Unibus communication circuit for brushless motor controller

Abstract

The utility model relates to a monobus communication circuit used for a brushless motor controller, comprising an MCU of a battery pack and an MCU of a motor controller, a signal line DATA is connected between the MCU of the battery pack and the MCU of the motor controller, the MCU of the battery pack comprises a field effect transistor Q1, a field effect transistor Q3, a first switch module and a first diode module, the field effect transistor Q1 is connected with the first switch module, and the field effect transistor Q3 is connected with the first diode module. The MCU of the motor controller comprises a field effect transistor Q2, a field effect transistor Q4, a second switch module and a second diode module. The first diode module is connected with the second diode module through the signal line DATA. According to the utility model, communication between the MCU of the battery pack and the MCU of the motor controller can be realized through one signal line DATA.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic control, in particular to a single-bus communication circuit for a brushless motor controller. Background Art

[0002] The brushless motors used in vacuum cleaner products are generally paired with lithium battery packs, and data needs to be exchanged in some application scenarios. The existing communication methods between brushless motor controllers and lithium battery packs are usually relatively complex. The most important problem is that they occupy relatively many interfaces. Specifically, since the brushless motor controller and the lithium battery pack use traditional UART serial communication, at least three interfaces are required, namely the signal transmission end TXD, the signal reception end RXD, and GND. And both the receiving party and the sending party need to use these three interfaces to achieve communication. The brushless motor controller usually uses a 4-pin interface, and adding the communication function will directly occupy three interfaces, resulting in the inability to implement other conventional functions such as measuring the running speed of the motor due to insufficient interfaces.

[0003] Therefore, it is urgent to improve the design of the communication circuit between the brushless motor and the lithium battery pack, and occupy as few chip interfaces as possible to ensure that there are enough interfaces to implement other functions. Summary of the Utility Model

[0004] For this reason, the technical problem to be solved by the utility model is to overcome the problem that the communication between the brushless motor and the lithium battery pack in the prior art occupies relatively many interfaces.

[0005] To solve the above technical problem, the utility model provides a single-bus communication circuit for a brushless motor controller, including the MCU of the battery pack and the MCU of the motor controller. A signal line DATA is connected between the MCU of the battery pack and the MCU of the motor controller. Among them,

[0006] The MCU of the battery pack includes a field effect transistor Q1, a field effect transistor Q3, a first switch module, and a first diode module. The source electrode of the field effect transistor Q1 is connected to the signal power supply VCC. The drain electrode of the field effect transistor Q1 includes a first branch and a second branch. The first branch of the field effect transistor Q1 is connected to the drain electrode of the field effect transistor Q3. The gate electrode of the field effect transistor Q1 is connected to the signal output control circuit inside the MCU of the battery pack. The gate electrode of the field effect transistor Q3 is connected to the signal output control circuit inside the MCU of the battery pack. The source electrode of the field effect transistor Q3 is grounded. One end of the first switch module is connected to the signal power supply VCC and the other end is grounded. The first switch module is also connected to the second branch of the field effect transistor Q1 to form a first connection node, and the first connection node is connected to the first diode module. Among them, the signal output control circuit inside the MCU of the battery pack is used to output a high level or a low level to the field effect transistor Q1 and the field effect transistor Q3.

[0007] The MCU of the motor controller includes a field effect transistor Q2, a field effect transistor Q4, a second switching module, and a second diode module. The source of the field effect transistor Q2 is connected to the signal power supply VCC. The drain of the field effect transistor Q2 includes a first branch and a second branch. The first branch of the field effect transistor Q2 is connected to the drain of the field effect transistor Q4. The gate of the field effect transistor Q2 is connected to the signal output control loop inside the MCU of the motor controller. The gate of the field effect transistor Q4 is connected to the signal output control loop inside the MCU of the motor controller. The source of the field effect transistor Q4 is grounded. One end of the second switching module is connected to the signal power supply VCC and the other end is grounded. The second switching module is also connected to the second branch of the field effect transistor Q2 to form a second connection node, and the second connection node is connected to the second diode module. Among them, the signal output control loop inside the MCU of the motor controller is used to output a high level or a low level to the field effect transistor Q2 and the field effect transistor Q4;

[0008] The first diode module is connected to the second diode module through the signal line DATA.

