CN221148783U

CN221148783U - Two-wire system hall sensor signal detection device based on comparator

Info

Publication number: CN221148783U
Application number: CN202323069607.9U
Authority: CN
Inventors: 陈泽坚; 陈敬晔; 陈发仁
Original assignee: Wuhu Etec Automotive Electronics Co ltd
Current assignee: Wuhu Etec Automotive Electronics Co ltd
Priority date: 2023-11-14
Filing date: 2023-11-14
Publication date: 2024-06-14
Anticipated expiration: 2033-11-14

Abstract

The utility model discloses a signal detection device of a two-wire Hall sensor based on a comparator, and belongs to the field of signal detection. The device comprises a two-wire Hall sensor, a Hall sensor power supply circuit, a comparator detection circuit, a threshold reference level circuit and a controller. The power line of the two-wire Hall sensor of the device is coupled with square wave signals, the power supply voltage of the Hall sensor is provided for the device through a Hall sensor power supply circuit, the power supply voltage of the Hall sensor is divided into proper threshold level through a threshold reference level circuit so as to be used by a comparator detection circuit, and the square wave signals coupled by the comparator detection circuit are converted into signals which can be identified by a controller. The device converts square wave signals on the power line of the two-wire Hall sensor into square wave signals which can be identified by the controller through the comparator capable of setting the threshold level, and has simple circuit structure and wide application.

Description

Two-wire system hall sensor signal detection device based on comparator

Technical Field

The utility model belongs to the field of signal detection, and particularly relates to a signal detection device of a two-wire Hall sensor based on a comparator.

Background

The market demand of automobile intellectualization, such as electric seat, electric back door etc. various comfort function popularity rate is higher and higher. The hall sensor is an important component, so that the position information of a seat, a back door and the like needs to be determined through the hall sensor to further improve the intelligent use experience so as to realize the functions of adjustment of a welcome seat and the like, and the two-wire hall sensor is a mainstream application in the field at present.

Hall sensors have only two wire harnesses (two-wire hall sensors): one path of sensor power supply and Hall PWM overlap signal line, one path of ground wire. The existing problem is that the Hall PWM signal is required to be separated when the two-wire Hall sensor is powered, and is converted into a signal which can be identified by a related controller.

The reference (CN 203772888U) discloses a device for acquiring the detection signal of a two-wire hall sensor, comprising: the signal sampling circuit is used for converting detection signals of the two-wire Hall sensor into voltage signals and is connected with the two-wire Hall sensor; the signal acquisition circuit is used for acquiring voltage signals; a signal acquisition and holding circuit for carrying out delay transmission on the voltage signal; and a comparator comparing the voltage signal with the voltage signal transmitted in a delayed manner to output a comparison signal recognizable by the controller. The device for collecting the detection signals of the two-wire Hall sensor only uses fewer general circuit components, not only can collect and process the detection signals of the two-wire Hall sensor in real time at a low side, but also can collect and process the detection signals of the two-wire Hall sensor in real time at a high side, and has the advantages of simple circuit, strong reliability, low cost and wide application range.

The above patent shows that for the use of the comparator, the selection of the threshold voltage is critical, and the above patent connects the in-phase end and the output end of the comparator to form feedback to realize signal conversion, so that the setting of the threshold voltage is directly avoided, but the normal operation of the comparator can not be realized while the setting of a simple threshold voltage is maintained, so that the signal of the two-wire hall sensor is converted into the signal recognizable by the controller. For this purpose, a two-wire hall sensor signal detection device based on a comparator is proposed.

Disclosure of utility model

The utility model aims to overcome the defects of the prior art, and provides a signal detection device of a two-wire system Hall sensor based on a comparator, so as to achieve the purpose of converting square wave signals coupled on a power wire of the two-wire system Hall sensor into signals recognizable by a controller through the comparator with a settable threshold value.

