CN1258818A - Stepless fan speed temperature controller and control method - Google Patents
Stepless fan speed temperature controller and control method Download PDFInfo
- Publication number
- CN1258818A CN1258818A CN 98126000 CN98126000A CN1258818A CN 1258818 A CN1258818 A CN 1258818A CN 98126000 CN98126000 CN 98126000 CN 98126000 A CN98126000 A CN 98126000A CN 1258818 A CN1258818 A CN 1258818A
- Authority
- CN
- China
- Prior art keywords
- control voltage
- pulse
- temperature
- circuit
- fan
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Control Of Positive-Displacement Air Blowers (AREA)
- Cooling Or The Like Of Electrical Apparatus (AREA)
- Control Of Electric Motors In General (AREA)
Abstract
The controller includes one control voltage generator circuit, one pulse modulating circuit coupled to the control voltage generator circuit to generate modulated signal through modulating clock signal and one fan driving circuit coupled to the pulse modulating circuit to regulate fan speed according to the modulated signal. The control process includes the steps of sensing temperature with temperature sensing element, producing one control voltage based on the sensed signal, modulating clock signal with the control voltage to produce one modulated pulse signal and regulating fan speed with the modulated signal.
Description
The present invention is relevant for a kind of device and controlling method thereof of controlling rotation speed of the fan, particularly a kind of device of non-section type fan speed temperature and controlling method thereof, it can directly carry out the rotating speed control of non-section type to the fan of heat transmission, can adjust the rotating speed of fan by this on the ground of property and mobility at any time, it is worked, to reach heat radiation and power consumption the optimum state between the two under the minimum speed of enough heat radiations.
General device the time all produces heat in running, similarly is the electronic equipment of working at high speed especially, and the phenomenon of very high temperature more may appear in for example little processing of high speed (high-speed miroprocessor) when operation.The variety of issue that causes in order to prevent that temperature is too high shortens or stroke defect or the like as component life, the temperature when general electronic equipment all can be adorned some sink and reduces operation.
Common radiating mode has two kinds at present.First kind of radiating mode is the function that reaches heat radiation with mechanical structure, and be general more common as finned or guide plate or the like.The radiating effect of general radiating fin or deflector structure is in contact with it the association that area has certain degree, and in general, the radiating fin area of contact heals big radiating effect better, otherwise it is relatively poor then to dispel the heat.Therefore, there is narrow limitation in the radiating mode of this mechanical mechanism, for the strict portable electronic devices of component size (as notebook computer), just can't utilize mechanical radiating structure to reach needed cooling-down effect fully, particularly when the very fast situation of service speed of portable electronic devices, the heat radiation of limited heat diffusion area is to reach the purpose of heat radiation fully.Second kind of radiating mode then is to utilize fan or other cooling units to reach diffusing purpose.Because the fan volume is less, therefore to need the portable electronic devices of quick heat radiating mainly all be to dispel the heat with fan to great majority.
Present most of heat transmission fan all is to adopt to decide Control of Voltage, that is fan can be at the two states that starts or cut out, and is determined whether dispelling the heat by the controlling mechanism of system.But, still there is shortcoming in known fan when running.At first, fan is unlike radiating fin, necessary consumed power when dispelling the heat, and fan when running in order to reach maximum radiating effect, mostly be to adopt maximum (top) speed, so fan can consume suitable electric power in use, this obviously is a negative for the portable electronic devices of the strict control of needs power consumption.In addition, fan can make a noise when running, and is obvious especially when running up.Hence one can see that, and the two-part control of known fan obviously has suitable shortcoming, is necessary to propose improved plan.
Main purpose of the present invention is to propose a kind of device and controlling method thereof of non-section type fan speed temperature, and it can dynamically be adjusted rotation speed of the fan and reach needed radiating effect according to the state of temperature in the electronic equipment.
For the present invention that achieves the above object takes following measure:
The control gear of first kind of non-section type rotation speed of the fan that the present invention proposes, comprise (1) control voltage generation circuit, it has the temperature sensor that can be used to the sensor device temperature, as thermistor (termister), the control voltage generation circuit then according to this temperature sensor for sense temperature, produce corresponding control voltage; (2) pulse modulated circuit, as pulse-width modulator (pulse width modulator), it is coupled to the control voltage generation circuit, and receive a modulation clock signal, Sampling is then according to received control voltage, the modulation clock signal is carried out Sampling, and produce corresponding pulse-modulated signal; And (3) rotation speed of the fan drive circuit, it is coupled to pulse modulated circuit, the rotation speed of the fan drive circuit is then according to pulse-modulated signal, adjust the rotating speed of fan, adjust the thermolysis of fan by this, only consuming under suitable electric power and the situation of generation the needed radiating effect of the system that reaches than low noise.
