Dual wire hall sensor signal conversion circuitry

Abstract

The double-line Hall sensor signal conversion circuit system comprises a Hall sensor, a comparator, a reference voltage dividing resistor, a feedback network, a signal filtering unit, and a power supply processing unit. The comparator is used for comparing a signal from the Hall sensor with a reference voltage and outputting a conversion signal. The reference voltage dividing resistor is used for providing a determined reference voltage to one input end of the comparator. The feedback network is used for feeding back a part of the comparator output to the comparator input to introduce hysteresis. The signal filtering unit is used for noise suppression of the input signal of the Hall sensor. The power supply processing unit is used for providing voltage reduction or current limiting, filtering, and transient protection for the Hall sensor and the comparator. The output end of the comparator is electrically connected with a back-end microprocessor or control unit through an interface circuit to provide a stable logic level output. The comparator, the reference voltage dividing network, the feedback network, the signal filtering unit, and the power supply processing unit work together to stably convert the on or high resistance state of the double-line Hall sensor into a level signal recognizable by the back end.

Description

Technical Field

[0001] This utility model relates to a dual-wire Hall sensor signal conversion circuit system, belonging to the field of automation. Background Technology

[0002] Dual-wire Hall effect sensors are widely used in automotive electronics (such as position detection and speed detection), industrial control, and other magnetic field detection applications due to their simple structure and high reliability. Dual-wire Hall effect sensors typically only provide two-state outputs: on / high impedance. However, their outputs are passive signals with open circuit or high impedance. When directly connected to a microprocessor or vehicle control module, they often lead to misjudgments or false triggers due to a lack of anti-interference capability, unclear threshold, slow edge response, and susceptibility to jitter.

[0003] While some simple pull-up resistors or single-stage filtering solutions can work in ideal environments, they still suffer from insufficient anti-interference capabilities, signal jitter, and unstable response under complex automotive electromagnetic environments (such as switching noise, induced pulses, and transient interference), affecting the reliability and safety of the entire vehicle system. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings and deficiencies of the existing technology and to provide a dual-wire Hall sensor signal conversion circuit system.

[0005] A dual-wire Hall sensor signal conversion circuit system includes a Hall sensor, a comparator for comparing a signal from the Hall sensor with a reference voltage and outputting a converted signal; a reference voltage divider resistor for providing a defined reference voltage to one input of the comparator; a feedback network for feeding back a portion of the comparator output to the comparator input to introduce hysteresis; a signal filtering unit for noise suppression of the input signal from the Hall sensor; and a power supply processing unit for providing step-down or current-limiting, filtering, and transient protection for the Hall sensor and comparator. The output of the comparator is electrically connected to a back-end microprocessor or control unit via an interface circuit to provide a stable logic level output. The comparator, reference voltage divider network, feedback network, signal filtering unit, and power supply processing unit work together to stably convert the on or high-impedance state of the dual-wire Hall sensor into a back-end recognizable logic level signal.

[0006] This technical solution utilizes a voltage divider between two resistors to create a stable reference voltage, enabling the comparator to determine the input signal within a fixed threshold. This avoids threshold drift caused by power supply fluctuations or environmental interference, thus improving the stability and consistency of level determination. The comparator forms a hysteresis window through a feedback resistor, resulting in a threshold difference between the upper and lower thresholds during signal switching. This effectively prevents frequent transitions caused by noise, signal jitter, or slow edges, improving anti-interference capability and signal edge clarity, ensuring stable output signal. The circuit accurately identifies the sensor's high impedance and conduction states, converting them into stable low and high level outputs, thus ensuring compatibility with standard digital circuit interfaces. Its output signal is clean and responsive, effectively suppressing interference and ensuring that subsequent control units can reliably obtain the Hall sensor status, providing stable and accurate logic input for the entire system's functionality.

[0007] Preferably, the reference voltage divider network includes at least two voltage divider resistors for forming the reference voltage node at one input terminal of the comparator.

