WO2005006160A1 - Electronic device cooling control method, cooling control circuit, electronic device, and program thereof - Google Patents

Abstract

In an electronic device having a cooling mechanism for cooling an electronic circuit, dew condensation is prevented when the electronic device is moved from a low temperature atmosphere to a high temperature atmosphere. The electronic circuit (34) whose temperature is detected by a temperature sensor (42) and which is cooled by the cooling mechanism (32) is subjected to throttling control for a predetermined period of time after a start according the temperature at the start. Accordingly, it is possible to stop operation of the cooling mechanism while maintaining the cooling function by the temperature detection of the electronic circuit. Thus, it is possible to prevent dew condensation of the internal printed circuit board and internal circuit while suppressing heating of the electronic circuit.

Description

 Specification

 Electronic device cooling control method, cooling control circuit, electronic device, and program therefor

 The present invention relates to a method for controlling cooling of an electronic device having a heating element such as a semiconductor element, a cooling control circuit, an electronic device having a cooling mechanism, and a program therefor. The present invention relates to an electronic device cooling control method, a cooling control circuit, an electronic device having a cooling mechanism, and a program therefor. Background art

 Mainly, electronic devices such as information processing devices that are frequently used indoors may be placed in a low-temperature atmosphere. When an electronic device in such a low-temperature atmosphere is placed indoors and only air outside the device is rapidly heated and humidified by air conditioning or the like, the printed circuit board in the electronic device, the mounted semiconductor element, etc. May be lower than the dew point of the outside air.

 On the other hand, electronic devices are equipped with a cooling mechanism that cools them with a fan or the like in order to stabilize the operation of heating elements (semiconductor elements) inside the device. For this reason, when air outside the electronic device is sucked into the device by a fan or other blower, dew condensation occurs on members below the dew point. The tendency for dew condensation to occur becomes more pronounced as the temperature inside the equipment at startup is lower, since the temperature of the outside air determined by air conditioning and the like is almost the same.

 That is, if the temperature outside the device rises sharply while the temperature inside the device is low, components with a large heat capacity, such as electronic components and printed circuit boards, inside the device will not immediately rise to the same temperature as the outside air temperature. In this state, when the fan is activated and warm air flows into the device, the air in contact with components with large heat capacity is cooled, the relative humidity becomes 100% or more, and dew forms on the component surface. When such dew condensation occurs, insulation deterioration of a printed circuit board or a semiconductor element, ion migration, or the like is likely to occur, which causes a failure or malfunction.

Conventionally, in order to prevent this dew condensation, an electronic device is equipped with a temperature sensor that detects the outdoor temperature and a temperature sensor that detects the indoor temperature, and compares the detection outputs of both temperature sensors. Then, a method of controlling a fan has been proposed (for example, see Patent Document 1).

 [Patent Document 1]

 Japanese Unexamined Patent Publication No. Hei 7-112121 (see Figs. 1 and 3)

 However, this method requires an expensive sensor (outdoor temperature sensor) only for detecting the dew condensation environment, which causes an increase in cost. In addition, in order to prevent dew condensation inside the device, stopping the blower cooling device such as a fan at the time of startup and operation in order to prevent dew condensation inside the device requires a high-speed CPU with a large amount of heat generation. In this case, only the CPU generates heat, and there is a risk that the CPU may overheat. Disclosure of the invention

 Accordingly, an object of the present invention is to provide a cooling control method and a cooling control circuit for an electronic device for preventing the dew condensation in the electronic device while guaranteeing the operation of the electronic component even when an electronic component having a large heat generation is used. To provide an electronic device having a cooling mechanism and a program therefor.

 Another object of the present invention is to provide a cooling control method, a cooling control circuit, an electronic device having a cooling mechanism for preventing dew condensation in an electronic device without adding a temperature sensor, and a program therefor. It is in.

 Further, another object of the present invention is to provide a cooling control method of an electronic device, a cooling control circuit, an electronic device having a cooling mechanism, and a method for preventing dew condensation in an electronic device while performing necessary cooling of electronic components. It is to provide the program.

