SU1497715A1 - Method of adjusting dc voltage converter - Google Patents

Abstract

This invention relates to the field of electronic engineering. The purpose of the invention is to simplify the setup process. A device for implementing the proposed method contains an input differential cascade 1, performed on field-effect transistors, with a resistor 2 in the source circuit of each transistor and with rm 3 dc current in the common source circuit, and also rc 4 ac, ac meter 5 voltage, potentiometer 6, DC voltage 7, resistive voltage divider 8 and key 9. Alignment of variable components at the source of the transistors does not occur by changing the resistance, but by switching the sources with the key 9. At the same time, the drift adjustment and the bias voltages and the bias adjustment itself become independent. The setup process is simplified because eliminates the complex iterative process of achieving zero readings from various meters. 1 il.

Description

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The invention relates to electronic engineering and can be used in analog and analog-1p1fractive converters of direct current voltage.

The purpose of the invention is to simplify the setup process.

The drawing shows a DC voltage converter for implementing the proposed method of setting about

The DC voltage converter contains an input differential cascade 1, made on field-effect transistors, with a resistor 2 in the source circuit of each field-effect transistor and with a DC generator 3 in the common source circuit, as well as the AC generator 4 AC voltage meter, potentiometer 6, DC amplifier 7 with differential inputs, resistive voltage divider 8 and switch 9.

To clarify the essence of the tuning method, consider the operation of a dc voltage converter. The input signal is fed to its input, amplified by an appropriate field-effect transistor, and fed to the inverting input of dc amplifier 7. The negative processing circuit of the connection through the resistive divider 8 voltage stabilizes the device conversion coefficient for the device. The main cause of the error of such devices is the bias that occurs in the input differential stage 1, as well as its temperature drift. If the bias voltage is easily compensated, then heating is required to adjust to the minimum temperature drift, which greatly complicates the adjustment and keeps the device. To eliminate this drawback, a method is used to adjust the bias voltage of the input differential stage to the minimum of the driving voltage - p-junction by adjusting the ratio of their current drain to the slope According to a known method, when maintaining the correlation

IT - it

where i, 1, are the field-effect transistors;

S ,, S 2 is their steepness, the bias voltage drift is minimal. However, a device that implements the specified tuning method requires a complex iterative tuning process and can not be applied directly, since the DC / DC converter is captured by a common feedback and is failing in its absence. As a result, the alignment of the variable components at the source of the transistors does not occur by changing the resistance, but by bridging the sources with the key 9o. In this case, the bias voltage drift is adjusted and the bias itself becomes independent.

After the key 9 is bridged, the adjustment to the minimum of the drift of the bias voltage occurs as follows. The input of the device is connected to a common bus, alternating current is supplied from the alternator 4, and by adjusting the pot meter 6, zero reading of the alternator voltage meter 5 is obtained. Wherein

and jH, Uj. "

(2)

Ujt (2 - variable gate voltage components - source of transistors,

, Ii- / s,

(3) (4)

where 1 is the variable component of the current flow of the field-effect transistors

Substituting (3) and (4) into (2), we get

Ii Ii-s sT

(five)

a since due to deep feedback

IisT

(6)

then, substituting (6) in (5), we obtain condition (1), T, e, at the indicated setting the temperature drift of the bias voltage becomes minimal. After tuning, the key 9 opens, ge14177156

nerator 4 variable. the switching current and sequentially switched on and by adjusting the resistors 2 input differential stage is compensated for the bias voltage on the field: the resistors from the resistor device. At the same time, the setting of the tempo in the source circuit of each transistor drift of the bias voltage of the torus and the DC amplifier c is not violated, since the magnitude of the co-differential inputs, by the resistance of the resistors 2 to the currents of the field sources of the transient input variable transistors are not affected by variable increment, exponential cascade 1, the equalization of alternating voltages on the adjustment process is simplified, the field-effect transistor transistors are eliminated by complex iterative adjustment current resistors, the process of achieving zero readings of the installation of zero voltage offset of various meters. or by adjusting the source

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Claims (1)

The claims are in order to simplify the process The tuning method of the tuning converter, during the adjustment of the direct current voltage of the coil resistors, combines the sources zhaivshego covered by a chain of common reverse field-effect transistors