CN214623340U

CN214623340U - Communication circuit and household appliance

Info

Publication number: CN214623340U
Application number: CN202120193630.0U
Authority: CN
Inventors: 朱彪
Original assignee: Shenzhen Hetai Intelligent Home Appliance Controller Co ltd
Current assignee: Shenzhen Hetai Intelligent Home Appliance Controller Co ltd; Shenzhen H&T Intelligent Control Co Ltd
Priority date: 2021-01-22
Filing date: 2021-01-22
Publication date: 2021-11-05
Anticipated expiration: 2031-01-22

Abstract

The embodiment of the utility model discloses communication circuit and domestic appliance, communication circuit include first circuit and second circuit, and the first circuit includes: the first receiving module is used for receiving the voltage signal on the first connecting point, the second circuit comprises a second sending module, a second receiving module, a voltage conversion module and a second connecting point, the second sending module is used for transmitting the voltage signal corresponding to the second signal sent by the second control unit to the second connecting point, the second receiving module is used for receiving the voltage signal on the second connecting point, and the voltage conversion module is used for receiving the first power supply on the second connecting point. Through the mode, the communication process of the main control board and the operation board can be realized through fewer connecting wires, and the cost is lower.

Description

Communication circuit and household appliance

Technical Field

The utility model relates to an electronic circuit technical field especially relates to a communication circuit and domestic appliance.

Background

In the electronic technology application, a process of serial communication between the main control board and the operation board needs to be realized through wiring, and usually 4 wires are needed to realize the serial communication. When the distance between the main control board and the operation board is too long, the voltage on the connection line between the main control board and the operation board is too high, and thus, the operation board does not have enough voltage to work and communicate normally.

Therefore, in the prior art, a communication chip is usually required to be added to realize normal communication. However, the cost is increased by adding a chip, and the cost is further increased by additionally supplying power to the chip whether 4 wires are used or the communication chip is used.

SUMMERY OF THE UTILITY MODEL

The embodiment of the utility model provides a aim at providing a communication circuit and domestic appliance, the utility model discloses can realize the communication process of main control board and operation panel promptly through less connecting wire, the cost is lower.

In order to achieve the above object, in a first aspect, the present invention provides a communication circuit, the communication circuit is configured to be connected to a first control unit on a control panel, a first power source and a second control unit on an operation panel, respectively, and the communication circuit includes:

a first circuit for connection with the first control unit and the first power supply;

the first circuit comprises a first sending module, a first receiving module and a first connecting point;

the first sending module is respectively connected with the first control unit, the first connection point and the first power supply, and the first sending module is used for transmitting a voltage signal corresponding to a first signal sent by the first control unit or the first power supply to the first connection point;

the first receiving module is respectively connected with the first control unit and the first connecting point, and is used for receiving a voltage signal on the first connecting point and sending a level signal corresponding to the voltage signal on the first connecting point to the first control unit;

a second circuit for connection with the second control unit;

the second circuit comprises a second sending module, a second receiving module, a voltage conversion module and a second connection point, wherein the second connection point is used for being connected with the first connection point;

the second sending module is respectively connected with the second control unit and the second connection point, and the second sending module is used for transmitting a voltage signal corresponding to a second signal sent by the second control unit to the second connection point;

the second receiving module is respectively connected with the second control unit and the second connection point, and is used for receiving a voltage signal on the second connection point and sending a level signal corresponding to the voltage signal on the second connection point to the first control unit;

the voltage conversion module is respectively connected with the second control unit and the second connection point, and is configured to receive a first power supply at the second connection point to convert the first power supply into a second power supply, where the second power supply is configured to provide a working voltage for the second sending module and the second receiving module, and a voltage of the first power supply is greater than a voltage of the second power supply.

In an optional manner, the first sending module includes a first switch unit and a second switch unit;

the first switch unit is connected with the first control unit and used for switching on and off states based on the first signal;

the second switch unit is respectively connected with the first switch unit, the first power supply and the first connecting point, and the second switch unit switches the switch state based on the switch state of the first switch unit so as to control the connection state of the first power supply and the first connecting point.

In an optional mode, the first switching unit includes a first switching tube, a first resistor and a second resistor;

the control end of the first switch tube is connected with one end of the first resistor and one end of the second resistor respectively, the other end of the first resistor is connected with the first control unit, the other end of the second resistor is connected with the third power supply, the first end of the first switch tube is grounded, and the second end of the first switch tube is connected with the second switch unit.

In an optional manner, the second switch unit includes a second switch tube, a third resistor, a fourth resistor, and a fifth resistor;

the control end of the second switch tube is respectively connected with the first switch unit and one end of the third resistor, the other end of the third resistor is respectively connected with one end of the fourth resistor and the first power supply, the other end of the fourth resistor is connected with the first end of the second switch tube, the second end of the second switch tube is connected with one end of the fifth resistor, and the other end of the fifth resistor is connected with the first connecting point.

