RU1781813C - Device for temperature stabilization of capacitance of varactor diode - Google Patents

Description

1

(21) 4804460/09 (22) 21.03.90 (46) 12.15.92. Bull №46

(71) Research Institute of Measuring Instruments

(72) K.A. Kolupaev

(56) Altshuller GB, Elfimov N.N., Shakulin V.G. Economical miniature quartz oscillators M. Svyaz 1979, p. 89, fig. 6.2.

(54) DEVICE FOR TEMPERATURE STABILIZATION OF VARACTOR DIODE CAPACITY

(57) The invention relates to radio engineering, communications technology and can be used in the design of tunable filters, phase shifters, resonators, etc. The purpose of the invention is to improve the accuracy of stabilization. The device comprises two diodes, a constant bias voltage source, two resistors with corresponding connections between them. 2 ill.

The invention relates to radio engineering, communications technology and can be used in the design of tunable filters of phase shifters, resonators, etc.

The purpose of the invention is the expansion of the dynamic range

In FIG. 1 is a circuit diagram of a device; figure 2 presents the current-voltage characteristics of the diodes at different temperatures.

The device contains a first, second heat-sensitive elements made on diodes 1, 2, first, second resistors 3,4, a source 5 of a constant bias voltage, a common bus 6

The device operates as follows.

When the input voltage is zero, diode 1 is closed and diode 2 is open, so the output voltage is almost equal to the voltage drop across resistor 3, which corresponds to the intersection points of the load line 1 with the current-voltage characteristic of diode 2 at different temperatures in Fig. 2 descriptions. At temperature Т2 (Т1 Т2 ТЗ), the output voltage is 11out1. With increasing temperature, the capacitance of a varactor diode increases, but at the same time as the temperature increases, the output voltage also increases, and since an increase in voltage on a varactor diode decreases its capacitance, the capacitance of a varactor diode will be stabilized. Similarly, with decreasing temperature, the capacitance of a varactor diode decreases and simultaneously the voltage at the output of the circuit, which also stabilizes the capacitance of the varactor diode. As the voltage at the input increases, the diode 1 opens. At the same time, current will flow from the input through the open diode 1, resistors 3 and 4 to the common bus. The output voltage will be equal to the sum of the voltage drops across the resistors 3 and 4. With an increase in the ambient temperature, the voltage drop across the diodes 1,2 decreases, which leads to an increase in the output voltage and, accordingly, stabilization of the capacitance of the varactor diode.

with C

i41

00 00 CO

decreasing temperature, decreasing the output voltage stabilizes the capacitance of the varactor diode.

With a further increase in the input voltage, the diode 2 closes. The current flowing from the input through the diode 1 and resistors 3 and 4 creates a voltage drop in the last 1) output2 (Fig. 2, the point of intersection of the load line 2 with the current-voltage characteristic of the diode 1). Due to the diode properties indicated above, the output voltage stabilizes the capacitance of the varactor diode.

The type of diodes 1, 2 and the values of resistors 3 and 4 are selected so as to compensate for the temperature dependence of the capacitance of the varactor diode in the range of voltage variation at the input of the device.

The magnitude of the electromotive force E of the constant bias voltage source is chosen to be equal to the voltage drop across the diode 2 at the lowest operating temperature TK (Fig. 2 of the description). Thus, the output voltage is practically

L

Figure 1

It is equal to zero, and the maximum is determined by the breakdown voltage of the varactor diode, therefore, the device increases the dynamic range of output voltages to the maximum possible value.

Claims (1)

SUMMARY OF THE INVENTION A device for temperature stabilization of a varactor diode capacitance comprising first and second diodes, first and second resistors, a constant bias voltage source, the first terminal of which is connected to the first terminal of the first resistor and a common bus, the first electrodes of the same name of the first and second diodes are connected respectively with an input for supplying a control signal and a second output of a constant bias voltage source, and with the second terminals of the same name with a load and with a second terminal the first- resistor, characterized in that, in order to increase the accuracy of stabilization, a second resistor connected between the second You are a same name. waters of the first and second diodes. F Tf 72 73 AND Shh. fig g