Output protection circuit

Abstract

This invention provides an output protection circuit, including a power supply circuit, a control module, a signal transmission circuit, and an anti-misconnection circuit. The control module is connected to the output of the power supply circuit and outputs a level signal. The signal transmission circuit connects the control module and the remote controller, and is used to enable or disable the connection between the control module and the remote controller based on the level signal output by the control module, and to transmit the control signal sent by the remote controller to the control module. The anti-misconnection circuit is connected between the signal transmission circuit and the remote controller. When the output of the anti-misconnection circuit is connected to the remote controller, the anti-misconnection circuit is activated, and the signal transmission circuit can output power to the remote controller and establish a communication connection between the control module and the remote controller. When the output of the anti-misconnection circuit is connected to AC high voltage, the anti-misconnection circuit is deactivated. Compared with the prior art, the output protection circuit of this invention can protect the components in the circuit from damage when AC high voltage input is mistakenly connected to the output.

Description

Technical Field

[0001] This utility model relates to an output protection circuit, belonging to the field of power electronics technology. Background Technology

[0002] Wired remote controls are typically connected to the output of a control circuit, enabling communication between the remote and a central processing unit (CPU). Users can then send command signals to the CPU via the remote, which executes the commands. However, users may mistakenly connect AC mains power to the control circuit's output, potentially damaging components and causing losses.

[0003] In view of this, it is indeed necessary to improve the control output terminal in the existing circuit to solve the above problems. Utility Model Content

[0004] The purpose of this invention is to provide an output protection circuit to protect the components in the circuit when the output is mistakenly connected to a high-voltage AC input.

[0005] To achieve the above objectives, this utility model provides an output protection circuit, comprising:

[0006] The power supply circuit is connected to the mains power supply and outputs a constant voltage.

[0007] The control module is connected to the output terminal of the power supply circuit and outputs a level signal;

[0008] The signal transmission circuit connects the control module and the remote controller. It is used to enable or disable the control module and the remote controller based on the level signal output by the control module, and to transmit the control signal sent by the remote controller to the control module.

[0009] The circuit for preventing misconnection is connected between the signal transmission circuit and the remote controller;

[0010] When the output of the anti-misconnection circuit is connected to the remote controller, the anti-misconnection circuit is turned on, and the signal transmission circuit can output power to the remote controller and communicate with the control module; when the output of the anti-misconnection circuit is connected to AC high voltage, the anti-misconnection circuit is turned off.

[0011] Optionally, the power supply circuit includes a rectifier module connected to the mains power, a first constant voltage module connected to the output terminal of the rectifier module, and a second constant voltage module connected to the output terminal of the first constant voltage module. The rectifier module is used to convert the AC mains power into DC power, the first constant voltage module is used to output a first constant voltage, the second constant voltage module is used to output a second constant voltage, and the control module is connected to the output terminal of the second constant voltage module.

[0012] Optionally, the first constant voltage is greater than the second constant voltage.

[0013] Optionally, the signal transmission circuit includes a voltage divider module and a first switch connected to the voltage divider module. The voltage divider module is connected to the output terminal of the control module, and the first switch is connected to the output terminal of the first constant voltage module and the input terminal of the remote controller. The first switch is turned on or off according to the level signal output by the control module, so that the remote controller outputs a corresponding level signal.

[0014] Optionally, the voltage divider module includes a first resistor and a second resistor connected in series. The first switch is a MOSFET. The gate of the first switch is connected to the common terminal of the first resistor and the second resistor, and the source is grounded. The drain of the first switch is connected to the output terminal of the first constant voltage module and the input terminal of the remote controller.

[0015] Optionally, the signal transmission circuit also includes a data acquisition module and a second switch connected to the data acquisition module. One end of the data acquisition module is connected to the drain of the first switch, and the other end is grounded. The second switch is connected to the output of the second constant voltage module and the control module. The data acquisition module is configured to acquire the level signal output by the remote controller to turn the second switch on or off, so that the remote controller can send a control signal to the control module.

[0016] Optionally, the acquisition module includes a third resistor and a fourth resistor connected in series. One end of the third resistor is connected to the drain of the first switch, and one end of the fourth resistor is grounded. The second switch is a transistor, with its base connected between the third and fourth resistors, its collector connected to the output of the second constant voltage module and the control module, and its emitter grounded.