In an optional manner, the first receiving module includes a first zener diode, a third switching tube, and a sixth resistor;

the cathode of the first voltage-stabilizing diode is connected with the first connecting point, the anode of the first voltage-stabilizing diode is connected with the control end of the third switching tube, the first end of the third switching tube is grounded, the second end of the third switching tube is respectively connected with the first control unit and one end of the sixth resistor, and the other end of the sixth resistor is connected with the third power supply.

In an optional manner, the second sending module includes a fourth switching tube, a fifth switching tube and a seventh resistor;

the control end of the fourth switch tube is connected with the second control unit, the first end of the fourth switch tube is connected with the second power supply, the second end of the fourth switch tube is respectively connected with one end of the seventh resistor and the control end of the fifth switch tube, the other end of the seventh resistor is grounded, the first end of the fifth switch tube is grounded, and the second end of the fifth switch tube is connected with the second connecting point.

In an optional manner, the second receiving module includes a first capacitor, a second zener diode, a tenth resistor, a sixth switching tube, and a seventh switching tube;

the one end of first electric capacity with the one end of tenth resistance is all ground connection, the other end of first electric capacity respectively with the negative pole of second zener diode and the second tie point is connected, the positive pole of second zener diode respectively with the other end of tenth resistance and the control end of sixth switch tube is connected, the first end ground connection of sixth switch tube, the second end of sixth switch tube respectively with the second power and the control end of seventh switch tube is connected, the first end ground connection of seventh switch tube, the second end of seventh switch tube respectively with the second power and the second control unit is connected.

In an optional manner, the voltage conversion module includes a fifth diode and a voltage conversion chip;

the anode of the fifth diode is connected with the second connection point, the cathode of the fifth diode is connected with the input end of the voltage conversion chip, and the output end of the voltage conversion chip is connected with the second sending module and the second receiving module respectively.

In an optional mode, the second circuit further comprises an eleventh resistor, and a first diode and a second diode which are connected in series;

the cathode of the first diode is connected with one end of the eleventh resistor, the second sending module, the second receiving module and the voltage conversion module respectively, a connection point between the anode of the first diode and the cathode of the second diode is connected with the second connection point, and the cathode of the second diode, the cathode of the first diode and the other end of the eleventh resistor are all grounded.

In a second aspect, an embodiment of the present invention further provides a household appliance, where the household appliance includes a control board, an operation board, and the communication circuit as described above;

the communication circuit is respectively connected with the control panel and the operation panel and is used for realizing the data transmission process and the power supply process between the control panel and the operation panel.

The embodiment of the utility model provides a beneficial effect is: the utility model provides a communication circuit, communication circuit is used for being connected with the first control unit on the control panel, first power and the second control unit on the operation panel respectively, communication circuit includes first circuit and second circuit, first circuit is used for being connected with first control unit and the first power, first circuit includes first sending module, first receiving module and first connecting point, first sending module is connected with first control unit, first connecting point and first power respectively, first sending module is used for transmitting the voltage signal or the first power that the first signal that first control unit sent corresponds to first connecting point, first receiving module is connected with first control unit and first connecting point respectively, first receiving module is used for receiving the voltage signal on the first connecting point, and send the level signal that the voltage signal on the first connecting point corresponds to first control unit, the second circuit is used for being connected with the second control unit, the second circuit comprises a second sending module, a second receiving module, a voltage conversion module and a second connection point, wherein the second connection point is used for being connected with the first connection point, the second sending module is respectively connected with the second control unit and the second connection point, the second sending module is used for transmitting a voltage signal corresponding to a second signal sent by the second control unit to the second connection point, the second receiving module is respectively connected with the second control unit and the second connection point, the second receiving module is used for receiving the voltage signal on the second connection point and sending a level signal corresponding to the voltage signal on the second connection point to the first control unit, the voltage conversion module is respectively connected with the second control unit and the second connection point, the voltage conversion module is used for receiving a first power supply on the second connection point so as to convert the first power supply into a second power supply, the second power supply is used for providing working voltage for the second sending module and the second receiving module. Therefore, when the control board sends a signal to the operation board, the first sending module can transmit a voltage signal corresponding to the first signal sent by the first control unit to the first connection point, and the second receiving module can obtain a corresponding voltage signal from the first connection point through the second connection point and send a level signal corresponding to the voltage signal to the second control unit; when the operating panel sends a signal to the control panel, the second sending module can transmit a voltage signal corresponding to the second signal sent by the second control unit to the second connection point, and the first receiving module can obtain a corresponding voltage signal from the second connection point through the first connection point and send a level signal corresponding to the voltage signal to the first control unit; and the control panel accessible first sending module transmits first power to first tie point, and then voltage transformation module accessible second tie point acquires first power from first tie point, and convert first power into the second power to for second sending module and second receiving module provide operating voltage, data exchange process and the power supply process in the communication process of main control panel and operation panel are realized promptly through using less connecting wire to the aforesaid mode, and the cost is lower.

Drawings

One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the figures in which like reference numerals refer to similar elements and which are not to scale unless otherwise specified.

