Brushless motor driver Hall sensor interface protection circuit

Abstract

The utility model provides a brushless motor driver Hall sensor interface protection circuit, and relates to the technical field of electronic circuits. Comprising a first sub-circuit, a second sub-circuit and a third sub-circuit. The first sub-circuit comprises a first filtering unit and a first Hall signal anti-backflow unit which are connected in sequence, and the first filtering unit is connected to a first Hall signal output end; the second sub-circuit comprises a second filtering unit and a second Hall signal anti-backflow unit which are connected in sequence, and the second filtering unit is connected to a second Hall signal output end; the third sub-circuit comprises a third filtering unit and a third Hall signal anti-backflow unit which are connected in sequence, and the third filtering unit is connected to a third Hall signal output end; and the first Hall signal anti-backflow unit, the second Hall signal anti-backflow unit and the third Hall signal anti-backflow unit are respectively connected to the Hall sensor interface. According to the invention, high voltage can be prevented from flowing backwards to the three output ends of the Hall signal, and the circuit and the brushless motor driver are prevented from being damaged.

Description

Technical Field

[0001] This application relates to the field of electronic circuit technology, and in particular to a protection circuit for a Hall sensor interface of a brushless motor driver. Background Technology

[0002] A brushless motor mainly consists of a motor body assembly, including a stator core and a rotor core. Hall effect sensors are commonly used components on the stator core to sense the rotor position. The Hall effect sensor circuit in the brushless motor driver connects to the motor's Hall effect angle sensor and is a crucial circuit for motor operation. In actual production, assembly issues occasionally lead to short circuits between the motor's three-phase lines and the Hall effect sensor lines, burning out the brushless motor driver and causing significant losses.

[0003] Therefore, designing a protection circuit for the Hall sensor interface of a brushless motor driver that can prevent short circuits is one of the urgent problems to be solved. Utility Model Content

[0004] This application provides a protection circuit for the Hall sensor interface of a brushless motor driver, which at least solves the above-mentioned technical problems existing in the prior art.

[0005] According to a first aspect of this application, a brushless motor driver Hall sensor interface protection circuit is provided, including a first sub-circuit, a second sub-circuit and a third sub-circuit.

[0006] The first sub-circuit includes a first filter unit and a first Hall signal backflow prevention unit connected in sequence, with the first filter unit connected to the first output terminal of the Hall signal; the second sub-circuit includes a second filter unit and a second Hall signal backflow prevention unit connected in sequence, with the second filter unit connected to the second output terminal of the Hall signal; the third sub-circuit includes a third filter unit and a third Hall signal backflow prevention unit connected in sequence, with the third filter unit connected to the third output terminal of the Hall signal; the first Hall signal backflow prevention unit, the second Hall signal backflow prevention unit, and the third Hall signal backflow prevention unit are respectively connected to the Hall sensor interface.

[0007] In some embodiments of the first aspect of this application, the first filtering unit, the second filtering unit, and the third filtering unit are RC filtering units.

[0008] In some embodiments of the first aspect of this application, the first filtering unit includes a first filtering capacitor and a second filtering resistor. The first terminal of the first filtering capacitor is grounded, and the second terminal of the first filtering capacitor and the first terminal of the second filtering resistor are connected together to the first output terminal of the Hall signal.

[0009] In some embodiments of the first aspect of this application, the first Hall signal backflow prevention unit includes a second diode, the positive terminal of the second diode is connected to the second end of the second filter resistor, and the negative terminal of the second diode is connected to the Hall sensor interface.

[0010] In some embodiments of the first aspect of this application, the second filtering unit includes a second filtering capacitor and a fourth filtering resistor. The first terminal of the second filtering capacitor is grounded, and the second terminal of the second filtering capacitor and the first terminal of the fourth filtering resistor are connected together to the second output terminal of the Hall signal.

[0011] In some embodiments of the first aspect of this application, the second Hall signal backflow prevention unit includes a third diode, the positive terminal of which is connected to the second end of a fourth filter resistor, and the negative terminal of which is connected to the Hall sensor interface.

[0012] In some embodiments of the first aspect of this application, the third filtering unit includes a third filtering capacitor and a sixth filtering resistor. The first terminal of the third filtering capacitor is grounded, and the second terminal of the third filtering capacitor and the first terminal of the sixth filtering resistor are connected together to the third output terminal of the Hall signal.

[0013] In some embodiments of the first aspect of this application, the third Hall signal anti-backflow unit includes a fourth diode, the positive terminal of the fourth diode is connected to the second terminal of the sixth filter resistor, and the negative terminal of the fourth diode is connected to the Hall sensor interface.

[0014] In some embodiments of the first aspect of this application, pull-up resistors are respectively provided between the first filtering unit and the first Hall signal anti-backflow unit, between the second filtering unit and the second Hall signal anti-backflow unit, and between the third filtering unit and the third Hall signal anti-backflow unit.

