CN212695929U - Rotating speed adjusting circuit and equipment - Google Patents
Rotating speed adjusting circuit and equipment Download PDFInfo
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- CN212695929U CN212695929U CN202021757106.3U CN202021757106U CN212695929U CN 212695929 U CN212695929 U CN 212695929U CN 202021757106 U CN202021757106 U CN 202021757106U CN 212695929 U CN212695929 U CN 212695929U
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Abstract
The utility model discloses a rotational speed adjusting circuit and equipment. The rotating speed adjusting circuit comprises a microcontroller, a feedback adjusting circuit and an output circuit; the microcontroller is connected with the input end of the feedback adjusting circuit, the output end of the feedback adjusting circuit is connected with the first end of the output circuit, the feedback end of the feedback adjusting circuit is connected with the second end of the output circuit, and the third end of the output circuit is connected with the load; the feedback adjusting circuit receives the PWM signal sent by the microcontroller, acquires a first voltage output by the output circuit through the feedback end, adjusts the first voltage according to the PWM signal, and acquires and outputs an adjusted voltage to the output circuit; the output circuit receives the adjustment voltage and outputs a second voltage to the load according to the adjustment voltage, so that the load adjusts the rotating speed according to the second voltage. The design of the feedback adjusting circuit and the output circuit realizes the stable adjustment of the load rotating speed, avoids the use of a special chip for speed regulation, and reduces the production cost of products.
Description
Technical Field
The utility model relates to an electron electrical technology field especially relates to a rotational speed adjusting circuit and equipment.
Background
The direct current motor and the fan are components of common equipment in the technical field of electronics and electricity, and the rotating speed of the direct current motor and the rotating speed of the fan are generally required to be adjusted in the using process of the direct current motor and the fan so as to adapt to different working states of the equipment.
At present, in order to realize stable adjustment of the rotating speed of the direct current motor and the fan, special chips are generally required to be used in the direct current motor and the fan, and the special chips are expensive, so that the production cost of products is increased.
SUMMERY OF THE UTILITY MODEL
The utility model discloses a main aim at provides a rotational speed adjustment circuit and equipment aims at solving among the prior art rotational speed adjustment and needs to use special chip to lead to the technical problem that product manufacturing cost is high.
In order to achieve the above object, the present invention provides a rotation speed adjusting circuit, the circuit includes:
the feedback regulator comprises a microcontroller, a feedback regulation circuit and an output circuit; the microcontroller is connected with the input end of the feedback adjusting circuit, the output end of the feedback adjusting circuit is connected with the first end of the output circuit, the feedback end of the feedback adjusting circuit is connected with the second end of the output circuit, and the third end of the output circuit is connected with a load; wherein the content of the first and second substances,
the feedback adjusting circuit is used for receiving the PWM signal sent by the microcontroller, acquiring a first voltage output by the output circuit through the feedback end, adjusting the first voltage according to the PWM signal, and acquiring and outputting an adjusted voltage to the output circuit;
the output circuit is used for receiving the adjusting voltage and outputting a second voltage to the load according to the adjusting voltage, so that the load adjusts the rotating speed according to the second voltage.
Preferably, the feedback adjusting circuit includes an adjusting unit and a feedback unit; the first end of the adjusting unit is connected with the microcontroller, the second end of the adjusting unit is connected with the first end of the output circuit, the third end of the adjusting unit is connected with the first end of the feedback unit, and the second end of the feedback unit is connected with the second end of the output circuit; wherein the content of the first and second substances,
the feedback unit is used for acquiring a first voltage output by the output circuit and sending the first voltage to the adjusting unit;
the adjusting unit is used for receiving the PWM signal and the first voltage, and adjusting the first voltage according to the PWM signal to obtain an adjusted voltage.
Preferably, the adjusting unit includes a first triode and a first resistor; the base electrode of the first triode is connected with the microcontroller, the collector electrode of the first triode is connected with the first end of the first resistor, and the emitter electrode of the first triode is connected with the first end of the feedback unit; the second end of the first resistor is connected with the first end of the output circuit.
Preferably, the feedback unit includes a second resistor and a third resistor; the first end of the second resistor is connected with the second end of the output circuit, and the second end of the second resistor is respectively connected with the emitter of the first triode and the first end of the third resistor; and the second end of the third resistor is grounded.
