] S1: When the ambient magnetic field intensity is zero, a model parameter curve of a parasitic diode between a surface doping region and a working region of the Hall magnetic sensor is obtained based on a model parameter curve of the diode unit.

[0088] As a specific embodiment, a standard diode model is used as the model of the diode unit in step S1; step S1 may include:

[0089] S11: Connect the four internal ports to the negative measurement terminal, and connect the positive electrode of the diode unit to the positive measurement terminal.

[0090] S12: measuring the voltage-current curves of the positive electrode measurement terminal and the negative electrode measurement terminal to obtain a DC parameter curve of the parasitic diode.

[0091] S13: measuring the voltage-capacitance curves of the positive electrode measurement terminal and the negative electrode measurement terminal to obtain an AC parameter curve of the parasitic diode.

[0092] In one example, step S11 may include: applying a preset voltage value sequence to the four diode units in the Hall magnetic sensor circuit model in sequence, and measuring a current value sequence corresponding to the voltage value sequence at the positive measurement end and the negative measurement end; based on the preset voltage value sequence and the measured current value sequence, obtaining a DC parameter curve of the diode unit.

[0093] As an example, the method for obtaining a DC parameter curve of a parasitic diode may include: fitting the DC parameter curve of the diode unit using a least squares method to obtain the DC parameter curve of the parasitic diode.

[0094] Please refer to Figure 4 , Figure 4 The DC parameter curve of the diode unit with a voltage value sequence in the range of (-1.50, 1.50) is shown in FIG. Figure 4 The abscissa VJ can be understood as the applied voltage of the diode unit, Figure 4The ordinate Ii can be understood as the measured current of the diode unit.

[0095] Please refer to Figure 5 , Figure 5 The DC parameter curve of the diode unit with a voltage value sequence in the range of (0, -40) is shown. Figure 5 The abscissa can be understood as the applied voltage of the diode unit, Figure 5 The ordinate can be understood as the measured current of the diode unit.

[0096] Among them, the aforementioned voltage value sequence can be understood as voltages of different values, and the current value sequence can be understood as currents of different values. The sequences below are understood similarly and will not be repeated here.

[0097] As an example, step S12 may include:

[0098] A preset voltage value sequence is sequentially applied to the four diode units in the Hall magnetic sensor circuit model, and a capacitance value sequence corresponding to the voltage value sequence is measured at the positive measurement end and the negative measurement end.

[0099] According to the preset voltage value sequence and the corresponding capacitance value sequence, an AC parameter curve of the diode unit is obtained.

[0100] In one example, the method for obtaining the AC parameter curve of the parasitic diode includes: fitting the AC parameter curve of the diode unit to obtain the AC parameter curve of the parasitic diode.

[0101] Please refer to Figure 6 , Figure 6 is the AC parameter curve of the diode unit, Figure 6 The abscissa is the measured voltage of the diode unit, Figure 6 The ordinate is the measured capacitance of the diode unit.

[0102] S2: Obtaining model parameters of the resistance unit in the circuit model of the Hall magnetic sensor when the ambient magnetic field intensity is zero.

[0103] In an optional implementation, step S2 may include:

[0104] S21: Keeping the ambient magnetic field intensity at zero, measuring first current-voltage curves between different pairs of external ports at a first temperature.

[0105] As an example, the first temperature is 25° C., but it should be understood that the present invention is not limited thereto.

[0106] As an embodiment, step S21 may include:

[0107] At a first temperature, a first current value sequence is applied to different pairs of external ports, and a corresponding first voltage value sequence is measured at the corresponding measurement port. Then, a first current-voltage curve is obtained based on the first current value sequence and the corresponding first voltage value sequence.

[0108] Specifically, please refer to Figure 2 For example, the first external port a and the third external port c are selected as measurement ports, currents of different magnitudes are applied to the first external port a and the third external port c, and the voltages at the two external ports under each current are measured to obtain first current-voltage curves of the first external port a and the third external port c. Furthermore, to eliminate measurement errors, the second external port b and the fourth external port d are further selected as measurement ports, and similar measurements are performed to obtain first current-voltage curves of the second external port b and the fourth external port d. Of course, it should be understood that the present invention is not limited to this, and those skilled in the art may also select any two different external ports as measurement ports as needed.

[0109] S22: Fitting first current-voltage curves corresponding to different measurement ports to extract model parameters of the resistance unit at the first temperature.

[0110] Specifically, the model parameters of the resistance unit at the first temperature can be extracted by fitting the first current-voltage curves obtained at the first temperature using the least square method.