[0009] In an embodiment of the present invention, the first diode module includes a diode D2 and a diode D5. The negative electrode of the diode D2 is connected to the signal power supply VCC. The positive electrode of the diode D2 is connected to the negative electrode of the diode D5. The positive electrode of the diode D5 is grounded.

[0010] In an embodiment of the present invention, the second diode module includes a diode D3 and a diode D6. The negative electrode of the diode D3 is connected to the signal power supply VCC. The positive electrode of the diode D3 is connected to the negative electrode of the diode D6. The positive electrode of the diode D6 is grounded.

[0011] In an embodiment of the present invention, the positive electrode of the diode D2 is connected to the negative electrode of the diode D5 to form a third connection node, and the third connection node is connected to the first connection node;

[0012] The positive electrode of the diode D3 is connected to the negative electrode of the diode D6 to form a fourth connection node, and the fourth connection node is connected to the second connection node;

[0013] The third connection node is also connected to the fourth connection node through a diode D4 to form the signal line DATA.

[0014] In an embodiment of the present utility model, the third connection node is connected to the positive electrode of the diode D4, the negative electrode of the diode D4 is connected to the fourth connection node, and one end of a resistor R2 is also connected between the third connection node and the positive electrode of the diode D4, and the other end of the resistor R2 is used to receive the voltage output by the MCU of the motor controller.

[0015] In an embodiment of the present utility model, the first switch module includes a resistor R3, a resistor R4, a resistor R7, a resistor R8, a parallel switch S2 and a parallel switch S4. One ends of the resistor R3 and the resistor R4 are both connected to the signal power supply VCC. The other ends of the resistor R3 and the resistor R4 are respectively connected to one ends of the resistor R7 and the resistor R8 through the parallel switch S2, and the other ends of the resistor R7 and the resistor R8 are grounded after passing through the parallel switch S4;

[0016] After the parallel switch S2 is respectively connected to one end of the resistor R7, it is also connected to the second branch of the field effect transistor Q1 to form a first connection node.

[0017] In an embodiment of the present utility model, the second switch module includes a resistor R5, a resistor R6, a resistor R9, a resistor R10, a parallel switch S1 and a parallel switch S3. One ends of the resistor R5 and the resistor R6 are both connected to the signal power supply VCC. The other ends of the resistor R5 and the resistor R6 are respectively connected to one ends of the resistor R9 and the resistor R10 through the parallel switch S1, and the other ends of the resistor R9 and the resistor R10 are grounded after passing through the parallel switch S3;

[0018] After the parallel switch S1 is connected to one end of the resistor R10, it is also connected to the second branch of the field effect transistor Q2 to form a second connection node.

[0019] In an embodiment of the present utility model, both the field effect transistor Q1 and the field effect transistor Q2 are P-channel enhancement type field effect transistors.

[0020] In an embodiment of the present utility model, both the field effect transistor Q3 and the field effect transistor Q4 are N-channel enhancement type field effect transistors.

[0021] The above technical solution of the present utility model has the following advantages compared with the prior art:

[0022] The single-bus communication circuit for the brushless motor controller of the present utility model can realize the communication between the MCU of the battery pack and the MCU of the motor controller only through one signal line DATA, without occupying other interfaces, thereby ensuring that there are enough interfaces available for other functions;

[0023] The single - bus communication circuit designed for the brushless motor controller in the utility model is simple and highly practical, and is easy to be popularized on a large scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to make the content of the utility model easier to be clearly understood, the following further details the utility model according to the specific embodiments of the utility model and in combination with the drawings, where

[0025] Figure 1 is the single - bus communication circuit diagram for the brushless motor controller in the embodiment of the utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The following further illustrates the utility model in combination with the drawings and specific embodiments, so that those skilled in the art can better understand the utility model and be able to implement it, but the embodiments cited do not limit the utility model.

