CS207209B1 - Double-phase generator with non-inverting and double inlet integrator - Google Patents

Description

The invention relates to the connection of a two-phase generator with a non-inverting and a two-input integrator.

Prior art known circuits of two-phase generators usually consist of two inverting integrators and an inverter with feedback over the entire circuit. Damping is usually introduced into this circuit in the feedback circuit of the first integrator. Positive feedback from the output of the second integrator to the second input of the inverter ensures that the oscillation is stable and maintained. The disadvantage of prior art circuits is the necessity of using three active elements, such as operational amplifiers, which increases production costs, electrical input and at the same time worsens the background distance of generators with very little non-linear distortion. Existing circuitry causes difficulties especially in the requirement to achieve higher frequencies, where it is susceptible to oscillation even without the introduction of feedback, the non-linear distortion due to phase shift and the limited cut-off frequency for full output power strongly increases.

These two drawbacks are eliminated by a two-phase generator with a non-inverting and a two-input integrator. , with an amplitude control circuit and a fifth resistor with an inverting input of the second amplifier and a second capacitor with its output at the node with a second output terminal and a third resistor connected to the non-inverting input of the first amplifier at the node; with a first capacitor connected to a common conductor, followed by a fourth resistor while ^; the non-inverting input of the second amplifier is connected to an amplitude control circuit connected to a common conductor.

The essential advantage of the circuitry according to the invention is that it allows simple realization of two-phase 90 ° output shifting generators, with a particularly desirable small coefficient of amplitude control circuitry enabling efficient regulation while achieving very low non-linear distortion, e.g. regulation.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is illustrated in more detail by the accompanying drawing, in which an example of connection is shown. The two-phase generator consists of a feedback loop composed of a non-inverting integrator, which forms the first amplifier 1, whose inverting input is connected via a second resistor 6 to its output and through a first resistor 5 to a common conductor. The non-inverting input of the first amplifier 1 is connected via the third resistor 7 to the output of the second amplifier 2, on the one hand through the fourth

20720?

supports 8 to the node with the first output terminal 3, with the output of the first amplifier 1, with the amplitude control circuit 12j and on the other hand through the first common-capacitor 9. The two-input integrator forms a second amplifier 2 by an inverting input connected both via the fifth resistor 10 to the node of the first output terminal 3 and second through the second capacitor i to its output together with the second output ^. The non-inverting input of the second amplifier is connected to the second terminal of the amplitude control circuit 12, the third terminal of which is connected to a common wire. The amplitude control circuit 12 may be realized using, for example, non-linearity of the amplitude transmission characteristic of the double gate, thermally sensitive elements such as thermistors, bulbs, or controlled splitters, analog multipliers. The purpose of this circuit is to set and maintain the transmission coefficient to the desired one, to maintain the harmonic oscillations.

The circuit design is usually based on the values given below, and we usually choose

R _s = R ₆ , R ₇ = R ₈ = 711 ₀ = RC _u = 1/2 G, = CT = RC

The transfer of the amplitude control circuit is denoted by K.

Considering ideal elements, the following applies to a non-inverting integrator:

^U 3 = - ~ U ₄ pT where u ₃ is the voltage at the first output terminal 3 u _{4 is the} voltage at the second output terminal 4 p is a complex variable

For a two-stage integrator, ¹ V i ^K

U ₄ ---— U ₃ + K. U ₃ + —- U ₃ pT pl

Then the characteristic equation for the whole circuit is:

₂ K 1 - K _n P - y P + _T 2 - = ⁰

It follows from this equation that the circuit can work as a harmonic generator only for the transmission coefficient K = 0. The above comparison is only general, it does not respect the losses in the real elements used in the circuit. The real circuit is stable due to losses and it is necessary to set a small positive K i, less than 0.1 to create a generator

Claims (1)

SUBJECT OF THE INVENTION A two-phase non-inverting generator and a two-input integrator characterized in that the first amplifier (1) is connected via its first resistor (5) to its common conductor through its inverting input and through its second resistor (6) to its output. 3), with the fourth; a resistor (8) with an amplitude control circuit (12) and a fifth resistor (10) with an inverting input of the second amplifier (2) and a second capacitor (11) with its output at the node with the second output terminal (4) and a third resistor ( 7) connected to the non-inverting input of the first amplifier (1) in the node with the first capacitor (9) connected to the common conductor, then the fourth resistor (8), while the non-inverting input of the second amplifier (2) is connected to the amplitude control circuit (12) connected to a common conductor.