Water control machine power supply circuit with overvoltage protection

Abstract

The utility model discloses a water control machine power supply circuit with overvoltage protection, comprising a power supply circuit electrically connected with a water control machine, the power supply circuit comprises a power supply voltage VCC, the power supply voltage VCC is electrically connected with an overvoltage protection circuit, and the overvoltage protection circuit is electrically connected with the water control machine; the overvoltage protection circuit comprises a voltage detection protection circuit, a feedback circuit, an anti-reverse connection circuit and a control chip IC. According to the utility model, through the arrangement of the voltage detection protection circuit and the feedback circuit, power can be cut off in time when the voltage is too large, the overvoltage protection of the water control machine is achieved, and through the arrangement of the reverse connection prevention circuit, the power supply voltage VCC can be directly grounded and the power supply to the water control machine is stopped when the circuit is reversely connected, so that the water control machine is protected. And through overvoltage protection and reverse connection protection, the risk of damage to the water control machine in the use process can be effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of the power supply circuit of a water control machine, in particular to a power supply circuit of a water control machine with overvoltage protection. Background Technique

[0002] The water control machine mainly consists of three parts: an electronic control module, an IC card, and a signal sending base meter. The electronic control module is the core of the water control machine. It is responsible for controlling units such as sampling, charging, and displaying of the water control machine. At the same time, corresponding measures are taken in a timely manner for the operating state of the water control machine, and then important operating data is saved for future use and analysis. When the water control machine is working, it is powered through the power supply circuit.

[0003] In the existing power supply circuit of the water control machine, when the voltage is too high, it cannot be protected in a timely manner. In addition, when the power supply circuit is connected to the water control machine, if it is connected reversely, it cannot cut off the power supply in a timely manner, and there is a risk of damaging the water control machine due to excessive voltage or reverse circuit connection. Considering the above situation, we have proposed a power supply circuit of a water control machine with overvoltage protection. Content of the Utility Model

[0004] The purpose of the utility model is to solve the deficiencies existing in the prior art, and a power supply circuit of a water control machine with overvoltage protection is proposed.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A power supply circuit of a water control machine with overvoltage protection includes a power supply circuit electrically connected to the water control machine. The power supply circuit includes a supply voltage VCC, and the supply voltage VCC is electrically connected to an overvoltage protection circuit, and the overvoltage protection circuit is electrically connected to the water control machine.

[0007] The overvoltage protection circuit includes a voltage detection and protection circuit, a feedback circuit, an anti-reverse connection circuit, and a control chip IC.

[0008] The voltage detection and protection circuit includes a switching transistor M1. One end of a resistor R3 is electrically connected to pin 3 of the switching transistor M1. Pin 3 of the switching transistor M1 is also electrically connected to pin 10 of a control chip IC. A diode D1 is connected in parallel to pins 1 and 2 of the switching transistor M1. The negative electrode of the diode D1 and pin 1 of the switching transistor M1 are both electrically connected to a supply voltage VCC. One end of a resistor R4 and one end of a resistor R5 are also electrically connected to pin 2 of the switching transistor M1. The other ends of the resistor R4 and the resistor R5 are both electrically connected to a water control machine. The other end of the resistor R3 is electrically connected to one end of a capacitor C2. The other end of the capacitor C2 is grounded. One end of a transistor Q1 is also electrically connected to pin 1 of the switching transistor M1. One end of a resistor R2 is electrically connected to the base of the transistor Q1. The collector of the transistor Q1 is electrically connected to the other end of the resistor R3.

[0009] Preferably, the feedback circuit includes a diode ZD1. The positive electrode of the diode ZD1 is electrically connected to pin 9 of the control chip IC and grounded. The positive electrode of the diode ZD1 is also electrically connected to pin 2 of the control chip IC. One end of a capacitor C1 is electrically connected to the negative electrode of the diode ZD1. One end of a resistor R1 is electrically connected to the other end of the capacitor C1. The other end of the capacitor C1 is also electrically connected to the other end of the resistor R2. The other end of the resistor R1 is electrically connected to the supply voltage VCC.

[0010] Preferably, the reverse connection prevention circuit includes a resistor R6. One end of the resistor R6 is electrically connected to the supply voltage VCC. The other end of the resistor R6 is electrically connected to pin 3 of a switching transistor M2. A diode D2 is connected in parallel to pins 1 and 2 of the switching transistor M2. Pin 1 of the switching transistor M2 and the negative electrode of the diode D2 are both grounded. Pin 2 of the switching transistor M2 is electrically connected to the positive electrode of the diode ZD1 and grounded.

[0011] Preferably, the diode ZD1 is a Zener diode, which is used to send an overvoltage signal to the control chip IC when the input voltage exceeds a set value.

[0012] Preferably, the switching transistor M1 is used to monitor the input voltage and cut off the power supply to the water control machine.

[0013] Preferably, the resistor R1 is a voltage dividing resistor, which is used to adapt to the working range of the diode ZD1.