[0027] Referring to Figure 1 as shown, the utility model relates to a single - bus communication circuit for a brushless motor controller, including the MCU of the battery pack and the MCU of the motor controller. A signal line DATA is connected between the MCU of the battery pack and the MCU of the motor controller. It should be noted that in actual use, the battery pack and the motor controller are also connected through their respective positive power lines and negative power lines, where

[0028] The MCU of the battery pack includes a field - effect transistor Q1, a field - effect transistor Q3, a first switch module, and a first diode module. The source of the field - effect transistor Q1 is connected to the signal power supply VCC. The drain of the field - effect transistor Q1 includes a first branch and a second branch. The first branch of the field - effect transistor Q1 is connected to the drain of the field - effect transistor Q3. The gate of the field - effect transistor Q1 is connected to the signal output control circuit inside the MCU of the battery pack. The gate of the field - effect transistor Q3 is connected to the signal output control circuit inside the MCU of the battery pack. The source of the field - effect transistor Q3 is grounded. One end of the first switch module is connected to the signal power supply VCC and the other end is grounded. The first switch module is also connected to the second branch of the field - effect transistor Q1 to form a first connection node, and the first connection node is connected to the first diode module.

[0029] It should be noted that the signal output control circuit ( Figure 1 corresponding to outputcontrol therein) inside the MCU of the battery pack is used to output a high level or a low level to the field - effect transistor Q1 and the field - effect transistor Q3.

[0030] The MCU of the motor controller includes a field-effect transistor Q2, a field-effect transistor Q4, a second switch module, and a second diode module. The source of the field-effect transistor Q2 is connected to the signal power supply VCC. The drain of the field-effect transistor Q2 includes a first branch and a second branch. The first branch of the field-effect transistor Q2 is connected to the drain of the field-effect transistor Q4. The gate of the field-effect transistor Q2 is connected to the signal output control circuit inside the MCU of the motor controller. The gate of the field-effect transistor Q4 is connected to the signal output control circuit inside the MCU of the motor controller. The source of the field-effect transistor Q4 is grounded. The second switch module is connected to the second branch of the field-effect transistor Q2. One end of the second switch module is connected to the signal power supply VCC and the other end is grounded. The second switch module is also connected to the second branch of the field-effect transistor Q2 to form a second connection node, and the second connection node is connected to the second diode module.

[0031] It should be noted that the signal output control circuit ( Figure 1 corresponding to outputcontrol in it) inside the MCU of the motor controller is used to output a high level or a low level to the field-effect transistor Q2 and the field-effect transistor Q4.

[0032] The first diode module is connected to the second diode module through the signal line DATA.

[0033] Further, the first diode module includes a diode D2 and a diode D5 (functions of the diodes D2 and D5: protect the port. When there is a positive high voltage, it first flows to the diode D2. When there is a negative high voltage, it first flows to the diode D5. This can prevent the port from being damaged). The negative electrode of the diode D2 is connected to the signal power supply VCC. The positive electrode of the diode D2 is connected to the negative electrode of the diode D5. The positive electrode of the diode D5 is grounded.

[0034] Further, the second diode module includes a diode D3 and a diode D6 (functions of the diodes D3 and D6: protect the port. When there is a positive high voltage, it first flows to the diode D3. When there is a negative high voltage, it first flows to the diode D6. This can prevent the port from being damaged). The negative electrode of the diode D3 is connected to the signal power supply VCC. The positive electrode of the diode D3 is connected to the negative electrode of the diode D6. The positive electrode of the diode D6 is grounded.

