Relay drive control circuit and relay module

Abstract

A relay driving control circuit comprises a first switching device, a voltage dividing module and a short circuit module. The control end of the first switching device receives a relay control signal, the first end is grounded, and the second end is connected with the first end of the relay coil through the voltage dividing module; the first end of the short circuit module is connected with the first end of the relay coil and the first end of the voltage division module, the second end of the short circuit module is connected with the second end of the relay coil, and the third end of the short circuit module is connected with the second end of the voltage division module and the second end of the first switching device; and when the first switching device is switched on, the short circuit module is used for short-circuiting the voltage division module for a set time. According to the relay driving control circuit, the coil loss can be obviously reduced only by adopting few devices and a simple control process, so that the coil heating is reduced, and the normal control flow of the relay is hardly influenced.

Description

Technical Field

[0001] The utility model relates to the field of relay drive control, and more specifically, to a relay drive control circuit and a relay module. Background Art

[0002] In switching power supply products, a certain number of relays are usually required. The relay drive control circuit of the existing technology is as follows Figure 1 As shown in the figure, when the RELAY_CON signal is high, MOS transistor Q1 turns on, energizing the relay coil. However, as the power level and density of switching power supplies continue to increase, their size continues to shrink, leading to an increase in internal temperature rise. This is especially true for IP65-rated sealed products with liquid cooling, independent air ducts, and natural cooling. Effective heat dissipation from components like relays is particularly difficult. Consequently, relay coils generate significant heat. Reducing coil losses is the most direct and effective way to reduce coil heat. Currently, a common approach is to provide two power supplies, one for the relay's drive voltage and the other for its holding voltage, thereby reducing coil losses and thus coil heat. However, this approach not only requires numerous components to build the circuit but also complicates the control process. Utility Model Content

[0003] The technical problem to be solved by the present invention is to provide a relay drive control circuit and a relay module in response to the above-mentioned defects of the prior art, which can significantly reduce coil loss and thus reduce coil heating by adopting only a few components and a simple control process.

[0004] The technical solution adopted by the utility model to solve its technical problems is: constructing a relay drive control circuit, including: a first switching device, a voltage divider module and a short-circuit module; the control end of the first switching device receives a relay control signal, the first end is grounded, and the second end is connected to the first end of the relay coil via the voltage divider module; the first end of the short-circuit module is connected to the first end of the relay coil and the first end of the voltage divider module, the second end is connected to the second end of the relay coil, and the third end is connected to the second end of the voltage divider module and the second end of the first switching device; when the first switching device is turned on, the short-circuit module short-circuits the voltage divider module to set the time.

[0005] In the relay drive control circuit described in the present utility model, the short-circuit module includes a second switching device and a delayed on-off unit; the first end of the second switching device is connected to the second end of the first switching device and the first end of the delayed on-off unit, the control end of the second switching device is connected to the second end of the delayed on-off unit, the second end of the second switching device is connected to the first end of the relay coil, and the third end of the delayed on-off unit is connected to the second end of the relay coil; when the first switching device is turned on, the second switching device is turned on to short-circuit the voltage divider module, and the delayed on-off unit is used to control the on-off time of the second switching device.

[0006] In the relay drive control circuit described in the present utility model, the delayed on-off unit includes an RC charging unit, and the RC charging unit includes a charging resistor and a charging capacitor. The first end of the charging resistor is connected to the control end of the second switching device and the first end of the charging capacitor, the second end of the charging resistor is connected to the first end of the second switching device and the second end of the first switching device, and the second end of the charging capacitor is connected to the second end of the relay coil.

[0007] In the relay drive control circuit of the present invention, the voltage divider module includes at least one voltage divider resistor, and the first switch device and the second switch device include switch tubes.

[0008] Another technical solution adopted by the utility model to solve the technical problem is: constructing a relay drive control circuit, including: a first switch tube, a second switch tube, a voltage dividing resistor, a charging capacitor and a charging resistor;

[0009] The control end of the first switch tube receives the relay control signal, the first end is grounded, and the second end is connected to the first end of the relay coil via the voltage divider resistor;

[0010] The first end of the second switching tube is connected to the second end of the first switching tube and the first end of the charging resistor, the second end is connected to the first end of the relay coil, and the control end is connected to the second end of the charging resistor and the first end of the charging capacitor; the second end of the charging capacitor is connected to the second end of the relay coil.

[0011] In the relay drive control circuit described in the present invention, the first switch tube and the second switch tube are MOS tubes, the control ends of the first switch tube and the second switch tube are the gates of the MOS tubes, the first ends of the first switch tube and the second switch tube are the drains of the MOS tubes, and the second ends of the first switch tube and the second switch tube are the sources of the MOS tubes.