Fig. 1 is a block diagram of a household appliance according to an embodiment of the present invention;

fig. 2 is a block diagram of a household appliance according to another embodiment of the present invention;

fig. 3 is a block diagram of a household appliance according to another embodiment of the present invention;

fig. 4 is a block diagram of a connection structure between a control board and an operation board according to an embodiment of the present invention;

fig. 5 is a block diagram illustrating a connection structure between a control board and an operation board according to another embodiment of the present invention;

fig. 6 is a schematic circuit diagram of a first circuit according to an embodiment of the present invention;

fig. 7 is a schematic circuit diagram of a second circuit according to an embodiment of the present invention;

fig. 8 is a schematic circuit diagram of a first circuit according to another embodiment of the present invention;

fig. 9 is a schematic circuit diagram of a second circuit according to another embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

Referring to fig. 1, fig. 1 is a block diagram of a household appliance according to an embodiment of the present invention. As shown in fig. 1, the household appliance includes a communication circuit 10, a control board 20 and an operation board 30, wherein the communication circuit 10 is connected to the control board 20 and the operation board 30 respectively.

Specifically, the communication circuit 10 is used to implement a data transmission process and a power supply process between the control board 20 and the operation board 30. That is, the control board 20 can send data to the operation board 30 through the communication circuit 10, and the operation board 30 can send data to the control board 20 through the communication circuit 10, and at the same time, the control board 20 can provide input power to the operation board 30 through the communication circuit 10.

As shown in fig. 2, the communication circuit 10 includes a first circuit 11 and a second circuit 12, the control board 20 includes a first control unit 21 and a first power source 22, and the operation board 30 includes a second control unit 31. The first circuit 11 is connected to the first control unit 21 and the first power supply 22, and the second circuit 12 is connected to the second control unit 31.

In practical applications, when the control board 20 needs to send data to the operation board 30, the first control unit 21 outputs a voltage signal corresponding to a first signal after passing through the first circuit 11, and the voltage signal is transmitted to the second circuit 12 through a connection line between the first circuit 11 and the second circuit 12. Then, the second circuit 12 sends the level signal corresponding to the received voltage signal to the second control unit 31, and the second control unit 31 can identify the content sent by the first control unit 21 according to the level signal.

When the operation panel 30 needs to transmit data to the control panel 20, the second control unit 31 outputs a second signal to be transmitted to the second circuit 12 and then outputs a voltage signal corresponding to the second signal, and the voltage signal is transmitted to the first circuit 11 through a connection line between the second circuit 12 and the first circuit 11. Then, the first circuit 11 sends the level signal corresponding to the received voltage signal to the first control unit 21, and the first control unit 21 can identify the content sent by the second control unit 31 according to the level signal.

When the control board 20 provides input power for the operation board 30, the first control unit 21 outputs the first power 22 to be transmitted through the first circuit 11, and the first power 22 is transmitted to the second circuit 12 through the connection line between the first circuit 11 and the second circuit 12. Then, the second circuit 12 obtains the required operating voltage to the second circuit 12 according to the received first power source, so as to supply power to each module in the second circuit 12. It should be noted that the hardware structure of the household appliance shown in fig. 2 is only an example, and in the above embodiment, the first circuit 11 and the second circuit 12 are two circuit modules that exist independently of the control board 20 and the operation board 30, respectively.

In other embodiments, as shown in fig. 3, the first circuit 11 may be integrated in the control board 20, and the second circuit 12 may be integrated in the operation board 30. That is, the communication and power supply processes between the control board 20 and the operation board 30 can be directly realized through the connection line between the first circuit 11 and the second circuit 12 without adding other hardware structures.

As shown in fig. 4, the first circuit 11 includes a first transmitting module 111, a first receiving module 112 and a first connection point S1. The second circuit 12 includes a second transmitting module 121, a second receiving module 122, a voltage converting module 123 and a second connection point S2, and the second connection point S2 is used for connecting to the first connection point S1.

The first transmitting module 111 is connected to the first control unit 21, the first power source 22 and the first connection point S1, and the first receiving module 112 is connected to the first control unit 21 and the first connection point S1. The second transmitting module 121 is connected to the second control unit 31 and the second connection point S2, the second receiving module 122 is connected to the second control unit 31 and the second connection point S2, and the voltage converting module 123 is connected to the second control unit 31 and the second connection point S2.

Specifically, when the control board 20 needs to transmit data to the operation board 30, the first control unit 21 outputs a voltage signal corresponding to the first signal after passing through the first transmitting module 111, and the first transmitting module 111 transmits the voltage signal to the first connection point S1.

In an embodiment, referring to fig. 5 in combination with fig. 4, the first sending module 111 includes a first switch unit 1111 and a second switch unit 1112, wherein the first switch unit 1111 is connected to the first control unit 21, and the second switch unit 1112 is respectively connected to the first switch unit 1111, the first power source 22 and the first connection point S1.

