JP2690221B2 - Semiconductor integrated circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor integrated circuit.

[0002]

2. Description of the Related Art A conventional semiconductor integrated circuit has a power supply terminal 53 and a ground terminal 5 as shown in the block diagram of FIG.
In general, any semiconductor circuit 15 formed corresponding to No. 4 is enclosed in a package 16 having high thermal resistance.

In such a conventional semiconductor integrated circuit, when any semiconductor circuit 15 is operating, the power supply terminal 53 is used.
The current I _cc1 further flows into the package 16, and the semiconductor chip temperature T _c of the semiconductor circuit 15 gradually rises in correspondence with the ambient temperature T _a where the package 16 is placed. FIG. 6 shows the ambient temperature T of the package 16.
_{In the} graph showing the relationship between _a and the semiconductor chip temperature T _c , when the power is not supplied from the power supply terminal 53, that is, when the semiconductor chip temperature T _c is not operating, the ambient temperature T _a as shown by the dashed line 107 in FIG. And the semiconductor chip temperature T _c have the same relationship. Next, when power is supplied to the semiconductor circuit 15 from the power supply terminal 53 and the semiconductor circuit 15 enters an operating state, power is consumed and heat is generated inside the semiconductor circuit 15, and the semiconductor chip temperature T _c is _calculated according to the following equation. To rise.

T_c= T_a+ I_cc1・ V_cc・ R_th  I_cc1: Any semiconductor circuit 15
Circuit current V_cc : Power supply voltage R_th : Thermal resistance of package In this case, as shown in FIG.
_aAnd semiconductor chip temperature T_cIs a function like the solid line 108
In charge of the ambient temperature range 105 of the package 16
T_a1~ T_a2Then, the semiconductor chip temperature T_cTemperature range
106 is T as shown in FIG._c1~ T_c2Becomes

[0005]

In the above-described conventional semiconductor integrated circuit, as shown in FIG. 6, the semiconductor chip temperature also changes due to the change in ambient temperature. Since the circuit element used in the semiconductor integrated circuit is affected by the characteristic value and the like depending on the temperature, it is necessary to design the circuit in consideration of the change in the semiconductor chip temperature.
Even if a circuit is designed in consideration of this temperature characteristic, the characteristics and functions of the semiconductor chip additionally have temperature characteristics, and there is a drawback that a stable semiconductor integrated circuit cannot be obtained.

[0006]

A semiconductor integrated circuit of the present invention is a semiconductor integrated circuit which is formed by enclosing an arbitrary semiconductor circuit in a predetermined package, and as a temperature assurance circuit built in the package, A temperature detection circuit whose output voltage changes according to the temperature of a semiconductor chip including the arbitrary semiconductor circuit, and a reference voltage whose temperature coefficient of the output reference voltage is different from the temperature coefficient of the output voltage of the temperature detection circuit. A power source, an output voltage of the temperature detection circuit, a comparison circuit that compares a reference voltage output from the reference voltage source, and a heating circuit whose power consumption is controlled and adjusted by the output voltage of the comparison circuit, It is configured with.

[0007]

Next, the present invention will be described with reference to the drawings.

FIG. 1 is a conceptual block diagram showing the configuration of an embodiment of the present invention. As shown in FIG. 1, the semiconductor integrated circuit of the present invention includes an arbitrary semiconductor circuit 1 and a temperature compensation circuit 2 corresponding to a power supply terminal 51 and a ground terminal 52, and is enclosed in a package 3. Composed. Also,
2 is a block diagram showing an embodiment of the temperature compensating circuit 2 in FIG. 1, and as shown in FIG.
A reference voltage source 4, a temperature compensating circuit 5, a comparing circuit 6, and a heat generating circuit 7 are provided corresponding to 1 and the ground terminal 52.

In FIG. 1 and FIG. 2, in the operating state in which power is supplied from the power supply terminal 51, the temperature detecting circuit 5 detects the rise of the semiconductor chip temperature,
A temperature detection voltage corresponding to the semiconductor chip temperature is output and input to the comparison circuit 6. Further, a predetermined reference voltage is supplied from the reference voltage source 4 to the comparison circuit 6, and this reference voltage and the temperature detection voltage are compared and collated in the comparison circuit 6 to obtain a difference voltage between them. A corresponding control signal is input to the heat generation circuit 7, and the heat generation temperature is controlled and adjusted. Through this temperature adjusting action, the heat generation temperature of the heat generating circuit 7 is adjusted in accordance with the rise of the semiconductor chip temperature, corresponding to the arbitrary semiconductor circuit 1 shown in FIG. 1, and the temperature inside the package 3 is kept constant. To be done.

FIG. 3 is a circuit diagram showing an embodiment of the temperature compensation circuit 2 shown in FIGS. 1 and 2.
Corresponding to the power supply terminal 51 and the ground terminal 52, a reference voltage source 4, a comparison circuit 6 including a constant current source 8, PNP transistors 9, 10 and an NPN transistor 11, a constant current source 12, and a plurality of series-connected plural current sources. The temperature detecting circuit 5 including the diode 13 and the heat generating circuit 7 using the NPN transistor 14 as a heat source are provided.

In FIG. 3, the semiconductor chip temperature T which is desired to be constantly stabilized during the operation of the semiconductor integrated circuit.
_cc, relative to the upper limit temperature T _a2 of ambient temperature T _a, T _cc
> T _a2 . Further, with respect to the temperature coefficient of the voltage V _d which is a negative coefficient by the temperature coefficient of the forward voltage of the diode _{t d (V / ° C)} , the temperature coefficient of the voltage V _s of the reference voltage source 4 t _s (V / ° C) is set so that t _d <t _s, and the voltage V _s of the reference voltage source 4 and the voltage V _d in the temperature detection circuit 5 correspond to the temperature coefficients t _d and t _s . It is set such that V _d = V _{s at} the stable temperature T _cc of the semiconductor chip. Next, the collector current I ₁₄ of the NPN transistor 14 which is the heat source in the heat generating circuit 7 is the lower limit temperature T _a1 of the operating ambient temperature T _a.
In order to raise the semiconductor chip temperature T _c to the stable temperature T _cc , the following expression is satisfied with respect to the lower limit temperature T _a1 of the operating ambient temperature.