[0035] Further, the positive electrode of the diode D2 is connected to the negative electrode of the diode D5 to form a third connection node, and the third connection node is connected to the first connection node. The positive electrode of the diode D3 is connected to the negative electrode of the diode D6 to form a fourth connection node, and the fourth connection node is connected to the second connection node. The third connection node is also connected to the fourth connection node through a diode D4 to form the signal line DATA.

[0036] Further, the third connection node is connected to the positive electrode of the diode D4, the negative electrode of the diode D4 is connected to the fourth connection node, and one end of a resistor R2 is also connected between the third connection node and the positive electrode of the diode D4, and the other end of the resistor R2 is used to receive the voltage (+5V) output by the MCU of the motor controller.

[0037] Further, the first switch module includes resistors R3, R4, R7, R8, parallel switch S2 and parallel switch S4 (resistors R3 and R4 are pull-up resistors, and resistors R7 and R8 are pull-down resistors). One end of both the resistor R3 and the resistor R4 is connected to the signal power supply VCC. The other ends of the resistor R3 and the resistor R4 are respectively connected to one end of the resistor R7 and the resistor R8 through the parallel switch S2. The other ends of the resistor R7 and the resistor R8 are grounded after passing through the parallel switch S4. After the parallel switch S2 is respectively connected to one end of the resistor R7, it is also connected to the second branch of the field effect transistor Q1 to form a first connection node.

[0038] Further, the second switch module includes resistors R5, R6, R9, R10, parallel switch S1 and parallel switch S3 (resistors R5 and R6 are pull-up resistors, and resistors R9 and R10 are pull-down resistors). One end of both the resistor R5 and the resistor R6 is connected to the signal power supply VCC. The other ends of the resistor R5 and the resistor R6 are respectively connected to one end of the resistor R9 and the resistor R10 through the parallel switch S1. The other ends of the resistor R9 and the resistor R10 are grounded after passing through the parallel switch S3. After the parallel switch S1 is respectively connected to one end of the resistor R10, it is connected to the second branch of the field effect transistor Q2 to form a second connection node.

[0039] Further, both the field effect transistor Q1 and the field effect transistor Q2 are P-channel enhancement mode field effect transistors; both the field effect transistor Q3 and the field effect transistor Q4 are N-channel enhancement mode field effect transistors.

[0040] The principle of this embodiment is introduced in detail as follows:

[0041] The MCU of the motor controller receives data: The pin of the signal line DATA connected to the MCU of the motor controller needs to be configured as a pull-down input mode (pull-down means the initial level is low level). The required signal path is as follows: The parallel switch S1 connected to the lower ends of the pull-up resistors R5 and R6 where the signal power supply VCC is located is disconnected, and the switch S3 connected to the lower ends of the pull-down resistors R9 and R10 is closed. Since the pin of the signal line DATA is in the pull-down input mode, the motor controller receives an initial state of low level through the signal line DATA. When the MCU of the battery pack sends a low level, the current on the pull-up resistor R2 will flow to the MCU of the battery pack, and the lower end of the pull-up resistor R2 can be regarded as grounded (GND), and the diode D4 is cut off, and the MCU of the motor controller receives a low level. When the MCU of the battery pack sends a high level, the lower end of the pull-up resistor R2 can be regarded as 5V, the diode D4 is turned on, and the MCU of the motor controller receives a high level.

