CN205283499U - Power amplification control circuit - Google Patents

Abstract

The utility model discloses a power amplification control circuit, including resistance R1, electric capacity C1, triode VT1, diode D1 and triode VT2, resistance R1 one end is connecting resistance R2 respectively, incoming signal vi and triode VT1 base, electric capacity C1 is connected respectively to the resistance R1 other end, triode VT2 projecting pole, triode VT3 projecting pole and output vo, electric capacity C2 is connected respectively to triode VT3 collecting electrode, resistance R3 and the resistance R2 other end and ground connection, the electric capacity C2 other end and triode VT1 projecting pole are connected respectively to the resistance R3 other end, diode D1 negative pole is connected respectively to triode VT1 collecting electrode, electric capacity C4 and triode VT3 base. The utility model discloses power amplification control circuit does not adopt the fortune to put as the controller, and circuit structure is simple, and is with low costs, small, no matter is to the direct current or exchanges and to play very big power amplification effect that application scope is wide.

Description

A kind of power amplification control circuit

Technical field

This utility model relates to a kind of control circuit, specifically a kind of power amplification control circuit.

Background technology

Power amplifier is called for short power amplifier, refers to when given distortion rate, can produce maximum power output to drive the amplifier of load, and power amplifier application in household electrical appliances, digital product serves pivotal role, with our daily life close relation.

Power amplifier is the important component part in mobile phone wireless transmitter, in the front stage circuits of mobile phone wireless transmitter, produced by modulation oscillator circuit, RF signal power is only small, need through a series of amplification buffer stage, interstage amplifier section, final power amplifier stage, after obtaining enough radio-frequency powers, it radiate just can be fed on antenna, in order to obtain sufficiently large radio frequency power output, it is necessary to adopt rf power amplifier circuit.

But traditional power amplification circuit also exists following deficiency when processing small-signal: (1) designs the amplifier feed-back resistance of bigger resistance to obtain bigger input resistance and amplification, and the feedback resistance of bigger resistance can produce the bigger drift temperature difference; (2) cannot be carried out effective amplitude limit, the signal power of input Vi input is excessive, and amplifier is fragile; (3) circuit structure is complicated, and volume is big, and cost is high.

Utility model content

The purpose of this utility model is in that to provide a kind of power amplification control circuit, with the problem solving to propose in above-mentioned background technology.

For achieving the above object, this utility model provides following technical scheme:

A kind of power amplification control circuit, including resistance R1, electric capacity C1, audion VT1, diode D1 and audion VT2, described resistance R1 one end connects resistance R2 respectively, input signal Vi and audion VT1 base stage, the resistance R1 other end connects electric capacity C1 respectively, audion VT2 emitter stage, audion VT3 emitter stage and output end vo, audion VT3 colelctor electrode connects electric capacity C2 respectively, resistance R3 and the resistance R2 other end ground connection, the resistance R3 other end connects the electric capacity C2 other end and audion VT1 emitter stage respectively, audion VT1 colelctor electrode connects diode D1 negative pole respectively, electric capacity C4 and audion VT3 base stage, diode D1 positive pole connects resistance R5, the resistance R5 other end connects resistance R4 respectively, the electric capacity C4 other end and audion VT2 base stage, the resistance R4 other end connects the electric capacity C1 other end and resistance R6 respectively, the resistance R6 other end is connecting triode VT2 colelctor electrode and power supply VCC respectively.

As this utility model further scheme: described power supply VCC voltage is 5V.

Compared with prior art, the beneficial effects of the utility model are: this utility model power amplification control circuit does not adopt amplifier as controller, and circuit structure is simple, cost is low, volume is little, no matter is can both play very big power amplification effect for direct current or exchange, applied widely.

Accompanying drawing explanation

Fig. 1 is the circuit diagram of power amplification control circuit.

Detailed description of the invention

Below in conjunction with the accompanying drawing in this utility model embodiment, the technical scheme in this utility model embodiment is clearly and completely described, it is clear that described embodiment is only a part of embodiment of this utility model, rather than whole embodiments. Based on the embodiment in this utility model, the every other embodiment that those of ordinary skill in the art obtain under not making creative work premise, broadly fall into the scope of this utility model protection.