[0111] S23: measuring second current-voltage curves between different pairs of external ports, where each second current-voltage curve between two pairs of external ports includes second current-voltage curves at multiple temperatures.

[0112] As an embodiment, the specific measurement method of step S23 is similar to that of step S21, with the only difference being that for the same group of measurement ports, the temperature needs to be changed to obtain the second current-voltage curves at multiple temperatures.

[0113] S24: Fitting second current-voltage curves at different temperatures based on the model parameters to extract temperature parameters of the resistance unit.

[0114] Specifically, since the model parameters at the first temperature have been extracted in step S22, the model parameters can be combined with the least square method to fit each second current-voltage curve to extract the temperature parameters of the resistance unit.

[0115] Please refer to Figure 7 , and combined with reference Figure 2 , Figure 7The relationship curve between the applied current and the measured voltage of the circuit model of the Hall magnetic sensor is shown in the figure below, when the first external port a and the third external port c are used as measurement ports and the ambient magnetic field intensity is 0. Figure 7 The horizontal axis can be understood as the applied current of the Hall magnetic sensor when the ambient magnetic field strength is 0. Figure 7 The vertical axis can be understood as the measured voltage of the Hall magnetic sensor when the ambient magnetic field strength is 0.

[0116] Please refer to Figure 8 , Figure 8 A relationship curve between the applied current and the measured voltage of the circuit model of the Hall magnetic sensor is shown when the first external port a and the third external port c are used as measurement ports and the ambient magnetic field intensity is 0. Figure 8 The horizontal axis can be understood as the applied current of the Hall magnetic sensor when the ambient magnetic field intensity is 0. Figure 8 The vertical axis can be understood as the measured voltage of the Hall magnetic sensor when the ambient magnetic field strength is 0.

[0117] S25: Obtaining resistance model parameters in the circuit model based on the first model parameters and the temperature parameters.

[0118] In a specific embodiment, the functional relationship of the resistance parameter is:

[0119]

[0120] Among them, R in1 Indicates the actual resistance value of the inner circle resistance unit, R out1 Indicates the actual resistance value of the outer ring resistance unit, R shi represents the resistance value of the inner ring resistance unit at the first temperature and without current, R sho A represents the resistance value of the outer ring resistance unit at the first temperature and without current, and the resistance value at room temperature and without current, i 、B i 、A o 、B o is the model parameter of the resistance unit, where A i Represents the primary current effect parameter of the inner ring resistance unit, B i Represents the secondary current effect parameter of the inner ring resistance unit, A o Indicates the primary current effect parameter of the outer ring resistance unit, B oIt represents the secondary current effect parameter of the outer ring resistance unit, tc1 and tc2 represent the temperature parameters of the resistance unit, wherein tc1 represents the primary temperature parameter of the inner ring resistance unit or the outer ring resistance unit, tc2 represents the secondary temperature parameter of the inner ring resistance unit or the outer ring resistance unit, T represents temperature, and I represents applied current.

[0121] S3: Obtaining saturation effect parameters of the circuit model when the ambient magnetic field intensity is zero.

[0122] The saturation effect parameter refers to a model parameter of the simulation model when the measurement current used to characterize the circuit model reaches the saturation current in the simulation model.

[0123] In a specific implementation, step S3 may include:

[0124] S31: Keep the ambient magnetic field strength at zero and select two of the four external ports as measurement ports.

[0125] S32: measuring a saturation voltage threshold between two different external ports when the measured current reaches a saturation current.

[0126] S33: Measure the saturation current-voltage curves between different pairs of external ports under saturation current.

[0127] As an embodiment, step S33 may include: keeping the ambient magnetic field intensity at zero and keeping the measurement temperature unchanged, selecting two of the four external ports as measurement ports, applying a third voltage value sequence greater than the saturation voltage threshold to the measurement port, and measuring the third current value sequence of the corresponding measurement port; obtaining a saturation current-voltage curve under saturation current based on the third voltage value sequence and the corresponding third current value sequence.

[0128] S34: Obtaining a saturation effect parameter of the circuit model according to the saturation voltage threshold and the saturation current-voltage curve.

[0129] As an example, step S34 may include: fitting the saturation current-voltage curve under the saturation current using a least squares method to extract the saturation effect parameters of the circuit model.

[0130] Please refer to Figure 9 , Figure 9 The current-voltage curve before the measured current reaches saturation, and the relationship curve between the applied voltage and the measured current of the circuit model of the Hall magnetic sensor combined with the saturated current-voltage curve; Figure 9 The horizontal axis can be understood as the applied voltage, Figure 9 The vertical axis can be understood as the measured current.