 In order to achieve this object, the present invention provides a cooling control method for an electronic device, comprising: a substrate having a plurality of electronic circuits; and a cooling mechanism for cooling the inside of the device, wherein the temperature of the electronic circuit is detected by a temperature sensor. Detecting, activating the cooling mechanism according to the temperature detected by the temperature sensor, determining whether the temperature at the time of starting the device by the temperature sensor is equal to or lower than a predetermined temperature, When the temperature is equal to or lower than a predetermined temperature, a step of operating the electronic circuit for a predetermined time at a lower frequency than normal, and after the predetermined time has elapsed, the electronic circuit is operated at the relatively high frequency for normal. Operating step.

Further, the electronic device of the present invention includes a substrate provided with a plurality of electronic circuits, and cooling the inside of the device. A cooling mechanism, a temperature sensor that detects a temperature of the electronic circuit, and a cooling mechanism that is operated in accordance with a temperature detected by the temperature sensor. A control circuit for determining whether the temperature is lower than a predetermined temperature when the device is activated.The control circuit operates the electronic circuit at a frequency lower than a predetermined time for a predetermined time. Thereafter, the electronic circuit is operated at a relatively high frequency in the normal state.

 Further, according to the present invention, in a cooling control circuit for an electronic device, comprising: a substrate having a plurality of electronic circuits; a cooling mechanism for cooling the inside of the device; and a temperature sensor for detecting a temperature of the electronic circuit. A register that receives a temperature detected by the temperature sensor; and a control circuit that activates the cooling mechanism in accordance with the temperature detected by the register. If the temperature at the time of starting the device is equal to or lower than the predetermined temperature, the electronic circuit operates at a frequency lower than normal for a predetermined time, and after the lapse of the predetermined time, the electronic circuit Operates at a relatively high frequency in the normal state.

 Further, the program of the present invention is executed by a control circuit for an electronic device including a substrate having a plurality of electronic circuits, a cooling mechanism for cooling the inside of the device, and a temperature sensor for measuring the temperature of the electronic circuit. A control program for operating the cooling mechanism according to the temperature detected by the temperature sensor, and determining whether the temperature at the time of starting the device by the temperature sensor is equal to or lower than a predetermined temperature; and If the temperature is equal to or lower than the predetermined temperature, the electronic circuit operates at a frequency lower than normal for a predetermined time, and after the predetermined time elapses, the electronic circuit operates at a relatively high frequency during normal operation. Is executed by the electronic circuit.

 In the present invention, the throttling control of the electronic circuit is performed from the start, so that the operation of the cooling mechanism can be stopped while maintaining the cooling function by detecting the temperature of the electronic circuit. As a result, it is possible to prevent the condensation on the internal printed circuit board and the internal circuit while suppressing the heat generation of the electronic circuit. Also, in this case, since a special temperature sensor is not required, cost up can be prevented.

In the present invention, preferably, the step of operating at a low frequency includes a step of setting the predetermined time according to a temperature at the time of starting the device. This Finer dew condensation prevention control can be performed according to the temperature inside the device when the device is started, and the electronic circuit can return to normal operation immediately.

 In the present invention, preferably, the step of operating at the low frequency includes a step of setting the value of the low frequency according to the temperature at the time of starting the device. This makes it possible to perform more precise dew condensation prevention control in accordance with the temperature inside the device when the device is started up, and the electronic circuit can quickly return to normal operation.

 In the present invention, preferably, the method further comprises the step of changing the operation duty of the cooling mechanism with respect to the detected temperature when the temperature at the time of starting the device is equal to or lower than a predetermined temperature. Thus, even if the cooling mechanism is stopped to prevent condensation, it can be cooled if the electronic circuit becomes hot.

 In the present invention, preferably, the step of operating the cooling mechanism includes a step of operating an air cooling mechanism that air-cools the electronic circuit. As a result, even if the outside of the device is warm, the outside air outside the device is not sucked, so that dew condensation can be effectively prevented.

 In the present invention, preferably, the step of detecting the temperature of the electronic circuit comprises the step of detecting the temperature of CPU in the electronic circuit. As a result, dew condensation can be prevented while guaranteeing high-speed operation of the CPU.

 In the present invention, preferably, the step of operating at a low frequency comprises a step of performing a throttling operation of the CPU. As a result, heat generation of the CPU can be suppressed, and dew condensation can be effectively prevented.

