GB2097184A

GB2097184A - Temperature regulating an electronic circuit module

Info

Publication number: GB2097184A
Application number: GB8202783A
Authority: GB
Original assignee: Burr Brown Research Corp
Current assignee: Burr Brown Research Corp
Priority date: 1981-04-20
Filing date: 1982-02-01
Publication date: 1982-10-27
Also published as: FR2504293A1; GB2097184B; JPS6322623B2; JPS57178349A; FR2504293B1; DE3214614A1; DE3214614C2

Abstract

A combination of heating 10 and cooling 2 elements within an electronic circuit module provide constant temperature regulation, at above or below ambient temperature, in order to achieve maximal performance from semiconductor integrated circuitry 8, 20. The temperature regulation function may be achieved with relatively low current control circuitry operating the heating element, and may be electrically isolated from the integrated circuitry. Alternatively temperature regulation may be achieved by controlling the cooling element. The module is capable of performance over at least a 50 DEG C variation in ambient temperature. <IMAGE>

Description

SPECIFICATION A method of temperatures regulating an electronic circuit module and a temperatureregulated circuit module This invention relates to the field of temperature-regulated electronic circuitry and temperatureregulating methods.

In the development and evaluation of semiconductor devices and/or semiconductor chips containing multiple devices integrated together to provide a functional electronic circuit, it became very apparent that overheating of the semiconductor devices and/or semiconductor chips was very detrimental to device or circuit performance and, in many cases, lead to destruction of the device or circuit function. Thus, it became apparent that solutions or techniques were needed to prevent device or circuit overheating and thereby avoid the resulting deterioration or destruction of the device or circuit function. Various solutions or techniques to prevent device or circuit overheating were tried or implemented in attempts to solve this problem. One such solution or technique was to provide thermoelectric cooling or semiconductor circuit elements to prevent their destruction at igh temperatures.Another solution or technique was to operatee low-power semiconductor circuits at below ambient temperature to improve their performance with respect to noise and parasitic leakage currents. In the past, such below ambient temperature operation has ordinarily been effected by means of expensive temperature chambers utilizing cooling fluids and the like which are not well suited for compact or portable equipment. Accordingly, a need existed to provide an improved technique or method for cooling semiconductor devices or chips to reduce overheating of the semiconductor devices or chips.

In accordance therefore with this invention we provide an electronic circuit module, comprising, in combination: a temperature sensitive electronic integrated circuit; thermoelectric cooling means for said circuit; and temperature-regulating means coupled to said circuit and said cooling means for controlling the temperature of said circuit.

There is also provided a method for providing temperature-regulated electronic circuitry comprising the steps of: providing an electronic circuit; cooling said electronic circuit by thermoelectric cooling means; and temperature-regulating said electronic circuit for controlling the temperature of said circuit by providing temperature-regulating means coupled to said circuit and said thermoelectric cooling means.

In preferred embodiments of the present invention to be described in detail hereinafter, temperature sensitive electronic circuitry is cooled by thermoelectric means and heated by temperature regulating integrated circuit (IC) means to maintain constant temperature of the critical circuitry over a wide range of ambient temperature, which may be either above or below the regulated temperature. In one embodiment, the regulatory means and the critical circuitry are both separated from the cooling means by a thermal impedance; relatively little power must be controlled by the regulator. Alternatively, the cooling means may be directly regulated. In either case, the cooler power supply is substantially isolated from the critical circuit power supply. Other embodiments consistent with the following objects are within the scope of the invention.

In the accompanying drawings: Figure 1 is a cross-section of a preferred embodiment of the device of Fig. 2 taken along line 1-1 and showing the major elements thereof; Figure 2 is a top view illustrating interconnection of the various elements of the device.

Referring to Figs. 1 and 2, there is shown a cross-sectional side view and a top view, respectively, of a preferred embodiment of the invention. A substrate 1 serves as a support for the other elements or components of the electronic circuitry provided thereon and also provides for heat transfer to ambient. As shown in Fig. 2, the substrate 1 in this example is the metallic base of a TO-3 type header bearing multiple pins 17 (see Fig. 1) for external connection. On top of the substrate 1 is mounted a thermoelectric cooler or cooler module 2 (see Fig. 1) activated by leads 18 connected to two of the package pins 17. The thermoelectric cooler 2 comprises an active element (vertical lines) sandwiched between a horizontal hot face mounted on the substrate 1 and a horizontal cold face mounted on and located above the active element.

(If desired, connections can be made through the faces for electrically energizing the cooler.) In the embodiment shown, a thermal insulator 4 for example Kapton, is mounted on the cold face of the thermoelectric cooper 2 and supports an isothermal insulating substrate 6, for example, made of beryllia. The substrate 6 is attached to a temperature regulating heater 10 in integrated or hybrid circuit format.

The electronic circuit function to be temperature regulated comprises one or more semicon ductor or integrated circuit chips 8 (see Fig. 2 where two chips are shown) which may be mounted on a hybrid substrate 20 bearing thin and/or thick film passive components (such as resistors, capacitors, etc.) depending on the desired circuit function. A flexible insulator 1 4 (e.g.

