JPH04131017U - High fidelity amplifier power supply - Google Patents

Abstract

(57) [Summary] [Purpose] Separate the power supply circuits to each amplification stage in a high-fidelity amplifier to eliminate the negative influence on sound quality caused by the power supply current. [Structure] A constant current circuit A having a current control transistor Q ₂ and a parallel control type constant voltage circuit B are connected in series to a terminal S that is supplied with power from the main power supply, and are connected in series to a terminal S that is supplied with power from the main power supply. By inserting constant voltage circuits C and D and supplying power to each amplifier stage separately, deterioration in fidelity due to currents in other amplifier stages is prevented.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is a high-fidelity amplification device used in audio amplifiers to perform high-fidelity amplification. The present invention relates to a power supply device for a width gauge.

0002

[Conventional technology]

Audio amplifiers use sound sources such as records, CDs, tuners, tapes, etc. Amplify the obtained microvoltage reproduction signal as faithfully as possible to drive the speaker. Care has been taken in its design to provide a high fidelity amplifier with high output power. .

0003 High-fidelity amplifiers not only have a wide frequency band, but also It is desired that cross-modulation between the width steps be almost completely eliminated.

0004 Figure 3 is a circuit diagram showing an example of an amplifier that attempts to perform such high-fidelity amplification. It is equipped with two power supplies, + and -, and uses npn and pnp transistors. This is a so-called symmetrical differential two-stage amplifier using two stages of rementary differential amplifier circuits.

[0005]The output from the first stage section consisting of transistors _Q1 to _Q4 (collector of _Q1 to _Q4 ) is the input to the second stage section consisting of transistors _Q5 to _Q8 (base of _Q5 to _Q8 ). The signals amplified by the first stage are transmitted to the second stage, where high-fidelity amplification is performed.

[0006]

[Problem that the idea aims to solve]

In the amplifier shown in Figure 3 above, when looking at the + side and - side power supplies, the first stage and second stage The part is a common control transistor Q controlled by a Zener diode ZD. ₁₁ and Q₁₂Power is supplied from. Each of these control outputs is connected to a capacitor. A power supply capacitor is inserted to decouple the power supply, but the Because the power supply is shared, they have a common impedance, and each amplification The stage currents influence each other through a common impedance, reducing the fidelity of the amplified signal. There is a risk that it may deteriorate.

[0007] This invention was devised in view of these problems, and its purpose is to increase high fidelity. Eliminate the common impedance of the amplifier stage power supply in the amplifier to obtain even higher fidelity. The object of the present invention is to provide a power supply device for a high-fidelity amplifier.

[0008]

[Means to solve the problem]

In order to achieve the above object, the present invention provides a multi-stage audio amplifier. In a power supply device for a high-fidelity amplifier that supplies power to an amplifier circuit, the above-mentioned multi-stage Provide multiple series-controlled constant voltage circuits that supply power to each amplifier circuit. At the same time, a constant current circuit and a constant current circuit are installed upstream of these constant voltage circuits to collectively supply power to these circuits. A power supply device for a high fidelity amplifier is provided that includes a control circuit in combination with a voltage circuit. .

[0009]

【Example】

Next, embodiments of the present invention will be described in detail using the drawings.

0010 Figure 1 is a basic circuit diagram showing an embodiment of a power supply device for a high-fidelity amplifier according to the present invention. 2 is a circuit diagram of an amplifier to which the basic circuit is applied.

[0011] Figure 1 is a basic circuit diagram showing an embodiment of a power supply device for a high-fidelity amplifier according to the present invention. 2 is a circuit diagram of an amplifier to which the basic circuit is applied.

In FIG. 1, A is a constant current circuit having transistors Q ₁ , Q ₂ , Q ₃ and a constant voltage diode ZD ₁ , and the voltage between the base of Q ₁ and the terminal S is maintained at the Zener voltage by ZD ₁ . On the other hand, a resistor R ₁ is inserted into the emitter, and the collector is connected to the base of Q ₂ for current control. Therefore, for example, the current flowing toward the load from the input terminal S of the power supply supplied from the power transformer via the rectifier, smoothing circuit, etc. becomes a constant current set by R ₁ and the Zener voltage of ZD ₁ . It is composed of Note that the FET (field effect transistor) _Q3 serves as a constant current element that stabilizes the operation of _ZD1 .

Next, B is a constant voltage circuit having transistors Q ₄ and ZD ₂ . ZD ₂ is connected between the collector and base of Q ₄ , and the potential of the base is suppressed by its Zener voltage. Therefore, even if the input side or output fluctuates, the collector current of _Q4 increases or decreases, and the circuit is configured as a parallel control type constant voltage circuit in which the output voltage, which is higher than the Zener voltage by V _BE , is held constant. There is.

