CN212907054U

CN212907054U - Circuit for realizing progressive playing of sound

Info

Publication number: CN212907054U
Application number: CN202021652129.8U
Authority: CN
Inventors: 姚超; 郑继清
Original assignee: Chengdu Create Automotive Electronics Co ltd
Current assignee: Chengdu Create Automotive Electronics Co ltd
Priority date: 2020-08-10
Filing date: 2020-08-10
Publication date: 2021-04-06
Anticipated expiration: 2030-08-10

Abstract

The utility model discloses a circuit of sound progressive play realizes, including sound player, triode Q1 and triode Q2, triode Q1's base connect first signal input part, triode Q1's projecting pole ground connection, triode Q1's collecting electrode is connected to triode Q3's base through resistance R3, standard voltage is connected to triode Q3's projecting pole, and triode Q3's collecting electrode is connected to the positive pole that sound player, and sound player's negative pole is connected to triode Q2's collecting electrode, triode Q2's base is connected to second signal input part, triode Q3's collecting electrode still is through electric capacity C1 ground connection. The utility model has the advantages that design electric capacity C1, when the power just started, the power need charge electric capacity C1, then the sound is put on the ware voltage and can slowly grow, sound also can slowly grow gradually, and behind the power disconnection, electric capacity C1 discharges, then the sound is put on the ware voltage and can slowly diminish, sound also can gradually slowly diminish, realize through electric capacity C1 that the cost is very low.

Description

Circuit for realizing progressive playing of sound

Technical Field

The utility model relates to a broadcast circuit, concretely relates to circuit that realizes sound broadcast that advances one by one.

Background

The buzzer is an electronic buzzer with an integrated structure, adopts direct current voltage for power supply, and is widely applied to electronic products such as computers, printers, copiers, alarms, electronic toys, automobile electronic equipment, telephones, timers and the like as a sounding device.

In the sound production of the existing buzzer, progressive sound production is often adopted to produce an audible sound, but the existing circuit often changes the voltage loaded on the buzzer, and the loaded voltage is controlled by a PWM (pulse width modulation) chip to adjust the sound production of the buzzer, but the cost of the PWM chip is too high.

SUMMERY OF THE UTILITY MODEL

It is an object of the present invention to solve at least the above problems and to provide at least the advantages which will be described later.

An object of the utility model is to provide a circuit of broadcast is advanced to realization sound sends progressive sound through PWM modulation chip control for solving current bee calling organ, has the defect of cost too high.

To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, there is provided a circuit for realizing progressive playing of sound, comprising a sound emitter, a transistor Q1 and a transistor Q2, wherein a base of the transistor Q1 is connected to a first signal input terminal, an emitter of the transistor Q1 is grounded, a collector of the transistor Q1 is connected to a base of the transistor Q3 through a resistor R3, an emitter of the transistor Q3 is connected to a standard voltage, a collector of the transistor Q3 is connected to an anode of the sound emitter, a cathode of the sound emitter is connected to a collector of the transistor Q2, a base of the transistor Q2 is connected to a second signal input terminal, an emitter of the transistor Q2 is grounded, a collector of the transistor Q3 is further grounded through a capacitor C1, the transistors Q1 and Q2 are NPN transistors, and the transistor Q3 is.

In the circuit, the capacitor C1 is designed, when the standard voltage is loaded on the sound player, the capacitor C1 is charged, the voltage on the sound player is slowly increased, so that the gradually increased sound is generated, after the sound player is not connected with the standard voltage, the capacitor C1 discharges the sound player again, the voltage on the capacitor C1 is slowly reduced, and the voltage on the sound player is slowly reduced, so that the gradually decreased sound is generated.

In one possible design, a resistor R5 is connected in parallel to the amplifier. The device is used for shunting the sound amplifier and protecting the sound amplifier.

In one possible design, a resistor R1 is provided between the first signal input and the base of transistor Q1. The signal source is prevented from being overloaded, the current of the signal source is converted into voltage output, and voltage drop is generated on the resistor R1.

In one possible design, the base of the transistor Q1 is also connected to ground via a resistor R2. The signal source of the first signal input end is grounded through the resistor R1 and the resistor R2, so that the voltage at the base electrode of the triode Q1 is the voltage on the resistor R2, the phenomenon that the triode Q1 generates misoperation under the influence of noise signals is prevented, and the transistor is cut off more reliably.

In one possible design, a resistor R6 is provided between the second signal input and the base of transistor Q2. This arrangement is consistent with the above arrangement and prevents overloading of the signal source, converting the current from the signal source to a voltage output, producing a voltage drop across resistor R6.

In one possible design, the base of the transistor Q2 is also connected to ground via R7. The signal source of the second signal input end is grounded through the resistor R6 and the resistor R7, so that the voltage at the base electrode of the triode Q2 is the voltage on the resistor R6, the phenomenon that the triode Q2 generates misoperation under the influence of noise signals is prevented, and the transistor is cut off more reliably.

In one possible design, the capacitor C1 has one end connected to the collector of the transistor Q3 and the other end connected to ground via the resistor R4. At the moment that the standard voltage is switched on the capacitor C1, the capacitor C1 is regarded as a short circuit, if no R4 exists, the power supply is directly grounded, and the resistor R4 is arranged, so that the phenomenon that the power supply is grounded is avoided.