[0012] Another technical solution adopted by the present invention to solve the technical problem is: constructing a relay drive control circuit, which is composed of a first switch tube, a second switch tube, a voltage divider resistor, a charging capacitor and a charging resistor;

[0013] The control end of the first switch tube receives the relay control signal, the first end is grounded, and the second end is connected to the first end of the relay coil via the voltage divider resistor;

[0014] The first end of the second switching tube is connected to the second end of the first switching tube and the first end of the charging resistor, the second end is connected to the first end of the relay coil, and the control end is connected to the second end of the charging resistor and the first end of the charging capacitor; the second end of the charging capacitor is connected to the second end of the relay coil.

[0015] In the relay drive control circuit described in the present invention, the first switch tube and the second switch tube are MOS tubes, the control ends of the first switch tube and the second switch tube are the gates of the MOS tubes, the first ends of the first switch tube and the second switch tube are the drains of the MOS tubes, and the second ends of the first switch tube and the second switch tube are the sources of the MOS tubes.

[0016] Another technical solution adopted by the present invention to solve its technical problem is: constructing a relay module, including a relay and the aforementioned relay drive control circuit, the relay including the relay coil and the relay switch, and the first end of the relay coil is further connected to a power supply.

[0017] In the relay drive control circuit and relay module of the present invention, when the first switching device receives the relay control signal to control the relay to turn on, the short-circuit module short-circuits the voltage divider module for a period of time, so that the relay coil can be driven at a high level. After the relay drive is completed, the relay coil and the voltage divider module are connected in series, which can divide the voltage of the relay coil to reduce relay loss. Therefore, the relay drive control circuit only needs to use a few devices and a simple control process to significantly reduce coil loss, thereby reducing coil heating, which has almost no impact on the normal control process of the relay. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0019] Figure 1 It is a circuit diagram of a relay drive control circuit in the prior art;

[0020] Figure 2 This is a principle block diagram of a preferred embodiment of the relay drive control circuit of the present utility model;

[0021] Figure 3This is a principle block diagram of another preferred embodiment of the relay drive control circuit of the present utility model;

[0022] Figure 4 This is a circuit diagram of another preferred embodiment of the relay drive control circuit of the present utility model. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0024] Figure 2 This is a principle block diagram of a preferred embodiment of the relay drive control circuit of the present utility model. Figure 2 As shown, the relay drive control circuit of the present invention is suitable for driving and controlling the relay RELAY1, and includes: a first switch device Q1, a voltage dividing module 10 and a short circuit module 20. Figure 2 As shown, the control end of the first switching device Q1 receives the relay control signal RELAY_CON from the relay RELAY, the first end is connected to ground GND, and the second end is connected to the first end 1 of the relay coil via the voltage divider module 10. The short-circuit module 20 has a first end connected to the first end 1 of the relay coil and the first end of the voltage divider module 10, a second end connected to the second end of the relay coil 2, and a third end connected to the second end of the voltage divider module 10 and the second end of the first switching device Q1. The second end 2 of the relay coil is connected to the power supply VCC. When the first switching device Q1 is turned on, the short-circuit module 20 short-circuits the voltage divider module 10 for a set time.

[0025] In a preferred embodiment of the present invention, relay RELAY1 can be any relay known in the art. The first switching device Q1 can be any suitable switching device, such as an electrically controlled switch, a switching transistor, such as a MOS transistor, an IGBT transistor, etc. The voltage divider module 10 is preferably a voltage divider resistor. The short-circuit module 20 can be implemented using any suitable module, chip, or relay with a delay function. The short-circuit setting time of the voltage divider module is determined based on the time required for the relay switch to close. In this case, the setting time can be slightly longer than the relay switch closing time, for example, 15ms.

[0026] In the relay drive control circuit of the present invention, when the first switching device receives a relay control signal to control the relay to turn on, the short-circuit module short-circuits the voltage divider module for a period of time, so that the relay coil can be driven at a high level. After the relay drive is completed, the relay coil and the voltage divider module are connected in series, which can divide the voltage of the relay coil to reduce relay loss. Therefore, the relay drive control circuit only needs to use a few devices and a simple control process to significantly reduce coil loss, thereby reducing coil heating, and it has almost no impact on the normal control process of the relay.

[0027] Figure 3 This is a principle block diagram of another preferred embodiment of the relay drive control circuit of the present invention. Figure 2-3 As shown, the relay drive control circuit of the present invention is suitable for driving and controlling the relay RELAY1, and includes: a first switch device Q1, a voltage dividing module 10 and a short circuit module 20. Figure 3 As shown, the short-circuit module 20 includes a second switch device Q2 and a delayed on-off unit 21 , and the voltage dividing module includes a voltage dividing resistor R1 .

