CN110792624A - Fan speed regulation circuit - Google Patents
Fan speed regulation circuit Download PDFInfo
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- CN110792624A CN110792624A CN201911318552.6A CN201911318552A CN110792624A CN 110792624 A CN110792624 A CN 110792624A CN 201911318552 A CN201911318552 A CN 201911318552A CN 110792624 A CN110792624 A CN 110792624A
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- 230000033228 biological regulation Effects 0.000 title claims abstract description 24
- 230000009467 reduction Effects 0.000 claims abstract description 64
- 238000001816 cooling Methods 0.000 claims abstract description 12
- 239000003990 capacitor Substances 0.000 claims description 81
- 230000001105 regulatory effect Effects 0.000 claims description 12
- 238000001914 filtration Methods 0.000 claims description 5
- 238000000034 method Methods 0.000 description 11
- 230000017525 heat dissipation Effects 0.000 description 9
- 230000008569 process Effects 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000003321 amplification Effects 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000010354 integration Effects 0.000 description 2
- 238000003199 nucleic acid amplification method Methods 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/004—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids by varying driving speed
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- Control Of Positive-Displacement Air Blowers (AREA)
- Cooling Or The Like Of Electrical Apparatus (AREA)
Abstract
The invention discloses a fan speed regulation circuit, which comprises: the temperature-reducing chip comprises a voltage-reducing chip, a temperature sensor, a first operational amplifier, a first resistor, a second resistor, a third resistor and a first diode, wherein the temperature sensor collects the temperature of a cooling object, the output end of the temperature sensor is connected with the reverse phase input end of the first operational amplifier, the voltage output end of the voltage-reducing chip is connected with the in-phase input end of the first operational amplifier, the third resistor is connected between the output end of the first operational amplifier and the negative electrode of the first diode, the positive electrode of the first diode is connected with the feedback end of the voltage-reducing chip, the first resistor is connected between the feedback end of the voltage-reducing chip and the ground, the second resistor is connected between the feedback end of the voltage-reducing chip and the voltage output end of the voltage-reducing chip, and the voltage. The voltage of the voltage output end of the voltage reduction chip is changed in order to maintain the voltage of the feedback end at a preset value by changing the voltage of the feedback end of the voltage reduction chip through temperature change.
Description
Technical Field
The invention relates to the field of electric appliance control, in particular to a fan speed regulation circuit.
Background
At present, a plurality of heating devices adopt an air cooling mode to dissipate heat. The most common and simple way is to supply power to the fan and let the fan work all the time, but the rotational speed of this kind of mode fan can't match with required heat dissipation capacity, leads to energy loss and produces the noise.
The problem can be solved by adjusting the rotating speed of the fan through the main control chip, but the rotating speed of the fan is controlled by the main control chip to occupy the resource of the main control chip, which may cause the situation that the resource of the main control chip is insufficient.
Disclosure of Invention
In view of this, the present invention provides a fan speed control circuit. The fan speed regulating circuit directly regulates the rotating speed of the fan through the temperature without passing through a main control chip, so that closed-loop control of the temperature and heat dissipation is formed, and resources of the main control chip are saved.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention discloses a fan speed regulating circuit, which comprises: a voltage reduction chip U1, a temperature sensor U2, a first operational amplifier U3, a first resistor R1, a second resistor R2, a third resistor R3 and a first diode D1,
the temperature sensor U2 collects the temperature of a cooling object, the output end of the temperature sensor U2 is connected with the inverting input end of the first operational amplifier U3, the voltage output end 1 of the voltage reduction chip U1 is connected with the non-inverting input end of the first operational amplifier U3, the output end of the first operational amplifier U3 is connected with one end of the third resistor R3, the other end of the third resistor R3 is connected with the negative electrode of the first diode D1, the positive electrode of the first diode D1 is connected with the feedback end 6 of the voltage reduction chip U1, the feedback end 6 of the voltage reduction chip U1 is connected with one end of the first resistor R1, the other end of the first resistor R1 is grounded, the feedback end 6 of the voltage reduction chip U1 is connected with one end of the second resistor R2, the other end of the second resistor R2 is connected with the voltage output end 1 of the voltage reduction chip U1, the voltage output end 1 of the voltage reduction chip U1 is connected with a power input end of a fan to provide power for the fan, wherein the voltage reduction chip U1 maintains the voltage of the feedback end 6 at a preset voltage value by adjusting the voltage of the voltage output end 1.
Optionally, the fan speed control circuit further includes: a second operational amplifier U4 for the second,
the output end of the temperature sensor U2 is connected with the non-inverting input end of the second operational amplifier U4, the inverting input end of the second operational amplifier U4 is grounded, and the output end of the second operational amplifier U4 is connected with the inverting input end of the first operational amplifier U3.
