A low-power consumption relay control circuit based on PWM signal driving

Abstract

The utility model discloses a low -power consumption relay control circuit based on PWM signal drive, including relay module, relay coil module and relay drive module, relay module The relay coil module with relay drive module is electric connection in proper order, relay drive module is electrically connected with control module, control module can send high level PWM wave and low level PWM wave to relay drive module, relay drive module can be used for driving the intermittent energization of relay coil module, the relay coil module can be used for the relay module closes, through adopting PWM waveform as the control signal of relay coil module energization and power off, make relay coil module work in intermittent state to compare the mode that the relay coil module is powered on continuously, and the power consumption is reduced in unit time, and the heat output reduces, and the energy saving also reduces the cost.

Description

Technical Field

[0001] This invention belongs to the technical field of electronic circuits, specifically a low-power relay control circuit driven by PWM signals. Background Technology

[0002] With the development of society, relays are widely used in various products, such as fans, induction cookers, water heaters and so on. However, most relay driving circuits currently use a series circuit of switching transistor and relay coil, and then directly drive the relay by inputting high and low voltages to the control terminal of the switching transistor.

[0003] Such circuits have poor anti-interference capabilities, and the switching transistor is prone to accidental turn-on, leading to circuit abnormalities. In addition, due to the continuous conduction of the switching transistor for a long time, the heat generated by the relay coil will increase, which will affect the lifespan of the relay itself and related electronic components. Most importantly, such drive circuits have high power consumption, wasting electrical energy and increasing the cost of use, making them unsuitable for products with high energy efficiency requirements. Utility Model Content

[0004] The purpose of this invention is to provide a low-power relay control circuit based on PWM signal drive to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution:

[0006] A low-power relay control circuit based on PWM signal driving includes a relay module, a relay coil module, and a relay drive module. The relay module, the relay coil module, and the relay drive module are electrically connected in sequence. The relay drive module is electrically connected to a control module. The control module can send high-level PWM waves and low-level PWM waves to the relay drive module. The relay drive module can be used to drive the relay coil module to intermittently energize, and the relay coil module can be used to close the relay module.

[0007] In a further technical solution, the relay module includes a relay RL1, the relay coil module includes a switching transistor Q1 and a power supply VCC, the power supply VCC is electrically connected to the first pin of the relay RL1, the drain (D) of the switching transistor Q1 is electrically connected to the second pin of the relay RL1, the source (S) of the switching transistor Q1 is grounded, the gate (G) of the switching transistor Q1 is electrically connected to one end of the relay drive module, and the power supply VCC is electrically connected to the other end of the relay drive module.

[0008] In a further technical solution, the drain of the switching transistor Q1 is electrically connected to a diode D1, the anode of the diode D1 is electrically connected to the drain of the switching transistor Q1, and the anode of the diode D1 is electrically connected to the power supply VCC.

[0009] In a further technical solution, the gate of the switching transistor Q1 is electrically connected to resistors R1 and R2. One end of resistor R1 is electrically connected to the relay drive module, and the other end of resistor R2 is grounded.

[0010] In a further technical solution, the relay drive module includes a transistor Q2, a resistor R4, a resistor R5, and a transistor Q3. The emitter (e) of transistor Q2 is electrically connected to the power supply VCC. The collector (c) of transistor Q2 is electrically connected to the resistor R1. The base (b) of transistor Q2 is electrically connected to one end of the resistor R4. The emitter (e) of transistor Q3 is electrically connected to the power supply VCC. The base (b) of transistor Q3 is electrically connected to the control module. The collector (c) of transistor Q3, the other end of resistor R4, and one end of resistor R5 form an intermediate node. The other end of resistor R5 is grounded.

[0011] In a further technical solution, the collector of diode Q2 is electrically connected to resistor R3, and the other end of resistor R3 is electrically connected to resistor R1.

[0012] In a further technical solution, the resistor R1 is electrically connected to a capacitor C1, and the other end of the capacitor C1 is grounded.

[0013] In a further technical solution, diode D2 is electrically connected to the base of diode Q2, and the other end of diode D2 is electrically connected to the power supply VCC.

[0014] The beneficial effects of this utility model are:

[0015] This invention uses a PWM waveform as the control signal for energizing and de-energizing the relay coil module, allowing the relay coil module to operate in an intermittent state. Compared to continuously energizing the relay coil module, this reduces power consumption and heat generation per unit time, saving energy and reducing costs.