In addition, in above-mentioned device, temperature sensor can be counted the regional temperature sensing element by several and be constituted, and these regional temperature sensing elements are distributed on the diverse location of equipment with sensing temperature, and the control voltage that is produced then can be corresponding to the mean temperature of this each position of equipment.
The control gear of second kind of automatic temperature-controlled rotation speed of the fan of non-section type comprises: (1) several control voltage generation circuits, each control voltage generation circuit has corresponding temperature sensor respectively, be distributed on each corresponding position of equipment, come the temperature of sensing on this corresponding position, and each control voltage generation circuit according to its temperature sensor for sense temperature, produce corresponding control voltage; (2) sum up weighting circuit, be coupled to above-mentioned control voltage generation circuit, can receive control all control voltages that voltage generation circuit produced, utilization produces total control voltage after respectively controlling the processing of the pairing Weighting factor sum total of voltage; (3) pulse modulated circuit is coupled to total weighting circuit, and receives a modulation clock signal, and it carries out Sampling according to master control voltage for the modulation clock signal, produces corresponding pulse-modulated signal by this; And (4) rotation speed of the fan drive circuit, be coupled to pulse modulated circuit, it adjusts the radiating efficiency of fan by this according to the rotating speed of pulse-modulated signal adjustment fan, only consuming under suitable electric power and the situation of generation the needed radiating effect of the system that reaches than low noise.
The present invention takes following structure:
The device of a kind of non-section type fan speed temperature of the present invention is characterized in that, comprising:
One control voltage generation circuit, it has temperature sensor, and in order to the temperature of sensor device, the control voltage generation circuit for sense temperature, produces the control voltage of a correspondence according to temperature sensor;
One pulse modulated circuit is coupled to the control voltage generation circuit and receives a modulation clock signal, according to control voltage, carries out a Sampling for the modulation clock signal, and produces the pulse-modulated signal of a correspondence; And
One rotation speed of the fan drive circuit is coupled to pulse modulated circuit, and it adjusts the rotating speed of fan according to pulse-modulated signal.
The device of another kind of non-section type fan speed temperature of the present invention is characterized in that, comprising:
At least two control voltage generation circuits, each control voltage generation circuit has corresponding temperature sensor respectively, place on the corresponding position of equipment, in order to the temperature of sensor device on corresponding position, each control voltage generation circuit for sense temperature, produces corresponding control voltage according to temperature sensor;
One sum total weighting circuit is coupled to the control voltage generation circuit, in order to receive the control voltage of control voltage generation circuit, handles with the Weighting factor sum total of correspondence, produces a sum total control voltage;
One pulse modulated circuit is coupled to the sum total weighting circuit and receives a modulation clock signal, and it carries out a Sampling for the modulation clock signal, and produce the pulse-modulated signal of a correspondence according to sum total control voltage; And
One rotation speed of the fan drive circuit is coupled to pulse modulated circuit, and it adjusts the rotating speed of fan according to pulse-modulated signal.
The controlling method of a kind of non-section type fan speed temperature of the present invention applicable to the equipment with fan, may further comprise the steps:
Utilize temperature sensor, the temperature of sensor device;
According to the temperature sensor signal of temperature sensor to equipment, produce a control voltage, it is corresponding to the mean temperature of equipment.
Utilize control voltage modulated one modulation clock signal, produce a pulse-modulated signal;
Utilize pulse-modulated signal, adjust the rotating speed of fan.
Conjunction with figs. and embodiment are as follows to the detailed description of the invention:
The accompanying drawing simple declaration:
Fig. 1: the detailed circuit diagram of first embodiment of the invention non-section type fan speed temperature device.
Fig. 2: the detailed circuit diagram of second embodiment of the invention non-section type fan speed temperature device.
Fig. 3: the flow chart of fan rotational frequency control method of the present invention.