Kapton) bearing a printed circuit pattern provides for interconnecting of all components by means of the wire bonds 16 being connected by means of the conductors of the printed circuit pattern to the package pins 17 and to the bonding lands or the other components. The other components include, for example, an output buffer or amplifying circuit 12 mounted directly on the primary substrate 1 in order to reduce dissipation in the cooled portion of the device. By mounting any thermally non-critical components away from the cooler 2 better temperature control is achieved, as well as elimination of thermal transients and thermal feedback which would degrade the performance of the regulated circuitry.

By way of specificity, the cooler 2 may be a MELCOR thermoelectric module FC 0.6-8-06 which can provide, for example, a 65 C differential between the hot and cold faces. This temperature differential decreases approximately linearly with increased pumped power, and falls to zero at a pumped power of about 0.55 W. This is achieved with a power input to the cooler of about 0.9 watts (1A, .9V).Based on such performance, temperature regulation of, for example, a Burr-Brown BB3528 FET amplifier at - 1 0'C, would result in an input bias current of only about 7.5 FA over an ambient temperature range of 68 C according to the following example in tubular form: DROP ACROSS DROP ACROSS POWER IN COOLER INSULATOR HEATER 8 TEMP OF CASE TEMP NOTE 1 NOTE 2 AMP FET AMP -25'C -27'C 40 C 318 mW -lOC NOTE 3 25 C -51'C 1 4 C 114mW 40 C -58.6'C 6.6 C 53 mW - 10 C 43 C -60 C 5 C 40mW - 10 C NOTE 4 NOTE 5 NOTES 1.From manufacturer's data for thermoelectric cooler: T ( C) = - 65 + 120 x pumped power (Watts) (at 1A input to cooler) 2. Chosen for 5 C at 40.mW = 1 25 C/W.

3. 106mAat30V 4. Maximum case temperature for circuit temperature regulation to - 1 0'C.

5. Quiescent power of circuit and heater at - 1 0'C.

From the table, it is seen that due to the increase in dissipation of the temperature regulating IC 12, the, for example, FET amplifier (comprising the chips 8 and the passive devices on the hybrid substrate 20) is regulated at a constant temperature above or below the ambient temperature.

Not only does the regulatory circuitry and method of cooling operation, as described above, reduce the leakage current in semiconductor electronic devices, but it also lowers noise and lower drift can be obtained due to the regulation of the temperature of the critical circuitry. It also provides integral thermal regulation of an electronic circuit module at a temperature below ambient whereby improved circuit performance is achieved and enables a compact, totally electronic module with temperature regulation at a temperature below ambient to be provided.

Also integral thermal regulation with minimal temporal errors can be attained in an electronic circuit module operating at temperatures below ambient, the integral thermal regulation being achieved with relatively low current temperature control circuitry. Other configurations will be obvious to those skilled in the art based on the foregoing detailed description of the preferred embodiments. In summary, the module depicted in the Figures has a cooling feature which permits cooling (by means of cooler 2) of the electronic circuit to a desired preferred low temperature range of operation to provide better and more efficient device and circuit operation while still permitting stabilization of device and circuit performance by providing a heating feature which permits heating (by means of the semiconductor device 10) of the electronic circuit to maintain the desired cooled temperature of the circuit within a very narrow temperature range thereby increasing performance.

Claims

1. An electronic circuit module, comprising, in combination: a temperature sensitive electronic integrated circuit; thermoelectric cooling means for said circuit; and temperature-regulating means coupled to said circuit and said cooling means for controlling the temperature of said circuit.

2. The module of Claim 1 wherein said temperature-regulating means controls the temperature of said circuit at a value below the ambient temperature.

3. The module of Claim 1, wherein said temperature-regulating means controls the temperature of said circuit at a value within a range of ambient temperatures.

4. An electronic module including a temperature-sensitive integrated circuit comprising, in combination: thermoelectric cooling means for said circuit; heating means for said circuit; thermal impedance means interposed between said cooling means and both of said circuit and said heating means; and temperature-regulating means coupled to said circuit for electrically energizing said heating means to control the temperature of said circuit.

5. The module of Claim 4 wherein said temperature-regulating means controls the temperature of said circuit at a value below the ambient temperature.

6. The module of Claim 4 wherein said temperature-regulating means controls the temperature of said circuit at a value below or above the ambient temperature or at a value within a range of ambient temperatures.

7. The module of any of the preceding claims wherein said cooling means is electrically isolated from said circuit.

8. The module of any of the preceding claims further including output amplifying circuit means for said circuit, said amplifying means being thermally isolated from said circuit.

9. An electronic module including a temperature sensitive integrated circuit comprising in combination: heating means for said circuit; thermoelectric cooling means for reducing the temperature of both said circuit and said heating means; and temperature-regulating means energizing said heating means for simultaneously controlling the temperature of said circuit and said heating means.

10. A method for providing temperature-regulated electronic circuitry comprising the steps of: providing an electronic circuit; cooling said electronic circuit by thermoelectric cooling means; and temperature-regulating said electronic circuit for controlling the temperature of said circuit by providing temperature-regulating means coupled to said circuit and said thermoelectric cooling means.

11. The method of Claim 10 including the steps of heating said circuit and temperatureregulating by energizing the heating for controlling the temperature of said circuit.