Preferably, the output circuit includes a second triode, a third triode, a fourth resistor, a first capacitor and a second capacitor; wherein the content of the first and second substances,
the base electrode of the second triode is connected with the second end of the first resistor, the emitting electrode of the second triode is connected with the first end of the fourth resistor, and the collecting electrode of the second triode is grounded;
the second end of the fourth resistor is connected with the base electrode of the third triode;
an emitter of the third triode is respectively connected with a power supply and the first end of the first capacitor, and a collector of the third triode is respectively connected with the second end of the second resistor, the first end of the second capacitor and the load;
the second end of the first capacitor and the second end of the second capacitor are both grounded.
Preferably, the rotating speed adjusting circuit further comprises a filter circuit, and the filter circuit is respectively connected with the input end of the feedback adjusting circuit and the microcontroller.
Preferably, the filter circuit includes a fifth resistor and a third capacitor; a first end of the fifth resistor is connected with the microcontroller, and a second end of the fifth resistor is respectively connected with an input end of the feedback adjusting circuit and a first end of the third capacitor; and the second end of the third capacitor is grounded.
Preferably, the microcontroller is further connected to a rotation speed detection pin of the load.
Preferably, the load is a dc motor or a fan.
The utility model discloses still provide a rotational speed adjusting equipment, rotational speed adjusting equipment includes as above rotational speed adjusting circuit.
The utility model arranges a microcontroller, a feedback adjusting circuit and an output circuit in the rotating speed adjusting circuit; the microcontroller is connected with the input end of the feedback adjusting circuit, the output end of the feedback adjusting circuit is connected with the first end of the output circuit, the feedback end of the feedback adjusting circuit is connected with the second end of the output circuit, and the third end of the output circuit is connected with the load; the feedback adjusting circuit receives the PWM signal sent by the microcontroller, acquires a first voltage output by the output circuit through the feedback end, adjusts the first voltage according to the PWM signal, and acquires and outputs an adjusted voltage to the output circuit; the output circuit receives the adjustment voltage and outputs a second voltage to the load according to the adjustment voltage, so that the load adjusts the rotating speed according to the second voltage. The design of the feedback adjusting circuit and the output circuit realizes the stable adjustment of the load rotating speed, avoids the use of a special chip for speed regulation, and reduces the production cost of products.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.
Fig. 1 is a functional block diagram of an embodiment of the present invention;
fig. 2 is a schematic diagram of an alternative configuration of the speed adjustment circuit of fig. 1.
The reference numbers illustrate:
| reference numerals | Name (R) | Reference numerals | Name (R) | |
| 100 | |
120 | |
|
| 200 | Output circuit | Q1～Q3 | First to |
|
| 300 | Load(s) | R1～R5 | First to |
|
| 400 | Filter circuit | C1～C3 | First to third capacitors | |
| MCU | Micro-controller | | Power supply | |
| 110 | Adjusting unit | GND | Ground |
The objects, features and advantages of the present invention will be further described with reference to the accompanying drawings.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
It should be noted that, if directional indications (such as upper, lower, left, right, front and rear … …) are involved in the embodiment of the present invention, the directional indications are only used to explain the relative position relationship between the components, the motion situation, etc. in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indications are changed accordingly.
In addition, if there is a description relating to "first", "second", etc. in the embodiments of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions in the embodiments may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should not be considered to exist, and is not within the protection scope of the present invention.
The utility model provides a rotational speed adjusting circuit.
Referring to fig. 1, in an embodiment, the circuit includes a microcontroller MCU, a feedback adjustment circuit 100, and an output circuit 200; the microcontroller MCU is connected with the input end of the feedback adjusting circuit 100, the output end of the feedback adjusting circuit 100 is connected with the first end of the output circuit 200, the feedback end of the feedback adjusting circuit 100 is connected with the second end of the output circuit 200, and the third end of the output circuit 200 is connected with the load 300; the feedback adjusting circuit 100 is configured to receive a PWM signal sent by the microcontroller MCU, and obtain the first voltage V output by the output circuit 200 through the feedback endfbAccording to the PWM signal, the first voltage VfbAdjusting to obtain and output an adjusted voltage to the output circuit 200; the output circuit 200 is configured to receive the adjustment voltage and output a second voltage V according to the adjustment voltageoutTo the load 300, so that the load 300 adjusts the rotation speed according to the second voltage.
It should be understood that the load 300 refers to a device requiring speed adjustment, such as a dc motor or a fan, and the present embodiment is not limited thereto.
