Low-power-consumption relay driving circuit

Abstract

The utility model belongs to the technical field of relays, and discloses a low power consumption relay drive circuit, which comprises a power supply port 12VS and an MCU control port RLYAC-OUTL, a relay RLY1 comprises a pin 1, a pin 2, a pin 3 and a pin 4, the pin 3 is connected with a port INVVOUT, the pin 4 is connected with a port INV-L, and the pin 1 and the pin 2 correspond to a coil and are used for controlling opening and closing between the pin 3 and the pin 4. The low-power-consumption relay has the advantages that low power consumption can be achieved through the triodes, the resistors and the capacitors, the power consumption reduction effect on a product with a plurality of relays working together is obvious, the low-power-consumption relay has the advantages of being rapid in action, high in reliability, low in cost, flexible in application and the like, and low power consumption can be achieved by matching the capacitors according to different internal parameters of the relays.

Description

Technical Field

[0001] The utility model relates to the technical field of relays, and in particular to a low-power consumption relay driving circuit. Background Art

[0002] Electromagnetic relay is a widely used electrical control component. Electromagnetic relay is generally composed of iron core, coil, armature, contact spring, etc. When a certain voltage is applied to both ends of the coil, a certain current will flow through the coil, thus generating an electromagnetic effect. The armature will overcome the pulling force of the return spring under the action of electromagnetic force and be attracted to the iron core, thereby driving the moving contact of the armature and the static contact (normally open contact) to close. When the coil is powered off, the electromagnetic attraction disappears, and the armature will return to its original position under the reaction force of the spring, so that the moving contact and the original static contact (normally closed contact) are released, so that the purpose of closing and disconnecting in the circuit is achieved.

[0003] When the relay contacts are in action, the voltage applied to both ends of the relay coil needs to reach a specified voltage value, which is called the pull-in voltage. After the relay contacts are completed, the position of the contacts needs to be maintained. At this time, the minimum voltage that needs to be applied to both ends of the relay coil is called the maintenance voltage. In order to reduce the power consumption of the relay coil, the voltage applied to both ends of the coil can be reduced after the relay contacts are in action. In the prior art, the pull-in voltage and maintenance voltage of the electromagnetic relay are controlled to be constant, which results in a large energy consumption.

[0004] Therefore, it is necessary to provide a low-power relay driving circuit with fast action, high reliability, low cost, and flexible application. Low power consumption can be achieved by matching capacitors according to different internal parameters of the relay. Utility Model Content

[0005] The utility model discloses a low-power relay driving circuit, providing a low-power relay driving circuit with a simple structure and low cost, which can effectively solve the technical problems involved in the background technology.

[0006] To achieve the above purpose, the technical solution of the utility model is:

[0007] A low-power relay driving circuit includes a power port 12VS and an MCU control port RLY_AC-OUT_L, a relay RLY1 includes pins 1, 2, 3 and 4, wherein pin 3 is connected to port INV_VOUT, pin 4 is connected to port INV-L, pin 1 and pin 2 correspond to a coil and are used to control the opening and closing between pin 3 and pin 4;

[0008] The power port 12VS is connected to the collector of the transistor Q1 through the resistor R3, the base of the transistor Q1 is connected to one end of the resistor R1 and one end of the resistor R2, the other end of the resistor R1 is connected to the MCU control port RLY_AC-OUT_L, the other end of the resistor R2 is connected to the port AGND, the emitter of the transistor Q2 and the positive end of the Zener diode Z1, the base of the transistor Q2 is connected to the emitter of the transistor Q1, the collector of the transistor Q2 is connected to the negative end of the Zener diode Z1, one end of the resistor R5, one end of the resistor R6 and one end of the capacitor CE3, the other end of the resistor R5, the other end of the resistor R6 and the other end of the capacitor CE3 are connected to the pin 2 of the relay RLY1;

[0009] The power port 12VS is connected to the emitter of the transistor Q4 and the positive end of the diode D1, the negative end of the diode D1 is connected to the pin 1 of the relay RLY1 and one end of the capacitor CE2, the collector of the transistor Q4 is connected to the other end of the capacitor CE2 and one end of the resistor R11, the other end of the resistor R11 is connected to the port AGND, the base of the transistor Q4 is connected to one end of the resistor R8, the other end of the resistor R8 is connected to the drain of the MOS tube Q3 and one end of the resistor R7, the other end of the resistor R7 is connected to the power port 12VS, the gate of the MOS tube Q3 is connected to one end of the resistor R9 and one end of the resistor R10, the other end of the resistor R9 is connected to the MCU control port RLY_AC-OUT_L, and the other end of the resistor R10 is connected to the source of the MOS tube Q3 and the port AGND.

