JPH06344996A - Heater incorpolating substrate - Google Patents

Abstract

PURPOSE:To provide a heater incorporating substrate capable of warming up quickly electronic parts under very low temperature without needing large heater electric power for retaining the heat of the electronic parts. CONSTITUTION:When a heater 1 for heating electronic parts 11 is embedded in a substrate 2 as a pattern near right below a position of packaging the electronic parts 11, the electronic parts 11 are heated directly and concentrically by the heater 1, so that large electric power for the heater is not needed uselessly for retaining the heat of the parts 11 and the parts 11 can be warmed up quickly to the temperature of operable condition when an electronic apparatus is transferred to the operating condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate accommodated in an electronic device used in an extremely low temperature environment such as outer space, and in particular, mounted electronic parts in a non-operating state are supercooled. The present invention relates to a heater-embedded substrate configured so that mounted electronic components can be placed in a heated state by a heater embedded therein in advance so that the mounted electronic components are not exposed to the heat.

[0002]

2. Description of the Related Art Conventionally, most electronic devices mounted on artificial satellites are always in an operating state. Therefore, in such a case, Japanese Patent Laid-Open No. 4-163299
As described in Japanese Patent Laid-Open Publication No. 2003-242, it has been pointed out that electronic parts are placed in a high heat generation state, and there has been an urgent need to develop efficient heat diffusion technology and cooling technology. On the other hand, conversely to the above, in order to use electronic devices in a cryogenic environment such as outer space, it is necessary to consider that each electronic component housed inside the electronic device is not supercooled. It has become necessary. This is because when each electronic component is placed in a supercooled state, the performance as a component may be deteriorated or the component itself may be destroyed due to the supercooling.

Here, the electronic equipment according to the prior art which is used in a cryogenic environment such as outer space will be described.
FIG. 6 shows an internal configuration of the example. In this case, the glass epoxy resin substrate 2 on which the electronic components 11 as circuit components are mounted or the circuit pattern 12 is formed on the surface of the substrate is formed of an aluminum alloy chassis 13 or the like through an aluminum alloy chassis. It is housed inside the housing 14. Further, the aluminum alloy casing 14 has a heat dissipation surface 16 on the outer periphery thereof, and most of the aluminum alloy casing 14 is covered with the multilayer heat insulating material 15. I / O is suppressed. Further, in order to keep the inside of the casing 14 warm, a heater 1 for keeping warm is attached to the chassis 13 and the casing 14.

The operation will now be described. If the electronic device is in an operating state, each electronic component 11 is in a heat generating state, but the heat generated from each electronic component 11 is the substrate 2 and the chassis 13. The heat radiation surface 16 radiates the outer space through the housing 14. At that time, the heat radiation from the heat radiation surface 16 must be necessary and sufficient. This is because the thermal resistance existing between the electronic component 11 and the heat dissipation surface 16 causes a temperature difference between them. Therefore, when the heat dissipation from the heat dissipation surface 16 is insufficient and the temperature of the electronic component 11 cannot be suppressed below the allowable upper limit temperature, the electronic component 11 is in an overheated state, and in the worst case, This is because the electronic component 11 is thermally destroyed. In order to eliminate such a problem, in order to keep the temperature on the heat dissipation surface 16 at a low temperature, the amount of heat dissipation is Q, the temperature of the heat dissipation surface is Tw, the temperature of the universe is Ts, the heat dissipation surface area is A, and the heat dissipation surface is A. Let the emissivity on the surface be ε, and
Assuming that σ is a Stefan-Boltzmann constant, an equation expressing radiative heat transfer at that time, that is, Q = σεA (T ⁴ w−T
^As can be seen from ⁴ s), it is necessary to secure a sufficiently large heat dissipation surface area A corresponding to the temperature.

On the other hand, when the electronic device is in a non-operating state and each electronic component 11 is not in a heat generating state, the electronic component 1
Each of the housings 1 needs to be maintained at a temperature equal to or higher than the allowable lower limit temperature, and the inside of the housing 14 is heated by the heater 1 so that heat does not flow from the electronic component 11 to the heat dissipation surface 16. The heat dissipation surface 16 as a part of the electronic component 11
The same temperature is maintained.

