CN204392178U - Series connection modified model inductance oscillator - Google Patents

Abstract

The utility model discloses a kind of series connection modified model inductance oscillator, it to be connected a controllable impedance near transistor base end at the capacitive branch of Hartley oscillator frequency-selective network.The utility model can in the impregnable situation of Oscillator feedback coefficient, starting of oscillation easier than common inductance connecting three point type, and it is good not to improve ordinary oscillator waveform, and high order harmonic component feedback is comparatively strong, the problem that wave distortion is larger.

Description

Series connection modified model inductance oscillator

Technical field:

The utility model relates to field of oscillators, especially relates to LC field of oscillators.

Background technology:

Existing ordinary inductor bikini oscillator is also called Ha Laite oscillator, and it is good not that it exists waveform, and high order harmonic component feedback is comparatively strong, the technical problem that wave distortion is larger.

Summary of the invention:

In order to overcome above-mentioned prior art, to there is waveform good not, and high order harmonic component feedback is comparatively strong, and the technical deficiency that wave distortion is larger, the utility model provides the series connection modified model inductance oscillator for addressing this problem.

The utility model solves the technical scheme that its technical problem adopts: at ordinary inductor bikini oscillator, and namely the capacitive branch of Hartley oscillator frequency-selective network to be connected a controllable impedance near transistor base end.

The beneficial effects of the utility model are: in the impregnable situation of Oscillator feedback coefficient, regulate the frequency of oscillation of oscillator easily, the waveform that effective improvement exists is good not, high order harmonic component feedback is stronger, the technical problem that wave distortion is larger, makes the utility model starting of oscillation easier than common inductance of three-point.

Below in conjunction with the drawings and specific embodiments, the utility model is described in further detail.

Accompanying drawing illustrates:

Fig. 1 is common inductance connecting three point type circuit theory schematic diagram

Fig. 2 is series connection modified model inductance pierce circuit principle schematic of the present utility model

The symbol description of main element

Q1 is transistor

B is the base stage of transistor Q1

C is the collector electrode of transistor Q1

E is the emitter of transistor Q1

Embodiment:

Now with reference to the accompanying drawings, circuit structure of the present utility model is explained in detail.

Fig. 1 is common inductance connecting three point type circuit theory schematic diagram.

Inductance connecting three point type belongs to feedback oscillator, be Hartley oscillator again, primarily of amplifier and feedback network composition, wherein amplifier normally does load with frequency-selective network, the frequency of oscillation of oscillator determines primarily of frequency-selective network, feedback network is positive feedback necessarily, otherwise oscillator cannot vibrate.

As shown in Figure 1, its amplifier forms primarily of the interlock circuit of transistor Q1, and feedback network is made up of inductance L 2, and frequency-selective network is made up of two inductance and an electric capacity, is namely made up of the inductance L 1 in Fig. 1, inductance L 2, electric capacity C4.The reactance of inductance L 1 is X1, and the reactance of inductance L 2 is X2, and the reactance of electric capacity C4 is X4, and the composing principle according to bikini oscillator is: the reactance X1 be connected with transistor Q1 emitter E pole, and X2 character is identical; And the character of the reactance X4 be not connected with transistor Q1 emitter E is contrary with X1, X2.

In tickler-coil oscillator, normally around on the skeleton of same band magnetic core, there is mutual inductance between them, represent with M in inductance.The frequency of oscillation of oscillator can use the resonance frequency approximate representation in loop, namely l in formula is the total inductance in loop, and L=L1+L2+2M, is analyzed by phase equilibrium, and the frequency of oscillation expression formula of oscillator is ${\mathrm{\ω}}_1=\sqrt{\frac{1}{\mathrm{LC}4+g_{\mathrm{ie}}(g_{\mathrm{oe}}+g_L^{\′})(L_1{L}_2-M^2)}}$ G ' L in formula represent all conductances in the circuit except transistor convert the collector electrode C pole of transistor Q1 and two ends, emitter E pole after total conductance.It is less that frequency of oscillation is similar to its deviation when representing by the resonance frequency in loop, and coil coupling is tighter, and deviation is less.

But due to the speciality of inductance connecting three point type perception, the feedback signal of existing common inductance connecting three point type takes from L2, it is high impedance to high order harmonic component, high order harmonic component can not be suppressed, high order harmonic component can be fed back to input, exports, cause waveform good not after amplifying, high order harmonic component feedback is comparatively strong, and wave distortion is larger.

Fig. 2 is series connection modified model inductance pierce circuit principle schematic of the present utility model.As shown in Figure 2, series connection modified model inductance oscillator have been connected a controllable impedance L3 at the capacitive branch of Hartley oscillator frequency-selective network, according to the composing principle of bikini oscillator, identical with reactance L1, L2 character that transistor Q1 emitter E pole is connected; And the character of reactance C4 and L3 be not connected with transistor Q1 emitter E pole is contrary with L1, L2.So total impedance property that can judge electric capacity C4 and L3 series arm is capacitive.

The natural resonance frequency of this series connection modified model oscillator is:

$f_0=\frac{1}{2\mathrm{\π}\sqrt{(L1+L2+L3+2M)C4}};$

Feedback factor wherein, M is the coefficient of mutual inductance between two parts inductance, U _ffor feedback voltage, U ₀for output voltage.

The frequency of oscillation of all series connection modified model inductance determines primarily of inductance L 3 and electric capacity C4, and changed the frequency of oscillation of oscillator by adjustment L3, feedback factor F is unaffected.

As preferred implementation of the present utility model, inductance L 3 gets Large Copacity, due to L3>>L1, and L3>>L2, the frequency of oscillation of all series connection modified model inductance determines primarily of inductance L 3 and electric capacity C4, changed the frequency of oscillation of oscillator by adjustment L3, feedback factor F is unaffected.

Because L3 value is larger, the connected factor between frequency-selective network and amplifier can be made to increase, increase the output voltage of oscillator and cause feedback voltage to increase, according to the starting condition for oscillation AF=U of the amplitude of feedback oscillator _f/ U _i>1, wherein U _ffor feedback voltage, U _ifor input voltage, the starting of oscillation easier than common inductance of three-point of series connection modified model inductance oscillator.

Because feedback signal mainly takes from L2, and L2 value is less, less to the impedance of high order harmonic component, high order harmonic component can be suppressed better, high order harmonic component can be fed back to input, exports and also correspondingly reduces after amplifying, thus series connection modified model inductance oscillator to improve ordinary oscillator waveform good not, high order harmonic component feedback is comparatively strong, the problem that wave distortion is larger.

Series connection modified model inductance oscillator mainly for be the improvement of frequency-selective network, to the not requirement of outward appearance, color and encapsulating material, can be square, circularly wait random appearance, can be different colours, any materials encapsulation.

In sum, although the utility model openly as above.The utility model person of ordinary skill in the field, when not departing from spirit and scope of the present utility model, should be used for a variety of modifications and variations.Therefore, protection range of the present utility model should be as the criterion depending on the scope person of defining of appending claims.

Claims (2)

1. to connect a modified model inductance oscillator, it is characterized in that: to connect a controllable impedance near transistor base end at the capacitive branch of Hartley oscillator frequency-selective network.

2. inductor oscillating device as claimed in claim 1, is characterized in that: described controllable impedance value is much larger than the inductance value of Ha Laite Oscillator feedback network.