[0010] Specifically, the circuit includes a driving circuit, a voltage doubling circuit and a voltage dividing circuit. The driving circuit control terminal is connected to the microcontroller pin, and the power supply is provided by the driving voltage 12VS. Its collector is connected to the voltage dividing circuit, and the voltage dividing circuit is connected to the rear stage of the coil. The voltage doubling circuit is incorporated into the positive electrode of the driving voltage. The voltage doubling circuit control terminal is connected to the microcontroller pin, and the driving voltage 12VS is connected to the drain of the field effect tube and the base of the triode. It has fast action, high reliability, and flexible application. Low power consumption can be achieved by matching appropriate resistors according to different relay parameters.

[0011] As a preferred improvement of the present invention: a resistor R4 is provided between the resistor R3 and the collector of the transistor Q1.

[0012] As a preferred improvement of the present utility model: the models of the transistor Q1 and the transistor Q2 are MMBT4401, and the model of the transistor Q4 is MMBT4403.

[0013] As a preferred improvement of the present invention: the model of the MOS tube Q3 is 2N7002.

[0014] As a preferred improvement of the present utility model: the MCU control port RLY_AC-OUT_L is connected to a single chip microcomputer.

[0015] As a preferred improvement of the present invention: the capacitor CE2 is an electrolytic capacitor.

[0016] As a preferred improvement of the present invention: the power port 12VS is connected to a 12V power supply.

[0017] The beneficial effects of the utility model are as follows:

[0018] The utility model can achieve low power consumption by using transistors and resistors and capacitors, and has a significant effect of reducing power consumption in products where multiple relays work together. It has the advantages of rapid action, high reliability, low cost and flexible application, and low power consumption can be achieved by matching capacitors according to different internal parameters of relays. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0020] Figure 1 It is a schematic diagram of a low-power relay driving circuit of the utility model;

[0021] Figure 2 This is an enlarged schematic diagram of the utility model circuit Figure 1 ;

[0022] Figure 3 This is an enlarged schematic diagram of the utility model circuit Figure 2 . DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention will be described clearly and completely below in combination with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0025] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0026] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0028] See also Figure 1 As shown, the utility model provides a low-power relay driving circuit, including a power port 12VS and an MCU control port RLY_AC-OUT_L, a relay RLY1 includes pins 1, 2, 3 and 4, wherein pin 3 is connected to port INV_VOUT, pin 4 is connected to port INV-L, pin 1 and pin 2 correspond to a coil and are used to control the opening and closing between pin 3 and pin 4. The MCU control port RLY_AC-OUT_L is connected to a single-chip microcomputer, the model of which can be STM32F334R876, and the power port 12VS is connected to a 12V power supply.

[0029] See also Figure 2As shown, the power port 12VS is connected to the collector of the transistor Q1 through a resistor R3, the base of the transistor Q1 is connected to one end of the resistor R1 and one end of the resistor R2, the other end of the resistor R1 is connected to the MCU control port RLY_AC-OUT_L, the other end of the resistor R2 is connected to the port AGND, the emitter of the transistor Q2 and the positive end of the Zener diode Z1, the base of the transistor Q2 is connected to the emitter of the transistor Q1, the collector of the transistor Q2 is connected to the negative end of the Zener diode Z1, one end of the resistor R5, one end of the resistor R6 and one end of the capacitor CE3, the other end of the resistor R5, the other end of the resistor R6 and the other end of the capacitor CE3 are connected to the pin 2 of the relay RLY1, a resistor R4 is provided between the resistor R3 and the collector of the transistor Q1, and the models of the transistor Q1 and the transistor Q2 are MMBT4401.

[0030] Specifically, in the driving circuit, the control signal is connected to the base of the first NPN transistor through a current limiting resistor, and its high level is connected to the collector of the first NPN transistor through a current limiting resistor by the driving voltage 12VS, the emitter of the first NPN transistor is connected to the base of the second NPN transistor, the collector of the second NPN transistor is connected to one end of the voltage-dividing resistor of the voltage-dividing circuit, the emitter of the second NPN transistor is directly grounded, the base of the first NPN transistor and the emitter of the second NPN transistor are connected to a base current limiting resistor, and the collector of the second NPN transistor and the emitter of the second NPN transistor are connected to a voltage-stabilizing diode.