Optionally, the fan speed control circuit further includes: the inductance L is provided with a plurality of inductors,
one end of the inductor L is connected with the voltage output end 1 of the voltage reduction chip U1, and the other end of the inductor L is connected with the non-inverting input end of the first operational amplifier U3.
Optionally, the fan speed control circuit further includes: the second diode D2 is provided in the second,
the anode of the second diode D2 is grounded, and the cathode of the second diode D2 is connected to the voltage output terminal 1 of the buck chip U1.
Optionally, the fan speed control circuit further includes: a first capacitor C1, a second capacitor C2, a third capacitor C3 and a fourth capacitor C4,
one end of the first capacitor C1 is connected with the voltage input end 2 of the buck chip U1, and the other end of the first capacitor C1 is grounded;
one end of the second capacitor C2 is connected with the voltage input end 2 of the buck chip U1, and the other end of the second capacitor C2 is grounded;
one end of the third capacitor C3 is connected to the voltage output terminal 1 of the buck chip U1, and the other end of the third capacitor C3 is grounded;
one end of the fourth capacitor C4 is connected to the voltage output terminal 1 of the buck chip U1, and the other end of the fourth capacitor C4 is grounded;
the first capacitor C1, the second capacitor C2, the third capacitor C3 and the fourth capacitor C4 are used as filtering capacitors in the fan speed regulating circuit.
Optionally, the fan speed control circuit further includes: the fifth capacitance C5 is provided,
the fifth capacitor C5 is connected between the voltage output terminal 1 of the buck chip U1 and the boost capacitor terminal 3 of the buck chip U1, and serves as an energy-taking capacitor.
Optionally, the fan speed control circuit further includes: a sixth capacitor C6 and a fourth resistor R4,
one end of the sixth capacitor C6 is connected to the inverting input terminal of the first operational amplifier U3, the other end of the sixth capacitor C6 is connected to one end of the fourth resistor R4, and the other end of the fourth resistor R4 is connected to the output terminal of the first operational amplifier U3;
the sixth capacitor C6, the fourth resistor R4 and the operational amplifier form an integral circuit.
Optionally, the fan speed control circuit further includes: a fifth resistor R5 and a sixth resistor R6,
a voltage output end 1 of the buck chip U1 is connected to a non-inverting input end of the first operational amplifier U3, specifically, the voltage output end 1 of the buck chip U1 is connected to the fifth resistor R5, and the fifth resistor R5 is connected to a non-inverting input end of the first operational amplifier U3;
one end of the sixth resistor R6 is connected with the non-inverting input end of the first operational amplifier U3, and the other end of the sixth resistor R6 is grounded;
the fifth resistor R5 and the sixth resistor R6 are used as balance resistors in the fan speed regulating circuit.
Optionally, the fan speed control circuit further includes: a seventh resistor R7, an eighth resistor R8, a ninth resistor R9 and a tenth resistor R10,
one end of the seventh resistor R7 is connected with the inverting input end of the first operational amplifier U3, and the other end of the seventh resistor R7 is connected with the output end of the second operational amplifier U4;
one end of the eighth resistor R8 is connected with the output end of the second operational amplifier U4, and the other end of the eighth resistor R8 is connected with the inverting input end of the second operational amplifier U4;
one end of the ninth resistor R9 is connected with the inverting input end of the second operational amplifier U4, and the other end of the ninth resistor R9 is grounded;
one end of the tenth resistor R10 is connected with the output end of the temperature sensor U2, and the other end of the tenth resistor R10 is connected with the non-inverting input end of the second operational amplifier U4;
the seventh resistor R7, the eighth resistor R8, the ninth resistor R9 and the tenth resistor R10 are used as balance resistors in the fan speed regulating circuit.
Optionally, the voltage output by the temperature sensor U2 increases with an increase in the collected temperature.