In order to achieve the above purpose, the technical scheme adopted by the utility model is as follows: the device comprises a two-wire system Hall sensor, a Hall sensor power supply providing circuit, a comparator detecting circuit, a threshold reference level circuit and a controller, wherein the sensor power supply output end of the Hall sensor power supply providing circuit is respectively connected with a power interface of the two-wire system Hall sensor and the positive input end of the comparator detecting circuit through a pull-up resistor R1; the power interface of the two-wire Hall sensor is connected with the positive input end of the comparator detection circuit; the two-wire Hall sensor comprises a triode Q1, wherein the collector of the triode Q1 is connected with a power interface of the two-wire Hall sensor through a resistor R2, and the emitter is grounded; the output end of the threshold reference level circuit is connected with the negative electrode input end of the comparator detection circuit; the output end of the comparator detection circuit is connected to the controller; the controller is also connected with the control end of the Hall sensor power supply circuit.

Further, the comparator detection circuit comprises a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C4 and a comparator U1, wherein the pull-up resistor R1 is decomposed into the resistor R3 and the resistor R4 which are connected in parallel, one end of the resistor R3 is connected with a sensor power supply V_HALL, and the other end of the resistor R3 is led out to serve as an anode input end of the comparator detection circuit; the first end of the capacitor C1 is connected with the resistor R3, and the second end of the capacitor C is grounded; the first end of the resistor R4 is connected with the sensor power supply V_HALL, and the second end of the resistor R4 is connected with the first end of the capacitor C1; the first end of the resistor R5 is connected with the second end of the resistor R4, and the second end of the resistor R5 is connected with the first end of the capacitor C2; the second end of the capacitor C2 is grounded; the non-inverting terminal of the comparator U1 is connected with the first terminal of the capacitor C2, and the inverting terminal is connected with the threshold reference level HALL_REF; the first end of the resistor R6 is connected with the controller power supply VCC, and the second end of the resistor R6 is connected with the output end of the comparator U1; the first end of the resistor R7 is connected with the second end of the resistor R6, and the second end is grounded; the first end of the capacitor C3 is connected with the first end of the resistor R7, the second end of the capacitor C3 is grounded, and the leading-out terminal of the first end of the capacitor C3 is used as the output end of the comparator detection circuit; one end of the capacitor C4 is connected with the sensor power supply V_HALL, and the other end of the capacitor C is grounded.

Further, the threshold reference level circuit comprises a resistor R8, a resistor R9 and a capacitor C5, wherein one end of the resistor R8 is connected with a sensor power supply V_HALL, and the other end of the resistor R8 is led out to serve as a threshold reference level output end HALL_REF; resistor R9 and capacitor C5 are connected in parallel, one end of the parallel connection is connected with threshold reference level output end HALL_REF, and the other end is grounded.

Further, the HALL sensor POWER supply circuit comprises an NPN type triode Q2, an NPN type triode Q4, a PNP type triode Q3, a resistor R10, a resistor R11, a resistor R12, a resistor R13, a resistor R14 and a capacitor C6, and a zener diode ZD1, wherein the controller controls an input end hall_power_en to be connected with a base electrode of the NPN type triode Q2 through the resistor R10, the base electrode of the NPN type triode Q2 is connected with an emitter electrode of the NPN type triode Q2 through the resistor R11, the emitter electrode of the NPN type triode Q2 is grounded, and a collector electrode of the NPN type triode Q2 is connected with a base electrode of the PNP type triode Q3 through the resistor R13; the base electrode of the PNP type triode Q3 is connected with the emitter electrode of the PNP type triode Q3 through a resistor R12, the emitter electrode of the PNP type triode Q3 is connected with the storage battery voltage VBAT_D, and the collector electrode of the PNP type triode Q3 is connected with the collector electrode of the NPN type triode Q4; the collector of the NPN triode Q4 is connected with the base electrode of the NPN triode Q4 through a resistor R14, the base electrode of the NPN triode Q4 is connected with the negative electrode of a voltage stabilizing diode ZD1, the positive electrode of the voltage stabilizing diode ZD1 is grounded, the emitter of the NPN triode Q4 is grounded through a capacitor C6, and a lead-out terminal between the emitter of the NPN triode Q4 and the capacitor C6 is used as a power supply output end V_HALL of the sensor.

Further, the pull-up resistor R1 is matched with the two-wire Hall sensor interface and is used for supplying power to the two-wire Hall sensor and sampling signals.