[0031] See also Figure 3 As shown, the power port 12VS is connected to the emitter of the transistor Q4 and the positive end of the diode D1, the negative end of the diode D1 is connected to the pin 1 of the relay RLY1 and one end of the capacitor CE2, the collector of the transistor Q4 is connected to the other end of the capacitor CE2 and one end of the resistor R11, the other end of the resistor R11 is connected to the port AGND, the base of the transistor Q4 is connected to one end of the resistor R8, the other end of the resistor R8 is connected to the drain of the MOS tube Q3 and one end of the resistor R7, the other end of the resistor R7 is connected to the power port 12VS, the gate of the MOS tube Q3 is connected to one end of the resistor R9 and one end of the resistor R10, the other end of the resistor R9 is connected to the MCU control port RLY_AC-OUT_L, and the other end of the resistor R10 is connected to the source of the MOS tube Q3 and the port AGND. The transistor Q4 model is MMBT4403, the MOS tube Q3 model is 2N7002, and the capacitor CE2 is an electrolytic capacitor.

[0032] Specifically, in the voltage divider circuit, the driving voltage 12VS is connected to the coil via a diode, and the first voltage divider resistor, the second voltage divider capacitor and a voltage stabilizing capacitor are connected to the rear stage of the coil. The voltage divider resistor and the internal resistance of the relay form a voltage divider. In the voltage doubler circuit, the control signal is connected to the gate of the N-channel field effect tube via a current limiting resistor, the driving voltage 12VS is connected to the drain of the field effect tube via a current limiting resistor, and is connected to the base of the PNP transistor via a current limiting resistor. The source of the field effect tube is grounded, and the gate of the field effect tube and the source of the field effect tube are connected to a discharge resistor, the cathode of the diode is connected to an electrolytic capacitor, and the electrolytic capacitor is connected in series with a resistor, one end of which is grounded, the emitter of the PNP transistor is connected to the driving voltage, and the collector of the NP transistor is connected to the negative electrode of the voltage doubler capacitor. It has fast action, high reliability, low cost, and flexible application. Low power consumption can be achieved by matching capacitors according to different internal parameters of the relay.

[0033] Embodiment 1

[0034] The circuit structure includes a driving circuit, a voltage doubling circuit and a voltage dividing circuit.

[0035] The driving circuit, the control signal RLY_AC-OUT_L is connected to the base of the first NPN transistor Q1 through the current limiting resistor R1, and its high level is connected to the collector of the first NPN transistor Q1 through the first current limiting resistor R3 and the second current limiting resistor R4 by the driving voltage 12VS, the emitter of the first NPN transistor Q1 is connected to the base of the second NPN transistor Q2, the collector of the second NPN transistor Q2 is connected to the voltage divider resistors R5 and R6 of the voltage divider circuit, the emitter of the second NPN transistor Q2 is directly grounded, the base of the first NPN transistor Q1 and the emitter of the second NPN transistor Q2 are connected to a base current limiting resistor R2, and the collector of the second NPN transistor Q2 and the emitter of the second NPN transistor Q2 are connected to a voltage regulator diode.

[0036] The voltage divider circuit, the driving voltage 12VS is connected to the coil through the diode, the coil is connected to the first voltage divider resistor R5, the second voltage divider resistor R6 and a voltage stabilizing capacitor CE3, and the voltage divider resistor and the relay internal resistance form a voltage divider. It should be further explained that the use of other components to achieve the above effects should belong to the inventive concept of the utility model and should belong to the protection scope of the utility model.

[0037] Voltage doubling circuit, control signal RLY_AC-OUT_L is connected to the gate of N-channel field effect transistor Q3 through current limiting resistor R9, driving voltage 12VS is connected to the drain of field effect transistor Q3 through current limiting resistor R7, and further connected to the base of PNP transistor Q4 through current limiting resistor R8, the source of field effect transistor Q3 is grounded, the gate and source of field effect transistor Q3 are connected with a discharge resistor R10, the cathode of diode is connected to electrolytic capacitor CE2, the electrolytic capacitor CE2 is connected with resistor R11 in series, one end of resistor R11 is grounded, the emitter of PNP transistor Q4 is connected to driving voltage, and the collector of NPN transistor Q4 is connected to the cathode of electrolytic capacitor CE2.