It should be noted that, in this embodiment, through the design of the hardware circuit, the adjustment of the rotation speed of the load 300 is realized, a dedicated chip is not required, the product cost is reduced, and meanwhile, the feedback adjustment circuit 100 in this embodiment obtains the first voltage V from the output circuit 200fbFeedback regulation is performed such that the second voltage V output by the output circuit 200outMore stable, and further enables the load 300 to realize stable rotation speed adjustment.
Further, the rotation speed adjusting circuit further includes a filter circuit 400, and the filter circuit 400 is respectively connected to the input end of the feedback adjusting circuit 100 and the microcontroller MCU.
It can be understood that the filter circuit 400 can filter the PWM signal sent by the microcontroller MCU, so as to make the input signal of the feedback adjusting circuit 100 more accurate.
In the embodiment, the rotation speed adjusting circuit is provided with the microcontroller, the feedback adjusting circuit and the output circuit; the microcontroller is connected with the input end of the feedback adjusting circuit, the output end of the feedback adjusting circuit is connected with the first end of the output circuit, the feedback end of the feedback adjusting circuit is connected with the second end of the output circuit, and the third end of the output circuit is connected with the load; the feedback adjusting circuit receives the PWM signal sent by the microcontroller, acquires a first voltage output by the output circuit through the feedback end, adjusts the first voltage according to the PWM signal, and acquires and outputs an adjusted voltage to the output circuit; the output circuit receives the adjustment voltage and outputs a second voltage to the load according to the adjustment voltage, so that the load adjusts the rotating speed according to the second voltage. The design of the feedback adjusting circuit and the output circuit realizes the stable adjustment of the load rotating speed, avoids the use of a special chip for speed regulation, and reduces the production cost of products.
Referring to fig. 1 and fig. 2 together, fig. 2 is a schematic diagram of an alternative structure of the rotation speed adjustment circuit of fig. 1.
In this embodiment, the feedback adjusting circuit 100 includes an adjusting unit 110 and a feedback unit 120; a first end of the adjusting unit 110 is connected to the microcontroller MCU, a second end of the adjusting unit 110 is connected to a first end of the output circuit 200, a third end of the adjusting unit 110 is connected to a first end of the feedback unit 120, and a second end of the feedback unit 120 is connected to a second end of the output circuit 200; wherein the feedback unit 120 is configured to obtain the first voltage V output by the output circuit 200fbAnd transmitting the first voltage VfbTo the adjusting unit 110; the adjusting unit 110 is configured to receive the PWM signal and the first voltage VfbAnd according to the PWM signal, the first voltage V is adjustedfbAnd adjusting to obtain an adjusted voltage.
Specifically, the adjusting unit 110 includes a first transistor Q1 and a first resistor R1; the base of the first triode Q1 is connected with the microcontroller MCU, the collector of the first triode Q1 is connected with the first end of the first resistor R1, and the emitter of the first triode Q1 is connected with the first end of the feedback unit 120; a second terminal of the first resistor R1 is connected to a first terminal of the output circuit 200.
The feedback unit 120 includes a second resistor R2 and a third resistor R3; a first end of the second resistor R2 is connected to a second end of the output circuit 200, and a second end of the second resistor R2 is connected to an emitter of the first transistor Q1 and a first end of the third resistor R3, respectively; the second end of the third resistor R3 is grounded.
It should be appreciated that the first transistor Q1 is an NPN transistor when the collector-emitter voltage difference V of the first transistor Q1 isceWhen the voltage reaches 0.6V, the first triode Q1 is amplified and conducted, and is cut off otherwise.
It should be noted that the second resistor R2 and the third resistor R3 can apply the first voltage VfbThe voltage division sampling is performed, and a negative feedback is formed in the adjusting unit 110, so that the driving voltage and current can be increased when the load 300 is started, smooth start rotation is ensured, and the voltage is stably adjusted after the load 300 stably works.
Further, the output circuit 200 includes a second transistor Q2, a third transistor Q3, a fourth resistor R4, a first capacitor C1, and a second capacitor C2; the base of the second triode Q2 is connected with the second end of the first resistor R1, the emitter of the second triode Q2 is connected with the first end of the fourth resistor R4, and the collector of the second triode Q2 is grounded; a second end of the fourth resistor R4 is connected with the base of the third triode Q3; an emitter of the third transistor Q3 is respectively connected to a power source SYS _12V and a first end of the first capacitor C1, and a collector of the third transistor Q3 is respectively connected to a second end of the second resistor R2, a first end of the second capacitor C2, and the load 300; a second terminal of the first capacitor C1 and a second terminal of the second capacitor C2 are both grounded.