 In the present invention, preferably, the step of operating at the low frequency includes setting the predetermined time according to the temperature at the time of starting the device, and setting the low frequency according to the temperature at the time of starting the device. Setting the value of. This makes it possible to perform more precise dew condensation prevention control according to the temperature inside the device at the time of device startup, and the electronic circuit can quickly return to normal operation.

In the present invention, preferably, the step of operating at a low frequency includes the step of setting the predetermined time according to the temperature at the time of starting the device, and wherein the temperature at the time of starting the device is equal to or lower than a predetermined temperature. In this case, the method further includes a step of changing an operation duty of the cooling mechanism with respect to the detected temperature. This makes it possible to perform more precise dew condensation prevention control according to the temperature inside the device when the device is started up. It can return to normal operation.

 In the present invention, preferably, the step of operating at the low frequency includes the step of setting the value of the low frequency in accordance with the temperature at the time of starting the device, and the temperature at the time of starting the device is predetermined. If the temperature is equal to or lower than the temperature, the method further includes changing an operation duty of the cooling mechanism with respect to the detected temperature. This makes it possible to perform more precise dew condensation prevention control in accordance with the temperature inside the device when the device is started, and the electronic circuit can quickly return to normal operation. Brief Description of Drawings

 FIG. 1 is a configuration diagram of an electronic device according to an embodiment of the present invention.

 FIG. 2 is a configuration diagram in a state where the cover of FIG. 1 is closed.

 FIG. 3 is a configuration diagram in the base of FIG.

 FIG. 4 is a block diagram of the circuit of the printed circuit board of FIG.

 FIG. 5 is a flowchart of a cooling process according to an embodiment of the present invention.

 FIG. 6 is an explanatory diagram of the parameter table according to the first embodiment of this invention. FIG. 7 is an explanatory diagram of the blower operating rate curve of FIG.

 FIG. 8 is an explanatory diagram of the parameter table according to the second embodiment of this invention. FIG. 9 is an explanatory diagram of the blower operating rate curve of FIG.

 FIG. 10 is an explanatory diagram of the change processing of the throttling operation of FIG. BEST MODE FOR CARRYING OUT THE INVENTION

 Hereinafter, embodiments of the present invention will be described in the order of an electronic device, a first embodiment of a cooling control process, a second embodiment, and other embodiments.

 [Electronic equipment]

 1 is a configuration diagram of an electronic device according to an embodiment of the present invention, FIG. 2 is a diagram illustrating a state in which a cover of the electronic device in FIG. 1 is closed, and FIG. 3 is an internal configuration of the electronic device in FIG. FIG. 4 is a configuration diagram of the cooling control unit of FIG.

FIG. 1 shows a notebook personal computer as an example of the electronic device. As shown in FIG. 1, the notebook personal computer 1 has a base 12 and a cover 10. And The cover 10 is connected to a base 12 by a hinge 14 and is rotatable, and a display 11 such as a liquid crystal panel is provided.

 On the other hand, the base 12 is provided with a key group 13, a flat mouse 15, and the like on its surface, and a printed board and the like described in FIG. 3 are provided inside. When the notebook personal computer 1 is not used, as shown in FIG. 2, the cover 10 is closed, and as shown in FIG. 1, the cover 10 is opened, and the notebook personal computer 1 is used.

 In such a notebook personal computer 1, the temperature of the device decreases outside or at night, especially in a cold region, and when the device is used in a heated room, dew condensation is likely to occur at the time of startup.

 As shown in FIG. 3, a printed board 30 on which electronic circuits are mounted is provided in the base 12. The printed circuit board 30 has electronic components such as a CPU (Central Processor Unit) 34 and semiconductor elements (not shown) such as a memory, an interface circuit, and an I〇control circuit, and air outside the device for cooling these components. And a blower (fan) 32 for supplying air to the air conditioner.

 Three vents 20, 21, and 23 are provided on both sides and the bottom of the base 12, and the blower 32 blows outside air taken from the vents 20, 22 on the left and bottom sides of the figure to the CPU 34. The air is exhausted from the vent 21 on the right side. In the CPU 34, a socket chip 44 is provided with a CPU chip 40 and a temperature sensor 42 for detecting the temperature of the CPU chip 40.