[0017] Optionally, the anti-misconnection circuit includes a diode module and a resettable fuse. When the output of the anti-misconnection circuit is connected to a remote controller, the diode module and the resettable fuse are turned on. When the output of the anti-misconnection circuit is connected to AC high voltage, the resettable fuse is turned off.

[0018] Optionally, the diode module includes a first diode and a second diode. The anode of the first diode is connected to the drain of the first switch, and the cathode is connected to the remote controller. The anode of the second diode is grounded, and the cathode is connected to the cathode of the first diode. One end of the resettable fuse is connected to the remote controller, and the other end is connected to the anode of the second diode.

[0019] Optionally, when the output of the anti-misconnection circuit is connected to AC high voltage, the first diode will not conduct in reverse; or, the second diode will conduct in forward to form a short circuit, causing the resettable fuse to trip.

[0020] The beneficial effects of this invention are as follows: The output protection circuit of this invention connects to the signal transmission circuit and the remote controller via an anti-misconnection circuit. When the output of the anti-misconnection circuit is connected to the remote controller, the anti-misconnection circuit conducts normally. At this time, the signal transmission circuit can output power to the remote controller and establish a communication connection between the control module and the remote controller. However, when the output of the anti-misconnection circuit is connected to AC high voltage, the anti-misconnection circuit is directly disconnected. Compared to existing technologies, the output protection circuit of this invention can protect the components in the circuit from damage when AC high voltage input is mistakenly connected to the output. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the output protection circuit of this utility model.

[0022] Figure 2 yes Figure 1 The circuit diagram of the output protection circuit shown is shown.

[0023] Figure label:

[0024] 100- Output protection circuit;

[0025] 1-Power supply circuit; 11-Rectifier module; 12-First constant voltage module; 13-Second constant voltage module; 2-Control module; 3-Remote controller; 4-Signal transmission circuit; 5-Anti-misconnection circuit; Q2-First switch; Q1-Second switch; R6-First resistor; R7-Second resistor; R2-Third resistor; R3-Fourth resistor; R4-Fifth resistor; R5-Sixth resistor; R1-Seventh resistor; FR-Resettable fuse; D1-First diode; D2-Second diode. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] Please see Figure 1 As shown, this utility model discloses an output protection circuit 100, including a power supply circuit 1 connected to mains power, a control module 2 connected to the output terminal of the power supply circuit 1, a signal transmission circuit 4 for connecting the control module 2 and a remote controller 3, and an anti-misconnection circuit 5 connected between the signal transmission circuit 4 and the remote controller 3. The anti-misconnection circuit 5 can conduct when its output terminal is connected to the remote controller 3 to ensure circuit continuity, and disconnect when its output terminal is mistakenly connected to AC high voltage to protect the components in the circuit from damage.

[0028] like Figure 2As shown, power supply circuit 1 outputs a constant voltage to power control module 2, remote controller 3, and other circuits. In this embodiment, power supply circuit 1 includes a rectifier module 11 connected to AC mains power, a first constant voltage module 12 connected to the output terminal of rectifier module 11, and a second constant voltage module 13 connected to the output terminal of the first constant voltage module 12. Rectifier module 11 converts AC mains power to DC mains power. The first constant voltage module 12 regulates the DC mains power to output a constant DC mains power, thus outputting a first constant voltage. The second constant voltage module 13 steps down the first constant voltage to output a second constant voltage. That is, the first constant voltage is greater than the second constant voltage. In this embodiment, the first constant voltage is 24V, and the second constant voltage is 5V. Control module 2 is connected to the output terminal of the second constant voltage module 13 to operate using the second constant voltage.

[0029] In this embodiment, the control module 2 outputs a level signal, preferably an MCU module, which outputs a high or low level. The signal transmission circuit 4 is used to connect or disconnect the control module 2 and the remote controller 3 based on the level signal output by the control module 2, and to transmit the control signal from the remote controller 3 to the control module 2. After receiving the control signal, the control module 2 processes the signal and executes the command. Taking the output protection circuit of this utility model applied to a bathroom heater as an example, the remote controller 3 is preferably a wired switch panel, and the user can operate the bathroom heater in the corresponding mode by operating the switch panel.