Further, the resistor R2 is configured to ensure that the two-wire hall sensor works normally and that the pull-up resistor R1 generates an effective voltage drop.

Further, the two-wire hall sensor is used for controlling the pull-up resistor R1 to generate different voltage drops through the internal triode Q1 when in operation; the Hall sensor power supply circuit is used for providing power supply voltage for the device; the threshold reference level circuit is used for dividing the power supply voltage of the Hall sensor into a proper threshold level for the comparator detection circuit to use; the comparator detection circuit is used for converting different voltage drops generated by the pull-up resistor R1 into signals which can be recognized by the controller.

The utility model has the technical effects that: (1) The square wave signal coupled on the power line of the two-wire Hall sensor is converted into a signal which can be identified by the controller; (2) The controller can control the opening and closing of the Hall sensor power supply circuit; (3) The threshold reference level of the appropriate comparator can be set by a simple threshold reference level circuit; and (4) the circuit structure is simple and the application is wide.

Drawings

FIG. 1 is a block diagram of a two-wire Hall sensor signal detection device based on a comparator according to the present utility model;

FIG. 2 is a diagram of a comparator detection circuit of a two-wire Hall sensor signal detection device based on a comparator of the present utility model;

FIG. 3 is a circuit diagram of a threshold reference level of a two-wire Hall sensor signal detection device based on a comparator of the present utility model;

fig. 4 is a schematic diagram of a hall sensor power supply circuit of a two-wire hall sensor signal-detecting apparatus according to the present utility model.

Marked in the figure as: R1-R14 are resistors; C1-C6 are capacitors; q1, Q2 and Q4 are NPN triodes; q2 is PNP triode; u1 is a comparator; ZD1 is a zener diode; V_HALL is the sensor POWER, HALL_REF is the threshold reference level, HALL_POWER_EN is the controller control input, VBAT_D is the battery voltage, POWER is the two-wire Hall sensor HALL square wave signal, VCC is the controller POWER supply.

Detailed Description

The following detailed description of the embodiments of the utility model, given by way of example only, is presented in the accompanying drawings to aid those skilled in the art in a more complete, accurate and thorough understanding of the inventive concepts and aspects of the utility model, and to facilitate their practice.

The device comprises a two-wire Hall sensor, a Hall sensor power supply providing circuit, a comparator detecting circuit, a threshold reference level circuit and a controller (the controller is an MCU in the embodiment), wherein the sensor power supply output end of the Hall sensor power supply providing circuit is respectively connected with a power interface of the two-wire Hall sensor and the positive input end of the comparator detecting circuit through a pull-up resistor R1; the power interface of the two-wire Hall sensor is connected with the positive input end of the comparator detection circuit; the two-wire Hall sensor comprises a triode Q1, wherein the collector of the triode Q1 is connected with a power interface of the two-wire Hall sensor through a resistor R2, and the emitter is grounded; the output end of the threshold reference level circuit is connected with the negative electrode input end of the comparator detection circuit; the output end of the comparator detection circuit is connected to the MCU; the MCU is also connected with the control end of the Hall sensor power supply circuit.

The two-wire Hall sensor is used for controlling the pull-up resistor R1 to generate different voltage drops through the internal triode Q1 when in operation; the Hall sensor power supply circuit is used for providing power supply voltage for the device; the threshold reference level circuit is used for dividing the power supply voltage of the Hall sensor into a proper threshold level for the comparator detection circuit to use; the comparator detection circuit is used for converting different voltage drops generated by the pull-up resistor R1 into signals which can be recognized by the MCU.

When the device works, the Hall sensor supply circuit supplies power to the whole device, so that devices such as the inside of the two-wire Hall sensor and the MCU are ensured to work within a required range. The triode Q1 mainly acts as a square wave, and when the two-wire Hall sensor works, the triode of the driving port is turned on or off, different voltage drops can be generated on the pull-up resistor R1 at the moment, and the comparator detection circuit unit converts the voltage drop on the pull-up resistor into a square wave signal which can be directly identified by the MCU. And the pull-up resistor R1 is used for supplying power to the two-wire Hall sensor through the power supply circuit of the Hall sensor on the one hand, and generating voltage drop according to the triode Q1 of the two-wire Hall sensor on the other hand so as to realize signal sampling. Therefore, the pull-up resistor needs to be matched with the interface of the two-wire Hall sensor, so that the port voltage generated after voltage drop on the resistor when the triode in the sensor is conducted can be ensured, and the normal operation of the two-wire sensor can be ensured; at the same time, the voltage drop across the resistor is also able to be converted normally to two levels of bits 0 and 1.