[0028] The control end of the first switching device Q1 receives the relay control signal RELAY_CON from the relay RELAY, a first end is connected to ground GND, and a second end is connected to the first end 1 of the relay coil via a voltage divider module 10. The first end of the second switching device Q2 is connected to the second end of the first switching device Q1 and the first end of the delay on / off unit 21. The control end of the second switching device Q2 is connected to the second end of the delay on / off unit 21. The second end of the second switching device Q2 is connected to the first end 1 of the relay coil. The third end of the delay on / off unit 21 is connected to the second end 2 of the relay coil, which is then connected to a power supply VCC. When the first switching device Q1 is turned on, the second switching device Q2 is turned on to short-circuit the voltage divider module 10. The delay on / off unit 21 is used to control the on / off time of the second switching device Q2.

[0029] In a preferred embodiment of the present invention, the relay RELAY can be any relay known in the art. The first switching device Q1 and the second switching device Q2 can be any suitable switching devices, such as an electronically controlled switch, a switching tube, such as a MOS tube, an IGBT tube, etc. The voltage divider module 10 is preferably a voltage divider resistor. The time-delay on-off unit 21 can be a delay chip or an RC charging unit. By setting the relevant parameters of the delay chip or the RC charging unit, the on-off time of the second switching device Q2 can be set. The on-off time can be determined according to the time required for the relay switch of the relay to be attracted, for example, it can be 15ms. For example, the RC charging unit includes a charging resistor and a charging capacitor. The first end of the charging resistor is connected to the control end of the second switching device Q2 and the first end of the charging capacitor. The second end of the charging resistor is connected to the first end of the second switching device Q2 and the second end of the first switching device Q1. The second end of the charging capacitor is connected to the second end of the relay coil.

[0030] In the relay drive control circuit of the present invention, when the first switching device receives a relay control signal to turn on the relay, the delayed on / off unit controls the second switching device to short-circuit the voltage divider module for a period of time, thereby driving the relay coil at a high level. After the relay is driven, the relay coil and the voltage divider module are connected in series, dividing the voltage of the relay coil to reduce relay losses. Therefore, the relay drive control circuit requires only a few components and a simple control process to significantly reduce coil losses, thereby reducing coil heating, with little impact on the normal control process of the relay. Furthermore, this embodiment uses common, simple circuits and components, resulting in very low cost and a very simple control process.

[0031] Figure 4 FIG. 1 is a circuit diagram of another preferred embodiment of the relay drive control circuit of the present invention. Figure 4 As shown, the relay drive control circuit of the present invention is suitable for driving and controlling the relay RELAY1, and includes: MOS transistor Q1, MOS transistor Q2, voltage divider resistor R1, charging capacitor C1 and charging resistor R2. Here, the MOS transistors Q1 and Q2 can also be replaced by other switching transistors. Figure 4 As shown, the gate of the MOS transistor Q1 receives the relay control signal RELAY_CON, the drain is grounded GND, and the source is connected to the first end 1 of the relay coil of the relay RELAY1 via the voltage divider resistor R1. The drain of the MOS transistor Q2 is connected to the source of the MOS transistor Q1 and the first end of the charging resistor R2, the source is connected to the first end 1 of the relay coil, and the gate is connected to the second end of the charging resistor R2 and the first end of the charging capacitor C1; the second end of the charging capacitor C1 is connected to the second end 2 of the relay coil.

[0032] In other preferred embodiments of the present invention, an IGBT or triode may be used in place of the MOS transistor. In a preferred embodiment of the present invention, the relay drive control circuit of the present invention comprises only: a MOS transistor Q1, a MOS transistor Q2, a voltage divider resistor R1, a charging capacitor C1, and a charging resistor R2. In other preferred embodiments of the present invention, the relay drive control circuit of the present invention may also include other functional components.

[0033] The following combination Figure 4 The principle of the relay drive control circuit of the present invention is described as follows. When the relay control signal RELAY_CON is high, MOS transistor Q1 turns on. At this time, due to the momentary short-circuit of charging capacitor C1, MOS transistor Q2 also turns on simultaneously, short-circuiting voltage-divider capacitor R1 and supplying VCC to the relay coil. As charging capacitor C1 charges, the voltage across charging resistor R2 decreases until it falls below the conduction threshold of MOS transistor Q2, at which point MOS transistor Q2 turns off. This period of time is the high-level drive time of the relay coil (i.e., the on-off time of MOS transistor Q2). This on-off time can be determined based on the time required for the relay switch to close. Those skilled in the art are aware that the time constant of an RC charging circuit is τ = RC, where R represents the capacitance of charging capacitor C1 and R represents the resistance of charging resistor R2. By designing and adjusting the parameters of charging capacitor C1 and charging resistor R2, the on-off time requirements can be met. The on-off time only needs to be slightly longer than the closing time of the relay switch; for example, it can be 15 ms. Those skilled in the art can select and design the circuit based on the aforementioned formula and actual product parameters. When MOS transistor Q2 is disconnected, the impedance of the relay coil is divided by voltage-divider resistor R1, reducing the voltage across the coil to the holding voltage, typically designed to be 0.75*VCC. Because voltage-divider resistor R1 participates in the voltage division, relay losses are significantly reduced. Therefore, this relay drive control circuit requires only a few simple components: a low-voltage MOS transistor, two resistors, and a capacitor. This achieves the loss-reducing effect of high-level driving and low-level maintenance, with minimal impact on the normal relay control process.