Next, C and D are constant voltage circuits that supply power to multiple amplification stages of the amplifier, for example, individually supply power to a two-stage amplifier, and include transistors Q ₅ and Q ₆ , constant voltage diodes ZD ₃ and It is equipped with ZD ₄ . In these constant voltage circuits C and D, a constant voltage diode is connected to the base of each transistor and held at that Zener voltage, so the constant voltage is lowered by V _BE corresponding to the Zener voltage. This is what gives you the output.

In this embodiment configured in this way, for example, as shown in the figure, power is supplied from the emitter of Q ₅ to the first stage of the amplifier, and power is supplied from the emitter of Q ₆ to the second stage of the amplifier. Even if the current changes depending on the strength of the signal amplified in each amplification stage, the series-controlled transistors Q ₅ and Q ₆ are separate, and further upstream from point P in the figure is a constant voltage circuit B, a constant voltage circuit. Because of the current circuit A, the voltage at point P is stabilized, and the influence of current changes in other amplification stages is eliminated.

[0016] Figure 2 shows such a basic circuit as a symmetrically operated two-stage amplifier similar to the conventional amplifier described above. This is a circuit diagram applied to an amplifier, and is used as a power source for the first stage and second stage. Ru.

In FIG. 2, transistors Q ₁ to Q ₄ and Q ₅ to _{Q 8} are amplifying elements in the first stage and second stage as in FIG. Attach Qb to the + power supply side to the step section, place a constant voltage diode ZDa at the bases of these Qa and Qb, supply power through the constant current element Ta, and apply the Zener voltage to the bases of Qa and Qb. It is applied.

[0018] On the power supply side of these Qa and Qb, the constant voltage circuits B and B described in FIG. 1 are connected. and constant current circuit A are connected in series, and terminal S is connected through a specified rectifier circuit or smoothing circuit. It is connected to a DC power source.

[0019] On the other hand, on the − power supply side, Qd is installed in the first stage and Qc is installed in the second stage. Place ZDb in the base circuit to stabilize the base with its Zener voltage. The collector circuit is connected to one end via a constant current circuit A' and a constant voltage circuit B'. Power is supplied from the child S'. Note that this constant current circuit A' and constant voltage circuit B' are as described above. complementary to each transistor in constant current circuit A and constant voltage circuit B. Using each transistor with the characteristics of It was made by sea urchin.

[0020] In an amplifier configured in this way, the input signal in the first stage and second stage is The current consumption varies depending on the frequency and amplitude of the audio signal, but the series Control transistors are separate for each stage, and constant current circuit A ( Stable power is supplied to point P (point P') by A') and constant voltage circuit B (B') Because of this, the effects between the amplification stages are removed and the amplifier operates as a stable amplifier. become.

[0021] The present invention has been explained above with reference to the above-mentioned embodiments. For example, if a constant current circuit or constant voltage circuit is connected to a constant current circuit of another type or a constant voltage circuit of another type, Various modifications are possible, and these are not excluded from the scope of the present invention. It's not.

[0022]

[Effect of the idea]

According to the present invention as in the embodiments described above, the power supply of an amplifier equipped with a multi-stage amplifier circuit is improved. As a power source, a stable power source is configured from the main power source via a constant current circuit and a constant voltage circuit. After that, a series control transistor is installed in each amplifier stage to supply constant voltage power. Based on the current of other amplification stages due to the common impedance of the power supply as in the conventional example, The effect is that the negative influence on fidelity is removed.

[Brief explanation of drawings]

FIG. 1 is a basic circuit showing an embodiment of a power supply device for a high-fidelity amplifier according to the present invention.

FIG. 2 is a circuit diagram of an amplifier to which the basic circuit is applied.

FIG. 3 is a circuit diagram showing an example of a conventional high-fidelity amplifier.

[Explanation of symbols]

A... Constant current circuit B... Constant voltage circuit C, D... Constant voltage circuit

Claims (1)

[Scope of utility model registration request] In a power supply device for a high-fidelity amplifier that supplies power to a plurality of stages of amplifier circuits of an audio amplifier, a plurality of series-controlled constant voltage circuits are provided to supply power to each of the plurality of stages of amplifier circuits. A power supply device for a high-fidelity amplifier, characterized in that a control circuit that combines a constant current circuit and a constant voltage circuit that collectively supplies power to these constant voltage circuits is provided upstream of these constant voltage circuits.