Meanwhile, a resistor R2 is connected in series with the collector electrode of the triode. The function of R2 is to ensure that when the triode is conducted, the power supply voltage of the port cannot be pulled down to 0V, so that the power supply voltage of the sensor cannot be too low to work, and R2 cannot be too small; meanwhile, R2 cannot be too large, otherwise, the voltage drop generated on R1 is too small, so that the voltage drop generated on R1 when the triode is conducted cannot be effectively identified. I.e. resistor R2 is used to ensure that the two-wire hall sensor is working properly and that the pull-up resistor R1 is generating an effective voltage drop for sampling.

The two-wire Hall sensor couples the frequency or protocol signal to a power supply wire through the voltage division of the resistors R1 and R2; meanwhile, the frequency signal coupled on the power line is converted into the frequency signal which can be directly identified by the MCU port through the detection circuit based on the comparator, and the circuit is simple in structure and wide in application.

Specifically, as shown in fig. 2, the comparator detection circuit includes a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C4, and a comparator U1, in this embodiment, the model of the comparator U1 is LM2903, where the pull-up resistor R1 is decomposed into a resistor R3 and a resistor R4 connected in parallel, one end of the resistor R3 is connected to the sensor POWER supply v_hall, and the other end of the resistor R3 is led out of the terminal as an input end of the positive electrode of the comparator detection circuit, and the input end inputs a HALL square wave signal POWER of the two-wire HALL sensor; the first end of the capacitor C1 is connected with the resistor R3, and the second end of the capacitor C is grounded; the first end of the resistor R4 is connected with the sensor power supply V_HALL, and the second end of the resistor R4 is connected with the first end of the capacitor C1; the first end of the resistor R5 is connected with the second end of the resistor R4, and the second end of the resistor R5 is connected with the first end of the capacitor C2; the second end of the capacitor C2 is grounded; the non-inverting terminal of the comparator U1 is connected with the first terminal of the capacitor C2, and the inverting terminal is connected with the threshold reference level HALL_REF; the first end of the resistor R6 is connected with the MCU power supply VCC, and the second end of the resistor R6 is connected with the output end of the comparator U1; the first end of the resistor R7 is connected with the second end of the resistor R6, and the second end is grounded; the first end of the capacitor C3 is connected with the first end of the resistor R7, the second end of the capacitor C3 is grounded, and the leading-out terminal of the first end of the capacitor C3 is used as the output end of the comparator detection circuit; one end of the capacitor C4 is connected with the sensor power supply V_HALL, and the other end of the capacitor C is grounded. The comparator U1 compares the signal input by the non-inverting terminal with the threshold level of the inverting terminal to output a square wave signal which can be identified by the MCU.

As shown in fig. 3, the threshold reference level circuit includes a resistor R8, a resistor R9, and a capacitor C5, where one end of the resistor R8 is connected to the sensor power supply v_hall, and the other end of the resistor R8 is led out to serve as a threshold reference level output terminal hall_ref; resistor R9 and capacitor C5 are connected in parallel, one end of the parallel connection is connected with threshold reference level output end HALL_REF, and the other end is grounded.

The reference level of the comparator is confirmed according to the specification of the Hall sensor and the voltage range of the high level and the low level of the square wave under the specified power supply voltage, the level can identify square wave signals within the error range, for example, the Hall sensor is in the high level range (UN > 6V) under the voltage of 7.5V, and the reference level of the comparator is set to 5V under the low level range (UN < 4V), and the voltage division of the power supply of the 7.5V sensor can be realized. Thus, the threshold level can be set by a simple voltage dividing circuit.