[0038] When the low-power relay driving circuit of the utility model is working, when the control signal RLY_AC-OUT_L is at a high level, the driving circuit at this time: the base of the NPN transistor Q1 is at a high level and Q1 is turned on. After being turned on, the emitter of Q1 (the base of Q2) is at a high level, and the Q2 conduction coil is grounded after passing through a voltage-dividing resistor. At this time, the voltage doubling circuit: the gate of the field effect transistor Q3 is at a high level, Q3 is turned on and its drain is at a low level, the base of the PNP transistor Q4 is at a low level and Q4 is turned on. At this time, the voltage applied to both ends of the diode is the driving voltage minus the diode voltage drop plus the charging voltage of the electrolytic capacitor CE2 (i.e., the driving voltage is 12VS), the relay action voltage is doubled and its action is faster, when the electrolytic capacitor is fully charged, the voltage difference between its two ends is 0, and the voltage applied to both ends of the diode is the driving voltage minus the diode voltage drop, which reduces the relay holding voltage, thereby reducing the steady-state power consumption of the relay. When the control signal RLY_AC-OUT_L is at a low level, NPN transistors Q1 and Q2 are not conducting, field effect transistor Q3 is not conducting, the base of PNP transistor Q4 is at a high level and is not conducting, and there is no loop between the coil and the ground. Low power consumption can be achieved by using transistors and resistors and capacitors. The power consumption reduction effect is obvious in products where multiple relays work together. It has the advantages of fast action, high reliability, low cost and flexible application.

[0039] Although the implementation scheme of the utility model has been disclosed as above, it is not limited to the applications listed in the specification and the implementation scheme. It can be fully applied to various fields suitable for the utility model. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the utility model is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A low power consumption relay driving circuit, characterized in that: It includes a power port 12VS and an MCU control port RLY_AC-OUT_L. The relay RLY1 includes pins 1, 2, 3 and 4, wherein pin 3 is connected to the port INV_VOUT, and pin 4 is connected to the port INV-L. Pins 1 and 2 correspond to a coil and are used to control the opening and closing between pins 3 and 4. The power port 12VS is connected to the collector of the transistor Q1 through the resistor R3, the base of the transistor Q1 is connected to one end of the resistor R1 and one end of the resistor R2, the other end of the resistor R1 is connected to the MCU control port RLY_AC-OUT_L, the other end of the resistor R2 is connected to the port AGND, the emitter of the transistor Q2 and the positive end of the Zener diode Z1, the base of the transistor Q2 is connected to the emitter of the transistor Q1, the collector of the transistor Q2 is connected to the negative end of the Zener diode Z1, one end of the resistor R5, one end of the resistor R6 and one end of the capacitor CE3, the other end of the resistor R5, the other end of the resistor R6 and the other end of the capacitor CE3 are connected to the pin 2 of the relay RLY1; The power port 12VS is connected to the emitter of the transistor Q4 and the positive end of the diode D1, the negative end of the diode D1 is connected to the pin 1 of the relay RLY1 and one end of the capacitor CE2, the collector of the transistor Q4 is connected to the other end of the capacitor CE2 and one end of the resistor R11, the other end of the resistor R11 is connected to the port AGND, the base of the transistor Q4 is connected to one end of the resistor R8, the other end of the resistor R8 is connected to the drain of the MOS tube Q3 and one end of the resistor R7, the other end of the resistor R7 is connected to the power port 12VS, the gate of the MOS tube Q3 is connected to one end of the resistor R9 and one end of the resistor R10, the other end of the resistor R9 is connected to the MCU control port RLY_AC-OUT_L, and the other end of the resistor R10 is connected to the source of the MOS tube Q3 and the port AGND.

2. A low power consumption relay driving circuit according to claim 1, characterized in that: A resistor R4 is provided between the resistor R3 and the collector of the transistor Q1.

3. A low power consumption relay driving circuit according to claim 1, characterized in that: The transistor Q1 and the transistor Q2 are of model MMBT4401, and the transistor Q4 is of model MMBT4403.

4. A low power consumption relay driving circuit according to claim 1, characterized in that: The model of the MOS tube Q3 is 2N7002.

5. A low power consumption relay driving circuit according to claim 1, characterized in that: The MCU control port RLY_AC-OUT_L is connected to the single chip microcomputer.

6. A low power consumption relay driving circuit according to claim 1, characterized in that: The capacitor CE2 is an electrolytic capacitor.

7. A low power consumption relay driving circuit according to claim 1, characterized in that: The power port 12VS is connected to a 12V power source.

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