[0006]

As can be seen from the above, when the electronic equipment is kept in the non-operating state for a long period of time while being exposed to the cryogenic environment, the electronic equipment housed inside the electronic equipment is kept. There is a risk that the performance of the parts will be deteriorated due to supercooling and the parts themselves may be destroyed, so it is necessary to take measures for heat retention. However, in the case of the above-mentioned conventional technique, the heater is heated in a state where it is attached to a portion where heat retention is not required, and since the electronic component is indirectly heated by heat conduction from the heater, Not only is a large amount of heater power required for heat retention, but more power and time are needed to warm up the electronic components to a temperature at which they can operate when the electronic devices are put into operation. Has been required. By the way, the method of always completely covering the outer circumference of the electronic device with a heat insulating cover, or completely covering the outer circumference of the electronic device with the heat insulating cover only when the electronic device is in a non-operating state is not considered. Unfortunately, unfortunately, it is currently difficult to implement such a method for various reasons.

An object of the present invention is to store electronic components in an extremely low temperature environment without requiring a large heater power to keep the electronic components warm and to keep the electronic devices in an operating state. When it is moved, it is necessary to provide a heater-embedded substrate that can be warmed up quickly to a temperature at which electronic components can operate.

[0008]

According to the mounting position of an electronic component on the surface of the substrate, a heater for heating the electronic component is embedded as a pattern in the vicinity immediately below the mounting position on the surface of the substrate. Can be achieved.

[0009]

When a heater for heating the electronic component is buried in a pattern immediately below the electronic component mounting position, the electronic component is directly and intensively heated by the heater. In order to maintain the heat of the electronic parts, a large heater power is not required, and when the electronic devices are brought into the operating state, the electronic parts can be quickly warmed up to the operable temperature.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to FIGS. First, the basic structure of the heater-embedded substrate according to the present invention will be described. FIG. 1 shows the structure in a sectional state. As shown in the figure, the electronic components 11 as circuit components are mounted on both surfaces of the substrate 2,
The circuit pattern 12 is formed as desired. At that time, a heater 1 for heating each electronic component 11 is provided inside the substrate 2 immediately below the mounting position of each electronic component 11 at the time of manufacturing the substrate. The pattern is embedded in advance. Naturally, heater 1
A power supply line for supplying electric power to the heater 1 is drawn in the pattern layer in which is embedded. Each of the heaters 1 has a thermal resistance of the substrate 2 and a power supply voltage,
When the resistance value and the like are set appropriately in consideration of the allowable temperature range and the allowable temperature increase rate of the electronic component 11, the temperature of each electronic component 11 can be controlled as desired.

Here, assuming a case where the heater-embedded substrate according to the present invention is housed inside the electronic device, when the electronic device is in an operating state, the heat radiation surface of the same size is used as in the case so far. Although it requires an area, when it is in a non-operating state, each of the electronic components 11 is only locally heated by the heater 1 embedded in the substrate 2 itself, and the chassis 13 and the housing 14 are not heated. It is not necessary to keep the same temperature as the electronic component 11. In other words, the temperature on the heat dissipation surface 16 is lower than that of the conventional ones. According to the above-mentioned formula, the amount of heat radiated from the same heat radiation surface area is smaller in the electronic device according to the present invention than in the past, and therefore the electric power supplied to the heater 1 is smaller accordingly. It is done. FIG. 2 shows a comparative example of the heat retention temperature and the heat retention power in the electronic device according to the related art and the electronic device according to the present invention. However, even if the heat retention temperature is set to −20 ° C., the present invention will be described. It can be seen that the electronic device according to (1) consumes less electric power. Further, FIG. 3 shows a comparative example of the temperature rise history during heating of the heater under the condition of the same heat generation amount. From now on, the one according to the present invention is more excellent than the electronic device according to the related art. It turns out that it can be warmed up quickly.

Further, the substrate with a built-in heater according to the present invention will be described. FIG. 4 is a plan view of the substrate with a built-in heater provided with a thermostat (mechanical type). The embedding mode of the heater 1 is the same as in the case of FIG. As shown, the plane of the layer in which the heater 1 is embedded is shown, and the mounting position of the electronic component 11 is shown as a dotted line display frame. In addition, a mechanical thermostat 4 is also arranged on the surface of the substrate 2 near the electronic component 11, and a power source from the outside is drawn into the power line 3 and then connected to the heater 1 via the thermostat 4. It has become a thing. When the thermostat 4 is set to mechanically operate below the preset heat retention temperature, electric power is applied to the heater 1 via the thermostat 4 while the temperature falls below the preset heat retention temperature.
The temperature of the electronic component 11 is always controlled to be the preset heat retention temperature.

