CN210692437U

CN210692437U - Relay drive circuit

Info

Publication number: CN210692437U
Application number: CN201922278059.8U
Authority: CN
Inventors: 田中山; 赖少川; 杨昌群; 牛道东; 李育特; 张晨; 李永钧; 林元文; 蒋通明
Original assignee: Yangzhou Hengchun Electronic Co ltd; Sinopec Marketing South China Co
Current assignee: Yangzhou Hengchun Electronic Co ltd; China Petroleum and Chemical Corp; Sinopec Sales Co Ltd South China Branch; China Oil and Gas Pipeline Network Corp
Priority date: 2019-12-17
Filing date: 2019-12-17
Publication date: 2020-06-05
Anticipated expiration: 2029-12-17

Abstract

The utility model belongs to the technical field of electronic circuit, concretely relates to relay drive circuit. Including power input end VCC, signal input end PWM, power output end VOUT, resistance R1, resistance R2, inductance L1, diode D1, triode Q1 and electric capacity C1, power input end VCC is in proper order through resistance R1, inductance L1 and triode Q1 are connected to GND, inductance L1 and diode D1's positive pole are connected to triode Q1's second pole, triode Q1 third pole is connected GND, signal input end PWM is connected to triode Q1's first pole through resistance R2, power output end VOUT and electric capacity C1's first end are connected to diode D1 negative pole, the second end of electric capacity C1 is connected to GND. The method is used for solving the problem that the action of the relay at the output end brings impact to the input end instantly. Through a circuit formed between the input end and the output end, by utilizing the current holding and charging and discharging characteristics of the inductor and the capacitor, large voltage drop generated in the subsequent relay action moment is compensated, and the influence of fluctuation on the power supply input end is reduced.

Description

Relay drive circuit

Technical Field

The utility model belongs to the technical field of electronic circuit, concretely relates to relay drive circuit.

Background

In traditional relay drive circuit, the output power supply is normally that the VCC power with the input directly connects at the output, the relay can produce great current fluctuation in the twinkling of an eye at actuation and disconnection, can cause the instant of voltage to fall and fluctuate, when a plurality of relays move simultaneously, this kind of power disturbance will be more serious, and present electronic circuit's supply voltage is more and more low, 3.3V and 1.8V power supply system are used to the majority, the violent power fluctuation that the relay action brought can be to the MCU of feed end, integrated circuit brings unpredictable's risk, also can bring pressure to the power supply chip.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model lies in overcoming the not enough of prior art, provides a relay drive circuit for solve output relay actuation or disconnection and bring the problem of impact for the input in the twinkling of an eye.

The utility model provides an above-mentioned technical problem's technical scheme as follows: the utility model provides a relay drive circuit, includes power input end VCC, signal input end PWM, power output end VOUT, resistance R1, resistance R2, inductance L1, diode D1, triode Q1 and electric capacity C1, power input end VCC is connected to GND through resistance R1, inductance L1 and triode Q1 in proper order, triode Q1's second pole is connected inductance L1 with diode D1's positive pole, triode Q1 third pole is connected GND, signal input end PWM warp resistance R2 is connected to triode Q1's first pole, diode D1 negative pole is connected power output end VOUT with electric capacity C1's first end, electric capacity C1's second end is connected to GND.

Compared with the prior art, the technical scheme has the following beneficial effects:

the energy storage inductor L1 connected in series in the circuit and the energy storage capacitor C1 connected at the power output end VOUT utilize the current holding characteristic and the capacitor charging and discharging characteristic of the inductor to reduce the power supply fluctuation caused by the action moment of the relay at the power output end VOUT and reduce the influence of the fluctuation on the power supply at the input end.

Further, the capacitor C1 is a polar capacitor.

According to the technical scheme, the polar capacitor with large capacity is used as the energy storage capacitor, and meanwhile, the polar capacitors with different capacities can be selected according to the current value of the driving follow-up relay.

Further, a first end of the capacitor C1 is a positive electrode, and a second end thereof is a negative electrode.

According to the scheme, due to the unidirectional conduction characteristic of the diode D1, the capacitor C1 cannot discharge to the ground through the transistor Q1, and the voltage of the capacitor C1 can be kept stable.