The first switch unit 1111 is configured to switch a switch state of a first signal to be transmitted based on the first control unit 21; the second switch unit 1112 switches a switch state based on the switch state of the first switch unit 1111 to control a connection state of the first power source 22 and the first connection point S1. It can be understood that the switch states of the first switch unit 1111 and the second switch unit 1112 each include a connection state and a disconnection state.

When the first switch unit 1111 is controlled to be in the on state by the first signal sent by the first control unit 21, the second control unit 1112 is also in the on state, the first power source 22 can be connected to the first connection point S1 through the second control unit 1112, and the voltage signal at the first connection point S1 is the first power source 22. On the contrary, when the first switch unit 1111 is controlled to be in the off state by the first signal sent by the first control unit 22, the second control unit 1112 is also in the off state, that is, the connection between the first power source 22 and the first connection point S1 is broken, and the voltage signal at the first connection point S1 is 0. It should be understood that the voltage value of the first signal due to the output of the first control unit 21 is generally smaller than the voltage value of the first power supply 22. Therefore, by setting the first signals output by the first power source 22 and the control unit 21 on two different switch units, the first signals output by the first power source 22 and the control unit 21 can be staggered, so that the output terminal of the control unit 21 can be directly connected to the first switch unit 1111 to control the on and off of the first switch unit 1111.

Of course, in another embodiment, the first transmitting module 111 may also employ only one switching unit. However, in this case, it may be necessary to set the voltage value of the first signal output by the control unit 21 to be greater than that of the first power supply 22, and then an additional power conversion circuit is required to boost the voltage value of the first signal, so that the first signal can be used to control the switch unit, which may increase the cost.

Optionally, the first switch unit includes a first switch tube, a first resistor and a second resistor.

The first switch tube can be one of a triode, an MOS tube and an IGBT switch tube.

Taking the example that the first switch tube is selected from a triode, at this time, the base of the triode is the control end of the first switch tube, the emitter of the triode is the first end of the first switch tube, and the collector of the triode is the second end of the first switch tube.

The circuit configuration of the first circuit 11 shown in fig. 6 will be described as an example. The first switch tube corresponds to the transistor Q1, the first resistor corresponds to the resistor R1, and the second resistor corresponds to the resistor R2.

The first switching unit in the first transmitting module 111 further includes a resistor R6. The control end of the triode Q1 is connected to one end of the resistor R1 and one end of the second resistor R2, respectively, the other end of the resistor R1 is connected to the first control unit 21 through the connection point TX1, the other end of the resistor R2 is connected to the third power supply V3, the first end of the switch tube Q1 is grounded through the resistor R6, and the second end of the triode Q1 is connected to the second switch unit 112.

Optionally, the second switch unit includes a second switch tube, a third resistor, a fourth resistor, and a fifth resistor.

Similarly, the second switch tube can be one of a triode, a MOS tube and an IGBT switch tube. And the first switch tube and the second switch tube can be the same or different, for example, the first switch tube and the second switch tube all use triodes.

As shown in fig. 6, the second switch corresponds to the transistor Q2, the third resistor corresponds to the resistor R3, the fourth resistor corresponds to the resistor R4, and the fifth resistor corresponds to the resistor R5.

The second switch unit in the first transmitting module 111 further includes a diode D1 and a diode D2. The control end of the triode Q2 is connected to the second end of the triode Q1 and one end of the resistor R3, the other end of the resistor R3 is connected to one end of the resistor R4, the cathode of the diode D1 and the first power source V1, the other end of the resistor R4 is connected to the first end of the triode Q2, the second end of the triode Q2 is connected to one end of the resistor R5, the other end of the resistor R5 is connected to the anode of the diode D1, the cathode of the diode D2 and the first connection point S1, and the anode of the diode D2 is grounded.

When the first signal sent by the first control unit 21 to the connection point TX1 is a high-level signal, the voltage difference existing between the base and the emitter of the transistor Q1 can make the transistor Q1 conduct. At this time, the first power source V1 is grounded through the resistor R3, the collector and emitter of the transistor Q1, and the resistor R6, so that the voltage at the base of the transistor Q2 is the divided voltage of the first power source V1 on the resistor R6, the voltage at the emitter of the transistor Q2 is the voltage of the first power source V1, and the voltage difference existing between the base and emitter of the transistor Q2 turns on the transistor Q2. The first power source V1 is connected to the first connection point S1 through the resistor R4, the emitter and the collector of the transistor Q2, and the resistor R5, that is, the voltage of the first connection point S1 is the voltage of the first power source V1 passing through the resistor R4 and the resistor R5. If the resistances of the resistor R4 and the resistor R5 are small, the divided voltage is negligible, i.e., the voltage of the first connection point S1 is close to the voltage of the first power source V1.

When the first signal sent by the first control unit 21 to the connection point TX1 is a low-level signal, the base voltage of the switching transistor Q1 is forced to be pulled low, the transistor Q1 and the transistor Q2 are both turned off, and at this time, the connection between the first connection point S1 and the first power source V1 is disconnected.