[0030] like Figure 2 As shown, specifically, the signal transmission circuit 4 includes a voltage divider module and a first switch Q2 connected to the voltage divider module. The voltage divider module is connected to the output terminal of the control module 2 and is used to divide the high voltage. The first switch Q2 is connected to the output terminal of the first constant voltage module 12 and the input terminal of the remote controller 3. The first switch Q2 is turned on or off according to the level signal output by the control module 2, so that the remote controller 3 outputs a corresponding level signal. Specifically, the voltage divider module includes a first resistor R6 and a second resistor R7 connected in series. The control module 2 has a transmitting terminal TX, and one end of the second resistor R7 is connected to the transmitting terminal TX. The first switch Q2 is a MOSFET. The gate of the first switch Q2 is connected to the common terminal node of the first resistor R6 and the second resistor R7, and the source is grounded. The drain of the first switch Q2 is connected to the output terminal of the first constant voltage module 12 and the input terminal of the remote controller 3. A fifth resistor R4 and a sixth resistor R5 are also provided between the output terminal of the first constant voltage module 12 and the drain of the first switch Q2 for dividing the first constant voltage.

[0031] Optionally, when control module 2 outputs a high level, the first resistor R6 and the second resistor R7 divide the high voltage to output a high level, turning on the first switch Q2. At this time, the first constant voltage is grounded after being divided by the fifth resistor R4 and the sixth resistor R5, and the voltage on the remote controller 3 is 0V, so the remote controller 3 outputs a low level. When control module 2 outputs a low level, the first resistor R6 and the second resistor R7 output a low level, and the first switch Q2 cannot be turned on. At this time, the first constant voltage is connected to the remote controller 3 after being divided by the fifth resistor R4 and the sixth resistor R5, and the voltage on the remote controller 3 is not 0V, so the remote controller 3 outputs a high level.

[0032] like Figure 2 As shown, the signal transmission circuit 4 further includes a data acquisition module and a second switch Q1 connected to the data acquisition module. One end of the data acquisition module is connected to the drain of the first switch Q2, and the other end is grounded. The second switch Q1 is connected to the output terminal of the second constant voltage module 13 and the control module 2. The data acquisition module is configured to acquire the high or low level output of the remote controller 3 to turn the second switch Q1 on or off, so that the remote controller 3 can send a control signal to the control module 2.

[0033] Specifically, the acquisition module includes a third resistor R2 and a fourth resistor R3 connected in series. One end of the third resistor R2 is connected to the drain of the first switch Q2, and one end of the fourth resistor R3 is grounded. The second switch Q1 is preferably an NPN transistor. The base of the second switch Q1 is connected between the third resistor R2 and the fourth resistor R3, the collector is connected to the output terminal of the second constant voltage module 13 and the control module 2, and the emitter is grounded. The control module also has a receiving terminal RX, and the collector of the second switch Q1 is connected to this receiving terminal RX. A seventh resistor R1 is also provided between the output terminal of the second constant voltage module 13 and the collector of the second switch Q1 for voltage division of the second constant voltage.

[0034] When the remote controller 3 outputs a low level, the voltage across the third resistor R2 and the fourth resistor R3 is 0V, and the second switch Q1 cannot conduct. At this time, there is no conductive connection between the remote controller 3 and the control module 2, and the remote controller 3 cannot send control signals to the control module 2. When the remote controller 3 outputs a high level, the voltage across the third resistor R2 and the fourth resistor R3 is not 0V. The third resistor R2 and the fourth resistor R3 output a high level, and the second switch Q1 conducts. At this time, the second constant voltage is grounded after being divided by the seventh resistor R1 and connected to the control module 2. A conductive connection is established between the remote controller 3 and the control module 2, and the remote controller 3 can send control signals to the control module 2.