T_cc> T_a1+ (I_cc1+ I_cc2) ・ V_cc・ R_th  I_cc2= I₈+ I₁₂+ I₁₄  Where I₈And I₁₂Are current sources 8 and 1 respectively
2 is a constant current value.

Next, at the ambient operating temperatures T _{a1 to} T _a2 ,
The operation of the temperature compensation circuit will be described. In FIG. 3, immediately after the power is turned on, the semiconductor chip temperature T _c
Is at a temperature lower than the stable temperature T _cc , and V _d > V _s
Therefore, the PNP transistor 10 included in the comparison circuit 6 is in a non-conductive state, the PNP transistor 9 is in a conductive state, and the NPN transistor 11 and the NPN of the heat source are included.
A current flows into the transistor 14. NPN of heat source
Since the transistor 14 consumes a considerable amount of power, it generates heat, which raises the semiconductor chip temperature T _c . When the semiconductor chip temperature T _c reaches the stable temperature T _cc , V _d = V _s , the collector current of the PNP transistor 10 increases, and the collector current of the PNP transistor 9 decreases. For this purpose, the NPN transistor 1
1 and the current flowing into the heat source NPN transistor 14 also decreases. Therefore, the NPN transistor 1 of the heat source
The power consumption of No. 4 also decreases and the amount of heat generation thereof also decreases, and the stable temperature T _cc converges to the temperature shown by the following equation, and the semiconductor chip temperature T _c stabilizes at the current I _cc2 .

T_cc= T_a+ V_cc・ (I_cc1+ I_cc2) ・ R_th  FIG. 4 shows the circumference of the package 3 in FIG.
Ambient temperature T_aAnd semiconductor chip temperature T_cA graph showing the relationship with
When the power is not supplied from the power supply terminal 51,
That is, in the non-operating state, the dashed line 102 in FIG.
As shown, the ambient temperature T_aAnd semiconductor chip temperature T_c
And have the same relationship. That is, T_c= T_aBecomes Next
Power is supplied from the power supply terminal 51 to the semiconductor circuit 1.
Then, when any semiconductor circuit 1 becomes operational, the temperature
Power is supplied from the power supply terminal 51 also in the compensation circuit 2.
You. Temporarily, only the arbitrary semiconductor circuit 1 is sealed in the package 3.
Ambient temperature T_aAnd semiconductor chip
Temperature T_cThe relationship with is as follows.

T_c= T_a+ V_cc・ I_cc・ R_th  That is, the relationship shown by the solid line 103 in FIG.
And the ambient temperature T_aChanges, the semiconductor chip temperature T
_cAlso changes. Then, as shown in FIG.
The semiconductor circuit 1 and the temperature compensation circuit 2 are packaged in the same package.
If the device is operated by enclosing it in the No. 3 unit, the safety of the semiconductor integrated circuit is reduced.
Constant temperature T_ccIs a temperature compensation circuit as expressed by the following equation.
Circuit current I of path 2_cc2Changes to T_c= T_cc(Constant)
Held in the state of.

T_cc= T_a+ V_cc・ (I_cc1+ I_cc2) ・ R_th  Ambient temperature T in this case_aAnd semiconductor chip temperature
T_c(Stabilization temperature T_cc), The relationship between
It is indicated by the line 104.

[0017]

As described above, according to the present invention, the temperature compensating circuit for keeping the temperature of the semiconductor circuit at a predetermined constant temperature is enclosed in the same package, corresponding to the semiconductor circuit having an arbitrary function. By forming the semiconductor integrated circuit in this manner, it is possible to prevent deterioration of the electrical characteristics of the semiconductor integrated circuit that corresponds to changes in the ambient temperature and maintain high reliability.

[Brief description of the drawings]

FIG. 1 is a conceptual block diagram showing an embodiment of the present invention.

FIG. 2 is a block diagram showing an embodiment of a temperature compensation circuit in the embodiment.

FIG. 3 is a circuit diagram showing an embodiment of the temperature compensation circuit.

FIG. 4 is a graph showing a relationship between an ambient temperature and a semiconductor chip temperature in the example.

FIG. 5 is a conceptual block diagram showing a conventional example.

FIG. 6 is a graph showing a relationship between ambient temperature and semiconductor chip temperature in a conventional example.

[Explanation of symbols]

 1, 15 Semiconductor circuit 2 Temperature compensation circuit 3, 16 Package 4 Reference voltage source 5 Temperature detection circuit 6 Comparison circuit 7 Heating circuit 8, 12 Constant current source 9, 10 PNP transistor 11, 14 NPN transistor 13 Diode

Claims (1)

(57) [Claims] 1. A semiconductor integrated circuit formed by enclosing an arbitrary semiconductor circuit in a predetermined package.
As a temperature guarantee circuit built in the package, a temperature detection circuit in which an output voltage changes according to the temperature of a semiconductor chip including the arbitrary semiconductor circuit, and a temperature coefficient of a reference voltage output is the temperature detection circuit. A reference voltage source having a temperature coefficient different from that of the output voltage, a comparison circuit that compares the output voltage of the temperature detection circuit and a reference voltage output from the reference voltage source, and the output voltage of the comparison circuit A semiconductor integrated circuit, comprising: a heat generating circuit for controlling and adjusting the amount of electric power.