As shown in fig. 4, the HALL sensor POWER supply circuit includes an NPN type triode Q2, an NPN type triode Q4, a PNP type triode Q3, a resistor R10, a resistor R11, a resistor R12, a resistor R13, a resistor R14, a capacitor C6, a zener diode ZD1, in an embodiment, an NPN type triode selection BC846BW, a PNP type triode selection BC856BW, wherein an MCU control input terminal hall_power_en is connected to a base of the NPN type triode Q2 through the resistor R10, a base of the NPN type triode Q2 is connected to an emitter of the NPN type triode Q2 through the resistor R11, an emitter of the NPN type triode Q2 is grounded, and a collector of the NPN type triode Q2 is connected to a base of the PNP type triode Q3 through the resistor R13; the base electrode of the PNP type triode Q3 is connected with the emitter electrode of the PNP type triode Q3 through a resistor R12, the emitter electrode of the PNP type triode Q3 is connected with the storage battery voltage VBAT_D, and the collector electrode of the PNP type triode Q3 is connected with the collector electrode of the NPN type triode Q4; the collector of the NPN triode Q4 is connected with the base electrode of the NPN triode Q4 through a resistor R14, the base electrode of the NPN triode Q4 is connected with the negative electrode of a voltage stabilizing diode ZD1, the positive electrode of the voltage stabilizing diode ZD1 is grounded, the emitter of the NPN triode Q4 is grounded through a capacitor C6, and a lead-out terminal between the emitter of the NPN triode Q4 and the capacitor C6 is used as a power supply output end V_HALL of the sensor. The hall_power_en is an MCU control pin, and is used for controlling the on and off of the HALL sensor POWER supply, when the MCU controls the HALL sensor POWER supply v_hall to be on, the triode Q2 is turned on, the triode Q3 is turned on, the triode Q4 is turned on to output the HALL sensor POWER supply v_hall, that is, the HALL sensor POWER supply v_hall is stabilized and controlled after the battery POWER supply vbat_d is anti-reflective and TVS suppression processing, and the POWER supply can also be realized through a POWER supply chip.

The utility model is described above by way of example with reference to the accompanying drawings. It will be clear that the utility model is not limited to the embodiments described above. As long as various insubstantial improvements are made using the method concepts and technical solutions of the present utility model; or the utility model is not improved, and the conception and the technical scheme are directly applied to other occasions and are all within the protection scope of the utility model.

Claims

1. A two-wire system hall sensor signal detection device based on comparator, its characterized in that: the device comprises a two-wire Hall sensor, a Hall sensor power supply circuit, a comparator detection circuit, a threshold reference level circuit and a controller, wherein the sensor power supply output end of the Hall sensor power supply circuit is respectively connected with a power interface of the two-wire Hall sensor and the positive input end of the comparator detection circuit through a pull-up resistor (R1); the power interface of the two-wire Hall sensor is connected with the positive input end of the comparator detection circuit; the two-wire Hall sensor comprises a triode (Q1), wherein a collector electrode of the triode (Q1) is connected with a power interface of the two-wire Hall sensor through a resistor (R2), and an emitter electrode is grounded; the output end of the threshold reference level circuit is connected with the negative electrode input end of the comparator detection circuit; the output end of the comparator detection circuit is connected to the controller; the controller is also connected with the control end of the Hall sensor power supply circuit.

2. The comparator-based two-wire hall sensor signal-detecting apparatus of claim 1, wherein: the comparator detection circuit comprises a resistor (R3), a resistor (R4), a resistor (R5), a resistor (R6), a resistor (R7), a capacitor (C1), a capacitor (C2), a capacitor (C3), a capacitor (C4) and a comparator (U1), wherein the pull-up resistor (R1) is decomposed into the resistor (R3) and the resistor (R4) which are connected in parallel, one end of the resistor (R3) is connected with a sensor power supply (V_HALL), and the other end of the resistor is led out of a terminal to serve as an anode input end of the comparator detection circuit; the first end of the capacitor (C1) is connected with the resistor (R3), and the second end of the capacitor is grounded; the first end of the resistor (R4) is connected with the sensor power supply (V_HALL), and the second end of the resistor is connected with the first end of the capacitor (C1); the first end of the resistor (R5) is connected with the second end of the resistor (R4), and the second end of the resistor is connected with the first end of the capacitor (C2); the second end of the capacitor (C2) is grounded; the non-inverting terminal of the comparator (U1) is connected with the first terminal of the capacitor (C2), and the inverting terminal is connected with the threshold reference level (HALL_REF); the first end of the resistor (R6) is connected with the power supply (VCC) of the controller, and the second end of the resistor is connected with the output end of the comparator (U1); the first end of the resistor (R7) is connected with the second end of the resistor (R6), and the second end is grounded; the first end of the capacitor (C3) is connected with the first end of the resistor (R7), the second end of the capacitor is grounded, and the first end leading-out terminal of the capacitor (C3) is used as the output end of the comparator detection circuit; one end of the capacitor (C4) is connected with the sensor power supply (V_HALL), and the other end of the capacitor is grounded.