[0131] In a specific embodiment, the functional relationship of the saturation effect parameter can be expressed as:

[0132]

[0133]

[0134] Among them, R in2 Indicates the actual resistance value of the inner circle resistance unit under current saturation conditions, R out2 Indicates the actual resistance value of the outer ring resistance unit under current saturation conditions, K i , K o , Nsati, Nsato are the saturation effect parameters of the circuit model, K i is the fitting parameter of the inner circle resistance unit, K o is the fitting parameter of the outer ring resistance unit, Nsati is the voltage coefficient of the inner ring resistance unit, Nsato is the voltage coefficient of the outer ring resistance unit, Vsat represents the saturation voltage threshold, and V represents the applied voltage greater than the saturation voltage threshold.

[0135] S4: Obtain sensitivity fitting parameters of the Hall magnetic sensor.

[0136] In one embodiment, step S4 may include:

[0137] S41: Select two external ports on any diagonal line among the four external ports of the Hall magnetic sensor as input ports, and the other two external ports as measurement ports.

[0138] As an example, see Figure 1 , the external port A and the external port C are selected as input ports. In this case, the external port B and the external port D are measurement ports. Of course, it should be understood that the present invention is not limited to this.

[0139] S42: Under a first set temperature, measuring first voltage-magnetic field curves of output voltage and ambient magnetic field strength corresponding to different input currents.

[0140] For example, the first set temperature is 25° C., but the present invention is not limited thereto.

[0141] As an example, step S42 may include: applying an ambient magnetic field value sequence to the Hall magnetic sensor at a first set temperature, measuring the output voltage value sequence of the measuring port, and obtaining a first voltage-magnetic field curve of the output voltage and the ambient magnetic field strength; and obtaining the first voltage-magnetic field curve under different input currents.

[0142] Please refer to Figure 10 , Figure 10are the second voltage magnetic field curves corresponding to different input currents at the first set temperature, Figure 10 The horizontal axis Vmfld can be understood as the voltage expression of the ambient magnetic field strength; Figure 10 The vertical axis can be understood as the output voltage.

[0143] S43: Fitting first voltage-magnetic field curves corresponding to different input currents to extract initial sensitivity fitting parameters of the Hall magnetic sensor.

[0144] S44: Under the first set current, measuring second voltage-magnetic field curves corresponding to the output voltage and the ambient magnetic field strength at different temperatures.

[0145] As an example, step S44 may include: inputting a first set current into the input port, applying an ambient magnetic field value sequence to the Hall magnetic sensor, measuring the output voltage value sequence of the measurement port, and obtaining a second voltage-magnetic field curve; and obtaining the second voltage-magnetic field curve at different temperatures.

[0146] Please refer to Figure 11 , Figure 11 The second voltage magnetic field curve corresponding to the input current of the first set current and different temperatures is shown in the figure. Figure 11 The horizontal axis Vmfld can be understood as the voltage expression of the ambient magnetic field strength; Figure 11 The vertical axis can be understood as the output voltage.

[0147] S45: Fitting the second voltage-magnetic field curves corresponding to different temperatures, and extracting sensitivity temperature fitting parameters.

[0148] S46: Obtaining a sensitivity fitting parameter of the Hall magnetic sensor according to the sensitivity temperature fitting parameter and the initial sensitivity fitting parameter.

[0149] As a specific implementation, the temperature function relationship of the sensitivity fitting parameter can be expressed as:

[0150]

[0151]

[0152] Among them, S 01 , S 02 represents the initial sensitivity fitting parameter, S 01 is the initial fitting parameter value of the first sensitivity, S 02 represents the second sensitivity initial fitting parameter value, stc1 and stc1 represent the sensitivity temperature fitting parameters, stc1 represents the sensitivity temperature first-order fitting parameter, and stc1 represents the sensitivity temperature second-order fitting parameter.

[0153] S5: Establishing a simulation model corresponding to the circuit model of the Hall magnetic sensor according to the model parameter curve of the parasitic diode, the resistance parameter, the saturation effect parameter, and the sensitivity fitting parameter.

[0154] In a specific embodiment, the simulation model corresponding to the circuit model of the Hall magnetic sensor can be expressed as:

[0155]

[0156] Among them, V h is the output voltage of the Hall magnetic sensor, I a is the input current, B is the ambient magnetic field strength, S1 and S2 are sensitivity fitting parameters, S1 is the first sensitivity fitting parameter of the Hall magnetic sensor, and S2 is the second sensitivity fitting parameter of the Hall magnetic sensor.