Refer to Fig. 1, in this utility model embodiment, a kind of power amplification control circuit, including resistance R1, electric capacity C1, audion VT1, diode D1 and audion VT2, described resistance R1 one end connects resistance R2 respectively, input signal Vi and audion VT1 base stage, the resistance R1 other end connects electric capacity C1 respectively, audion VT2 emitter stage, audion VT3 emitter stage and output end vo, audion VT3 colelctor electrode connects electric capacity C2 respectively, resistance R3 and the resistance R2 other end ground connection, the resistance R3 other end connects the electric capacity C2 other end and audion VT1 emitter stage respectively, audion VT1 colelctor electrode connects diode D1 negative pole respectively, electric capacity C4 and audion VT3 base stage, diode D1 positive pole connects resistance R5, the resistance R5 other end connects resistance R4 respectively, the electric capacity C4 other end and audion VT2 base stage, the resistance R4 other end connects the electric capacity C1 other end and resistance R6 respectively, the resistance R6 other end is connecting triode VT2 colelctor electrode and power supply VCC respectively, described power supply VCC voltage is 5V.

Operation principle of the present utility model is: refer to Fig. 1, (1) when inputting signal Vi and being direct current signal, after power supply VCC connects, audion VT1, VT2 and VT3 are not what simultaneously turn on, first power supply VCC provides base current to make VT2 turn on through R6, R4 for VT2, after VT2 conducting, its emitter current one tunnel provides base current to make VT1 turn on through R1 for VT1, after VT1 conducting, the base current of VT3 could be turned on to ground by the C-E pole of VT1, R3, so that VT3 conducting, the direct current signal that output end vo output is amplified.

(2) when inputting signal Vi and being AC signal, AC signal delivers to VT1 base stage, export from colelctor electrode after amplification, owing to colelctor electrode and base stage are inverted relationships, so the signal of VT1 colelctor electrode output and base signal opposite polarity, when the positive half-cycle signal of Vi is after VT1 amplifies, negative half-cycle signal is become from colelctor electrode output, this signal makes A point voltage decline, and after D1 and R5, B point voltage also declines, VT2 ends, A point voltage decline can make VT3 conducting deep, enters normal magnifying state, has the electric current of amplification to export from output end vo; The negative half-cycle signal flow process of Vi is similar with above-mentioned flow process, so, when the positive-negative half-cycle signal of Vi adds circuit, VT2 and VT3 alternation, there is the signal of complete amplification to export from output end vo.

It is obvious to a person skilled in the art that this utility model is not limited to the details of above-mentioned one exemplary embodiment, and when without departing substantially from spirit of the present utility model or basic feature, it is possible to realize this utility model in other specific forms. Therefore, no matter from which point, embodiment all should be regarded as exemplary, and be nonrestrictive, scope of the present utility model is limited by claims rather than described above, it is intended that all changes in the implication of the equivalency dropping on claim and scope included in this utility model. Any accompanying drawing labelling in claim should be considered as the claim that restriction is involved.

In addition, it is to be understood that, although this specification is been described by according to embodiment, but not each embodiment only comprises an independent technical scheme, this narrating mode of description is only for clarity sake, description should be made as a whole by those skilled in the art, and the technical scheme in each embodiment through appropriately combined, can also form other embodiments that it will be appreciated by those skilled in the art that.

Claims (2)

1. a power amplification control circuit, including resistance R1, electric capacity C1, audion VT1, diode D1 and audion VT2, it is characterized in that, described resistance R1 one end connects resistance R2 respectively, input signal Vi and audion VT1 base stage, the resistance R1 other end connects electric capacity C1 respectively, audion VT2 emitter stage, audion VT3 emitter stage and output end vo, audion VT3 colelctor electrode connects electric capacity C2 respectively, resistance R3 and the resistance R2 other end ground connection, the resistance R3 other end connects the electric capacity C2 other end and audion VT1 emitter stage respectively, audion VT1 colelctor electrode connects diode D1 negative pole respectively, electric capacity C4 and audion VT3 base stage, diode D1 positive pole connects resistance R5, the resistance R5 other end connects resistance R4 respectively, the electric capacity C4 other end and audion VT2 base stage, the resistance R4 other end connects the electric capacity C1 other end and resistance R6 respectively, the resistance R6 other end is connecting triode VT2 colelctor electrode and power supply VCC respectively.

2. power amplification control circuit according to claim 1, it is characterised in that described power supply VCC voltage is 5V.