The control gear of rotation speed of the fan of the present invention mainly is to utilize temperature sensor (being thermistor among the embodiment) to come the temperature in the sensing electronic equipment, and the result according to temperature sensing produces the rotating speed that a pulse-modulated signal is controlled fan again.Therefore, this device can be according to the state of temperature in the electronic equipment, and the rotating speed of fan is adjusted on continuity ground, makes it present harmony between the two, that is, when temperature in the electronic equipment rises, can flexibly heighten the rotating speed of fan, increase its radiating efficiency; When temperature in the electronic equipment descends, also can flexibly reduce the rotating speed of fan, reduce its power consumption and suppress the noise of its generation.
As shown in Figure 1, it is that first embodiment's fan rotation speed control apparatus comprises control voltage generation circuit 2, pulse modulated circuit 4 and circuit for controlling speed of fan 6, is used for state according to temperature in the electronic equipment, flexibly controls the rotating speed of fan 8.
Control voltage generation circuit 2 comprises resistance R 1, thermistor R2 and the resistance R 3, R4 and the operational amplifier OP1 that constitute amplification circuit.Resistance R 1 and thermistor R2 are the relation of series connection, and are coupled between voltage source V CC and the grounding end.According to the electric resistance partial pressure principle, voltage V1 can be expressed as on the contact of resistance R 1 and thermistor R2:
V1＝R2×VCC/(R1+R2) (1)
Thermistor R2 is as temperature sensor in an embodiment, and is on certain special position that is placed in the electronic equipment to be controlled, and the resistance value of thermistor R2 then can change along with the temperature on the special position simultaneously.According to the relation of (1) formula, when the resistance value of thermistor R2 changed, branch pressure voltage V1 also can be along with change.Therefore, the magnitude of voltage of branch pressure voltage V1 is comprising the message status of temperature in the electronic equipment.Then branch pressure voltage V1 is imported into the non-oppisite phase end (non-inverting terminal) of operational amplifier OP1, resistance value proportionate relationship according to 4 of resistance R 3 and resistance R, branch pressure voltage V1 can be adjusted to control voltage V2, outputs to pulse modulated circuit 4.
Pulse modulated circuit 4 comprises pulse-width modulator 40, resistance R 5 and capacitor C 1.The effect of pulse modulated circuit 4 is the magnitude of voltage according to control voltage V2, for modulated pulse signal C
MCarry out pulse duration modulation (pulse width modulation), produce a pulse skin bandwidth modulation signals V3.In the present embodiment, pulse-width modulator 40 is that the employing model is the intergrated circuit of LM550, and resistance R 5 and capacitor C 1 then are its circuit peripheral element.Yet for knowing this operator,, can also constitute pulse modulated circuit 4 in the present embodiment by other elements or circuit as long as can carry out pulse duration modulation according to control voltage V2.
In pulse-width modulator 40, end points VCC and R are connected to power end VCC, and end points TR then is used for receiving modulation clock signal C to be modulated
MEnd points GND ground connection, 5 of resistance R place between end points DIS, THR and the voltage source V CC, and capacitor C 1 places between end points DIS, THR and the grounding end.End points OUT output pulse width modulation signal V3.The action of pulse-width modulator 40 can be described below.At first, receive from the control voltage V2 that controls voltage generation circuit 2, and receive modulated pulse signal C to be modulated by end points TR by end points VC
MThen utilize the magnitude of voltage of control voltage V2, adjust modulated pulse signal C
MPulse width, make the width of each pulse among the pulse width modulating signal V3 all corresponding to the state of temperature of electronic equipment at present.
Circuit for controlling speed of fan 6 is the pulse width modulating signal V3 according to input, adjusts the running rotating speed of fan 8, and in other words, the state of temperature during promptly according to electronic equipment running at present is a condition to satisfy minimum cooling demand, adjusts the rotating speed of fan 8.As shown in the figure, circuit for controlling speed of fan 6 comprises resistance R 6, resistance R 7, transistor Q1, inductor L1 and capacitor C2 in the present embodiment.Wherein, resistance R 6, R7 and transistor Q1 constitute a switching circuit.The pulse width modulating signal V3 that the base stage of transistor Q1 (base) receives from pulse modulated circuit 4 through resistance R 6.So pulse width modulating signal V3 is at the impulse duration of high levle, can turn-on transistor Q1, make the series resonant circuit that voltage source V CC feed-in inductor L1 and capacitor C2 are constituted.By this, the voltage on the capacitor C2 can change corresponding to the state of temperature of electronic equipment, makes the rotating speed of fan 8 change.
