SU705432A1 - Apparatus for temperature stabilization - Google Patents

Description

(54) DEVICE FOR TEMPERATURE STABILIZATION OF MICROSHEM SUBSTRATES

The invention relates to the field of radio engineering and can be used to measure and control temperature. In particular, to stabilize the substrate temperature. The devices are known that contain a thermal sensor, a heater and an Ul booster. They are used to maintain a constant temperature and temperature - sensitive components of integrated circuits. In these devices, as the temperature changes, the negative feedback loop of the closed control loop tends to keep the substrate temperature constant by varying the power, dissipating the heater. An additional heat transfer path provides high accuracy in stabilizing the temperature of the substrate. The disadvantage of these devices is the increased time to enter the mode. The closest to the invention to the technical essence is a device for temperature stabilization of the substrate of the microcircuit, containing the first thermistor included in one of the arms of the measuring bridge, the first diagonal of which is connected to the power source and the second to the inputs of the amplifier, the output of which is connected to the first input an adder whose output is connected to an actuator connected to a power source, a voltage divider whose midpoint is connected to the second input of the adder 2. The prior art provides high accuracy with smooth (slow) changes in ambient temperature. With stepwise changes in the ambient temperature, for example, when the onboard equipment is turned on and off under various climatic influences, there is a long transition process determined by electrothermal constant time of the temperature control unit. The presence of a long transient process leads to an increase in the transient component of the temperature stabilization error, an increase in the equipment availability time for operation, i.e., an important tactic — a technical parameter of the product — is worsening the ioHviro. The purpose of the present invention is to improve the accuracy of stabilization of the temperature of the supply in transient conditions. The goal is achieved by the fact that the device contains two pulse drivers, an RC-link, a series-connected subtractor and a comparator, the output / of which is connected by the first inputs of the pulse-former, the second inputs of which are connected to the output of the subtractor, and the outputs, respectively, with the third and fourth inputs of the adder The midpoint of the voltage divider is connected directly to the non-inverting and through the XX link to the inverting inputs of the subtractor. In the description of the invention, the following symbols are used; AT ttV is the deviation of the temperature of the surrounding medium from a value of 1 n more than nominal; Ug is the voltage of the divider; and - subtractor voltage: U, .j - emulsions of voltage of the waiting multivibrators; ir is the time constant of the inertial unit. FIG. 1 shows the structure of the proposed device; in fig. 2 shows the electrical circuit of the device for the temperature stabilization of the chip substrates; in fig. 3 is an electrical block diagram. optimization. The device for temperature stabilization of the microcircuit substrates is enclosed in a sealed housing 1 of the microcircuit (Fig. 1). It contains a temperature-stabilized substrate 2 and a temperature-stabilized unstabilized center Z. On a temperature-stabilized substrate 2, there are 4 chip components that are sensitive to temperature changes, and the first thermistor 5. On the substrate 2, there is also an actuator, which represents itself. thermobath ryuyu, recruited from thermoelements b, and having thermal contact with the substrate 2. The second thermistor 7 is installed on the temperature-unstable substrate 3 from the external side of the microcircuit case. The first thermistor 5 is connected to the shoulder of the measuring bridge 8 connected to the input of the amplifier 9. The output of the amplifier 9 is connected to the first input of the combiner TO, THE OUTPUT of the second is connected to the executive element 6, and the second input is connected to the midpoint of the divider on the resistor 7 and resistor 11. The second, third and fourth inputs of the mattress are connected to the optimization block 12, performed on the subtractor 13, RC chain 14, 15, KOMViaparope 16 and pulse makers 17, 18 representing positive and negative field pulses Rnness. A limiting circuit is included in the negative feedback circuit of the compressor 16, made on Zener diodes 19, 20. The non-inverted input circuit of the comparator 16 consists of resistors 21, 22, The device operates as follows. At dTd (b) 1 O measuring the bridge. . 8 is unbalanced. The unbalance voltage is fed to the input of the amplifier 9 and through the adder 10 is applied to the control transistors of the amplifiers of the actuator 6 .. 1 Depending on the sign of the unbalance, the thermopile absorbs or releases heat by adjusting the temperature of the substrate until the bridge 8 balances, eliminate the temperature deviation of the substrate of the microcircuit from the required value. The device also has a single-sided Heat Transfer Path according to the ambient temperature. The sensor of this path is a thermistor 7. The voltage from the output of the divider (7, 11) is fed to one of the inputs of the adder 10 and, depending on the sign of the signal, through one of the amplifiers of the actuating element b is fed to the input of the thermopile. The additional path compensates for the main error in temperature stabilization, and the closed loop with thermal feedback eliminates the error caused, in particular, by parametric perturbations. With significant temperature-hopping changes that take place ViPf on-off equipment under various meteorological conditions, for example, in flight conditions of aircraft, during climatic tests of equipment etc., the stabilization error can be significant and for its elimination a considerable time is required. connection with the inertia of the object. (substrate). To eliminate this error, the optimization block 12 (Fig. 3) is used, which operates at large deviations of the temperature T (t) from the value taken as nominal. For large discontinuous changes of xdTd (t), the voltage Ug goes through the inertial RC link 14, 15 to the inverted input of the subtractor 13, to the non-inverted input of which it goes directly. With the output of reader 13, the difference voltage U is removed: .H-6 VKUg-Ku e At t O, the voltage U (j K Ug-, i.e. proportional to the jump ltd (b) This voltage goes to the comparator 16. The comparator has two transfer points in accordance with the direction of voltage change U. The values of the voltages corresponding to these points are set by the voltage limitations of the zener diodes and the resistors 21, 22 in the non-inverted input circuit of the comparator 16. When the voltage U reaches the value of one of the two points the flip (depending on the sign, q) is launched by waiting for the multi vibrator 17 or 18, forming a pulse of positive or negative polarity. The pulses of the waiting multivibrators 17 or 18 - and or and, the duration of which is determined by the value U, arrive at the corresponding inputs of the adder 10, through one of the amplifiers of the actuating element 6 I apply to the thermoelements , force forcing or cooling the substrate of the microcircuit and ensuring high accuracy of stabilization in transient modes. At the same time, the optimization unit does not affect the stability of the closed control loop. The use of the optimization block favorably distinguishes the proposed device for temperature stabilization of the chip substrates from the above prototype, since in the predby device the error of the temperature stabilization under transient conditions in the transient modes is significantly reduced, which reduces the readiness of electronic equipment to work. In addition, the use of the heater - cooler as an actuator will allow maintaining the substrate temperature equal to