The invention discloses a fan speed regulation circuit, which comprises: a voltage reduction chip U1, a temperature sensor U2, a first operational amplifier U3, a first resistor R1, a second resistor R2, a third resistor R3 and a first diode D1, wherein the temperature sensor U2 collects the temperature of a temperature reduction object, the output end of the temperature sensor U2 is connected with the inverting input end of the first operational amplifier U3, the voltage output end 1 of the voltage reduction chip U1 is connected with the non-inverting input end of the first operational amplifier U3, the output end of the first operational amplifier U3 is connected with one end of the third resistor R3, the other end of the third resistor R3 is connected with the negative electrode of the first diode D1, the positive electrode of the first diode D1 is connected with the feedback end 6 of the voltage reduction chip U1, the feedback end 6 of the voltage reduction chip U1 is connected with one end of the first resistor R1, the other end of the first resistor R1 is grounded, the feedback end 6 of the voltage reduction chip U1 is connected with one end of the second resistor R2, the other end of the voltage reduction chip R2 is connected with the voltage reduction chip U36, the voltage output end 1 of the voltage reduction chip U1 is connected with the power input end of the fan to provide power for the fan, wherein the voltage reduction chip U1 maintains the voltage of the feedback end 6 at a preset voltage value by adjusting the voltage of the voltage output end 1. When the temperature of the temperature sensor collecting the cooling object rises, the voltage output by the temperature sensor increases, the voltage of the output end of the first operational amplifier is reduced, the current passing through the third resistor R3 is increased, the voltage of the feedback end 6 of the voltage reduction chip U1 is reduced, and in order to maintain the voltage of the feedback end 6 of the voltage reduction chip U1 unchanged, the voltage of the voltage output end of the voltage reduction chip is increased, so that the voltage of two ends of the fan is increased, and the rotating speed is accelerated. The temperature of the cooling object is reduced in the opposite way. The invention realizes the direct temperature acquisition to adjust the rotating speed of the fan, forms closed-loop control of temperature and heat dissipation conditions, and saves the resources of the main control chip.
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 description of the embodiments or the prior art will be briefly described below.
Fig. 1 is a schematic circuit structure diagram of a fan speed regulation circuit according to an embodiment of the present invention;
fig. 2 is a schematic circuit structure diagram of another fan speed regulation circuit provided in the embodiment of the present invention.
Detailed Description
The invention discloses a fan speed regulation circuit, which can be realized by appropriately improving process parameters by taking the contents of the circuit as reference by a person skilled in the art. It is expressly intended that all such similar substitutes and modifications which would be obvious to one skilled in the art are deemed to be included in the invention. While the methods and applications of this invention have been described in terms of preferred embodiments, it will be apparent to those of ordinary skill in the art that variations and modifications in the methods and applications described herein, as well as other suitable variations and combinations, may be made to implement and use the techniques of this invention without departing from the spirit and scope of the invention.
With the development of technology, many electronic devices, such as a Central Processing Unit (CPU), a single chip, etc., generate heat because many calculations and transactions are performed. These electronic devices may burn out if not well heat dissipated. Air cooling, i.e. heat dissipation by a fan, is a common heat dissipation method in the industry. But for the fan power supply, let the fan work always and will let the fan can both carry out effectual heat dissipation to most circumstances, need great rotational speed, will produce two following problems like this: firstly, the power consumption of the fan is always constant, which causes energy waste; secondly, the fan always works at a larger rotating speed to generate noise.
At present, two speed regulation modes of a direct current fan are available, one mode is that a fan with a speed regulation function is adopted, and a main control chip is used for controlling the rotating speed of the fan. The other is to control the voltage value of the direct current power supply of the fan through a main control chip to achieve the purpose of controlling the rotating speed. However, in both of the two modes, the resources of the main control chip need to be occupied, so that the resources of the main control chip are wasted, the temperature signals are collected, and the fan rotating speed is controlled by the algorithm and then the signals are output, so that the control difficulty and the workload are increased.
Therefore, the fan speed regulating circuit provided by the invention can directly acquire the temperature signal to regulate the rotating speed of the fan, so that closed-loop control of temperature and heat dissipation conditions is formed, the rotating speed of the fan is not required to be controlled by a main control chip, the resources of the main control chip are saved, and the workload of digital programming is reduced.
As shown in fig. 1, U1 is a voltage drop chip, U2 is a temperature sensor, U3 is a first operational amplifier, R1 is a first resistor, R2 is a second resistor, R3 is a third resistor, and D1 is a first diode. The voltage reduction chip U1 has six terminals, a terminal OUT at 1 is a voltage output terminal, a terminal INPUT at 2 is a power voltage INPUT terminal, a terminal Cboost voltage boost capacitor terminal at 3, a terminal group at 4 is a GROUND terminal, a terminal fed at 6 is a feedback terminal, a terminal ON/OFF at 7 is a power output control terminal, "+" represents a non-inverting INPUT terminal of the operational amplifier, "-" represents an inverting INPUT terminal of the operational amplifier, "GND" represents GROUND, VCC is a power supply INPUT voltage, VCCO is a voltage output terminal voltage of the voltage reduction chip U1, WD is a voltage output by the temperature sensor U2, and FD is a feedback terminal voltage of the voltage reduction chip U1.