It should be understood that the second transistor Q2 and the third transistor Q3 are PNP transistors, the second transistor Q2 can implement level conversion and enhance driving capability, and the third transistor Q3 controls voltage output and directly drives the load 300.
It should be noted that the first capacitor C1 is used for filtering the input voltage, the second capacitor C2 is used for filtering the output voltage, and after the third transistor Q3 outputs the voltage, the voltage needs to be filtered by the second capacitor C2 into a straight dc voltage.
The specific parameters of the third transistor Q3, the first capacitor C1, and the second capacitor C2 may be selected according to the actual operating voltage and current of the load 300.
Further, the filter circuit 400 includes a fifth resistor R5 and a third capacitor C3; a first end of the fifth resistor R5 is connected to the microcontroller MCU, and a second end of the fifth resistor R5 is connected to the input end of the feedback adjustment circuit 100 and the first end of the third capacitor C3, respectively; the second terminal of the third capacitor C3 is grounded.
In a specific implementation, when the load 300 is a dc motor or a FAN with a rotation speed detection pin, the rotation speed detection pin FAN _ DET is connected to the microcontroller MCU, so that the current rotation speed of the dc motor or the FAN can be fed back to the microcontroller MCU, and the microcontroller MCU can timely obtain the operating state of the motor or the FAN and accurately control the rotation speed of the motor or the FAN.
The following description, with reference to fig. 1 to 2, illustrates the working principle of the present embodiment as follows:
when the signal FAN _ PWM output by the microcontroller MCU is a low level signal, the base of the first triode Q1 is at a low level, the first triode Q1 is not turned on, the second triode Q2 is also not turned on according to the characteristics of the PNP triode, and further the third triode Q3 is not turned on, and the output circuit 200 outputs no voltage to the load 300;
when the signal FAN _ PWM output by the microcontroller MCU is a high level signal, the base of the first transistor Q1 is at a high level, the first transistor Q1 is turned on, the second transistor Q2 is also turned on according to the characteristics of the PNP transistor, and the third transistor Q3 is turned on, so that the output voltage Vout of the output circuit 200 is VSYS_12v0.3V to load 300;
when the output of the microcontroller MCUWhen the signal FAN _ PWM is a PWM signal, the PWM signal is filtered by the RC filter circuit 400 composed of the fifth resistor R5 and the third capacitor C3, and then input to the base of the first transistor Q1, and when the voltage difference between the collector and emitter of the first transistor Q1 is VceWhen the voltage reaches 0.6V, the first transistor Q1 is amplified and conducted, and the second resistor R2 and the third resistor R3 output the first voltage V to the output circuit 200fbThe divided voltage sampling is performed, and negative feedback is formed in the adjustment unit 110. The base voltage of the second triode Q2 is VbR4/(R4+ R5) -0.3V, which is connected to the base of the second transistor Q2 through the first resistor R1, when the difference between the base and emitter voltages V of the second transistor Q2beWhen the voltage is greater than 0.7V, the second triode Q2 is conducted, the base of the third triode Q3 obtains low level through the fourth resistor R4 and the second triode Q2, the third triode Q3 outputs corresponding voltage, and the voltage is filtered by the second capacitor C2 to obtain stable direct current voltage (namely the second voltage V)out) The load 300 is based on the second voltage VoutAnd adjusting the rotating speed.
According to the embodiment, through the specific design of the feedback adjusting circuit and the output circuit, the stable adjustment of the rotating speed of the common direct current motor or the fan can be realized by using simple hardware devices, the design sensitivity of the product is improved, and the cost of the product is reduced.
The utility model also provides a rotational speed adjusting device, rotational speed adjusting device includes the rotational speed adjusting circuit as described above, the circuit structure of the rotational speed adjusting circuit of rotational speed adjusting device can refer to the above-mentioned embodiment, and no longer repeated here; it can be understood that, since the rotation speed adjusting apparatus of the present embodiment adopts the technical solution of the rotation speed adjusting circuit, the rotation speed adjusting apparatus has all the above beneficial effects.
The above is only the preferred embodiment of the present invention, and not the scope of the present invention, all the equivalent structures or equivalent flow changes made by the contents of the specification and the drawings or the direct or indirect application in other related technical fields are included in the patent protection scope of the present invention.