Further, the transistor Q1 is a MOS transistor, and the first electrode is a gate, the second electrode is a source, and the third electrode is a drain.

Furthermore, the voltage divider circuit is connected between the power output terminal VOUT and GND in series and used for adjusting the voltage value output by the power output terminal VOUT.

Further, the voltage dividing circuit comprises a resistor R4 and a resistor R5 which are connected in series, and a sampling output end VCAP _ ADC is connected between the resistor R4 and the resistor R5.

According to the scheme, the voltage of the power output end VOUT is collected and sent into the single chip microcomputer through the voltage division circuit, the voltage value of the power output end is detected through the single chip microcomputer, whether the preset voltage value is reached or not is judged, and then the on-off of the signal input end PWM is controlled, so that the voltage value of the power output end can reach the preset voltage value.

The utility model has the advantages that:

by a circuit formed between the power input end VCC and the power output end VOUT, large voltage drop generated at the moment of action of a relay connected with the power output end VOUT at a subsequent stage is compensated by utilizing the current holding characteristic and the capacitance charging and discharging characteristic of an inductor, and the reliable action of the subsequent relay is ensured; meanwhile, the output voltage fluctuation caused by the action of a relay at the output end of the power supply can not influence the power supply voltage at the input end; in addition, at the moment of disconnection, the inductor L1 continues to charge the capacitor C1 at the output end through the diode D1, so that the voltage at the power output end is increased and is higher than that at the power input end, relative voltage isolation is formed, and the power input end and the power output end are ensured not to influence each other; meanwhile, a voltage division circuit connected in parallel at the power output end is connected to an AD detection port of an external single chip microcomputer through a sampling output end formed by voltage division resistors R4 and R5, whether the voltage boosting of the power output end reaches a preset value is detected through the single chip microcomputer, the on-off of a signal input end PWM is controlled, and then the voltage value of the power output end is controlled through the voltage division circuit, due to the one-way conduction characteristic of a diode D1, the capacitor C1 cannot discharge to the ground through Q1, and the voltage stability of the capacitor C1 can be kept.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the technical solutions in the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic diagram of a circuit connection according to an embodiment of the present invention;

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and therefore are only examples, and the protection scope of the present invention is not limited thereby.

It is to be noted that unless otherwise specified, technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which the present invention belongs.

In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience of description and simplicity of description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral parts; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

Examples

As shown in fig. 1, the utility model provides a relay drive circuit, including power input end VCC, signal input end PWM, power output end VOUT, resistance R1, resistance R2, inductance L1, diode D1, triode Q1 and electric capacity C1, power input end VCC is in proper order through resistance R1, inductance L1 and triode Q1 are connected to GND, inductance L and diode D1's positive pole is connected to triode Q1's second pole, triode Q1 third pole connection GND, signal input end PWM is connected to triode Q1's first pole through resistance R2, power output end VOUT and electric capacity C1's first end is connected to diode D1 negative pole, electric capacity C1's second end is connected to GND. The energy storage inductor L1 and the diode D1 are connected in series in the circuit, and the energy storage capacitor C1 is arranged at the output end, so that the power supply fluctuation caused by the action moment of the relay at the output end is reduced by utilizing the charging and discharging characteristics and the current holding characteristic of the inductor and the capacitor and the unidirectional conduction characteristic of the diode, and the influence of the fluctuation on the power supply at the input end is reduced.

In this embodiment, the capacitor C1 adopts a high-capacity capacitor with polarity as the energy storage capacitor, the positive electrode of the capacitor is a first end, the negative electrode of the capacitor is a second end, and the positive electrode of the capacitor is connected to the power output terminal VOUT and GND respectively, as shown in fig. 1, and meanwhile, the polarity capacitors with different capacities can be selected according to the current value for driving the subsequent relay; the diode ensures that the current of the power output end VOUT cannot influence the current of the power input end VCC by utilizing the characteristic of one-way conduction of the diode; the inductor L1 is charged when the power input end VCC is switched on, the inductor L1 discharges the capacitor C1 after the power input end VCC is switched off, the voltage of the voltage output end VOUT is ensured to be increased and higher than the voltage value of the power input end VCC, voltage isolation is formed, and meanwhile, the capacity of the inductor L1 can be inductors with different capacities according to the subsequent relay current value; triode Q1 adopts the MOS pipe as the switch tube, and wherein the first pole of MOS pipe is the grid, and the second pole is the source electrode, and the third pole is the drain electrode, through the signal input part PWM input control signal who connects at the grid, controls the break-make of MOS pipe source electrode and drain electrode, and the power input end VCC of this circuit can external not equidimension voltage input sources such as 5V, 3.3V or 1.8V.