[0042] The MCU of the motor controller sends data: The pin of the signal line DATA connected to the MCU of the motor controller needs to be configured as an output mode, and high and low levels are output to two different field effect transistors Q2 and Q4 through the signal output control loop inside the MCU; if the signal output control loop outputs a high level, the field effect transistor Q4 is turned on and outputs a low level; if the signal output control loop outputs a low level, the field effect transistor Q2 is turned on and outputs a high level. When the MCU of the motor controller sends a low level, the diode D4 is forward-connected to the pull-up resistor R2 and 5V, and the negative side is connected to the low level. According to the working principle of the diode that conducts forward and cuts off backward, the diode D4 is turned on, and the current will flow through the pull-up resistor R2 and the diode D4 to the MCU of the motor controller, then the MCU of the battery pack receives a low level; when the MCU of the motor controller sends a high level, the diode D4 is cut off, and the current on the pull-up resistor R2 will flow to the MCU of the battery pack, and the MCU of the battery pack receives a high level (i.e., the voltage of the signal power supply VCC).

[0043] The MCU of the battery pack sends data: The pin of the signal line DATA connected to the MCU of the battery pack needs to be configured as an output mode, and high and low levels are output to two different field effect transistors Q1 and Q3 through the signal output control loop inside the MCU; if the signal output control loop outputs a high level, the field effect transistor Q3 is turned on and outputs a low level; if the signal output control loop outputs a low level, the field effect transistor Q1 is turned on and outputs a high level. When the MCU of the battery pack sends a low level, the current on the pull-up resistor R2 will flow to the MCU of the battery pack, and the lower end of the pull-up resistor R2 can be regarded as GND, and the diode D4 is cut off, and the MCU of the motor controller receives a low level; when the MCU of the battery pack sends a high level, the lower end of the pull-up resistor R2 can be regarded as 5V, the diode D4 is turned on, and the MCU of the motor controller receives a high level.

[0044] The MCU of the battery pack receives data: It is necessary to configure the pin of the signal line DATA connected to the MCU of the battery pack as the input mode. When the MCU of the motor controller sends a high level, the diode D4 is cut off, and the current on the pull-up resistor R2 will flow to the MCU of the battery pack, and the MCU of the battery pack receives a high level (i.e., the voltage of the signal power supply VCC); when the MCU of the motor controller sends a low level, the diode D4 is forward-connected to the pull-up resistor R2 and 5V, and the negative is connected to the low level. According to the working principle of the diode that conducts forward and cuts off reverse, the diode D4 conducts, and the current will flow through the pull-up resistor R2 and the diode D4 to the MCU of the motor controller, then the MCU of the battery pack receives a low level. In addition, the diode D4 can prevent the current from flowing back into the MCU pin of the battery pack when the MCU of the motor controller sends data.

[0045] Obviously, the above embodiments are only examples for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present utility model.

Claims

1. A single-bus communication circuit for a brushless motor controller, characterized in that: An MCU of a battery pack and an MCU of a motor controller, a signal line DATA is connected between the MCU of the battery pack and the MCU of the motor controller, wherein, The MCU of the battery pack includes a field effect transistor Q1, a field effect transistor Q3, a first switch module and a first diode module. The source of the field effect transistor Q1 is connected to the signal power supply VCC. The drain of the field effect transistor Q1 includes a first branch and a second branch. The first branch of the field effect transistor Q1 is connected to the drain of the field effect transistor Q3. The gate of the field effect transistor Q1 is connected to a signal output control circuit inside the MCU of the battery pack. The gate of the field effect transistor Q3 is connected to the signal output control circuit inside the MCU of the battery pack. The source of the field effect transistor Q3 is grounded. One end of the first switch module is connected to the signal power supply VCC and the other end is grounded. The first switch module is also connected to the second branch of the field effect transistor Q1 to form a first connection node, and the first connection node is connected to the first diode module. Wherein, the signal output control circuit inside the MCU of the battery pack is used to output a high level or a low level to the field effect transistor Q1 and the field effect transistor Q3; The MCU of the motor controller includes a field effect transistor Q2, a field effect transistor Q4, a second switch module and a second diode module. The source of the field effect transistor Q2 is connected to the signal power supply VCC. The drain of the field effect transistor Q2 includes a first branch and a second branch. The first branch of the field effect transistor Q2 is connected to the drain of the field effect transistor Q4. The gate of the field effect transistor Q2 is connected to a signal output control circuit inside the MCU of the motor controller. The gate of the field effect transistor Q4 is connected to the signal output control circuit inside the MCU of the motor controller. The source of the field effect transistor Q4 is grounded. One end of the second switch module is connected to the signal power supply VCC and the other end is grounded. The second switch module is also connected to the second branch of the field effect transistor Q2 to form a second connection node, and the second connection node is connected to the second diode module. Wherein, the signal output control circuit inside the MCU of the motor controller is used to output a high level or a low level to the field effect transistor Q2 and the field effect transistor Q4; The first diode module is connected to the second diode module through the signal line DATA.