[0008] This technical solution uses a voltage divider between two resistors to create a stable reference voltage, enabling the comparator to determine the input signal within a fixed threshold. This avoids threshold drift caused by power supply fluctuations or environmental interference, thus improving the stability and consistency of level determination. Connecting a resistor in series and a capacitor in parallel at the Hall sensor signal terminal forms an RC filter network, which suppresses high-frequency noise and transient interference pulses, preventing false triggering. Simultaneously, the filter capacitor improves the stability of the comparator input, allowing the system to operate reliably in complex electromagnetic environments.

[0009] Furthermore, the comparator is an open-collector output comparator, and the comparator output is pulled up to the system level through an external pull-up resistor.

[0010] This technical solution employs an open-collector output comparator, which allows the output to provide only on / off capability without directly driving the level, thus providing good level compatibility and flexibility. By setting an external pull-up resistor at the output, the comparator's output signal can be stably pulled to the logic level required by the system (e.g., 5V or 3.3V), achieving compatibility with back-end microprocessors or vehicle ECUs of different voltage levels.

[0011] Furthermore, a current-limiting resistor is connected in series between the comparator input terminal and the Hall signal node to limit the transient current flowing into the comparator input terminal and together with the parallel signal capacitor, form the filtering characteristics of the signal terminal.

[0012] This technical solution effectively limits the flow of external interference pulses or transient surge currents into the comparator by connecting a current-limiting resistor in series between the comparator input and the Hall signal node, thus preventing damage or malfunction of the comparator chip. The current-limiting resistor and the parallel signal capacitor together form an RC filter network, which can perform low-pass filtering on the input signal, suppress high-frequency noise and spike interference, and improve the purity of the input signal. This design not only improves the circuit's anti-interference capability and reliability but also enhances the comparator's judgment accuracy, ensuring the signal stability of the dual-wire Hall sensor in complex electromagnetic environments.

[0013] Preferably, the feedback network includes at least one pair of feedback resistors, which feed back a portion of the signal output by the comparator to the non-inverting or inverting input of the comparator, thereby creating a hysteresis characteristic with upper and lower threshold separation within the comparator.

[0014] This technical solution uses a feedback resistor to feed a portion of the voltage at the comparator's output back to the input, allowing the comparator to have different trigger thresholds when switching between high and low levels, thus creating a hysteresis effect. The hysteresis characteristic effectively prevents frequent jittering caused by slow input signal edges or interference noise, ensuring a stable and reliable output signal. This structure is simple and easy to implement; the hysteresis magnitude can be set simply by adjusting the ratio of the feedback resistor to the voltage divider resistor, adapting to the anti-interference requirements of different application scenarios.

[0015] Preferably, the signal filtering unit includes a signal filtering capacitor connected in parallel with the Hall sensor and a current limiting or pull-up resistor connected in series with the Hall sensor and the parallel node of the signal filtering capacitor.

[0016] This technical solution effectively low-pass filters the input signal by connecting a signal filtering capacitor in parallel to the Hall signal node, suppressing high-frequency noise and transient spike interference. The current-limiting or pull-up resistor connected in series with this node not only acts as a signal bias or pull-up resistor in the circuit, but also forms an RC filter network together with the filtering capacitor, thereby improving the smoothness and stability of the input signal. This design enhances the circuit's anti-interference performance while ensuring signal integrity, enabling the dual-wire Hall sensor to output stable logic signals even in complex electromagnetic environments.

[0017] Preferably, the power processing unit includes a step-down or current-limiting device, a power filter capacitor, and a protection diode for limiting transient or overvoltage.

[0018] This technical solution uses step-down or current-limiting devices in the power processing unit to adjust the input power supply to the safe level required by the circuit, while avoiding the impact of overcurrent or overvoltage caused by power supply sudden changes on the subsequent circuits. When used in conjunction with power supply filter capacitors, it can smooth and filter power supply ripple and noise, improving the stability of the circuit power supply.