[0157] In summary, the present invention provides a circuit model and simulation model construction of a Hall magnetic sensor, which simulates the P on the surface of the Hall magnetic sensor by introducing a diode unit into the circuit model. + The parasitic diode between the doped area and the working area is obtained, and the model parameter curve of the parasitic diode between the doped area and the working area on the surface of the Hall magnetic sensor, the resistance parameters of the resistance unit, the saturation effect parameters of the circuit model, and the sensitivity fitting parameters of the Hall magnetic sensor are obtained; according to the model parameter curve, resistance parameters, saturation effect parameters and sensitivity fitting parameters of the parasitic diode, a simulation model corresponding to the circuit model of the Hall magnetic sensor is established, and the simulation of the leakage phenomenon and current saturation phenomenon of the Hall magnetic sensor is realized, thereby improving the simulation accuracy of the Hall magnetic sensor.

[0158] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the scope defined by the claims.

Claims

1. A simulation model construction method, characterized in that: The simulation model is a simulation model corresponding to a circuit model of a Hall magnetic sensor, and the circuit model includes: There are four inner ring resistance units, and the four inner ring resistance units are symmetrically distributed around the center; a first end of each inner ring resistance unit is connected to a common terminal, and a second end of each inner ring resistance unit is connected to a corresponding internal port, so as to form a cross-shaped bridge; There are four outer ring resistor units, each of which is disposed between two adjacent internal ports in a one-to-one correspondence, and each of which has two ends connected to the two adjacent internal ports respectively; There are four diode units, the cathode of each diode unit is connected to the corresponding internal port, and the anode of each diode unit is grounded; a current-controlled voltage source, wherein the number of the current-controlled voltage sources is four, and each current-controlled voltage source is coupled between a corresponding internal port and an external port, wherein the external port serves as an external connection port of the Hall magnetic sensor; The method comprises: Obtaining a model parameter curve of a diode unit in a circuit model of the Hall magnetic sensor, a resistance parameter of a resistance unit, a saturation effect parameter of the circuit model, and a sensitivity fitting parameter of the Hall magnetic sensor, wherein the saturation effect parameter is a model parameter when a measured current of the circuit model reaches a saturation current; Based on the model parameter curve of the diode unit, a model parameter curve of the parasitic diode between the surface doping region and the working region of the Hall magnetic sensor is obtained; A simulation model corresponding to the circuit model of the Hall magnetic sensor is established according to the model parameter curve of the parasitic diode, the resistance parameter, the saturation effect parameter, and the sensitivity fitting parameter.

2. The simulation model construction method according to claim 1, wherein: The method for obtaining a model parameter curve of a parasitic diode between a surface doped region and a working region of the Hall magnetic sensor based on a model parameter curve of the diode unit includes: A standard diode model is used as the diode model of the diode unit, and four internal ports are connected to the negative measurement terminal, and the positive electrode of the diode unit is connected to the positive measurement terminal; measuring the voltage-current curves of the positive electrode measurement terminal and the negative electrode measurement terminal as the DC parameter curve of the diode unit to obtain the DC parameter curve of the parasitic diode; and The voltage-capacitance curves of the positive electrode measurement terminal and the negative electrode measurement terminal are measured as the AC parameter curve of the diode unit to obtain the AC parameter curve of the parasitic diode.

3. The simulation model construction method according to claim 1, wherein: The method for obtaining the resistance parameter of a resistance unit includes: Keep the ambient magnetic field strength at zero and select two of the four external ports as measurement ports; measuring a first current-voltage curve between two different external ports at a first temperature; Fitting first current-voltage curves corresponding to different measurement ports to extract model parameters of the resistance unit at the first temperature; measuring second current-voltage curves between different pairs of external ports, wherein each second current-voltage curve between the two pairs of external ports includes second current-voltage curves at multiple temperatures; Fitting second current-voltage curves at different temperatures based on the model parameters to extract temperature parameters of the resistor unit; Based on the model parameters and the temperature parameters, resistance parameters of the resistance unit in the circuit model are obtained.