[0034] based on Figure 2-4 As can be seen from the illustrated embodiments, the present invention further discloses a relay module comprising a relay and any of the aforementioned relay drive control circuits. Based on the teachings of the present invention, those skilled in the art can construct the relay module and achieve the aforementioned beneficial effects, which will not be elaborated here.

[0035] Although the present invention is described through specific embodiments, those skilled in the art will appreciate that various modifications and equivalent substitutions may be made to the present invention without departing from the scope of the present invention. Furthermore, various modifications may be made to the present invention to address specific circumstances or materials without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed, but rather encompasses all embodiments falling within the scope of the claims of the present invention.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A relay drive control circuit, characterized in that: include: A first switching device, a voltage divider module and a short-circuit module; the control end of the first switching device receives a relay control signal, the first end is grounded, and the second end is connected to the first end of the relay coil via the voltage divider module; the first end of the short-circuit module is connected to the first end of the relay coil and the first end of the voltage divider module, the second end is connected to the second end of the relay coil, and the third end is connected to the second end of the voltage divider module and the second end of the first switching device; when the first switching device is turned on, the short-circuit module short-circuits the voltage divider module to set the time.

2. The relay drive control circuit according to claim 1, characterized in that: The short-circuit module includes a second switching device and a delayed on-off unit; the first end of the second switching device is connected to the second end of the first switching device and the first end of the delayed on-off unit, the control end of the second switching device is connected to the second end of the delayed on-off unit, the second end of the second switching device is connected to the first end of the relay coil, and the third end of the delayed on-off unit is connected to the second end of the relay coil; when the first switching device is turned on, the second switching device is turned on to short-circuit the voltage divider module, and the delayed on-off unit is used to control the on-off time of the second switching device.

3. The relay drive control circuit according to claim 2, characterized in that: The delayed on-off unit includes an RC charging unit, which includes a charging resistor and a charging capacitor. The first end of the charging resistor is connected to the control end of the second switching device and the first end of the charging capacitor. The second end of the charging resistor is connected to the first end of the second switching device and the second end of the first switching device. The second end of the charging capacitor is connected to the second end of the relay coil.

4. The relay drive control circuit according to claim 2, characterized in that: The voltage dividing module includes at least one voltage dividing resistor, and the first switching device and the second switching device include switching tubes.

5. A relay drive control circuit, characterized in that: include: A first switching tube, a second switching tube, a voltage divider resistor, a charging capacitor and a charging resistor; The control end of the first switch tube receives the relay control signal, the first end is grounded, and the second end is connected to the first end of the relay coil via the voltage divider resistor; The first end of the second switching tube is connected to the second end of the first switching tube and the first end of the charging resistor, the second end is connected to the first end of the relay coil, and the control end is connected to the second end of the charging resistor and the first end of the charging capacitor; the second end of the charging capacitor is connected to the second end of the relay coil.

6. The relay drive control circuit according to claim 5, characterized in that: The first switching tube and the second switching tube are MOS tubes, the control ends of the first switching tube and the second switching tube are gates of the MOS tubes, the first ends of the first switching tube and the second switching tube are drains of the MOS tubes, and the second ends of the first switching tube and the second switching tube are sources of the MOS tubes.

7. A relay drive control circuit, characterized in that: It consists of a first switching tube, a second switching tube, a voltage dividing resistor, a charging capacitor and a charging resistor; The control end of the first switch tube receives the relay control signal, the first end is grounded, and the second end is connected to the first end of the relay coil via the voltage divider resistor; The first end of the second switching tube is connected to the second end of the first switching tube and the first end of the charging resistor, the second end is connected to the first end of the relay coil, and the control end is connected to the second end of the charging resistor and the first end of the charging capacitor; the second end of the charging capacitor is connected to the second end of the relay coil.

8. The relay drive control circuit according to claim 7, characterized in that: The first switching tube and the second switching tube are MOS tubes, the control ends of the first switching tube and the second switching tube are gates of the MOS tubes, the first ends of the first switching tube and the second switching tube are drains of the MOS tubes, and the second ends of the first switching tube and the second switching tube are sources of the MOS tubes.

9. A relay module, characterized in that: It comprises a relay and the relay drive control circuit according to any one of claims 1 to 8, wherein the relay comprises the relay coil and a relay switch, and the first end of the relay coil is further connected to a power supply.

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