[0019] The beneficial effects of this invention are as follows: By using two resistors to divide the voltage and form a stable reference voltage, the comparator can determine the input signal within a fixed threshold, avoiding threshold drift caused by power supply fluctuations or environmental interference, thereby improving the stability and consistency of level determination. The comparator forms a hysteresis window through a feedback resistor, resulting in a threshold difference between the upper and lower thresholds for signal switching. This effectively avoids frequent jumps caused by noise, signal jitter, or slow edges, improving anti-interference capability and signal edge clarity, and ensuring stable output signal. This circuit can accurately identify the high impedance and conduction state of the sensor and convert them into stable low and high level outputs, thus ensuring compatibility with standard digital circuit interfaces. Its output signal is clean and has a rapid response, effectively suppressing interference and ensuring that subsequent control units can reliably obtain the Hall sensor status, providing stable and accurate logic input for the entire system's functionality. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, obtaining other drawings based on these drawings without creative effort still falls within the scope of this utility model.

[0021] Figure 1 This is the circuit diagram of the power supply of this utility model; Figure 2 This is a complete circuit diagram of the conversion circuit of this utility model; In the diagram, R5 and R11 are negative reference voltage divider resistors; R1 and R6 are feedback hysteresis resistors; R2 and R9 are Hall sensor power supply and signal pull-up resistors; R4 and R8 are comparator current limiting resistors; C1 and C2 are power supply filters; R3 and R7 are 5V pull-up resistors; C3 and C4 are signal filters; U1 is a comparator; Q1 is a Hall sensor power supply step-down resistor; C5 and C6 are power supply filters; R10 is a current limiter; and DZ1 is the Hall power supply emitter output voltage control. Detailed Implementation

[0022] To make the objectives, technical solutions and advantages of this utility model clearer, the utility model will be described in further detail below with reference to the accompanying drawings.

[0023] It should be noted that all uses of "first" and "second" in the embodiments of this utility model are for the purpose of distinguishing two entities or parameters with the same name but different names. It is clear that "first" and "second" are only for the convenience of expression and should not be construed as limiting the embodiments of this utility model. Subsequent embodiments will not explain this in detail.

[0024] The directional and positional terms used in this utility model, such as "up," "down," "front," "back," "left," "right," "inner," "outer," "top," "bottom," and "side," are merely for reference to the accompanying drawings. Therefore, the directional and positional terms used are for the purpose of explaining and understanding this utility model, and not for limiting the scope of protection of this utility model.

[0025] like Figure 1-2 The diagram illustrates an embodiment of the dual-wire Hall sensor signal conversion circuit system of this invention. It includes a Hall sensor, a comparator for comparing a signal from the Hall sensor with a reference voltage and outputting a converted signal, a reference voltage divider resistor for providing a defined reference voltage to one input of the comparator, a feedback network for feeding a portion of the comparator output back to the comparator input to introduce hysteresis, a signal filtering unit for noise suppression of the input signal from the Hall sensor, and a power supply unit for providing voltage reduction or current limiting, filtering, and transient protection to the Hall sensor and comparator. The output of the comparator is electrically connected to a back-end microprocessor or control unit via an interface circuit to provide a stable logic level output. The comparator, reference voltage divider network, feedback network, signal filtering unit, and power supply unit work together to stably convert the on or high-impedance state of the dual-wire Hall sensor into a back-end recognizable level signal.

[0026] This technical solution utilizes a voltage divider between two resistors to create a stable reference voltage, enabling the comparator to determine the input signal within a fixed threshold. This avoids threshold drift caused by power supply fluctuations or environmental interference, thus improving the stability and consistency of level determination. The comparator forms a hysteresis window through a feedback resistor, resulting in a threshold difference between the upper and lower thresholds during signal switching. This effectively prevents frequent transitions caused by noise, signal jitter, or slow edges, improving anti-interference capability and signal edge clarity, ensuring stable output signal. The circuit accurately identifies the sensor's high impedance and conduction states, converting them into stable low and high level outputs, thus ensuring compatibility with standard digital circuit interfaces. Its output signal is clean and responsive, effectively suppressing interference and ensuring that subsequent control units can reliably obtain the Hall sensor status, providing stable and accurate logic input for the entire system's functionality.