 As shown in FIG. 4, the printed circuit board 30 includes a blower 32 and a CPU 34 having a temperature sensor 42, and also detects a power switch (not shown) being turned on, and detects start-up of the device by detecting ON. A circuit 36, a clock selector 39 for selecting an operation clock to be given to the CPU 34, and a control circuit for controlling the operations of the CPU 34, the blower 32, and the clock selector 39 based on the start detection signal of the start detection circuit 36 and the temperature detected by the temperature sensor 42. 37 are provided.

The control circuit 37 basically has an input register for receiving the detected temperature of the temperature sensor 42, a processing circuit, and an output register. The processing circuit operates based on a control program stored in the memory, The blower control module 37-1 that controls the blower 32 according to the detected temperature, and the startup detection signal and the temperature of the startup detection circuit 36 It has a CPU 34, a blower control module 37-1, and a control module 37-2 for controlling the operation of the clock selector 39 depending on the temperature detected by the degree sensor 42. The control program stored in the memory can be updated. For example, the control program is provided on a portable medium such as a floppy disk, a CD-ROM, and can be updated by a control program read from the portable medium. Alternatively, the control program can be downloaded from a server via a network, and can be updated with the downloaded control program.

 [First Embodiment of Cooling Control Process]

 Next, an embodiment of the cooling control process of the present invention will be described. FIG. 5 is a flowchart of a cooling control process according to an embodiment of the present invention, FIG. 6 is an explanatory diagram of a parameter table of the first embodiment of the present invention, and FIG. 7 is a first embodiment of the present invention. FIG. 7 is a relationship diagram between a blower operating rate and a CPU temperature according to the embodiment.

 Hereinafter, the processing flow of FIG. 5 will be described with reference to FIG. 6 and FIG.

 (S 10) When the information processing device (personal computer) 1 is started, the processing of the flowchart in FIG. 5 is started. That is, when the start-up detection circuit 36 mounted on the printed board 30 notifies the control circuit 37 of the start-up detection, the control module 37-2 of the control circuit 37 receives the start-up time from the temperature sensor 42. Read the temperature of.

 (S 1 2) The control module 37-2 determines whether the temperature at the time of startup is below a certain arbitrary temperature A.

 (S14) If the temperature at the time of start-up is not lower than the arbitrary temperature A, the control module 37-2 performs start-up by CPU normal operation and CPU operation. In normal operation, the control module 37-2 instructs the blower control module 37-2 to perform normal operation, and instructs the clock selector 39 to select the normal high-speed clock H-CL. As a result, the CPU 34 operates normally and operates the blower 32 at a duty (DUTY) corresponding to the temperature of the CPU 34.

(S 16) On the other hand, if the control module 37-2 detects the temperature at the time of startup below the arbitrary temperature A, the control module 37-2 operates by lowering the CPU operating frequency from the rating in accordance with the temperature at startup. Set the duty ratio (DUTY) of the throttling to be performed, the release time, and the operating rate curve X of the blower corresponding to each temperature of the CPU. That is, the control module 37-2 has a parameter table as shown in Fig.6. This parameter table stores the time until release corresponding to the CPU startup temperature, the throttling duty, and the fan operation rate curve and line (fan speed).

 For example, in the example of Fig. 6, the CPU operating rate (throttling duty) is 10%, 30%, 50% for three cases where the CPU startup temperature is 0 ° C or lower, 5 ° C or lower, and 10 ° C or lower. % And the fan operation rate curve X are stored. As shown by the dotted line in Fig. 7, the blower operating rate curve X rotates the blower in comparison with the solid line in the normal case (a characteristic in which the fan speed (operating rate) increases linearly from 60 ° C). The threshold temperature is as high as 85 ° C and the operating rate increases rapidly.

 The clock corresponding to the duty set by the clock selector 39 is selected by the control module 37-2, and the CPU 34 shifts to the throttling at the set duty DUTY. Thereby, heat generation of the CPU 34 is suppressed.