The molar behavior of above-mentioned control voltage generation circuit 2, pulse modulated circuit 4 and circuit for controlling speed of fan 6 is described below.When in the electronic equipment during temperature change, the resistance value of thermistor R2 also can be along with change, and the change direction is generally oppositely, i.e. temperature rising resistance value descends, the temperature then resistance value rising that descends.Because the resistance value of thermistor R2 changes, make the control voltage V1 of output also change thereupon.After the process processing of pulse modulated circuit 4, the pulse width among the pulse width modulating signal V3 also can be along with change.Utilize the switch motion of transistor Q1 at last, can adjust the rotating speed of fan 8, reach purpose of the present invention.
In the present embodiment, though temperature sensor is constituted with single thermistor R2, but also can utilize several thermistors that place the electronic equipment diverse location to carry out the sensing of temperature, take out control voltage by the control voltage generation circuit 2 of Fig. 1 again, can reach the purpose of present embodiment too corresponding to mean temperature in the electronic equipment.
Fig. 2 represents the detailed circuit diagram of the automatic temperature-controlled rotation speed of the fan device of non-section type among second embodiment, and the difference between itself and circuit shown in Figure 1 mainly is the processing mode on the temperature sensing.As shown in Figure 2, the automatic temperature-controlled rotation speed of the fan device of the non-section type among second embodiment comprises a plurality of control voltage generation circuit 21～2n, sum total weighting circuit 3, pulse modulated circuit 4 and circuit for controlling speed of fan 6.Second embodiment then is the thermistor that utilizes among these control voltage generation circuit 21～2n, the temperature of each position in the sensing electronic equipment to be controlled respectively, and produce respectively control voltage that should the position state of temperature.Then, with total weighting circuit 3, weighting, and produce a master control voltage, again with the processing mode shown in similar first embodiment, utilize pulse sensing circuit 4 and circuit for controlling speed of fan 6 to control the rotating speed of fan.
Control voltage generation circuit 21 comprises that resistance R 8, R9 and the operational amplifier OP3 of resistance R 1, thermistor R2 and formation amplifier constitute, control voltage generation circuit 2 among its basic function mode and first embodiment is roughly the same, but this moment, branch pressure voltage was that relation by (R8+R2)/(R8+R2+R1) is determined.According to the resistance value that thermistor R2 changes because of temperature, control voltage generation circuit 21 can produce the control voltage of corresponding this change.Basically to produce circuit 21 identical with control circuit as for other the 26S Proteasome Structure and Function of control voltage generation circuit 22～2n, repeats no more herein.
Produced control voltage by each control voltage generation circuit 21～2n, then can be sent to and be weighted (weighted) processing and addition processing in the sum total weighting circuit 3, produced master control voltage corresponding to ensemble average temperature in the electronic equipment.Comprise resistance R 11～R1n, resistance R 10 and the operational amplifier OP4 that is used for representing respectively to control the relative weights of voltage in total weighting circuit 3.Supposes respectively to control the control voltage that voltage generation circuit 21～2n produced and be respectively V21～V2n, and the master control voltage of being exported is V4 that then relation can be expressed as between the two:
Therefore, the variation of sum total control voltage can be represented the mean change amount of temperature on each position.(it is identical with first embodiment to utilize pulse modulated circuit 4 and circuit for controlling speed of fan 6, repeat no more), promptly can utilize sum total control voltage flexibly to adjust the rotating speed of fan 8, so that balance fan power consumption and device temperature relevance between the two.
Fig. 3 represents the flow chart of the automatic temperature-controlled fan rotational frequency control method of non-section type of the present invention.As shown in the figure, at first, utilize the temperature (S1) in the electronic equipment such as thermistor (may for single or several) sensing notebook computer, that is the resistance change of thermistor can be corresponding to the mean temperature variable quantity in the equipment at present.According to the resistance change of thermistor, produce control voltage (S2) with corresponding variable quantity.This control voltage is the control voltage input in the general pulse modulated circuit.Utilize this control voltage to adjust the pulse width of modulated pulse signal again, produce corresponding pwm signal (S3) by this.At last, utilize this pwm signal, adjust the rotating speed of fan, so that the control radiating efficiency.
Compared with prior art, the present invention has following effect:
The present invention can directly carry out the rotating speed control of non-section type to the fan of heat transmission, can adjust the rotating speed of fan by this on the ground of property and mobility at any time, it is worked, to reach the optimum state between heat radiation, power consumption and fan noise under the minimum speed of enough heat radiations.