The utility model discloses at least, include following beneficial effect: (1) the capacitor C1 is designed, when the power supply is just started, the power supply needs to charge the capacitor C1, the voltage on the sound amplifier will gradually increase, and the sound will gradually increase, and after the power supply is disconnected, the capacitor C1 discharges, the voltage on the sound amplifier will gradually decrease, and the sound will gradually decrease, and the cost is very low through the capacitor C1;

(2) the switching is controlled by the triode Q1 and the triode Q3, and the PNP triode Q3 is added because the NPN triode Q1 cannot completely cut off the circuit;

(3) and designing a second signal input end, inputting square waves and controlling the playing of the passive audio amplifier.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Drawings

Fig. 1 is a circuit diagram of the present invention.

Detailed Description

The invention will be further described with reference to the accompanying drawings and specific embodiments. It should be noted that the description of the embodiments is provided to help understanding of the present invention, but the present invention is not limited to the description. Specific structural and functional details disclosed herein are merely illustrative of example embodiments of the invention. The present invention may, however, be embodied in many alternate forms and should not be construed as limited to the embodiments set forth herein.

It is to be noted that the experimental methods described in the following embodiments are all conventional methods unless otherwise specified, and the reagents and materials, if not otherwise specified, are commercially available; in the description of the present invention, the terms "lateral", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

As shown in fig. 1, a circuit for realizing progressive playing of sound includes an audio amplifier, a transistor Q1 and a transistor Q2, wherein a base of the transistor Q1 is connected to a first signal input terminal, an emitter of the transistor Q1 is grounded, a collector of the transistor Q1 is connected to a base of the transistor Q3 via a resistor R3, an emitter of the transistor Q3 is connected to a standard voltage, a collector of the transistor Q3 is connected to an anode of the audio amplifier, a cathode of the audio amplifier is connected to a collector of the transistor Q2, a base of the transistor Q2 is connected to a second signal input terminal, an emitter of the transistor Q2 is grounded, a collector of the transistor Q3 is also grounded via a capacitor C1, the transistor Q1 and the transistor Q2 are NPN transistors, and the transistor Q3 is a PNP transistor.

The first signal source is transmitted by the first signal input end, after the base of the triode Q1 is electrified, the collector and the emitter of the triode Q1 are communicated, the base of the triode Q3 is grounded, the triode Q3 is conducted, if no signal exists at the second signal input end, the triode Q2 is not conducted, at this time, the capacitor C1 is electrified, but the sound amplifier does not form a loop and cannot generate the sound, after the second signal input end transmits the signal, the triode Q2 is conducted, the sound amplifier only plays monotone sound, so that the second signal source is required to be simultaneously input, when the triode Q35 3 is conducted, the triode Q2 is also conducted, the sound amplifier is grounded, at this time, the sound of the sound amplifier is small when the sound amplifier starts due to the charging of the capacitor C1, and the sound of the sound amplifier is slowly increased in. And the second signal source entering the second signal input should be a square wave, since the sound amplifier is passive and needs an oscillating square wave to be able to sound.

When the power is cut off, the signal of the first signal input end is disconnected, the base of the triode Q1 is grounded, the collector and the emitter are disconnected, the base of the triode Q3 is disconnected, the triode Q3 is cut off, at the moment, the C1 discharges electricity, the sound player can play sound, meanwhile, the second signal source is not disconnected, and the sound player emits gradually-reduced sound until the capacitor C1 discharges completely.

While the embodiments of the invention have been described above, it is not intended to be limited to the details shown, or described, but rather to cover all modifications, which would come within the scope of the appended claims, and all changes which come within the meaning and range of equivalency of the art are therefore intended to be embraced therein.

Claims

1. A circuit for realizing sound progressive playing is characterized by comprising a sound amplifier, a triode Q1 and a triode Q2, wherein the base of the triode Q1 is connected with a first signal input end, the emitter of the triode Q1 is grounded, the collector of the triode Q1 is connected to the base of the triode Q3 through a resistor R3, the emitter of the triode Q3 is connected with standard voltage, the collector of the triode Q3 is connected to the positive electrode of the sound amplifier, the negative electrode of the sound amplifier is connected to the collector of the triode Q2, the base of the triode Q2 is connected to a second signal input end, the emitter of the triode Q2 is grounded, the collector of the triode Q3 is further grounded through a capacitor C1, the triode Q1 and the triode Q2 are NPN triodes, and the triode Q3 is a PNP triode.

2. The circuit of claim 1 wherein a resistor R5 is connected in parallel across the amplifier.

3. The circuit of claim 1, wherein a resistor R1 is disposed between the first signal input and the base of transistor Q1.

4. The circuit of claim 3, wherein the base of transistor Q1 is further coupled to ground via a resistor R2.

5. The circuit of claim 1, wherein a resistor R6 is disposed between the second signal input and the base of transistor Q2.

6. The circuit of claim 1, wherein the base of transistor Q2 is further coupled to ground via R7.

7. The circuit as claimed in claim 1, wherein the capacitor C1 has one end connected to the collector of the transistor Q3 and the other end connected to ground via a resistor R4.