3. The comparator-based two-wire hall sensor signal-detecting apparatus of claim 1, wherein: the threshold reference level circuit comprises a resistor (R8), a resistor (R9) and a capacitor (C5), wherein one end of the resistor (R8) is connected with a sensor power supply (V_HALL), and the other end of the resistor is led out to serve as a threshold reference level output end (HALL_REF); the resistor (R9) and the capacitor (C5) are connected in parallel, one end of the parallel connection is connected with the threshold reference level output end (HALL_REF), and the other end of the parallel connection is grounded.

4. The comparator-based two-wire hall sensor signal-detecting apparatus of claim 1, wherein: the Hall sensor POWER supply circuit comprises an NPN type triode (Q2), an NPN type triode (Q4), a PNP type triode (Q3), a resistor (R10), a resistor (R11), a resistor (R12), a resistor (R13), a resistor (R14) and a capacitor (C6), and a voltage-stabilizing diode (ZD 1), wherein a control input end (HALL_POWER_EN) of the controller is connected with a base electrode of the NPN type triode (Q2) through the resistor (R10), the base electrode of the NPN type triode (Q2) is connected with an emitter electrode of the NPN type triode (Q2) through the resistor (R11), the emitter electrode of the NPN type triode (Q2) is grounded, and a collector electrode of the NPN type triode (Q2) is connected with a base electrode of the PNP type triode (Q3) through the resistor (R13); the base electrode of the PNP type triode (Q3) is connected with the emitter electrode of the PNP type triode (Q3) through a resistor (R12), the emitter electrode of the PNP type triode (Q3) is connected with a storage battery voltage (VBAT_D), and the collector electrode of the PNP type triode (Q3) is connected with the collector electrode of the NPN type triode (Q4); the collector of the NPN triode (Q4) is connected with the base electrode of the NPN triode (Q4) through a resistor (R14), the base electrode of the NPN triode (Q4) is connected with the cathode of a voltage stabilizing diode (ZD 1), the anode of the voltage stabilizing diode (ZD 1) is grounded, the emitter of the NPN triode (Q4) is grounded through a capacitor (C6), and a lead-out terminal between the emitter of the NPN triode (Q4) and the capacitor (C6) is used as a sensor power supply output end (V_HALL).

5. The comparator-based two-wire hall sensor signal-detecting apparatus of claim 1, wherein: the pull-up resistor (R1) is matched with the two-wire Hall sensor interface and is used for supplying power to the two-wire Hall sensor and sampling signals.

6. A comparator-based two-wire hall sensor signal-detecting apparatus according to claim 1 or 5, wherein: the resistor (R2) is used for ensuring that the two-wire Hall sensor works normally and ensuring that the pull-up resistor (R1) generates effective voltage drop.

7. The comparator-based two-wire hall sensor signal-detecting apparatus of claim 1, wherein: the two-wire Hall sensor is used for controlling the pull-up resistor (R1) to generate different voltage drops through an internal triode (Q1) during operation; the Hall sensor power supply circuit is used for providing power supply voltage for the device; the threshold reference level circuit is used for dividing the power supply voltage of the Hall sensor into a proper threshold level for the comparator detection circuit to use; the comparator detection circuit is used for converting different voltage drops generated by the pull-up resistor (R1) into signals which can be recognized by the controller.