[0035] In this embodiment, the signal transmission circuit 4 is preferably a two-wire controlled voltage carrier circuit. Its complete working process is as follows: When the control module 2 outputs a high level, the first resistor R6 and the second resistor R7 divide the high voltage and output a high level. The first switch Q2 is turned on. The first constant voltage is grounded after being divided by the fifth resistor R4 and the sixth resistor R5. The voltage received by the remote controller 3 is 0V. The third resistor R2 and the fourth resistor R3 collect the low level output by the remote controller 3. The second switch Q1 is not turned on. The second constant voltage is broken after being divided by the seventh resistor R1. The remote controller 3 and the control module 2 are not connected and cannot communicate.

[0036] When the control module 2 outputs a low level, the voltage across the first resistor R6 and the second resistor R7 is 0V. The first resistor R6 and the second resistor R7 output a low level, the first switch Q2 is not turned on, and the first constant voltage, after being divided by the fifth resistor R4 and the sixth resistor R5, is connected to the remote controller 3 and then grounded after passing through the third resistor R2 and the fourth resistor R3. The voltage on the remote controller 3 is not 0V, and the third resistor R2 and the fourth resistor R3 acquire the high level output from the remote controller 3. The second switch Q1 is turned on, and the second constant voltage, after being divided by the seventh resistor R1, is connected to the control module 2 and grounded. The remote controller 3 and the control module 2 are connected for communication.

[0037] In this embodiment, when the output terminal of the anti-misconnection circuit 5 is connected to the remote controller 3, the anti-misconnection circuit 5 is turned on, and the signal transmission circuit 4 can output power to the remote controller 3 and communicate with the control module 2 and the remote controller 3; when the output terminal of the anti-misconnection circuit 5 is connected to AC high voltage, the anti-misconnection circuit 5 is turned off.

[0038] like Figure 2 As shown, the anti-misconnection circuit 5 includes a diode module and a resettable fuse FR. When the output terminal of the anti-misconnection circuit 5 is connected to the remote controller 3, the diode module and the resettable fuse FR are conducting. When the output terminal of the anti-misconnection circuit 5 is connected to AC high voltage, the resettable fuse FR is disconnected. This utility model realizes the protection circuit when the output terminal is mistakenly connected to AC high voltage input, and the function of normal use after reconnecting to the remote controller.

[0039] The diode module includes a first diode D1 and a second diode D2. The anode of the first diode D1 is connected to the drain of the first switch Q2, and the cathode is connected to the remote control 3. The anode of the second diode D2 is grounded, and the cathode is connected to the cathode of the first diode D1. One end of the resettable fuse FR is connected to the remote control 3, and the other end is connected to the anode of the second diode D2. When the output of the anti-misconnection circuit 5 is connected to the remote control 3, the anti-misconnection circuit 5 is equivalent to a signal line connecting the signal transmission circuit 4 and the remote control 3.

[0040] When the output of the anti-misconnection circuit 5 is connected to AC high voltage, the first diode D1 will not conduct in reverse; or, the second diode D2 will conduct in forward direction, forming a short circuit, and the resettable fuse FR will trip. This prevents AC high voltage from entering the circuit and damaging the components. The resettable fuse FR can also automatically restore normal function after a remote control controller is connected to the output of the anti-misconnection circuit 5, ensuring that the circuit can continue to work normally.

[0041] In summary, the output protection circuit 100 of this utility model, by setting an anti-misconnection circuit 5 connected between the signal transmission circuit 4 and the remote controller 3, ensures that when the output of the anti-misconnection circuit 5 is connected to the remote controller 3, the anti-misconnection circuit 5 conducts normally, and the signal transmission circuit 4 can output power to the remote controller 3 and establish a communication connection between the control module 2 and the remote controller 3. When the output of the anti-misconnection circuit 5 is connected to AC high voltage, the anti-misconnection circuit 5 is directly disconnected. Compared with the prior art, the output protection circuit 100 of this utility model can protect the components in the circuit from damage when AC high voltage input is mistakenly connected to the output.

[0042] The above embodiments are only used to illustrate the technical solutions of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the spirit and scope of the technical solutions of this utility model.