 (S18) The control module 37-2 notifies the blower operation rate curve X to the blower control module 37-1. The blower control module 37-1 detects the temperature of the CPU 34 of the temperature sensor 42, and drives the blower 32 according to the blower operating rate curve X. '

 (S20) The control module 37-2 determines whether the time corresponding to the startup temperature set in the parameter table has elapsed. If the set release time has not elapsed, the process returns to step S16. In the blower operation rate curve X, the temperature of the CPU 34 does not become the temperature at which the blower starts to operate, which is set by the blower operation rate curve X, within the time set corresponding to the temperature at the time of startup. Therefore, the blower 32 does not operate according to the determination of the blower control module 37-1. As a result, no outside air flows into the device from the air vents 20 and 22, and no dew condensation occurs on the printed circuit board 30 in the device and on the components inside the device such as the mounted semiconductor elements. After the start-up, the temperature of the printed circuit board and the semiconductor elements mounted thereon rises over a set time, and becomes higher than the dew point temperature of the air outside the apparatus.

(S22) After a lapse of the set time, the control module 37_2 releases the throttling of the CPU 34, returns the clock of the clock selector 39 to the normal clock, and sets the blower control module 37—1. In the normal state (Figure Return to 7) H). Then, the process proceeds to step S14.

 According to this embodiment, dew condensation on internal components such as a printed circuit board and a mounted semiconductor element in the information processing apparatus is prevented. Also, as shown in Fig. 7, instead of stopping the blower at all, the start-up temperature of the blower is raised, so if the temperature of the CPU 34 becomes high, the blower is started. Then, cool the CPU 34 to guarantee its operation.

 Further, the user can recognize the state in which the blower cooling device such as the fan is controlled by the throttling operation and the release from the screen and the lamp of the information processing device 1 in FIG. Then, referring to the manual, etc., the state can be arbitrarily set to be released and restored.

 [Second embodiment of cooling control processing]

 Next, a second embodiment of the cooling control process of the present invention will be described. FIG. 8 is an explanatory diagram of a parameter table according to the second embodiment of the present invention, and FIG. 9 is a diagram illustrating a relationship between a blower operating rate and a CPU temperature according to the second embodiment of the present invention.

 This embodiment is a modification of the first embodiment, in which the characteristics of the throttling duty and the blower operating rate curve are changed. Hereinafter, the processing is the same as the processing flow of FIG.

 The control module 37-2 has a parameter table as shown in FIG. This parameter table stores the time until release corresponding to the temperature at startup of CPU, the throttling duty, and the fan operating rate curve (fan speed).

That is, as shown in FIG. 8, similarly to FIG. 6, the release time is 5 minutes and 3 minutes for the three cases where the CPU startup temperature is 0 ° C. or less, 5 ° C. or less, and 10 ° C. or less. , 1 minute, CPU operation rate (throttling duty) 3 0 _^0/0, 50%, and 50%, to store the blower operating rate curve Y. As shown by the dotted line in Fig. 9, the blower operating rate curve Y is compared with the solid line in the normal case (the characteristic that the fan speed (operating rate) increases from 60 ° C to the lowest level), This is a characteristic that the threshold temperature for rotation is slightly higher at 70 ° C., and that the operation rate increases more slowly than in the first embodiment.

As described above, according to the second embodiment, the CPU temperature at the time of starting up to the arbitrary temperature A or lower When the time is detected, the duty and release time of throttling are set to values different from those of the first embodiment in accordance with the temperature at startup. In addition, the operating rate curve Y of the blower corresponding to each temperature of the CPU is set so as to be different from that of the first embodiment.

 With this setting, the CPU 34 shifts to the throttling, but within the set time, the temperature of the CPU 34 becomes the temperature at which the fan starts to operate, which is set by the fan operating rate curve Y. According to the judgment of the blower control module 37-1, the blower 3 2 operates according to the judgment that the heat generated by the CPU 34 is suppressed by the slot ring. Operates at duty DUTY.

 As a result, outside air flows into the device from the air vents 20 and 22, but the flow rate is small, and condensation inside the device such as the printed circuit board 30 and mounted semiconductor elements inside the device is reduced. The occurrence is suppressed.

 In addition, since the CPU 34 allows a higher throttling duty than the first embodiment, the information processing device 1 can perform higher-speed processing as compared with the first embodiment. . Furthermore, since the slot ring release time is short, it is possible to quickly return to normal processing.