In summary, when the first signal sent by the first control unit 21 to the connection point TX1 is a high-level signal, the first connection point S1 is connected to the first power source V1, that is, the voltage signal input to the first connection point S1 is the first power source V1; when the first signal sent by the first control unit 21 to the connection point TX1 is a low-level signal, the connection between the first connection point S1 and the first power source V1 is disconnected, and the first power source V1 is not the voltage input to the first connection point S1, that is, the voltage signal input to the first connection point S1 is 0.

It should be understood that the first power source V1 and the third power source V3 are both power sources on the control board 20, and the first power source V1 corresponds to the first power source 22 in the above-mentioned embodiment.

In one embodiment, the first power supply V1 may be set to 12V, the 12V voltage may be converted into 5V through a voltage stabilizing module on the control board 20, and the 5V voltage may be used as the third power supply V3, since the 5V voltage is a power supply voltage commonly used by each module on the control board 20, which can ensure that each module on the control board 20 works normally. Setting the first power source V1 to 12V can ensure enough voltage to realize normal communication between the control board 20 and the operation board 30 when the control board 20 and the operation board 30 are remotely transmitted.

It should be noted that, in another embodiment, only the first switch unit may be selected (without providing the second switch unit), but at this time, the emitter of the transistor Q1 may only be connected to the first power source V1, and the collector of the transistor Q1 needs to be connected to the first connection point S1, so that the input power (i.e., the voltage value corresponding to the signal output by the control unit) of the control terminal of the transistor Q1 needs to be greater than the first power source V1, so that the transistor Q1 may be turned on. However, in practical applications, the voltage of the first power source V1 is usually greater than the power supply voltage commonly used for each module on the control board 20, and at this time, a power source larger than the first power source V1 needs to be obtained through another power source processing circuit, which may increase the cost.

Referring to fig. 6 again, the second connection point S2 obtains the voltage signal through the connection line with the first connection point S1. Then, the second receiving module 122 obtains a corresponding level signal according to the voltage signal, and transmits the level signal to the second control unit 31, and the second control unit 31 can identify the content sent by the first control unit 21 according to the level signal.

Optionally, the second receiving module 122 includes a first capacitor, a second zener diode, a tenth resistor, a sixth switching tube, and a seventh switching tube.

Specifically, a circuit configuration of the second circuit 12 shown in fig. 7 will be described as an example. The first capacitor corresponds to the capacitor C4, the second zener diode corresponds to the zener diode DW2, the tenth resistor corresponds to the resistor R14, the sixth switching tube corresponds to the triode Q6, and the seventh switching tube corresponds to the triode Q7.

The specific type selection and use process of the sixth switching tube and the seventh switching tube are similar to those of the first switching tube and the second switching tube, and are not described herein again.

Optionally, the second receiving module 122 further includes a resistor R15, a resistor R16, a resistor R17, a resistor R18, and a resistor R19.

Specifically, one end of a capacitor C4 and one end of a resistor R14 are both grounded, the other end of a capacitor C4 is connected to the cathode of a zener diode DW2 and the second connection point S2, the anode of a zener diode DW2 is connected to the other end of a resistor R14 and one end of a resistor R15, the other end of the resistor R15 is connected to the base of a transistor Q6, the emitter of the transistor Q6 is grounded, the collector of the transistor Q6 is connected to one end of the resistor R16, one end of a resistor R17 and one end of a resistor R18, the other end of the resistor R16 is connected to a second power supply V2, the other end of the resistor R17 is grounded, the other end of the resistor R18 is connected to the base of a transistor Q7, the emitter of the transistor Q7 is grounded, the collector of the transistor Q7 is connected to one end of a resistor RX2 and one end of a resistor R19, and the other end of the resistor R19 is grounded.

If the voltage signal obtained by the second connection point S2 through the connection line with the first connection point S1 is the first power supply V1, and the first power supply V1 is greater than the regulated voltage value of the zener diode DW2, the first power supply V1 is the base input voltage of the transistor Q6 through the zener diode DW2 and the resistor R15, while the emitter of the transistor Q6 is grounded, and the transistor Q6 is turned on. The base of the transistor Q7 is grounded via the resistor R18 and the collector and emitter of the transistor Q6, the base of the transistor Q7 is pulled low, the transistor Q7 is turned off, and the voltage output from the connection point RX2 is the voltage of the second power supply V2 (the voltage is a high signal for the second control unit 31), that is, the connection point RX2 outputs a high signal.

If the second connection point S2 obtains the voltage signal as 0 through the connection line with the first connection point S1, the base input voltage of the transistor Q6 is also 0V, and the transistor Q6 is turned off. The voltage division of the second power source V2 on the resistor R17 turns on the transistor Q7, the connection point RX2 is grounded after passing through the collector and emitter of the transistor Q7, and the connection point RX2 is forced to be pulled low, that is, the connection point RX2 outputs a low level signal.