[0016] Other features and advantages of this invention will be described in detail in the following detailed description section. Attached Figure Description

[0017] Figure 1 : Flowchart of this utility model.

[0018] Figure 2 : Circuit diagram of this utility model. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0020] Please refer to Figure 1-2 ;

[0021] This invention relates to a low-power relay control circuit driven by a PWM signal. To address the problems of high power consumption and high heat generation in existing relay drive circuits, the circuit specifically includes a relay module, a relay coil module, and a relay drive module. These three modules are electrically connected sequentially. The relay drive module is electrically connected to a control module, which can send high-level and low-level PWM waves to the relay drive module. In this embodiment, the control module includes an MCU microcontroller. The MCU microcontroller transmits high-level and low-level PWM waves to the relay drive module, where a high-level and a low-level signal constitute one cycle. The relay drive module can be used to intermittently energize the relay coil module. When the MCU microcontroller transmits a high-level signal to the relay drive module, the relay drive module... The block can drive the relay coil module to be energized, at which time the relay coil module can be used to close the relay module; when the MCU microprocessor transmits a low-level signal to the relay drive module, the relay coil module is de-energized, at which time the relay module is in the state of changing from closed to closed, and the relay module needs a certain amount of time to change from closed to closed; in this embodiment, within one high-level and one low-level cycle of the PWM wave, the energization time of the relay coil module is greater than the de-energization time, so that the relay module is always in the closed state; this novel utility model uses the PWM waveform as the control signal for energizing and de-energizing the relay coil module, so that the relay coil module works in an intermittent state, thereby reducing power consumption and heat generation per unit time compared to continuously energizing the relay coil module, saving energy and reducing costs.

[0022] In this embodiment, the relay module includes a relay RL1, which is a conventionally used relay and can be selected as 5V, 12V, or 15V. The relay coil module includes a switching transistor Q1 and a power supply VCC. In this embodiment, the switching transistor Q1 can be a 2N7002. The power supply VCC is electrically connected to the first pin of the relay RL1, the drain (D) of the switching transistor Q1 is electrically connected to the second pin of the relay RL1, the source (S) of the switching transistor Q1 is grounded, the gate (G) of the switching transistor Q1 is electrically connected to one end of the relay driver module, and the power supply VCC is electrically connected to the other end of the relay driver module.

[0023] When the switching transistor Q1 of the relay coil module receives a high-level signal, the switching transistor Q1 turns on, and the circuit of the relay coil module is also turned on, and the relay RL1 is energized.

[0024] In this embodiment, diode D1 is electrically connected to the drain of switching transistor Q1. The anode of diode D1 is electrically connected to the drain of switching transistor Q1, and the anode of diode D1 is electrically connected to the power supply VCC. Diode D1 can be a 1N4148. The function of diode D1 is that when the current flowing through the coil disappears, the induced electromotive force generated by the coil is dissipated by doing work through the circuit formed by diode D1 and the coil, thereby protecting the safety of other components in the circuit.

[0025] In this embodiment, the gate (G) of the switching transistor Q1 is electrically connected to resistors R1 and R2. One end of resistor R1 is electrically connected to the relay drive module, and the other end of resistor R2 is grounded. Resistors R1 and R2 form a voltage divider circuit to prevent the gate voltage of the switching transistor Q1 from being too high, thereby damaging the switching transistor Q1.

[0026] In this embodiment, the relay driving module is used to turn on and off the switching transistor Q1 within a unit time, and the off time is less than the on time. Specifically, this embodiment discloses a circuit distribution of the relay driving module: including transistor Q2, resistor R4, resistor R5 and transistor Q3. The emitter of transistor Q2 is electrically connected to the power supply VCC, the collector of transistor Q2 is electrically connected to resistor R1, the base of transistor Q2 is electrically connected to one end of resistor R4, the emitter of transistor Q3 is electrically connected to the power supply VCC, the base of transistor Q3 is electrically connected to the control module, the collector of transistor Q3 forms an intermediate node with the other end of resistor R4 and one end of resistor R5, the other end of resistor R5 is grounded, the collector of diode Q2 is electrically connected to resistor R3, the other end of resistor R3 is electrically connected to resistor R1, resistor R1 is electrically connected to capacitor C1, the other end of capacitor C1 is grounded; capacitor C1 acts as a filter to prevent the peak voltage at the moment transistor Q2 is turned on from burning out the switching transistor Q1.