 [Other embodiments]

 FIG. 10 is an explanatory diagram of setting such as reference and release of the throttling mode according to the embodiment of the present invention. As shown in Fig. 10, set the icon 51 of the throttling mode on the menu bar 50 of the screen of the display 11 (see Fig. 1). Clicking on this icon 51, as shown in Figure 10, brings up the throttling mode screen below the arrow in Figure 10. Thereby, the user can recognize the state in which the blower cooling device such as the fan is controlled by the throttling operation and release. Then, on this screen, you can arbitrarily cancel, cancel, or return to that state.

As described above, the present invention can be variously modified within the scope of the gist of the present invention within the spirit of the present invention, and these are not excluded from the technical scope of the present invention. For example, although a cooling mechanism has been described using a fan, a water cooling mechanism or the like may be used in the same manner, and the electronic circuit is not limited to the CPU, and a semiconductor element capable of performing throttling control (eg, a DSP, a communication circuit, etc. ) Is also applicable. Furthermore, electronic devices The present invention can be applied not only to a notebook personal computer but also to other information processing devices and digital home appliances. Industrial applicability

 In the present invention, the throttling control of the electronic circuit is performed from the start, so that the operation of the cooling mechanism can be stopped while maintaining the cooling function by detecting the temperature of the electronic circuit. As a result, it is possible to prevent the condensation on the internal printed circuit board and the internal circuit while suppressing the heat generation of the electronic circuit. Also, in this case, since a special temperature sensor is not required, cost up can be prevented.