In summary, when the first signal sent by the first control unit 21 to the connection point TX1 is a high-level signal, the voltage signal input to the first connection point S1 is the first power source V1, and then the connection point RX2 also outputs a high-level signal; when the first signal transmitted from the first control unit 21 to the connection point TX1 is a low level signal, the voltage signal input to the first connection point S1 is 0, and the connection point RX2 outputs a low level signal. That is, when the first control unit 21 transmits a high level signal, the second control unit 31 receives the high level signal; when the first control unit 21 sends a low level signal, the second control unit 31 receives the low level signal. Thus, the second control unit 31 is able to identify the data content transmitted by the first control unit 21 from the received signal.

Referring to fig. 5 again, when the control board 20 provides the input power for the operation board 30, the first control unit 21 outputs the first power 22 to be transmitted to the first connection point S1 through the first transmitting module 111.

Referring to fig. 6, in the above embodiment, when the control board 20 sends data to the operation board 30, and the first signal sent by the first control unit 21 to the connection point TX1 is a high-level signal, the first power V1 can be transmitted to the first connection point S1 to be input to the second circuit 12.

On the contrary, when the operation panel 30 transmits data to the control panel 20, the connection point TX1 needs to be turned off, that is, the first control unit 31 turns off the signal transmission with the connection point TX 1. At this time, the third power source V3 can keep the transistor Q1 turned on, and then the transistor Q2 is turned on, so that the first power source V1 can be transmitted to the first connection point S1 through the transistor Q2 to be input into the second circuit 12. Thereby ensuring a stable power input in the second circuit 12 to support its ability to send signals to the first circuit 11.

Then, the second connection point S2 acquires the first power source 22 through a connection line with the first connection point S1. Then, the voltage conversion module 123 obtains the first power 22 from the second connection point S2, and converts the first power 22 into a second power, where the second power can provide an operating voltage for the second receiving module 122 and the second sending module 121.

The voltage conversion module 123 includes a fifth diode and a voltage conversion chip.

Specifically, the circuit structure of the second circuit 12 shown in fig. 7 is still used as an example for description. The fifth diode corresponds to the diode D6, and the voltage conversion chip corresponds to the voltage conversion chip U1.

Optionally, the voltage conversion module 123 further includes a capacitor C5, a capacitor C6, a capacitor C7, and a capacitor C8. The voltage conversion chip U1 can be a voltage stabilization chip with the model of LM7805, and the output voltage of the voltage conversion chip U1 can be just 5v only by inputting a direct-current stabilized voltage supply to the input end of the chip.

Specifically, the anode of the diode D6 is connected to the second connection point S2, the cathode of the diode D6 is connected to one end of the capacitor C5, one end of the capacitor C6 and the input end of the voltage conversion chip U1, the other end of the capacitor C5, the other end of the capacitor C6 and the ground end of the voltage conversion chip U1 are all grounded, the output end of the voltage conversion chip U1 is connected to one end of the capacitor C7 and one end of the capacitor C8, the other ends of the capacitor C7 and the capacitor C8 are both grounded, and the output end of the voltage conversion chip U1 is connected to the second transmitting module 121 and the second receiving module 122, respectively.

That is, when the voltage inputted to the input terminal of the voltage conversion chip U1 is the first power supply V1 (the voltage of the first power supply V1 is greater than the voltage of the second power supply V2), the output terminal of the voltage conversion chip U1 outputs the second power supply V2, and the second power supply V2 is used to provide the power supply voltage for the second transmitting module 121 and the second receiving module 122.

Referring to fig. 5 again, when the operation panel 30 needs to send data to the control panel 20, the second control unit 31 outputs a voltage signal corresponding to the second signal after passing through the second sending module 121, and transmits the voltage signal to the second connection point S2.

The second sending module 121 includes a fourth switching tube, a fifth switching tube and a seventh resistor.

Specifically, the circuit structure of the second circuit 12 shown in fig. 7 is still used as an example for description. The fourth switch tube corresponds to the triode Q4, the fifth switch tube corresponds to the triode Q5, and the seventh resistor corresponds to the resistor R13. At this time, as can be seen from the above embodiments, the connection point TX1 is turned off, and the first power source V1 is input to the second circuit 12 through the first connection point and the second connection point.

The fourth switching tube and the fifth switching tube are similar to the first switching tube and the second switching tube in the shape selection and use processes, and are not described herein again.

Optionally, the second sending module 121 further includes a resistor R11 and a resistor R12.

Specifically, one end of the resistor R11 is connected to the connection point TX2, the connection point TX2 is configured to be connected to the second control unit 31, the other end of the resistor R11 is connected to a base of the transistor Q4, an emitter of the transistor Q4 is connected to the second power supply V2, a collector of the transistor Q4 is connected to one end of the resistor R12 and one end of the resistor R13, the other end of the resistor R13 is grounded, the other end of the resistor R12 is connected to a base of the switching tube Q5, an emitter of the switching tube Q5 is grounded, and a collector of the switching tube Q5 is connected to the second connection point S2.