[0015] In some embodiments of the first aspect of this application, a Hall sensor power supply anti-backflow diode is further included, wherein the positive terminal of the Hall sensor power supply anti-backflow diode is connected to a high level and the negative terminal of the Hall sensor power supply anti-backflow diode is connected to the Hall sensor interface.

[0016] Compared with the prior art, this application has the following advantages:

[0017] This application sets corresponding filtering units and Hall signal backflow prevention units at the three output terminals of the Hall signal. The Hall signal backflow prevention unit has unidirectional conductivity, which can prevent high voltage backflow to the three output terminals of the Hall signal and avoid damage to the circuit and its brushless motor driver.

[0018] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this application, nor is it intended to limit the scope of this application. Other features of this application will become readily apparent from the following description. Attached Figure Description

[0019] The above and other objects, features, and advantages of exemplary embodiments of this application will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings. Several embodiments of this application are illustrated in the drawings by way of example and not limitation, in which:

[0020] In the accompanying drawings, the same or corresponding reference numerals indicate the same or corresponding parts.

[0021] Figure 1 The circuit block diagram of this application is shown.

[0022] Figure 2 The specific circuit diagram of this application is shown. Detailed Implementation

[0023] To make the objectives, features, and advantages of this application more apparent and understandable, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0024] This embodiment provides a protection circuit for the Hall sensor interface of a brushless motor driver, including a first sub-circuit, a second sub-circuit, and a third sub-circuit.

[0025] Please follow Figure 1 The first sub-circuit includes a first filter unit and a first Hall signal anti-backflow unit connected in sequence. The first filter unit is connected to the first output terminal HALL_A of the Hall signal, and the first Hall signal anti-backflow unit is connected to the Hall sensor interface.

[0026] For details, please refer to Figure 2 The first filtering unit is an RC filtering unit, including a first filtering capacitor C1 and a second filtering resistor R2. The first terminal of the first filtering capacitor C1 is grounded, and the second terminal of the first filtering capacitor C1 and the first terminal of the second filtering resistor R2 are connected to the first output terminal HALL_A of the Hall signal. Under the combined action of the first filtering capacitor C1 and the second filtering resistor R2, the Hall sensor signal is filtered to remove high-frequency interference signals.

[0027] The first Hall signal backflow prevention unit includes a second diode D2. The positive terminal of the second diode D2 is connected to the second end of the second filter resistor R2, and the negative terminal of the second diode D2 is connected to the Hall sensor interface J1. Due to the unidirectional conductivity of the second diode D2, high voltage backflow to the output terminal of the signal filter can be prevented, thus avoiding damage to the circuit and its brushless motor driver.

[0028] The Hall sensor interface J1 is preferably of model BLDC-HALL, and has 5 wires, including the positive terminal HVCC of the Hall sensor power supply, the Hall sensor input signal terminals HA, HB, and HC, and the negative terminal GND of the Hall sensor power supply. The negative terminal of the second diode D2 is connected to the Hall sensor input signal terminal HA of the Hall sensor interface J1.

[0029] Similarly, the second sub-circuit includes a second filter unit and a second Hall signal backflow prevention unit connected in sequence, with the second filter unit connected to the second output terminal HALL_B of the Hall signal. The third sub-circuit includes a third filter unit and a third Hall signal backflow prevention unit connected in sequence, with the third filter unit connected to the third output terminal HALL_C of the Hall signal. The second and third Hall signal backflow prevention units are respectively connected to the Hall sensor interface.

[0030] Please refer to Figure 2 The second and third filtering units are also RC filtering units.

[0031] The second filtering unit includes a second filtering capacitor C2 and a fourth filtering resistor R4. The first terminal of the second filtering capacitor C2 is grounded, and the second terminal of the second filtering capacitor C2 and the first terminal of the fourth filtering resistor R4 are connected to the second output terminal HALL_B of the Hall signal. Under the combined action of the second filtering capacitor C2 and the fourth filtering resistor R4, the Hall sensor signal is filtered to remove high-frequency interference signals.

[0032] The second Hall signal backflow prevention unit includes a third diode D3. The positive terminal of the third diode D3 is connected to the second end of the fourth filter resistor R4, and the negative terminal of the third diode D3 is connected to the Hall sensor interface J1, specifically the Hall sensor input signal terminal HB of the Hall sensor interface J1. Due to the unidirectional conductivity of the third diode D3, high voltage backflow to the output terminal of the signal filter can be prevented, thus avoiding damage to the circuit and its brushless motor driver.

[0033] The third filtering unit includes a third filtering capacitor C3 and a sixth filtering resistor R6. The first terminal of the third filtering capacitor C3 is grounded, and the second terminal of the third filtering capacitor C3 and the first terminal of the sixth filtering resistor R6 are connected to the third output terminal HALL_C of the Hall signal. Under the combined action of the third filtering capacitor C3 and the sixth filtering resistor R6, the Hall sensor signal is filtered to remove high-frequency interference signals.