[0027] The reference voltage divider network includes at least two voltage divider resistors for forming the reference voltage node at one input of the comparator.

[0028] This technical solution uses a voltage divider between two resistors to create a stable reference voltage, enabling the comparator to determine the input signal within a fixed threshold. This avoids threshold drift caused by power supply fluctuations or environmental interference, thus improving the stability and consistency of level determination. Connecting a resistor in series and a capacitor in parallel at the Hall sensor signal terminal forms an RC filter network, which suppresses high-frequency noise and transient interference pulses, preventing false triggering. Simultaneously, the filter capacitor improves the stability of the comparator input, allowing the system to operate reliably in complex electromagnetic environments.

[0029] The comparator is an open-collector output type comparator, and the comparator output is pulled up to the system level through an external pull-up resistor.

[0030] This technical solution employs an open-collector output comparator, which allows the output to provide only on / off capability without directly driving the level, thus providing good level compatibility and flexibility. By setting an external pull-up resistor at the output, the comparator's output signal can be stably pulled to the logic level required by the system (e.g., 5V or 3.3V), achieving compatibility with back-end microprocessors or vehicle ECUs of different voltage levels.

[0031] A current-limiting resistor is connected in series between the comparator input terminal and the Hall signal node to limit the transient current flowing into the comparator input terminal and together with the parallel signal capacitor, form the filtering characteristics of the signal terminal.

[0032] This technical solution effectively limits the flow of external interference pulses or transient surge currents into the comparator by connecting a current-limiting resistor in series between the comparator input and the Hall signal node, thus preventing damage or malfunction of the comparator chip. The current-limiting resistor and the parallel signal capacitor together form an RC filter network, which can perform low-pass filtering on the input signal, suppress high-frequency noise and spike interference, and improve the purity of the input signal. This design not only improves the circuit's anti-interference capability and reliability but also enhances the comparator's judgment accuracy, ensuring the signal stability of the dual-wire Hall sensor in complex electromagnetic environments.

[0033] The feedback network includes at least one pair of feedback resistors, which feed back a portion of the signal output by the comparator to the non-inverting or inverting input of the comparator, thereby creating a hysteresis characteristic with upper and lower threshold separation within the comparator.

[0034] This technical solution uses a feedback resistor to feed a portion of the voltage at the comparator's output back to the input, allowing the comparator to have different trigger thresholds when switching between high and low levels, thus creating a hysteresis effect. The hysteresis characteristic effectively prevents frequent jittering caused by slow input signal edges or interference noise, ensuring a stable and reliable output signal. This structure is simple and easy to implement; the hysteresis magnitude can be set simply by adjusting the ratio of the feedback resistor to the voltage divider resistor, adapting to the anti-interference requirements of different application scenarios.

[0035] The signal filtering unit includes a signal filtering capacitor connected in parallel with the Hall sensor and a current limiting or pull-up resistor connected in series with the Hall sensor and the parallel node of the signal filtering capacitor.

[0036] This technical solution effectively low-pass filters the input signal by connecting a signal filtering capacitor in parallel to the Hall signal node, suppressing high-frequency noise and transient spike interference. The current-limiting or pull-up resistor connected in series with this node not only acts as a signal bias or pull-up resistor in the circuit, but also forms an RC filter network together with the filtering capacitor, thereby improving the smoothness and stability of the input signal. This design enhances the circuit's anti-interference performance while ensuring signal integrity, enabling the dual-wire Hall sensor to output stable logic signals even in complex electromagnetic environments.

[0037] The power processing unit includes a step-down or current-limiting device, a power filter capacitor, and a protection diode for limiting transient or overvoltage.

[0038] This technical solution uses step-down or current-limiting devices in the power processing unit to adjust the input power supply to the safe level required by the circuit, while avoiding the impact of overcurrent or overvoltage caused by power supply sudden changes on the subsequent circuits. When used in conjunction with power supply filter capacitors, it can smooth and filter power supply ripple and noise, improving the stability of the circuit power supply.