When the second signal sent to the connection point TX2 by the second control unit 31 is a high level signal, there is almost no voltage difference between the base and the emitter of the transistor Q4, the transistor Q4 is turned off, the base of the switching tube Q5 is grounded through the resistor R12 and the resistor R13, and the switching tube Q5 is also turned off. At this time, the voltage of the second connection point S2 is the voltage of the first connection point, i.e. the voltage of the first power source V1.

When the second signal sent by the second control unit 31 to the connection point TX2 is a low-level signal, the voltage difference between the base and the emitter of the transistor Q4 makes the transistor Q4 conduct. The second power source V2 forms a loop with the resistor R13 through the transistor Q4, the base of the switching tube Q5 has an input voltage, the switching tube Q5 is turned on, and at this time, the ground is connected to the second connection point S2 through the switching tube Q5, so as to forcibly pull down the voltage at the second connection point S2.

In summary, when the second signal sent by the second control unit 31 to the connection point TX2 is a high-level signal, the voltage of the second connection point S2 and the voltage of the first connection point S1 are both the voltage of the first power source V1; when the second signal sent by the second control unit 31 to the connection point TX2 is a low-level signal, the voltage of the second connection point S2 and the voltage of the first connection point S1 are both lower than the voltage of the first power source V1.

Referring to fig. 5 again, the first connection point S1 obtains the voltage signal through the connection line with the second connection point S2. Then, the first receiving module 112 obtains a corresponding level signal according to the voltage signal, and transmits the level signal to the first control unit 21, and the first control unit 21 can identify the content sent by the second control unit 31 according to the level signal.

The first receiving module 112 includes a first zener diode, a third switching tube, and a sixth resistor. Specifically, a circuit configuration of the first circuit 11 shown in fig. 6 will be described as an example. The first zener diode corresponds to the first zener diode DW1, the third switching tube corresponds to the transistor Q3, and the sixth resistor corresponds to the resistor R7. The specific type and use process of the third switch tube are similar to those of the first switch tube and the second switch tube, and are not described again here.

Optionally, the first receiving module 112 further includes a capacitor C1, a capacitor C2, a capacitor C3, a resistor R8, a resistor R9, and a resistor R10.

Specifically, one end of a capacitor C1 is connected to the first connection point S1 and the cathode of the zener diode DW1, the other end of the capacitor C1 is grounded, the anode of the zener diode DW1 is connected to one end of a resistor R7, the other end of a resistor R7 is connected to one end of a resistor R8, one end of a capacitor C2 and the base of a transistor Q3, the other end of the resistor R8 is grounded to the other end of a capacitor C2 and the emitter of a switching tube Q3, the collector of the switching tube Q3 is connected to one end of a resistor R9 and one end of a resistor R10, the other end of the resistor R9 is connected to the third power source V3, the other end of the resistor R10 is connected to one end of a capacitor C3 and the connection point RX1, the connection point RX1 is used for connecting to the second control unit 31, and the other end of the capacitor C3 is grounded.

If the voltage of the first connection point S1 is the voltage of the first power source V1, the first power source V1 is connected to the base of the transistor Q3 through the voltage regulator DW1 and the resistor R7, so that the transistor Q3 is turned on. At this time, the connection point RX1 is connected to ground through the resistor R10, the collector and the emitter of the switching transistor Q3, the connection point RX1 is forced to be pulled low, and the connection point RX1 outputs a low level.

If the voltage at the first connection point S1 is pulled down to be lower than the first power source V1 and lower than the regulated voltage of the regulator DW1, which results in the input voltage at the base of the transistor Q3 being 0, the transistor Q3 is turned off. At this time, the connection point RX1 is connected to the third power supply V3 through the resistor R10 and the resistor R9, the connection point RX1 is pulled high, and the connection point RX1 outputs a high level.

In summary, when the second signal sent by the second control unit 31 to the connection point TX2 is a high-level signal, the output of the connection point RX1 is a low level; when the second signal transmitted from the second control unit 31 to the connection point TX2 is a low level signal, the connection point RX1 outputs a high level. That is, when the second control unit 31 transmits a high level signal, the first control unit 21 receives a low level signal; when the second control unit 31 sends a low level signal, the first control unit 21 receives a high level signal. The first control unit 21 is able to identify the data content sent by the second control unit 31 from the received signal.

Of course, in another embodiment, in order for the first control unit 21 to also receive a high level signal when the second control unit 31 sends a high level signal; and the first control unit 21 receives the low level signal when the second control unit 31 transmits the low level signal. An inverting circuit may be added after the connection point RX1, for example, a not gate is added to invert the signal output from the connection point RX 1.

It can be understood that, as described above, the first sending module 111 and the first receiving module 112 are both connected to the first connection point S1, the second sending module 121 and the second receiving module 122 are both connected to the second connection point S2, and the first connection point S1 and the second connection point S2 are connected only by a connection line.

Therefore, during the process that the first control unit 21 transmits the first signal through the connection point TX1 and the second control unit 31 receives the level signal through the connection point RX2, the connection point RX1 and the connection point TX2 receive the corresponding signals at the same time, which may cause an abnormality in the entire data transmission process. The RX1 and TX2 are turned off to ensure that only the signal transmitter transmits signals and only the corresponding signal receiver receives signals transmitted by the signal transmitter.