4. The simulation model construction method according to claim 3, wherein: The functional relationship of the resistance parameters is: Among them, R in1 Indicates the actual resistance value of the inner circle resistance unit, R out1 Indicates the actual resistance value of the outer ring resistance unit, R shi represents the resistance value of the inner ring resistance unit at the first temperature and without current, R sho A represents the resistance value of the outer ring resistance unit at the first temperature and without current, and the resistance value at room temperature and without current, i 、B i 、A o 、B o is the model parameter of the resistance unit, where A i Represents the primary current effect parameter of the inner ring resistance unit, B i Represents the secondary current effect parameter of the inner ring resistance unit, A o Indicates the primary current effect parameter of the outer ring resistance unit, B o Represents the secondary current effect parameter of the outer ring resistance unit, tc1 and tc2 represent the temperature parameters of the resistance unit, wherein tc1 represents the primary temperature parameter of the inner ring resistance unit or the outer ring resistance unit, and tc2 represents the secondary temperature parameter of the inner ring resistance unit or the outer ring resistance unit. T Indicates temperature, I Indicates applied current.

5. The simulation model construction method according to claim 1, wherein: The method for obtaining the saturation effect parameter of the circuit model includes: Keep the ambient magnetic field strength at zero and select two of the four external ports as measurement ports; Measuring a saturation voltage threshold between different pairs of external ports when the measured current reaches a saturation current; Measure the saturation current-voltage curves between different pairs of external ports at saturation current; A saturation effect parameter of the circuit model is obtained according to the saturation voltage threshold and the saturation current-voltage curve.

6. The simulation model construction method according to claim 5, wherein: The functional relationship of the saturation effect parameter is: in, R in2 Indicates the actual resistance value of the inner ring resistance unit under current saturation conditions, R out2 Indicates the actual resistance value of the outer ring resistance unit under current saturation conditions, K i , K o , Nsati, Nsato are the saturation effect parameters of the circuit model, K i is the fitting parameter of the inner circle resistance unit, K o is the fitting parameter of the outer circle resistance unit, Nsati is the voltage coefficient of the inner circle resistance unit, Nsato is the voltage coefficient of the outer circle resistance unit, Vsat represents the saturation voltage threshold, V represents an applied voltage greater than the saturation voltage threshold.

7. The simulation model construction method according to claim 5, wherein: The measuring of saturation current-voltage curves between different pairs of external ports under saturation current includes: Maintaining the ambient magnetic field intensity at zero and the measurement temperature unchanged, selecting two of the four external ports as measurement ports; applying a third voltage value sequence greater than the saturation voltage threshold to the measurement ports, and measuring a third current value sequence of the corresponding measurement ports; and obtaining a saturation current-voltage curve under saturation current based on the third voltage value sequence and the corresponding third current value sequence.

8. The simulation model construction method according to claim 1, wherein: Obtaining the sensitivity fitting parameters of the Hall magnetic sensor, including: Select two external ports on any diagonal line of the four external ports of the Hall effect magnetic sensor as input ports, and the other two external ports as measurement ports; At a first set temperature, measuring a first voltage-magnetic field curve of the output voltage and the ambient magnetic field strength corresponding to different input currents; Fitting first voltage-magnetic field curves corresponding to different input currents to extract initial sensitivity fitting parameters of the Hall magnetic sensor; Under the first set current, measuring the second voltage-magnetic field curve corresponding to the output voltage and the ambient magnetic field strength at different temperatures; Fitting the second voltage-magnetic field curve corresponding to different temperatures to extract the sensitivity temperature fitting parameters; The sensitivity fitting parameters of the Hall magnetic sensor are obtained according to the sensitivity temperature fitting parameters and the sensitivity initial fitting parameters.

9. The simulation model construction method according to claim 8, wherein: The temperature function relationship of the sensitivity fitting parameter is: Among them, S1 represents the first sensitivity fitting parameter of the Hall magnetic sensor, S2 represents the second sensitivity fitting parameter of the Hall magnetic sensor, and S 01 , S 02 represents the initial sensitivity fitting parameter, S 01 is the initial fitting parameter value of the first sensitivity, S 02 represents the second sensitivity initial fitting parameter value, stc1 and stc1 represent the sensitivity temperature fitting parameters, stc1 represents the sensitivity temperature first-order fitting parameter, and stc1 represents the sensitivity temperature second-order fitting parameter.

10. The simulation model construction method according to claim 1, wherein: The simulation model corresponding to the circuit model of the Hall magnetic sensor is: in, V h is the output voltage of the Hall magnetic sensor, I a is the input current, B is the ambient magnetic field strength, S1 and S2 are sensitivity fitting parameters, S1 is the first sensitivity fitting parameter of the Hall magnetic sensor, and S2 is the second sensitivity fitting parameter of the Hall magnetic sensor.

Images