This fan speed governing circuit includes: a voltage reduction chip U1, a temperature sensor U2, a first operational amplifier U3, a first resistor R1, a second resistor R2, a third resistor R3 and a first diode D1,
the temperature sensor U2 collects the temperature of a cooling object, the output end of the temperature sensor U2 is connected with the inverting input end of a first operational amplifier U3, the voltage output end 1 of a voltage reduction chip U1 is connected with the non-inverting input end of the first operational amplifier U3, the output end of the first operational amplifier U3 is connected with one end of a third resistor R3, the other end of the third resistor R3 is connected with the negative electrode of a first diode D1, the positive electrode of the first diode D1 is connected with the feedback end 6 of the voltage reduction chip U1, the feedback end 6 of the voltage reduction chip U1 is connected with one end of the first resistor R1, the other end of the first resistor R1 is grounded, the feedback end 6 of the voltage reduction chip U1 is connected with one end of a second resistor R2, the other end of the second resistor R2 is connected with the voltage output end 1 of the voltage reduction chip U1, the voltage output end 1 of the voltage reduction chip U1 is connected with the power input end of, the buck chip U1 keeps the voltage of the feedback terminal 6 at a predetermined voltage value by adjusting the voltage at the voltage output terminal 1.
Alternatively, the voltage-reducing chip U1 may employ an LM2678 voltage converter. The LM2678 voltage converter has higher conversion efficiency and is suitable for the fan speed regulation circuit.
Optionally, the voltage at the feedback terminal 6 of the buck chip U1 needs to be kept at a preset value, so when the voltage at the feedback terminal 6 changes, the buck chip changes the duty ratio, and thus changes the voltage at the voltage output terminal 1 until the voltage at the feedback terminal 6 returns to the preset value.
Optionally, a power voltage input end 2 of the voltage reduction chip U1 is connected to a dc power supply to supply power to the dc fan speed regulation circuit.
Alternatively, the voltage output by the temperature sensor U2 increases as the sensed temperature increases.
Optionally, the rotation speed of the fan adopted by the invention can be increased along with the increase of the voltage.
It should be noted that, in the present invention, the temperature sensor may adopt a temperature sensor whose output voltage is collected and whose temperature is increased and decreased, and the corresponding fan needs to adopt a fan whose rotation speed is decreased with the increase of voltage. It is within the scope of the present invention to specifically use what temperature sensor and fan are within the scope of the present invention without departing from the principles of the present invention.
Optionally, the temperature sensor U2 needs to be powered by a power supply, and a power supply voltage input terminal of the temperature sensor U2 may be connected to a voltage output terminal of the buck chip U1, so that the buck chip U1 supplies power to the temperature sensor U2. Such connections do not affect the implementation of the present invention.
Optionally, the first operational amplifier U3 needs to be powered by a power supply, and a power supply voltage input terminal of the first operational amplifier U3 may be connected to a voltage output terminal of the buck chip U1, so that the buck chip U1 supplies power to the first operational amplifier U3. Such connections do not affect the implementation of the present invention.
When the temperature of the temperature sensor collecting the cooling object rises, the voltage output by the temperature sensor increases, the voltage of the output end of the first operational amplifier is reduced, the current passing through the third resistor R3 is increased, the voltage of the feedback end 6 of the voltage reduction chip U1 is reduced, and in order to maintain the voltage of the feedback end 6 of the voltage reduction chip U1 unchanged, the voltage of the voltage output end of the voltage reduction chip is increased, so that the voltage of two ends of the fan is increased, and the rotating speed is accelerated. The temperature of the cooling object is reduced in the opposite way. The invention realizes the direct temperature acquisition to adjust the rotating speed of the fan, forms closed-loop control of temperature and heat dissipation conditions, and saves the resources of the main control chip.
It should be noted that, when the current in the R3 becomes larger, it is equivalent to that the first resistor R1 is connected in parallel with a smaller resistor, so that the voltage at the feedback end, and because the first resistor R1 is connected in series with the second resistor R2, the voltage at the feedback end 6, that is, the voltage across the R1 becomes smaller, and in order to maintain the preset voltage value of the feedback end 6, the voltage reduction chip U1 increases the duty ratio, so that the voltage at the voltage output pin is increased, and the first resistor R1 may divide into more voltages until the feedback end 6 recovers the preset voltage value.