For the same reason, during the process that the second control unit 31 sends the second signal through the connection point TX2 and the first control unit 21 receives the level signal through the connection point RX1, the connection point RX2 and the connection point TX1 need to be closed. Wherein the connection point being closed means that the signal transmission process between the connection point and the control unit connected thereto is interrupted.

Optionally, the second circuit further comprises an eleventh resistor, a first diode and a second diode connected in series. Referring to fig. 7 again, the eleventh resistor corresponds to the resistor R20, the first diode corresponds to the diode D3, and the second diode corresponds to the diode D4.

Specifically, the cathode of the diode D3 is connected to one end of the resistor R20, the non-grounded terminal of the capacitor C4, the collector of the switching tube Q5, and the anode of the diode D6, the connection point between the anode of the diode D3 and the cathode of the diode D4 is connected to the second connection point S2, and the cathode of the diode D3, the cathode of the diode D4, and the other end of the resistor R20 are all grounded. By using the unidirectional conductivity of the diode, the second receiving module 122 can only receive the voltage signal of the second connection point S2 through the diode D3, and the second transmitting module 121 can only transmit the voltage signal to the second connection point S2 through the diode D4.

Through the above manner, the process of the control board 20 sending data to the operation board 30 is realized, the process of the operation board 30 sending data to the control board 20 is also realized, and meanwhile, the process of the control board 20 supplying power to the operation board 30 is also realized. I.e. a complete communication process between the control panel 20 and the operation panel 30 can be realized.

Also, when the distance between the control board 20 and the operation board 30 is long, the control board 20 transmits the first power V1 instead of the second power V2. The voltage transmitted between the control board 20 and the operation board 30 is higher than the voltage transmitted between the existing control board 20 and operation board 30 (typically, the second power source V2). Therefore, the normal work and communication of the operating panel 30 can be ensured to be supplied with enough voltage, and the reliability of the data transmission process is improved.

Moreover, only one connection line is required between the first connection point S1 and the second connection point S2, which can save cost, and no additional power supply is required, and no additional cost is required.

In another embodiment, a two-wire connection may be used between the first circuit 11 and the second circuit 12. Please refer to fig. 8 and fig. 9.

As shown in fig. 8, a third connection point S3, an inductor L1 and ground are added to the first circuit 11, wherein the third connection point S3 is connected to one end of the inductor L1, and the other end of the inductor L1 is grounded.

As shown in fig. 9, a fourth connection point S4, a diode D5 and a diode D6 are added to the second circuit 12, wherein the fourth connection point S4 is connected to the anode of the diode D5 and the cathode of the diode D6, the cathode of the diode D5 is connected to the cathode of the diode D3, and the anode of the diode D6 is connected to the anode of the diode D4.

The first connection point S1 can be connected to the second connection point S2 by a connection line, and the third connection point S3 is connected to the fourth connection point S4 by a connection line. In this case, the complete communication process between the control board 20 and the operation board 30 is realized through the first connection point S1 and the second connection point S2, and the specific implementation process is similar to the above embodiment, and is not described herein again.

The first connection point S1 may be connected to the fourth connection point S4 by a connection line, and the third connection point is connected to the second connection point S2 by a connection line. In this case, the complete communication process between the control board 20 and the operation board 30 is realized through the first connection point S1 and the fourth connection point S4, and the specific implementation process is similar to the above embodiment, and is not described herein again.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; within the idea of the invention, also technical features in the above embodiments or in different embodiments can be combined, steps can be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A communication circuit, wherein the communication circuit is configured to be connected to a first control unit on a control board, a first power supply, and a second control unit on an operation board, respectively, the communication circuit comprising:

a second circuit for connection with the second control unit;

2. The communication circuit of claim 1,

the first sending module comprises a first switch unit and a second switch unit;

3. The communication circuit of claim 2,

the first switch unit comprises a first switch tube, a first resistor and a second resistor;

4. The communication circuit of claim 2,

the second switch unit comprises a second switch tube, a third resistor, a fourth resistor and a fifth resistor;

5. The communication circuit of claim 1,

the first receiving module comprises a first voltage stabilizing diode, a third switching tube and a sixth resistor;

6. The communication circuit of claim 1,

the second sending module comprises a fourth switching tube, a fifth switching tube and a seventh resistor;

7. The communication circuit of claim 1,

the second receiving module comprises a first capacitor, a second voltage stabilizing diode, a tenth resistor, a sixth switching tube and a seventh switching tube;

8. The communication circuit of claim 1,

the voltage conversion module comprises a fifth diode and a voltage conversion chip;

9. The communication circuit according to any of claims 1-8,

the second circuit further comprises an eleventh resistor, and a first diode and a second diode which are connected in series;

10. A household appliance, characterized in that it comprises a control panel, an operating panel and a communication circuit according to any one of claims 1 to 9;