[0027] In this embodiment, diode D2 is electrically connected to the base of diode Q2, and the other end of diode D2 is electrically connected to the power supply VCC.

[0028] In summary, the working principle of this invention is as follows: When the base (b) of transistor Q3 receives a low-level PWM signal, transistor Q3 is cut off and does not conduct, thus causing the base of transistor Q2 to also be low-level, preventing Q2 from conducting. Consequently, the gate (G) of switching transistor Q1 has no voltage and does not conduct, and the relay does not engage. When transistor Q3 receives a high-level PWM signal, it conducts, and the power supply VCC discharges through the circuit of transistor Q3 and resistor R5. At this time, the base of transistor Q2 is high-level, causing Q2 to conduct. The power supply VCC then supplies a high-level signal to the gate of switching transistor Q1 through the circuit of transistor Q2, resistors R3, R1, and R2, causing Q1 to conduct and the relay to engage. Continuously inputting a PWM signal to transistor Q3 causes switching transistor Q1 to constantly switch between on and off states, thereby reducing the power consumption of switching transistor Q1 and the relay coil module per unit time. As long as the off-time is less than the relay's off-time, the relay will remain engaged.

[0029] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0030] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other implementations that can be understood by those skilled in the art.

Claims

1. A low-power relay control circuit based on PWM signal driving, characterized in that, It includes a relay module, a relay coil module, and a relay drive module. The relay module, the relay coil module, and the relay drive module are electrically connected in sequence. The relay drive module is electrically connected to a control module. The control module can send high-level PWM waves and low-level PWM waves to the relay drive module. The relay drive module can be used to drive the relay coil module to be intermittently energized, and the relay coil module can be used to close the relay module.

2. The low-power relay control circuit based on PWM signal driving according to claim 1, characterized in that, The relay module includes a relay RL1, and the relay coil module includes a switching transistor Q1 and a power supply VCC. The power supply VCC is electrically connected to the first pin of the relay RL1, the drain (D) of the switching transistor Q1 is electrically connected to the second pin of the relay RL1, the source (S) of the switching transistor Q1 is grounded, the gate (G) of the switching transistor Q1 is electrically connected to one end of the relay drive module, and the power supply VCC is electrically connected to the other end of the relay drive module.

3. The low-power relay control circuit based on PWM signal driving according to claim 2, characterized in that, The drain of the switching transistor Q1 is electrically connected to a diode D1, the anode of the diode D1 is electrically connected to the drain of the switching transistor Q1, and the anode of the diode D1 is electrically connected to the power supply VCC.

4. The low-power relay control circuit based on PWM signal driving according to claim 2, characterized in that, The gate of the switching transistor Q1 is electrically connected to resistors R1 and R2. One end of resistor R1 is electrically connected to the relay drive module, and the other end of resistor R2 is grounded.

5. A low-power relay control circuit based on PWM signal driving according to claim 2, characterized in that, The relay drive module includes transistor Q2, resistors R4 and R5, and transistor Q3. The emitter (e) of transistor Q2 is electrically connected to the power supply VCC. The collector (c) of transistor Q2 is electrically connected to resistor R1. The base (b) of transistor Q2 is electrically connected to one end of resistor R4. The emitter (e) of transistor Q3 is electrically connected to the power supply VCC. The base (b) of transistor Q3 is electrically connected to the control module. The collector (c) of transistor Q3, the other end of resistor R4, and one end of resistor R5 form an intermediate node. The other end of resistor R5 is grounded.

6. A low-power relay control circuit based on PWM signal driving according to claim 1, characterized in that, The collector of diode Q2 is electrically connected to resistor R3, and the other end of resistor R3 is electrically connected to resistor R1.

7. A low-power relay control circuit based on PWM signal driving according to claim 4, characterized in that, The resistor R1 is electrically connected to the capacitor C1, and the other end of the capacitor C1 is grounded.

8. A low-power relay control circuit based on PWM signal driving according to claim 5, characterized in that, The base of transistor Q2 is electrically connected to diode D2, and the other end of diode D2 is electrically connected to the power supply VCC.

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