[0014] Preferably, the resistor R2 is a current limiting resistor, which is used to protect the diode ZD1 and prevent overcurrent.

[0015] Compared with the existing technology, the beneficial effects of the present utility model are:

[0016] Through the setting of the voltage detection protection circuit and the feedback circuit, the utility model can cut off the power supply in time when the voltage is too high, so as to achieve overvoltage protection for the water control machine. And through the setting of the anti-reverse connection circuit, when the circuit is connected reversely, the power supply voltage VCC can be directly grounded to stop the power supply to the water control machine, achieving the effect of anti-reverse connection protection for the water control machine. Through overvoltage protection and anti-reverse connection protection, the risk of damage to the water control machine during use can be effectively reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 FIG. is a connection block diagram of a power supply circuit for a water control machine with overvoltage protection proposed by the utility model;

[0018] Figure 2 FIG. is a circuit diagram of a power supply circuit for a water control machine with overvoltage protection proposed by the utility model;

[0019] Figure 3 FIG. is a circuit diagram of an anti-reverse connection circuit of a power supply circuit for a water control machine with overvoltage protection proposed by the utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments.

[0021] Refer to Figures 1-3 , a power supply circuit for a water control machine with overvoltage protection, including a power supply circuit electrically connected to the water control machine. The power supply circuit includes a power supply voltage VCC. The power supply voltage VCC is electrically connected to an overvoltage protection circuit, and the overvoltage protection circuit is electrically connected to the water control machine;

[0022] The overvoltage protection circuit includes a voltage detection protection circuit, a feedback circuit, an anti-reverse connection circuit and a control chip IC. The control chip IC is used to receive the signal of the feedback circuit and perform power-off protection on the water control machine through the voltage detection protection circuit;

[0023] The voltage detection and protection circuit includes a switching transistor M1. The switching transistor M1 is used to monitor the input voltage and cut off the power supply to the water control machine. One end of a resistor R3 is electrically connected to pin 3 of the switching transistor M1. Pin 3 of the switching transistor M1 is also electrically connected to pin 10 of the control chip IC. A diode D1 is connected in parallel to pins 1 and 2 of the switching transistor M1. The negative electrode of the diode D1 and pin 1 of the switching transistor M1 are both electrically connected to the supply voltage VCC. The other end of pin 2 of the switching transistor M1 is electrically connected to one end of a resistor R4 and one end of a resistor R5. The other ends of the resistor R4 and the resistor R5 are both electrically connected to the water control machine. The other end of the resistor R3 is electrically connected to one end of a capacitor C2. The other end of the capacitor C2 is grounded. The emitter of a transistor Q1 is electrically connected to pin 1 of the switching transistor M1. One end of a resistor R2 is electrically connected to the base of the transistor Q1. The collector of the transistor Q1 is electrically connected to the other end of the resistor R3;

[0024] The feedback circuit includes a diode ZD1. The positive electrode of the diode ZD1 is electrically connected to pin 9 of the control chip IC and grounded. The positive electrode of the diode ZD1 is also electrically connected to pin 2 of the control chip IC. The diode ZD1 is a Zener diode. When the input voltage exceeds the set value, it is used to send an overvoltage signal to the control chip IC. One end of a capacitor C1 is electrically connected to the negative electrode of the diode ZD1. The other end of the capacitor C1 is electrically connected to one end of a resistor R1. The other end of the capacitor C1 is also electrically connected to the other end of the resistor R2. The other end of the resistor R1 is electrically connected to the supply voltage VCC. The resistor R1 is a voltage-dividing resistor, which is used to adapt to the working range of the diode ZD1. The resistor R2 is a current-limiting resistor, which is used to protect the diode ZD1 from overcurrent;

[0025] The reverse connection prevention circuit includes a resistor R6. One end of the resistor R6 is electrically connected to the supply voltage VCC. The other end of the resistor R6 is electrically connected to pin 3 of a switching transistor M2. A diode D2 is connected in parallel to pins 1 and 2 of the switching transistor M2. Pin 1 of the switching transistor M2 and the negative electrode of the diode D2 are both grounded. Pin 2 of the switching transistor M2 is electrically connected to the positive electrode of the diode ZD1 and grounded;

[0026] Through the setting of the voltage detection and protection circuit and the feedback circuit, the present utility model can cut off the power in time when the voltage is too high, achieving overvoltage protection for the water control machine, and through the setting of the reverse connection prevention circuit, when the circuit is connected reversely, the supply voltage VCC can be directly grounded to stop supplying power to the water control machine, achieving the effect of reverse connection protection for the water control machine. Through overvoltage protection and reverse connection protection, the risk of damage to the water control machine during use can be effectively reduced.