In this embodiment, still include a bleeder circuit, bleeder circuit establishes ties between output VOUT and GND, bleeder circuit is used for adjusting the voltage value that power output VOUT exported, wherein, bleeder circuit includes resistance R4 and resistance R5 of establishing ties, be connected with sampling output VCAP _ ADC between resistance R4 and the resistance R5, the voltage acquisition of power output VOUT is sent into the singlechip through sampling output VCAP _ ADC among the bleeder circuit, it adopts output VCAP _ ADC to detect the voltage value of power output VOUT to detect through singlechip AD detection port connection, judge whether reach predetermined voltage value, and then the break-make of control signal input PWM, when the voltage of power output VOUT was to having reached the predetermined value, singlechip control signal input PWM breaks off, make the voltage value of power output VOUT reach predetermined voltage value.

The specific working principle is that based on the boost chopping principle, a signal input end PWM (pulse-width modulation) input signal controls the on and off of an MOS (metal oxide semiconductor) transistor Q1, and when an MOS transistor Q1 is in an on state, a power supply input end VCC charges an inductor L1 and simultaneously charges a capacitor C1; when the MOS transistor Q1 is in an off state, due to the current retention characteristic of the inductor L1, the current flowing through the inductor L1 does not suddenly change, and the circuit of the inductor Q1 is already disconnected, so that the energy stored in the inductor L1 can only be discharged to the capacitor C1 through the diode D1, that is, the inductor L1 starts to charge the capacitor C1, the voltage output by the power output terminal VOUT at two ends of the capacitor C1 continues to rise and is higher than the power input voltage VCC, so that the power input terminal VCC is isolated from the voltage of the power output terminal VOUT in voltage, and it is ensured that the voltage fluctuation at the moment when the subsequent relay is disconnected and closed does not affect the power input terminal VCC, and meanwhile, due to the unidirectional conduction characteristic of the diode D1, it is ensured that the current fluctuation. A sampling output end VCAP _ ADC in a voltage division circuit composed of R4 and R5 is input to an AD sampling end of an external single chip microcomputer, and when the fact that a power output end VOUT reaches a set value is detected, chopping signals of a signal input end PWM are stopped.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.

Claims

1. A relay drive circuit, characterized in that: including power input VCC, signal input PWM, power output VOUT, resistance R1, resistance R2, inductance L1, diode D1, triode Q1 and electric capacity C1, power input VCC is connected to GND through resistance R1, inductance L1 and triode Q1 in proper order, triode Q1's second pole is connected inductance L1 with diode D1's positive pole, triode Q1 third pole is connected GND, signal input PWM warp resistance R2 is connected to triode Q1's first pole, diode D1 negative pole is connected power output VOUT with electric capacity C1's first end, electric capacity C1's second end is connected to GND.

2. The relay drive circuit according to claim 1, wherein: the capacitor C1 is a polar capacitor.

3. The relay drive circuit according to claim 2, wherein: the first end of the capacitor C1 is a positive electrode, and the second end is a negative electrode.

4. The relay drive circuit according to claim 3, wherein: the triode Q1 is a MOS transistor, and the first electrode is a gate, the second electrode is a source, and the third electrode is a drain.

5. The relay drive circuit according to claim 4, wherein: the voltage-dividing circuit is connected between the power output end VOUT and GND in series and used for adjusting the voltage value output by the power output end VOUT.

6. The relay drive circuit according to claim 5, wherein: the voltage division circuit comprises a resistor R4 and a resistor R5 which are connected in series, and a sampling output end VCAP _ ADC is connected between the resistor R4 and the resistor R5.