2. The single-bus communication circuit for a brushless motor controller according to claim 1, characterized in that: The first diode module includes a diode D2 and a diode D5. The negative electrode of the diode D2 is connected to the signal power supply VCC. The positive electrode of the diode D2 is connected to the negative electrode of the diode D5. The positive electrode of the diode D5 is grounded.

3. The single-bus communication circuit for a brushless motor controller according to claim 2, characterized in that: The second diode module includes a diode D3 and a diode D6. The negative electrode of the diode D3 is connected to the signal power supply VCC. The positive electrode of the diode D3 is connected to the negative electrode of the diode D6. The positive electrode of the diode D6 is grounded.

4. The single-bus communication circuit for a brushless motor controller according to claim 3, characterized in that: The positive electrode of the diode D2 is connected to the negative electrode of the diode D5 to form a third connection node, and the third connection node is connected to the first connection node; The positive electrode of the diode D3 is connected to the negative electrode of the diode D6 to form a fourth connection node, and the fourth connection node is connected to the second connection node; The third connection node is also connected to the fourth connection node through the diode D4 to form the signal line DATA.

5. The single-bus communication circuit for a brushless motor controller according to claim 4, characterized in that: The third connection node is connected to the positive electrode of the diode D4, the negative electrode of the diode D4 is connected to the fourth connection node, and one end of the resistor R2 is also connected between the third connection node and the positive electrode of the diode D4, and the other end of the resistor R2 is used to receive the voltage output by the MCU of the motor controller.

6. The single-bus communication circuit for a brushless motor controller according to claim 1, wherein: The first switch module includes a resistor R3, a resistor R4, a resistor R7, a resistor R8, a parallel switch S2 and a parallel switch S4. One ends of the resistor R3 and the resistor R4 are both connected to the signal power supply VCC. The other ends of the resistor R3 and the resistor R4 are respectively connected to one ends of the resistor R7 and the resistor R8 through the parallel switch S2. The other ends of the resistor R7 and the resistor R8 are grounded after passing through the parallel switch S4; After the parallel switch S2 is connected to one end of the resistor R7, it is also connected to the second branch of the field effect transistor Q1 to form a first connection node.

7. The single-bus communication circuit for a brushless motor controller according to claim 1, characterized in that: The second switch module includes a resistor R5, a resistor R6, a resistor R9, a resistor R10, a parallel switch S1 and a parallel switch S3. One ends of the resistor R5 and the resistor R6 are both connected to the signal power supply VCC. The other ends of the resistor R5 and the resistor R6 are respectively connected to one ends of the resistor R9 and the resistor R10 through the parallel switch S1. The other ends of the resistor R9 and the resistor R10 are grounded after passing through the parallel switch S3; After the parallel switch S1 is connected to one end of the resistor R10, it is also connected to the second branch of the field effect transistor Q2 to form a second connection node.

8. The single-bus communication circuit for a brushless motor controller according to claim 1, characterized in that: Both the field effect transistor Q1 and the field effect transistor Q2 are P-channel enhancement type field effect transistors.

9. The single-bus communication circuit for a brushless motor controller according to claim 1, characterized in that: Both the field effect transistor Q3 and the field effect transistor Q4 are N-channel enhancement type field effect transistors.

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