Claims (10)
1. A rotating speed adjusting circuit is characterized by comprising a microcontroller, a feedback adjusting circuit and an output circuit; the microcontroller is connected with the input end of the feedback adjusting circuit, the output end of the feedback adjusting circuit is connected with the first end of the output circuit, the feedback end of the feedback adjusting circuit is connected with the second end of the output circuit, and the third end of the output circuit is connected with a load; wherein the content of the first and second substances,
the feedback adjusting circuit is used for receiving the PWM signal sent by the microcontroller, acquiring a first voltage output by the output circuit through the feedback end, adjusting the first voltage according to the PWM signal, and acquiring and outputting an adjusted voltage to the output circuit;
the output circuit is used for receiving the adjusting voltage and outputting a second voltage to the load according to the adjusting voltage, so that the load adjusts the rotating speed according to the second voltage.
2. A speed adjustment circuit according to claim 1, wherein the feedback adjustment circuit comprises an adjustment unit and a feedback unit; the first end of the adjusting unit is connected with the microcontroller, the second end of the adjusting unit is connected with the first end of the output circuit, the third end of the adjusting unit is connected with the first end of the feedback unit, and the second end of the feedback unit is connected with the second end of the output circuit; wherein the content of the first and second substances,
the feedback unit is used for acquiring a first voltage output by the output circuit and sending the first voltage to the adjusting unit;
the adjusting unit is used for receiving the PWM signal and the first voltage, and adjusting the first voltage according to the PWM signal to obtain an adjusted voltage.
3. A speed adjustment circuit according to claim 2, wherein the adjustment unit comprises a first transistor and a first resistor; the base electrode of the first triode is connected with the microcontroller, the collector electrode of the first triode is connected with the first end of the first resistor, and the emitter electrode of the first triode is connected with the first end of the feedback unit; the second end of the first resistor is connected with the first end of the output circuit.
4. A speed adjustment circuit according to claim 3, wherein the feedback unit comprises a second resistor and a third resistor; the first end of the second resistor is connected with the second end of the output circuit, and the second end of the second resistor is respectively connected with the emitter of the first triode and the first end of the third resistor; and the second end of the third resistor is grounded.
5. A tachometer circuit according to claim 4, wherein the output circuit comprises a second transistor, a third transistor, a fourth resistor, a first capacitor and a second capacitor; wherein the content of the first and second substances,
the base electrode of the second triode is connected with the second end of the first resistor, the emitting electrode of the second triode is connected with the first end of the fourth resistor, and the collecting electrode of the second triode is grounded;
the second end of the fourth resistor is connected with the base electrode of the third triode;
an emitter of the third triode is respectively connected with a power supply and the first end of the first capacitor, and a collector of the third triode is respectively connected with the second end of the second resistor, the first end of the second capacitor and the load;
the second end of the first capacitor and the second end of the second capacitor are both grounded.
6. A speed regulation circuit as claimed in any one of claims 1 to 5 further comprising a filter circuit connected to the input of the feedback regulation circuit and the microcontroller respectively.
7. A speed adjustment circuit according to claim 6, wherein the filter circuit comprises a fifth resistor and a third capacitor; a first end of the fifth resistor is connected with the microcontroller, and a second end of the fifth resistor is respectively connected with an input end of the feedback adjusting circuit and a first end of the third capacitor; and the second end of the third capacitor is grounded.
8. A speed regulation circuit as claimed in claim 7 wherein the microcontroller is further connected to a speed detection pin of the load.
9. A speed regulation circuit as claimed in claim 8 wherein the load is a DC motor or a fan.
10. A rotation speed adjustment apparatus comprising the rotation speed adjustment circuit according to any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021757106.3U CN212695929U (en) | 2020-08-20 | 2020-08-20 | Rotating speed adjusting circuit and equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021757106.3U CN212695929U (en) | 2020-08-20 | 2020-08-20 | Rotating speed adjusting circuit and equipment |
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| Publication Number | Publication Date |
|---|---|
| CN212695929U true CN212695929U (en) | 2021-03-12 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202021757106.3U Active CN212695929U (en) | 2020-08-20 | 2020-08-20 | Rotating speed adjusting circuit and equipment |
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|---|---|
| CN (1) | CN212695929U (en) |
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- 2020-08-20 CN CN202021757106.3U patent/CN212695929U/en active Active
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