[0034] The third Hall signal backflow prevention unit includes a fourth diode D4. The positive terminal of the fourth diode D4 is connected to the second terminal of the sixth filter resistor R6, and the negative terminal of the fourth diode D4 is connected to the Hall sensor interface J1, specifically the Hall sensor input signal terminal HC of the Hall sensor interface J1. Due to the unidirectional conductivity of the fourth diode D4, high voltage backflow to the output terminal of the signal filter can be prevented, thus avoiding damage to the circuit and its brushless motor driver.

[0035] In order to provide a high-level signal, pull-up resistors are respectively provided between the first filter unit and the first Hall signal backflow prevention unit, between the second filter unit and the second Hall signal backflow prevention unit, and between the third filter unit and the third Hall signal backflow prevention unit.

[0036] Specifically, the pull-up resistors include a first resistor R1, a third resistor R3, and a fifth resistor R5. The first terminal of the first resistor R1 is connected to a high voltage level of +5V, and the second terminal is connected to the anode of the second diode D2. The first terminal of the third resistor R3 is connected to a high voltage level of +5V, and the second terminal is connected to the anode of the third diode D3. The first terminal of the fifth resistor R5 is connected to a high voltage level of +5V, and the second terminal is connected to the anode of the fourth diode D4.

[0037] In addition, this circuit includes a Hall sensor power supply reverse current protection diode, namely the first diode D1. The positive terminal of the Hall sensor power supply reverse current protection diode is connected to the high level +5V, and the negative terminal is connected to the positive power supply HVCC of the Hall sensor interface. After the high voltage phase line of the motor is short-circuited to the positive power supply HVCC of J1, the unidirectional conductivity of the first diode D1 can prevent the high voltage from flowing back to the power supply +5V, thus avoiding damage to the circuit and its brushless motor driver.

[0038] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this application can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this application can be achieved, and this is not limited herein.

[0039] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0040] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A protection circuit for a Hall sensor interface of a brushless motor driver, characterized in that, It includes a first sub-circuit, a second sub-circuit, and a third sub-circuit; The first sub-circuit includes a first filter unit and a first Hall signal backflow prevention unit connected in sequence, with the first filter unit connected to the first output terminal of the Hall signal; the second sub-circuit includes a second filter unit and a second Hall signal backflow prevention unit connected in sequence, with the second filter unit connected to the second output terminal of the Hall signal; the third sub-circuit includes a third filter unit and a third Hall signal backflow prevention unit connected in sequence, with the third filter unit connected to the third output terminal of the Hall signal; the first Hall signal backflow prevention unit, the second Hall signal backflow prevention unit, and the third Hall signal backflow prevention unit are respectively connected to the Hall sensor interface.

2. A brushless motor driver Hall sensor interface protection circuit according to claim 1, wherein, The first filter unit, the second filter unit, and the third filter unit are RC filter units.

3. A brushless motor driver Hall sensor interface protection circuit according to claim 2, wherein, The first filtering unit includes a first filtering capacitor and a second filtering resistor. The first end of the first filtering capacitor is grounded, and the second end of the first filtering capacitor and the first end of the second filtering resistor are connected to the first output terminal of the Hall signal.

4. A brushless motor driver Hall sensor interface protection circuit according to claim 3, wherein, The first Hall signal backflow prevention unit includes a second diode, the positive terminal of which is connected to the second end of the second filter resistor, and the negative terminal of which is connected to the Hall sensor interface.

5. A brushless motor driver Hall sensor interface protection circuit according to claim 2, wherein, The second filtering unit includes a second filtering capacitor and a fourth filtering resistor. The first end of the second filtering capacitor is grounded, and the second end of the second filtering capacitor and the first end of the fourth filtering resistor are connected to the second output terminal of the Hall signal.

6. The brushless motor driver Hall sensor interface protection circuit according to claim 5, characterized in that, The second Hall signal backflow prevention unit includes a third diode, the positive terminal of which is connected to the second end of the fourth filter resistor, and the negative terminal of which is connected to the Hall sensor interface.

7. A brushless motor driver Hall sensor interface protection circuit according to claim 2, wherein, The third filtering unit includes a third filtering capacitor and a sixth filtering resistor. The first end of the third filtering capacitor is grounded, and the second end of the third filtering capacitor and the first end of the sixth filtering resistor are connected to the third output terminal of the Hall signal.

8. A brushless motor driver Hall sensor interface protection circuit according to claim 7, wherein, The third Hall signal anti-backflow unit includes a fourth diode, the positive terminal of which is connected to the second end of the sixth filter resistor, and the negative terminal of which is connected to the Hall sensor interface.

9. A brushless motor driver Hall sensor interface protection circuit according to claim 1, wherein, Pull-up resistors are respectively provided between the first filter unit and the first Hall signal backflow prevention unit, between the second filter unit and the second Hall signal backflow prevention unit, and between the third filter unit and the third Hall signal backflow prevention unit.

10. The brushless motor driver Hall sensor interface protection circuit of claim 1, wherein, It also includes a Hall sensor power supply anti-backflow diode, wherein the positive terminal of the Hall sensor power supply anti-backflow diode is connected to a high level, and the negative terminal of the Hall sensor power supply anti-backflow diode is connected to the Hall sensor interface.

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