In an embodiment, as shown in fig. 2, in the buck chip in fig. 2, U2 is a temperature sensor, U3 is a first operational amplifier, U4 is a second operational amplifier, R1 is a first resistor, R2 is a second resistor, R3 is a third resistor, R4 is a fourth resistor, R5 is a fifth resistor, R6 is a sixth resistor, R7 is a seventh resistor, R8 is an eighth resistor, R9 is a ninth resistor, R10 is a tenth resistor, C1 is a sixth capacitor, C2 is a second capacitor, C3 is a third capacitor, C4 is a fourth capacitor, C5 is a fifth capacitor, C6 is a first capacitor, D1 is a first diode, D2 is a second diode, and L is an inductor. The voltage reduction chip U1 has six terminals, a terminal OUT at 1 is a voltage output terminal, a terminal INPUT at 2 is a power voltage INPUT terminal, a terminal Cboost voltage boost capacitor terminal at 3, a terminal group at 4 is a GROUND terminal, a terminal fed at 6 is a feedback terminal, a terminal ON/OFF at 7 is a power output control terminal, "+" represents a non-inverting INPUT terminal of the operational amplifier, "-" represents an inverting INPUT terminal of the operational amplifier, "GND" represents GROUND, VCC is a power supply INPUT voltage, VCCO is a voltage output terminal voltage of the voltage reduction chip U1, WD is a voltage output by the temperature sensor U2, and FD is a feedback terminal voltage of the voltage reduction chip U1.
Optionally, in a specific embodiment, the power voltage input terminal 2 of the buck chip is connected to a dc power supply, and the ground terminal 4 and the power output control terminal 7 of the buck chip are grounded.
Optionally, in a specific embodiment, the fan speed regulation circuit further includes: a second operational amplifier U4 for the second,
the output terminal of the temperature sensor U2 is connected to the non-inverting input terminal of the second operational amplifier U4, the inverting input terminal of the second operational amplifier U4 is grounded, and the output terminal of the second operational amplifier U4 is connected to the inverting input terminal of the first operational amplifier U3.
The second operational amplifier U4 can amplify the output voltage of the temperature sensor U2, and since most of the voltages output by the temperature sensor are relatively small, amplification by the operational amplifier is required, but if a temperature sensor capable of outputting a sufficient voltage is used, amplification of the voltage by the operational amplifier is not required.
Optionally, the second operational amplifier U4 needs to be powered by a power supply, and a power supply voltage input terminal of the second operational amplifier U4 may be connected to a voltage output terminal of the buck chip U1, so that the buck chip U1 supplies power to the second operational amplifier U4. Such connections do not affect the implementation of the present invention.
Optionally, in a specific embodiment, the fan speed regulation circuit further includes: the inductance L is provided with a plurality of inductors,
one end of the inductor L is connected to the voltage output terminal 1 of the buck chip U1, and the other end of the inductor L is connected to the non-inverting input terminal of the first operational amplifier U3.
It should be noted that the inductor L has a filtering function.
Optionally, in a specific embodiment, the fan speed regulation circuit further includes: the second diode D2 is provided in the second,
the anode of the second diode D2 is grounded, and the cathode of the second diode D2 is connected to the voltage output terminal 1 of the buck chip U1.
Optionally, in a specific implementation, the fan speed regulation circuit further includes: a first capacitor C1, a second capacitor C2, a third capacitor C3 and a fourth capacitor C4,
one end of the first capacitor C1 is connected with the voltage input end 2 of the buck chip U1, and the other end of the first capacitor C1 is grounded;
one end of the second capacitor C2 is connected with the voltage input end 2 of the buck chip U1, and the other end of the second capacitor C2 is grounded;
one end of the third capacitor C3 is connected with the voltage output end 1 of the buck chip U1, and the other end of the third capacitor C3 is grounded;
one end of the fourth capacitor C4 is connected with the voltage output end 1 of the buck chip U1, and the other end of the fourth capacitor C4 is grounded;
the first capacitor C1, the second capacitor C2, the third capacitor C3 and the fourth capacitor C4 are used as filtering capacitors in the fan speed regulating circuit.
It should be noted that filtering can reduce the ripple of the voltage and the current passing through the circuit, and the waveform becomes smooth.
Optionally, in a specific embodiment, the fan speed regulation circuit further includes: the fifth capacitance C5 is provided,
the fifth capacitor C5 is connected between the voltage output terminal 1 of the buck chip U1 and the boost capacitor terminal 3 of the buck chip U1, and serves as an energy-extracting capacitor.
It should be noted that the fifth capacitor C5 can increase the input voltage, so that the internal loss of the buck chip U1 is reduced, thereby increasing the efficiency of the power supply.
Optionally, in a specific embodiment, the fan speed regulation circuit further includes: a sixth capacitor C6 and a fourth resistor R4,
one end of a sixth capacitor C6 is connected with the inverting input end of the first operational amplifier U3, the other end of the sixth capacitor C6 is connected with one end of a fourth resistor R4, and the other end of the fourth resistor R4 is connected with the output end of the first operational amplifier U3;
the sixth capacitor C6, the fourth resistor R4 and the operational amplifier form an integral circuit.