[0039] The comparator is preferably an LM2903A or a functionally equivalent open-collector output comparator. The resistance ratio of R1 and R6 is used in conjunction with the resistance ratio of R5 and R11 to determine the upper and lower thresholds of the comparator. The RC time constants of C3, C4 and R4, R8 are used to suppress short-time interference pulses while meeting the system response speed requirements.

[0040] The non-inverting and inverting inputs of comparator U1 are connected to the reference voltage node formed by the reference voltage divider resistors R5 and R11, and the signal node, which is the output of the Hall sensor processed by R2 / R4 and the parallel filter capacitor C3. The comparator output is pulled up to 5V through the pull-up resistor R3 and fed back to the reference node through R1 to create hysteresis. The Hall power supply is defined by Q1 and the current-limiting resistor R10. Power supply filter capacitors C1 and C2 are connected in parallel next to the power supply to suppress transients. DZ1 is a transient suppression diode used to limit overvoltage surges on the power supply path.

[0041] Building upon the above, a common-mode inductor is added, a larger capacity signal filter is used, the feedback resistor value is reduced to increase the hysteresis amplitude, and a buffer / drive stage is added at the comparator output to improve the driving capability and disturbance rejection capability for downstream loads. For the Hall effect power supply side, an LDO or buck module with overcurrent and thermal protection is preferred, and automotive-grade components are used when selecting the TVS (DZ1) to meet the system's transient pulse absorption requirements.

[0042] The above-disclosed embodiments are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent variations made in accordance with the claims of the present utility model shall still fall within the scope of the present utility model.

[0043] Although the present invention has been described with reference to several specific embodiments, it should be understood that the present invention is not limited to the specific embodiments disclosed. The present invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A dual-wire Hall sensor signal conversion circuit system, characterized in that: It includes a Hall sensor, a comparator for comparing a signal from the Hall sensor with a reference voltage and outputting a conversion signal; and a reference voltage divider resistor for providing a defined reference voltage to one input of the comparator. Feedback network is used to feed a portion of the comparator output back to the comparator input to introduce hysteresis; The signal filtering unit is used to suppress noise in the input signal of the Hall sensor; the power supply processing unit is used to provide step-down or current limiting, filtering and transient protection for the Hall sensor and comparator; the output of the comparator is electrically connected to the back-end microprocessor or control unit via an interface circuit to provide a stable logic level output; the comparator, reference voltage divider network, feedback network, signal filtering unit and power supply processing unit work together to stably convert the on or high-impedance state of the dual-wire Hall sensor into a level signal that can be recognized by the back-end.

2. The dual-wire Hall sensor signal conversion circuit system as described in claim 1, characterized in that: The reference voltage divider network includes at least two voltage divider resistors for forming the reference voltage node at one input of the comparator.

3. The dual-wire Hall sensor signal conversion circuit system as described in claim 2, characterized in that: The comparator is an open-collector output type comparator, and the comparator output is pulled up to the system level through an external pull-up resistor.

4. The dual-wire Hall sensor signal conversion circuit system as described in claim 2 or 3, characterized in that: A current-limiting resistor is connected in series between the comparator input terminal and the Hall signal node to limit the transient current flowing into the comparator input terminal and together with the parallel signal capacitor, form the filtering characteristics of the signal terminal.

5. The dual-wire Hall sensor signal conversion circuit system as described in claim 1, characterized in that: The feedback network includes at least one pair of feedback resistors, which feed back a portion of the signal output by the comparator to the non-inverting or inverting input of the comparator, thereby creating a hysteresis characteristic with upper and lower threshold separation within the comparator.

6. The dual-wire Hall sensor signal conversion circuit system as described in claim 1, characterized in that: The signal filtering unit includes a signal filtering capacitor connected in parallel with the Hall sensor and a current limiting or pull-up resistor connected in series with the Hall sensor and the parallel node of the signal filtering capacitor.

7. The dual-wire Hall sensor signal conversion circuit system as described in claim 1, characterized in that: The power processing unit includes a step-down or current-limiting device, a power filter capacitor, and a protection diode for limiting transient or overvoltage.

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