Claims

The scope of the claims 1. A cooling control method for an electronic device, comprising: a plurality of electronic circuits on a substrate; and a cooling mechanism for cooling the inside of the device.  A step of detecting the temperature of the electronic circuit with a temperature sensor;  Activating the cooling mechanism according to the temperature detected by the temperature sensor; and determining whether the temperature at the time of starting the device by the temperature sensor is equal to or lower than a predetermined temperature.  When the temperature at the time of starting the device is equal to or lower than a predetermined temperature, a step of operating the electronic circuit at a frequency lower than normal for a predetermined time,  Operating the electronic circuit at a relatively high frequency in the normal state after the predetermined time has elapsed.  A method for controlling cooling of an electronic device, comprising: 2. The method for controlling cooling of an electronic device according to claim 1,  The steps that operate at the low! / Frequency  A method of controlling cooling of an electronic device, comprising: setting the predetermined time according to a temperature at the time of starting the device. 3. The method for controlling cooling of an electronic device according to claim 1,  The steps operating at a low frequency are as follows:  Setting the value of the low frequency according to the temperature at the time of starting the device.  A method for controlling cooling of an electronic device, comprising: 4. The cooling control method for an electronic device according to claim 1,  When the temperature at the time of starting the device is equal to or lower than a predetermined temperature, the method further includes a step of changing an operation duty of the cooling mechanism with respect to the detected temperature. A method for controlling cooling of an electronic device, comprising: 5. The method for controlling cooling of an electronic device according to claim 1,  Activating the cooling mechanism comprises activating an air cooling mechanism for air cooling the electronic circuit.  A method for controlling cooling of an electronic device, comprising: 6. The cooling control method for an electronic device according to claim 1,  The step of detecting a temperature of the electronic circuit includes a step of detecting a temperature of CPU in the electronic circuit.  A method for controlling cooling of an electronic device, comprising: 7. The cooling control method for an electronic device according to claim 6, wherein  The step of operating at the lower frequency comprises the step of throttling the CPU.  A method for controlling cooling of an electronic device, comprising: 8. The method for controlling cooling of an electronic device according to claim 1,  The steps operating at a low frequency are as follows:  Setting the predetermined time according to the temperature at the time of starting the apparatus, and setting the value of the low frequency according to the temperature at the time of starting the apparatus.  A method for controlling cooling of an electronic device, comprising: 9. The cooling control method for an electronic device according to claim 1,  The step of operating at the low frequency includes the step of setting the predetermined time according to the temperature at the time of starting the device;  If the temperature at the time of starting the device is equal to or lower than a predetermined temperature, the method further includes changing an operation duty of the cooling mechanism with respect to the detected temperature. A method for controlling cooling of an electronic device, comprising: 10. The method for controlling cooling of an electronic device according to claim 1,  The step of operating at the low frequency includes setting the value of the low frequency according to a temperature at the time of starting the device,  If the temperature at the time of starting the device is equal to or lower than a predetermined temperature, the method further includes changing an operation duty of the cooling mechanism with respect to the detected temperature.  A method for controlling cooling of an electronic device, comprising: 1 1. A board with a plurality of electronic circuits,  A cooling mechanism for cooling the inside of the device,  A temperature sensor for detecting a temperature of the electronic circuit;  A control circuit that operates the cooling mechanism in accordance with the temperature detected by the temperature sensor and that determines whether the temperature at the time of starting the device by the temperature sensor is equal to or lower than a predetermined temperature,  The control circuit, when the temperature at the time of starting the device is equal to or lower than a predetermined temperature, operates the electronic circuit for a predetermined time at a lower frequency than normal, and after the predetermined time has elapsed, the electronic circuit operates at the normal time. Operate at relatively high frequency  An electronic device, comprising: 1 2. In the electronic device according to claim 1,  The control circuit includes:  The predetermined time is set according to the temperature at the time of starting the device.  An electronic device that specializes in that. 1 3. In the electronic device of claim 1,  The control circuit includes:  Set the low-frequency ^ (direct) according to the temperature at the time of starting the device.  An electronic device, comprising: 1 4. The electronic device according to claim 1, The control circuit changes an operation duty of the cooling mechanism with respect to the detected temperature when the temperature at the time of starting the device is equal to or lower than a predetermined temperature.  An electronic device, comprising: 1 5. The electronic device according to claim 1,  The cooling mechanism comprises an air cooling mechanism for air cooling the electronic circuit.  An electronic device, comprising: 1 6. In the electronic device of claim 1,  The temperature sensor comprises a temperature sensor for detecting a temperature of CPU in the electronic circuit.  An electronic device, comprising: 1 7. The electronic device according to claim 16, wherein:  The control circuit performs a throttling operation of the CPU.  An electronic device, comprising: 1 8. The electronic device according to claim 1,  The control circuit includes:  The predetermined time is set according to the temperature at the time of starting the device, and the value of the low frequency is set according to the temperature at the time of starting the device.  An electronic device, comprising: 1 9. The electronic device according to claim 1,  The control circuit sets the predetermined time according to the temperature at the time of starting the device, and, when the temperature at the time of starting the device is equal to or lower than a predetermined temperature, changes an operation duty of the cooling mechanism with respect to the detected temperature. Do An electronic device characterized by that. 20. In the electronic device according to claim 11,  The control circuit sets the value of the low frequency in accordance with the temperature at the time of starting the device, and when the temperature at the time of starting the device is equal to or lower than a predetermined temperature, the control circuit controls the cooling mechanism with respect to the detected temperature. Change the operating duty  An electronic device, comprising: 21. A cooling control circuit for an electronic device comprising: a substrate having a plurality of electronic circuits; a cooling mechanism for cooling the inside of the device; and a temperature sensor for detecting a temperature of the electronic circuit.  A register for receiving a temperature detected by the temperature sensor;  A control circuit for operating the cooling mechanism in accordance with the temperature detected by the register, wherein the control circuit determines whether the temperature at the time of starting the device by the temperature sensor is equal to or lower than a predetermined temperature, When the temperature is equal to or lower than a predetermined temperature, the electronic circuit operates for a predetermined time at a lower frequency than normal, and after the predetermined time elapses, the electronic circuit operates at a relatively high frequency for normal operation.  A cooling control circuit for an electronic device, comprising: 22. A control program executed by a control circuit for an electronic device including a substrate having a plurality of electronic circuits, a cooling mechanism for cooling the inside of the device, and a temperature sensor for the temperature of the electronic circuit. ,  Activating the cooling mechanism in accordance with the temperature detected by the temperature sensor, and determining whether the temperature at the time of device startup by the temperature sensor is equal to or lower than a predetermined temperature; and Operating the electronic circuit at a lower frequency than normal for a predetermined time, and operating the electronic circuit at a relatively high frequency for normal after the predetermined time has elapsed.  A control program to be executed by the electronic circuit.