It should be noted that the integration circuit may be used for integration compensation in the feedback control.
Optionally, in a specific embodiment, the fan speed regulation circuit further includes: a fifth resistor R5 and a sixth resistor R6,
a voltage output end 1 of the buck chip U1 is connected with a non-inverting input end of the first operational amplifier U3, specifically, the voltage output end 1 of the buck chip U1 is connected with a fifth resistor R5, and the fifth resistor R5 is connected with a non-inverting input end of the first operational amplifier U3;
one end of the sixth resistor R6 is connected with the non-inverting input end of the first operational amplifier U3, and the other end of the sixth resistor R6 is grounded;
the fifth resistor R5 and the sixth resistor R6 are used as balance resistors in the fan speed regulating circuit.
It should be noted that the balancing resistor can eliminate the influence of the static base current on the output voltage, and the magnitude of the balancing resistor should be balanced with the equivalent resistance value of the external dc path of the two input terminals.
Optionally, in a specific embodiment, the fan speed regulation circuit further includes: a seventh resistor R7, an eighth resistor R8, a ninth resistor R9 and a tenth resistor R10,
one end of the seventh resistor R7 is connected with the inverting input end of the first operational amplifier U3, and the other end of the seventh resistor R7 is connected with the output end of the second operational amplifier U4;
one end of the eighth resistor R8 is connected to the output end of the second operational amplifier U4, and the other end of the eighth resistor R8 is connected to the inverting input end of the second operational amplifier U4;
one end of the ninth resistor R9 is connected with the inverting input end of the second operational amplifier U4, and the other end of the ninth resistor R9 is grounded;
one end of a tenth resistor R10 is connected with the output end of the temperature sensor U2, and the other end of the tenth resistor R10 is connected with the non-inverting input end of the second operational amplifier U4;
the seventh resistor R7, the eighth resistor R8, the ninth resistor R9 and the tenth resistor R10 are used as balance resistors in the fan speed regulating circuit.
It should be noted that the balancing resistor can eliminate the influence of the static base current on the output voltage, and the magnitude of the balancing resistor should be balanced with the equivalent resistance value of the external dc path of the two input terminals.
Optionally, in the dc fan speed regulation circuit shown in fig. 2, VCCO is FD (R2/R1+1), the voltage at the non-inverting input terminal of the operational amplifier is VCCO R6/(R5+ R6), and the voltage at the inverting input terminal of the operational amplifier is WD (1+ R4/R5).
The invention discloses a fan speed regulation circuit, which comprises: a voltage reduction chip U1, a temperature sensor U2, a first operational amplifier U3, a first resistor R1, a second resistor R2, a third resistor R3 and a first diode D1, wherein the temperature sensor U2 collects the temperature of a temperature reduction object, the output end of the temperature sensor U2 is connected with the inverting input end of the first operational amplifier U3, the voltage output end 1 of the voltage reduction chip U1 is connected with the non-inverting input end of the first operational amplifier U3, the output end of the first operational amplifier U3 is connected with one end of the third resistor R3, the other end of the third resistor R3 is connected with the negative electrode of the first diode D1, the positive electrode of the first diode D1 is connected with the feedback end 6 of the voltage reduction chip U1, the feedback end 6 of the voltage reduction chip U1 is connected with one end of the first resistor R1, the other end of the first resistor R1 is grounded, the feedback end 6 of the voltage reduction chip U1 is connected with one end of the second resistor R2, the other end of the voltage reduction chip R2 is connected with the voltage reduction chip U36, the voltage output end 1 of the voltage reduction chip U1 is connected with the power input end of the fan to provide power for the fan, wherein the voltage reduction chip U1 maintains the voltage of the feedback end 6 at a preset voltage value by adjusting the voltage of the voltage output end 1. When the temperature of the temperature sensor collecting the cooling object rises, the voltage output by the temperature sensor increases, the voltage of the output end of the first operational amplifier is reduced, the current passing through the third resistor R3 is increased, the voltage of the feedback end 6 of the voltage reduction chip U1 is reduced, and in order to maintain the voltage of the feedback end 6 of the voltage reduction chip U1 unchanged, the voltage of the voltage output end of the voltage reduction chip is increased, so that the voltage of two ends of the fan is increased, and the rotating speed is accelerated. The temperature of the cooling object is reduced in the opposite way. The invention realizes the direct temperature acquisition to adjust the rotating speed of the fan, forms closed-loop control of temperature and heat dissipation conditions, and saves the resources of the main control chip.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
All the embodiments in the present specification are described in a related manner, and the same and similar parts among the embodiments may be referred to each other, and each embodiment focuses on the differences from the other embodiments.