Claims

1. An output protection circuit, characterized in that, include: The power supply circuit (1) is connected to the mains power and outputs a constant voltage; The control module (2) is connected to the output terminal of the power supply circuit (1) and outputs a level signal; The signal transmission circuit (4) connects the control module (2) and the remote controller (3), and is used to realize the connection or disconnection of the control module (2) and the remote controller (3) according to the level signal output by the control module (2), and transmit the control signal issued by the remote controller (3) to the control module (2); An anti-misconnection circuit (5) is connected between the signal transmission circuit (4) and the remote controller (3); When the output terminal of the anti-misconnection circuit (5) is connected to the remote controller (3), the anti-misconnection circuit (5) is turned on, and the signal transmission circuit (4) can output power to the remote controller (3) and communicate with the control module (2) and the remote controller (3); when the output terminal of the anti-misconnection circuit (5) is connected to AC high voltage, the anti-misconnection circuit (5) is turned off.

2. The output protection circuit according to claim 1, characterized in that: The power supply circuit (1) includes a rectifier module (11) connected to the mains power, a first constant voltage module (12) connected to the output terminal of the rectifier module (11), and a second constant voltage module (13) connected to the output terminal of the first constant voltage module (12). The rectifier module (11) is used to convert the AC mains power into DC power. The first constant voltage module (12) is used to output a first constant voltage. The second constant voltage module (13) is used to output a second constant voltage. The control module (2) is connected to the output terminal of the second constant voltage module (13).

3. The output protection circuit according to claim 2, characterized in that: The first constant voltage is greater than the second constant voltage.

4. The output protection circuit according to claim 2, characterized in that: The signal transmission circuit (4) includes a voltage divider module and a first switch (Q2) connected to the voltage divider module. The voltage divider module is connected to the output terminal of the control module (2). The first switch (Q2) is connected to the output terminal of the first constant voltage module (12) and the input terminal of the remote controller (3). The first switch (Q2) is turned on or off according to the level signal output by the control module (2) so that the remote controller (3) outputs a corresponding level signal.

5. The output protection circuit according to claim 4, characterized in that: The voltage divider module includes a first resistor (R6) and a second resistor (R7) connected in series. The first switch (Q2) is a MOS transistor. The gate of the first switch (Q2) is connected to the common terminal of the first resistor (R6) and the second resistor (R7), and the source is grounded. The drain of the first switch (Q2) is connected to the output terminal of the first constant voltage module (12) and the input terminal of the remote controller (3).

6. The output protection circuit according to claim 5, characterized in that: The signal transmission circuit (4) further includes a data acquisition module and a second switch (Q1) connected to the data acquisition module. One end of the data acquisition module is connected to the drain of the first switch (Q2), and the other end is grounded. The second switch (Q1) is connected to the output terminal of the second constant voltage module (13) and the control module (2). The data acquisition module is configured to acquire the level signal output by the remote controller (3) to turn the second switch (Q1) on or off, so that the remote controller (3) can send a control signal to the control module (2).

7. The output protection circuit according to claim 6, characterized in that: The acquisition module includes a third resistor (R2) and a fourth resistor (R3) connected in series. One end of the third resistor (R2) is connected to the drain of the first switch (Q2), and one end of the fourth resistor (R3) is grounded. The second switch (Q1) is a transistor. The base of the second switch (Q1) is connected between the third resistor (R2) and the fourth resistor (R3), the collector is connected to the output terminal of the second constant voltage module (13) and the control module (2), and the emitter is grounded.

8. The output protection circuit according to claim 5, characterized in that: The anti-misconnection circuit (5) includes a diode module and a resettable fuse. When the output terminal of the anti-misconnection circuit (5) is connected to the remote controller (3), the diode module and the resettable fuse are turned on. When the output terminal of the anti-misconnection circuit (5) is connected to AC high voltage, the resettable fuse is turned off.

9. The output protection circuit according to claim 8, characterized in that: The diode module includes a first diode (D1) and a second diode (D2). The anode of the first diode (D1) is connected to the drain of the first switch (Q2), and the cathode is connected to the remote controller (3). The anode of the second diode (D2) is grounded, and the cathode is connected to the cathode of the first diode (D1). One end of the resettable fuse is connected to the remote controller (3), and the other end is connected to the anode of the second diode (D2).

10. The output protection circuit according to claim 9, characterized in that: When the output terminal of the anti-misconnection circuit (5) is connected to AC high voltage, the first diode (D1) is reverse-biased and does not conduct; or, the second diode (D2) is forward-biased and forms a short circuit, and the resettable fuse is disconnected.

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