A further different substrate having a built-in heater according to the present invention will be described. FIG. 5 shows a thermostat (electronic type).
2 is a plan view of a heater built-in substrate including the above. The embedding mode of the heater 1 is the same as that described so far. As shown, the plane of the layer in which the heater 1 is embedded is shown, and the mounting position of the electronic component 11 is shown as a dotted line display frame. Further, on the surface of the substrate 2 in the vicinity of the electronic component 11, an electronic thermostat 4 is also arranged with its temperature measuring probe (composed of a temperature sensitive element such as a thermistor) 5 arranged near the electronic component 11. A power source from the outside is drawn into the power source line 3, and then connected to the heater 1 via the stabilizing power source 6 and the thermostat 4. The stabilizing power supply 6 arranged near the electronic component 11 on the same substrate 2 functions only as an operating power supply to the thermostat 4 and a power supply source to the heater 1. The stabilizing power supply 6 is required because instability as the power supply cannot be avoided when the external power supply is a solar cell. As with the mechanical type, if the thermostat 4 is set to operate electronically below the set heat retention temperature, the stabilized power supply 6 and the thermostat 4 should be turned on while the temperature drops below the set heat retention temperature. Power is supplied to the heater 1 via the heater 1, so that the temperature of the electronic component 11 is constantly controlled so as to reach the preset temperature.

[0014]

As described above, according to the first to fourth aspects of the present invention, in the state of being housed inside the electronic device under the cryogenic environment, the heater power is unnecessarily large for keeping the temperature of the electronic component. In addition, a heater-embedded substrate is obtained which can be warmed up quickly to a temperature at which the electronic component can operate when the electronic device is brought into an operating state.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of an example of a heater-embedded substrate according to the present invention.

FIG. 2 is a diagram showing a comparative example of a heat retaining temperature and a heat retaining power in the electronic device according to the related art and the electronic device according to the present invention.

FIG. 3 is a diagram showing a comparative example of temperature rise history during heating of a heater in the electronic device according to the related art and the electronic device according to the present invention.

FIG. 4 is a plan view showing the configuration of another example of the heater-embedded substrate according to the present invention.

FIG. 5 is a diagram showing a plan view of another example of the structure of the heater-embedded substrate according to the present invention.

FIG. 6 is a diagram showing an internal configuration of an electronic device according to a conventional technique used in a space environment.

[Explanation of symbols]

1 ... Heater, 2 ... Substrate, 3 ... Power supply line, 4 ... Thermostat, 5 ... Temperature measurement probe, 6 ... Stabilized power supply, 1
1 ... Electronic component, 12 ... Circuit pattern

Claims (4)

[Claims] 1. A substrate which is accommodated in an electronic component mounted state in an electronic device used in an outer space environment, wherein the electronic component is mounted in the substrate according to a mounting position of the electronic component on the surface of the substrate. A heater-embedded substrate in which a heater for heating the electronic component is embedded in a pattern immediately below the mounting position. 2. A board which is accommodated in an electronic component mounted state in an electronic device used in an outer space environment, wherein the electronic component is mounted inside the substrate according to a mounting position of the electronic component on the surface of the substrate. A heater for heating the electronic component is embedded as a pattern immediately below the mounting position, while a thermostat for controlling power supply to the heater is arranged on the surface of the substrate near the electronic component. substrate. 3. A board that is housed in an electronic component mounted state in an electronic device used in an outer space environment, wherein the electronic component is mounted inside the substrate according to the mounting position of the electronic component on the surface of the substrate. A heater for heating the electronic component is embedded as a pattern in the vicinity immediately below the mounting position, while a temperature measuring probe is arranged in the vicinity of the electronic component, and the temperature measured by the probe is measured on the substrate surface. Based on this, a heater built-in substrate in which a thermostat for controlling the power supply to the heater is arranged. 4. A board which is housed in an electronic device mounted in an environment of outer space in an electronic component mounted state, wherein the electronic component is mounted inside the substrate according to a mounting position of the electronic component on the surface of the substrate. A heater for heating the electronic component is embedded as a pattern in the vicinity immediately below the mounting position, while a temperature measuring probe is arranged in the vicinity of the electronic component, and the temperature measured by the probe is measured on the substrate surface. Based on the above, a thermostat for controlling power supply to the heater is arranged, and on the same substrate surface, an operating power supply for the thermostat and a stabilizing power supply functioning only as a power supply source for the heater are arranged. substrate.