The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall fall within the protection scope of the present invention.
Claims (10)
1. The fan speed regulation circuit is characterized by comprising: a voltage reduction chip (U1), a temperature sensor (U2), a first operational amplifier (U3), a first resistor (R1), a second resistor (R2), a third resistor (R3) and a first diode (D1),
the temperature sensor (U2) collects the temperature of a cooling object, the output end of the temperature sensor (U2) is connected with the inverting input end of the first operational amplifier (U3), the voltage output end (1) of the voltage reduction chip (U1) is connected with the non-inverting input end of the first operational amplifier (U3), the output end of the first operational amplifier (U3) is connected with one end of the third resistor (R3), the other end of the third resistor (R3) is connected with the negative electrode of the first diode (D1), the positive electrode of the first diode (D1) is connected with the feedback end (6) of the voltage reduction chip (U1), the feedback end (6) of the voltage reduction chip (U1) is connected with one end of the first resistor (R1), the other end of the first resistor (R1) is grounded, the feedback end (6) of the voltage reduction chip (U1) is connected with one end of the second resistor (R2), the other end of the second resistor (R2) is connected with a voltage output end (1) of the voltage reduction chip (U1), the voltage output end (1) of the voltage reduction chip (U1) is connected with a power input end of a fan to provide power for the fan, and the voltage reduction chip (U1) enables the voltage of the feedback end (6) to be maintained at a preset voltage value by adjusting the voltage of the voltage output end (1).
2. The fan speed control circuit of claim 1, further comprising: a second operational amplifier (U4),
the output end of the temperature sensor (U2) is connected with the non-inverting input end of the second operational amplifier (U4), the inverting input end of the second operational amplifier (U4) is grounded, and the output end of the second operational amplifier (U4) is connected with the inverting input end of the first operational amplifier (U3).
3. The fan speed control circuit of claim 1, further comprising: an inductance (L),
one end of the inductor (L) is connected with a voltage output end (1) of the voltage reduction chip (U1), and the other end of the inductor (L) is connected with a non-inverting input end of the first operational amplifier (U3).
4. The fan speed control circuit of claim 1, further comprising: a second diode (D2) for the first diode,
the anode of the second diode (D2) is grounded, and the cathode of the second diode (D2) is connected with the voltage output end (1) of the buck chip (U1).
5. The fan speed control circuit of claim 1, further comprising: a first capacitor (C1), a second capacitor (C2), a third capacitor (C3) and a fourth capacitor (C4),
one end of the first capacitor (C1) is connected with the voltage input end (2) of the buck chip (U1), and the other end of the first capacitor (C1) is grounded;
one end of the second capacitor (C2) is connected with the voltage input end (2) of the buck chip (U1), and the other end of the second capacitor (C2) is grounded;
one end of the third capacitor (C3) is connected with the voltage output end (1) of the buck chip (U1), and the other end of the third capacitor (C3) is grounded;
one end of the fourth capacitor (C4) is connected with the voltage output end (1) of the buck chip (U1), and the other end of the fourth capacitor (C4) is grounded;
the first capacitor (C1), the second capacitor (C2), the third capacitor (C3) and the fourth capacitor (C4) are used as filtering capacitors in the fan speed regulating circuit.
6. The fan speed control circuit of claim 1, further comprising: a fifth capacitance (C5),
the fifth capacitor (C5) is connected between the voltage output end (1) of the buck chip (U1) and the boost capacitor end (3) of the buck chip (U1) and serves as an energy-taking capacitor.
7. The fan speed control circuit of claim 1, further comprising: a sixth capacitor (C6) and a fourth resistor (R4),
one end of the sixth capacitor (C6) is connected with the inverting input end of the first operational amplifier (U3), the other end of the sixth capacitor (C6) is connected with one end of the fourth resistor (R4), and the other end of the fourth resistor (R4) is connected with the output end of the first operational amplifier (U3);
the sixth capacitor (C6), the fourth resistor (R4) and the operational amplifier form an integrating circuit.
8. The fan speed control circuit of claim 1, further comprising: a fifth resistor (R5) and a sixth resistor (R6),
the voltage output end (1) of the buck chip (U1) is connected with the non-inverting input end of the first operational amplifier (U3), and the voltage output end (1) of the buck chip (U1) is specifically configured to be connected with the fifth resistor (R5), and the fifth resistor (R5) is connected with the non-inverting input end of the first operational amplifier (U3);
one end of the sixth resistor (R6) is connected with the non-inverting input end of the first operational amplifier (U3), and the other end of the sixth resistor (R6) is grounded;
the fifth resistor (R5) and the sixth resistor (R6) are used as balance resistors in the fan speed regulating circuit.