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Claims (2)

FigL normal (20-25s), which significantly improves the operational reliability of the chip. Apparatus of the Invention A device for temperature stabilization of microcircuit substrates containing & The first thermistor connected to one of the arms of the measuring bridge, the diagonal of which is connected to the power source and the second to the inputs of the amplifier, the output of which is connected to the first platoon of the adder, the output of which is connected to the actuator connected to the power source, is a voltage divider The midpoint of which is connected to the second input of the adder, characterized in that, in order to improve the accuracy of the devices, it contains two pulse drivers, a COP link, a series-connected subtractor and The comparator, the output of which is connected to the first inputs of the pulse formers, the second inputs of which are connected to the output of the subtractor, and the outputs, respectively, to the third and four Inverting inputs of the adder, is connected to the non-inverting inputs and through the CS link to the inverting inputs that are connected to the inverter inputs that are connected to the inverter inputs and through the CS link to the inverting inputs that are connected to the inverter inputs and connected to Sources of information taken into account during the examination 1. Matzen V.T. and others. Functional electronic components, using the No. 1e thermal phenomena - Works of the Institute of Electrical and Electronics Engineers, No. 12, V. 52, 1964, pp. 16-27. 2. Authors Certificate of the USSR №407294, cl. G 05 D 23/30, 1972 (prototype).