[0027] Working principle: When in use, when the power supply voltage VCC is normal and not reversed, the power supply voltage VCC is grounded successively through the resistor R6, the switching transistor M2 and the diode D2, and the power supply voltage VCC can supply power normally. When the power supply voltage VCC is reversed, the voltage output by the reverse connection prevention circuit is the voltage of the power supply voltage VCC. At the same time, the power supply voltage VCC is directly grounded and cannot supply voltage to the subsequent water control machine, thus achieving the effect of automatically cutting off the power of the water control machine when the circuit is reversed;

[0028] When the power supply voltage VCC supplies power normally, the resistor R1 divides the power supply voltage VCC. At the same time, the power supply voltage VCC enters the switching transistor M1, and the switching transistor M1 monitors the voltage. When the voltage is within the normal threshold, the switching transistor M1 conducts, and the diode ZD1 does not conduct. At this time, the power supply voltage VCC supplies power to the resistor R4, the resistor R5 and the water control machine. When the voltage is too high, the switching transistor M1 does not conduct, and at the same time the diode ZD1 conducts. The diode ZD1 sends an overvoltage signal to the control chip IC. At the same time, the resistor R1 divides the voltage, and the resistor R2 limits the current, achieving the effect of protecting the diode ZD1. When the switching transistor M1 does not conduct, the control chip IC controls the switching transistor M1 to cut off the power supply to the water control machine, so that it cannot supply voltage to the resistor R4, the resistor R5 and the water control machine, thus achieving the effect of power-off protection for the water control machine when the voltage is too high, so that the water control machine will only work when the power supply voltage VCC is positive.

[0029] The above is only the preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution of the present invention and its inventive concept, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A power supply circuit for a water control machine with overvoltage protection, including a power supply circuit electrically connected to the water control machine. The power supply circuit includes a supply voltage VCC, and is characterized in that, The power supply voltage VCC is electrically connected to an overvoltage protection circuit, and the overvoltage protection circuit is electrically connected to the water control machine; The overvoltage protection circuit includes a voltage detection and protection circuit, a feedback circuit, an anti-reverse connection circuit, and a control chip IC; The voltage detection and protection circuit includes a switching transistor M1. One end of a resistor R3 is electrically connected to pin 3 of the switching transistor M1, and pin 3 of the switching transistor M1 is also electrically connected to pin 10 of the control chip IC. A diode D1 is connected in parallel between pin 1 and pin 2 of the switching transistor M1. The negative electrode of the diode D1 and pin 1 of the switching transistor M1 are both electrically connected to the power supply voltage VCC. One end of a resistor R4 and one end of a resistor R5 are also electrically connected to pin 2 of the switching transistor M1. The other ends of the resistor R4 and the resistor R5 are both electrically connected to the water control machine. The other end of the resistor R3 is electrically connected to one end of a capacitor C2, and the other end of the capacitor C2 is grounded. The emitter of a triode Q1 is also electrically connected to pin 1 of the switching transistor M1. One end of a resistor R2 is electrically connected to the base of the triode Q1, and the collector of the triode Q1 is electrically connected to the other end of the resistor R3.

2. The water control machine power supply circuit with overvoltage protection according to claim 1, characterized in that The feedback circuit includes a diode ZD1. The positive electrode of the diode ZD1 is electrically connected to pin 9 of the control chip IC and grounded. The positive electrode of the diode ZD1 is also electrically connected to pin 2 of the control chip IC. The negative electrode of the diode ZD1 is electrically connected to one end of a capacitor C1. The other end of the capacitor C1 is electrically connected to one end of a resistor R1, and the other end of the capacitor C1 is also electrically connected to the other end of the resistor R2. The other end of the resistor R1 is electrically connected to the power supply voltage VCC.

3. The water control machine power supply circuit with overvoltage protection according to claim 2, wherein, The anti-reverse connection circuit includes a resistor R6. One end of the resistor R6 is electrically connected to the power supply voltage VCC, and the other end of the resistor R6 is electrically connected to pin 3 of a switching transistor M2. A diode D2 is connected in parallel between pin 1 and pin 2 of the switching transistor M2. Pin 1 of the switching transistor M2 and the negative electrode of the diode D2 are both grounded. Pin 2 of the switching transistor M2 is electrically connected to the positive electrode of the diode ZD1 and grounded.

4. The water control machine power supply circuit with overvoltage protection according to claim 2, characterized in that The diode ZD1 is a Zener diode, which is used to send an overvoltage signal to the control chip IC when the input voltage exceeds the set value.

5. The power supply circuit of the water control machine with overvoltage protection according to claim 1, characterized in that, The switching transistor M1 is used to monitor the input voltage and cut off the power supply to the water control machine.

6. The power supply circuit of a water control machine with overvoltage protection according to claim 4, characterized in that, The resistor R1 is a voltage-dividing resistor, which is used to adapt to the working range of the diode ZD1.

7. The power supply circuit of a water control machine with overvoltage protection according to claim 1, characterized in that The resistor R2 is a current-limiting resistor, which is used to protect the diode ZD1 and prevent overcurrent.

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