Though the present invention discloses as above with a preferred embodiment, be not in order to limit protection scope of the present invention.
Claims (13)
1, a kind of device of non-section type fan speed temperature is characterized in that, comprising:
One control voltage generation circuit, it has temperature sensor, and in order to the temperature of sensor device, the control voltage generation circuit for sense temperature, produces the control voltage of a correspondence according to temperature sensor;
One pulse modulated circuit is coupled to the control voltage generation circuit and receives a modulation clock signal, according to control voltage, carries out a Sampling for the modulation clock signal, and produces the pulse-modulated signal of a correspondence; And
One rotation speed of the fan drive circuit is coupled to pulse modulated circuit, and it adjusts the rotating speed of fan according to pulse-modulated signal.
2, device according to claim 1 is characterized in that, described temperature sensor is a thermistor.
3, device according to claim 2, it is characterized in that, described control voltage generation circuit comprises one first resistance, and it is connected with described thermistor and is coupled to a voltage source, and control voltage is proportional to the branch pressure voltage on the contact of first resistance and thermistor.
4, device according to claim 1 is characterized in that, described pulse modulated circuit is a pulse-width modulator, and it is according to described control voltage, the pulse width of modulating described modulation clock signal.
5, device according to claim 1 is characterized in that, described temperature sensor is made of at least two regional temperature sensing elements, and the regional temperature sensing element places the diverse location of equipment, and described control voltage is corresponding to the mean temperature of equipment.
6, a kind of device of non-section type fan speed temperature is characterized in that, comprising:
At least two control voltage generation circuits, each control voltage generation circuit has corresponding temperature sensor respectively, place on the corresponding position of equipment, in order to the temperature of sensor device on corresponding position, each control voltage generation circuit for sense temperature, produces corresponding control voltage according to temperature sensor;
One sum total weighting circuit is coupled to the control voltage generation circuit, in order to receive the control voltage of control voltage generation circuit, handles with the Weighting factor sum total of correspondence, produces a sum total control voltage;
One pulse modulated circuit is coupled to the sum total weighting circuit and receives a modulation clock signal, and it carries out a Sampling for the modulation clock signal, and produce the pulse-modulated signal of a correspondence according to sum total control voltage; And
One rotation speed of the fan drive circuit is coupled to pulse modulated circuit, and it adjusts the rotating speed of fan according to pulse-modulated signal.
7, device according to claim 6 is characterized in that, described temperature sensor is a thermistor.
8, device according to claim 7, it is characterized in that, described control voltage generation circuit comprises one first resistance, and it is connected with described thermistor and is coupled to a voltage source, and control voltage is proportional to the branch pressure voltage on the contact of first resistance and thermistor.
9, device according to claim 6 is characterized in that, described pulse modulated circuit is to be a pulse-width modulator, and it is according to control voltage, the pulse width of modulating described modulation clock signal.
10, a kind of controlling method of non-section type fan speed temperature applicable to the equipment with fan, may further comprise the steps:
Utilize temperature sensor, the temperature of sensor device;
According to the temperature sensor signal of temperature sensor to equipment, produce a control voltage, it is corresponding to the mean temperature of equipment;
Utilize control voltage modulated one modulation clock signal, produce a pulse-modulated signal;
Utilize pulse-modulated signal, adjust the rotating speed of fan.
11, controlling method according to claim 10 is characterized in that, described temperature sensor is to be made of at least two regional temperature sensing elements, and the regional temperature sensing element places the diverse location of equipment, and control voltage is corresponding to the mean temperature of equipment.
12, controlling method according to claim 10 is characterized in that, described temperature sensor is a thermistor.