9. The fan speed control circuit of claim 2, further comprising: a seventh resistor (R7), an eighth resistor (R8), a ninth resistor (R9), and a tenth resistor (R10),
one end of the seventh resistor (R7) is connected with the inverting input end of the first operational amplifier (U3), and the other end of the seventh resistor (R7) is connected with the output end of the second operational amplifier (U4);
one end of the eighth resistor (R8) is connected with the output end of the second operational amplifier (U4), and the other end of the eighth resistor (R8) is connected with the inverting input end of the second operational amplifier (U4);
one end of the ninth resistor (R9) is connected with the inverting input end of the second operational amplifier (U4), and the other end of the ninth resistor (R9) is grounded;
one end of the tenth resistor (R10) is connected with the output end of the temperature sensor (U2), and the other end of the tenth resistor (R10) is connected with the non-inverting input end of the second operational amplifier (U4);
the seventh resistor (R7), the eighth resistor (R8), the ninth resistor (R9) and the tenth resistor (R10) are used as balance resistors in the fan speed regulating circuit.
10. The fan speed regulation circuit of claim 1, wherein the voltage output by the temperature sensor (U2) increases with an increase in the sensed temperature.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911318552.6A CN110792624A (en) | 2019-12-19 | 2019-12-19 | Fan speed regulation circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911318552.6A CN110792624A (en) | 2019-12-19 | 2019-12-19 | Fan speed regulation circuit |
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| CN110792624A true CN110792624A (en) | 2020-02-14 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201911318552.6A Pending CN110792624A (en) | 2019-12-19 | 2019-12-19 | Fan speed regulation circuit |
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102400933A (en) * | 2010-09-17 | 2012-04-04 | 鸿富锦精密工业（深圳）有限公司 | Fan drive circuit |
| CN102852843A (en) * | 2012-08-31 | 2013-01-02 | 北京机械设备研究所 | Temperature-controlled speed-regulating circuit for direct-current fan |
| US20140070749A1 (en) * | 2012-09-11 | 2014-03-13 | Hsien-Chang Chiu | Fan speed control circuit |
| CN205101266U (en) * | 2015-10-20 | 2016-03-23 | 上海斐讯数据通信技术有限公司 | Control fan speed's automatic voltage regulation circuit |
| CN206960994U (en) * | 2017-05-25 | 2018-02-02 | 华通信安(北京)科技发展有限公司 | A kind of temperature control voltage adjusting circuit |
| CN208024608U (en) * | 2017-12-12 | 2018-10-30 | 纽福克斯光电科技（上海）有限公司 | charger fan speed regulating circuit |
| CN209543166U (en) * | 2019-01-29 | 2019-10-25 | 晟道科技石家庄有限公司 | A kind of On-Board Vehicle DC/DC Converter temperature control rotation speed of fan circuit |
| CN211116745U (en) * | 2019-12-19 | 2020-07-28 | 北京德亚特应用科技有限公司 | Fan speed regulation circuit |
-
2019
- 2019-12-19 CN CN201911318552.6A patent/CN110792624A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102400933A (en) * | 2010-09-17 | 2012-04-04 | 鸿富锦精密工业（深圳）有限公司 | Fan drive circuit |
| CN102852843A (en) * | 2012-08-31 | 2013-01-02 | 北京机械设备研究所 | Temperature-controlled speed-regulating circuit for direct-current fan |
| US20140070749A1 (en) * | 2012-09-11 | 2014-03-13 | Hsien-Chang Chiu | Fan speed control circuit |
| CN205101266U (en) * | 2015-10-20 | 2016-03-23 | 上海斐讯数据通信技术有限公司 | Control fan speed's automatic voltage regulation circuit |
| CN206960994U (en) * | 2017-05-25 | 2018-02-02 | 华通信安(北京)科技发展有限公司 | A kind of temperature control voltage adjusting circuit |
| CN208024608U (en) * | 2017-12-12 | 2018-10-30 | 纽福克斯光电科技（上海）有限公司 | charger fan speed regulating circuit |
| CN209543166U (en) * | 2019-01-29 | 2019-10-25 | 晟道科技石家庄有限公司 | A kind of On-Board Vehicle DC/DC Converter temperature control rotation speed of fan circuit |
| CN211116745U (en) * | 2019-12-19 | 2020-07-28 | 北京德亚特应用科技有限公司 | Fan speed regulation circuit |
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