13, controlling method according to claim 10 is characterized in that, according to the mode of the described modulation clock signal of described control voltage modulated, is to adopt pulse duration modulation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN98126000A CN1089141C (en) | 1998-12-31 | 1998-12-31 | Stepless fan speed temperature controller and control method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN98126000A CN1089141C (en) | 1998-12-31 | 1998-12-31 | Stepless fan speed temperature controller and control method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1258818A true CN1258818A (en) | 2000-07-05 |
| CN1089141C CN1089141C (en) | 2002-08-14 |
Family
ID=5229447
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN98126000A Expired - Fee Related CN1089141C (en) | 1998-12-31 | 1998-12-31 | Stepless fan speed temperature controller and control method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1089141C (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100403202C (en) * | 2003-07-28 | 2008-07-16 | 华为技术有限公司 | Fan rotating speed controlling method and apparatus |
| CN100413391C (en) * | 2005-01-24 | 2008-08-20 | 大众电脑股份有限公司 | Control system and method for fan of electronic device and radiating system thereof |
| CN1758171B (en) * | 2004-10-10 | 2010-05-12 | 仁宝电脑工业股份有限公司 | Method for automatic fine regulating rotation speed of heat radiation fan |
| US7991584B2 (en) | 2007-12-06 | 2011-08-02 | Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. | System and method for testing a fan interface of a motherboard |
| CN101644276B (en) * | 2009-07-07 | 2013-10-30 | 深圳市科陆电子科技股份有限公司 | Device and method for driving DC fan |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100385369C (en) * | 2003-06-27 | 2008-04-30 | 精拓科技股份有限公司 | Apparatus and method for controlling rotation speed of multistage speed and intelligent fan |
| CN100356682C (en) * | 2004-05-18 | 2007-12-19 | 精拓科技股份有限公司 | Method and system for intelligent fan speed control |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2129839Y (en) * | 1992-03-07 | 1993-04-14 | 陈杰化 | Temperature control electric fan |
| CN2169716Y (en) * | 1993-03-18 | 1994-06-22 | 李稳立 | Controller for temp. difference control air exchanger |
| CN2254130Y (en) * | 1995-05-23 | 1997-05-14 | 周忠 | Auto-controlled variable input air control box for fan |
-
1998
- 1998-12-31 CN CN98126000A patent/CN1089141C/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100403202C (en) * | 2003-07-28 | 2008-07-16 | 华为技术有限公司 | Fan rotating speed controlling method and apparatus |
| CN1758171B (en) * | 2004-10-10 | 2010-05-12 | 仁宝电脑工业股份有限公司 | Method for automatic fine regulating rotation speed of heat radiation fan |
| CN100413391C (en) * | 2005-01-24 | 2008-08-20 | 大众电脑股份有限公司 | Control system and method for fan of electronic device and radiating system thereof |
| US7991584B2 (en) | 2007-12-06 | 2011-08-02 | Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. | System and method for testing a fan interface of a motherboard |
| CN101644276B (en) * | 2009-07-07 | 2013-10-30 | 深圳市科陆电子科技股份有限公司 | Device and method for driving DC fan |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1089141C (en) | 2002-08-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6300689B1 (en) | Electric power generating system | |
| US7479766B2 (en) | Dynamic multiphase operation | |
| US5440208A (en) | Driver circuit for electroluminescent panel | |
| CN1089141C (en) | Stepless fan speed temperature controller and control method | |
| CN1717869A (en) | Driver for switching circuit and drive method | |
| CN106253769B (en) | DC fan motor control circuit and the control method for applying it | |
| EP0569191B1 (en) | Mixed mode stepper motor controller | |
| CN108093534A (en) | Control method, controller and LED drive device | |
| CN114658680B (en) | Control method and control device for board cooling fan | |
| CN115798392A (en) | Background light adjusting method of vehicle-mounted miniLED display screen and vehicle-mounted miniLED display screen | |
| CN1661516A (en) | Method and device for controlling fan | |
| TW201143289A (en) | Power converting apparatus and power converting method | |
| CN1908740A (en) | Converter controller having feedforward compensation, converting system and method for controlling same | |
| US5841297A (en) | Circuit arrangement for driving an MOS field-effect transistor allocated to the supply circuit of an electrical load | |
| CN1913333A (en) | Drive device of fan moter | |
| CN1866147B (en) | Fan control device and method | |
| EP1343357A3 (en) | Electronic device, or dimmer, for regulating the power supply applied to a load | |
| CN1039761C (en) | Dividing driving circuit for step motor | |
| CN111697831B (en) | Control system and control method of resonant converter | |
| CN1302688C (en) | Backside light control device | |
| US8093850B2 (en) | Fan control system | |
| CN117559864B (en) | New energy vehicle motor voltage calculation method | |
| CN1314609A (en) | Hardware modelling of relative brightness of light-emitting diode | |
| CN2504824Y (en) | Control circuit for radiating system | |
| CN112260594B (en) | Brush direct current motor, drive control circuit thereof and air conditioner |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C06 | Publication | ||
| PB01 | Publication | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20020814 Termination date: 20161231 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |