CN217804545U

CN217804545U - Sounding circuit applied to reversing radar

Info

Publication number: CN217804545U
Application number: CN202222090470.4U
Authority: CN
Inventors: 杨秀忠
Original assignee: Qingdao Jianbang Automobile Technology Co ltd
Current assignee: Qingdao Jianbang Automobile Technology Co ltd
Priority date: 2022-08-09
Filing date: 2022-08-09
Publication date: 2022-11-15
Anticipated expiration: 2032-08-09

Abstract

The utility model provides a be applied to sound production circuit of radar of backing a car, this sound production circuit is through the projecting pole of sending the PWM wave form to first triode, another base that first triode is connected to the pin that has the timer function, accomplish or operate in first triode, signal after the modulation separates the direct current back through first electric capacity, enlarge through second triode and third triode two-stage, send fourth triode power amplification back drive speaker sound production behind the RC filtering, because the speaker is the perception load, the electric current through the speaker is exactly the wave form of similar sine wave, sound effect is close with the analog signal drive, better tone quality has.

Description

Sound production circuit applied to reversing radar

Technical Field

The utility model relates to an electronic circuit technical field, in particular to be applied to sound production circuit of radar of backing a car.

Background

The reversing radar is an electronic device installed on an automobile, mainly detects the direction and distance of obstacles around the automobile body through ultrasonic waves, and prompts a driver through an audible alarm.

The existing automobile reversing radar system generally comprises four ultrasonic probes and a sounding unit, wherein the ultrasonic probes are respectively installed on front and rear bumpers of an automobile, and the sounding unit is arranged in a cab. The radar for back running of car is to emit ultrasonic wave with specific frequency to the periphery of car body, receive the return wave signal emitted from barrier by ultrasonic receiver, amplify the signal by return wave amplifier and send it to CPU for timely processing and analysis, and output the processed result to sound unit for alarm, so as to detect whether there is barrier around the car body and the concrete position relation between the barrier and the car body. The sounding unit sends out alarm prompt sound when the obstacle is detected.

In the prior art, the acoustic sound emitting unit usually adopts a buzzer or a special audio processing chip. However, with the buzzer, although the circuit point is simple and the control is easy, the sound is monotonous and harsh, and the sound quality is too poor. And the special audio processing chip is adopted, although the sound quality effect is excellent, the cost is extremely high, the utilization rate of chip resources is poor, and more resources are occupied.

SUMMERY OF THE UTILITY MODEL

The utility model discloses it is poor to aim at solving and adopt buzzer sound tone quality to and adopt pronunciation chip with high costs, the wasting of resources through utilizing singlechip function itself, adopts the separator to realize the sound production.

The utility model provides a sound production circuit applied to a reversing radar, which comprises a modulation part, an amplification part and a loudspeaker;

the modulation part comprises a first triode which is a PNP type triode; an emitter of the first triode is used for inputting PWM waveforms, a base of the first triode is connected with a timer, and a collector of the first triode is connected with the amplifying part;

the amplifying part comprises a first capacitor, a second triode, a third triode, a fourth triode and a diode; the second triode and the fourth triode are NPN type triodes, and the third triode is a PNP type triode; the base of the second triode is connected with the collector of the first triode, the base of the third triode is connected with the collector of the second triode, the base of the fourth triode is connected with the collector of the third triode, the collector of the fourth triode is connected with the cathode of the diode, and the anode of the diode is connected with the loudspeaker.

Furthermore, the amplifying part further comprises a first RC filter circuit, a ninth resistor and a second capacitor are connected in parallel with the first RC filter circuit, one end of the ninth resistor and one end of the second capacitor are connected with the collector of the third triode, and the other end of the ninth resistor and the other end of the second capacitor are grounded.

Furthermore, the amplifying part further comprises a second RC filter circuit, and the second RC filter circuit is connected in parallel with a tenth resistor and a third capacitor, one end of the tenth resistor and one end of the third capacitor are connected to the emitter of the fourth transistor, and the other end of the tenth resistor and the other end of the third capacitor are grounded.

The utility model discloses the beneficial effect who reaches is:

the utility model discloses be applied to the distance warning sound of radar and preceding radar of backing a car, only need several triodes and resistance-capacitance piece, do not need bee calling organ and pronunciation chip, send different prompt tone at the distance of difference, through the length change of frequency change and sound, produce different sense of pressing, only use two feet of singlechip, two timers just can produce different sounds.

Compared with a buzzer, the utility model has the advantages that the tone quality is greatly improved; meanwhile, the sound is easy to adjust, and different types of prompt tones can be emitted according to different conditions; and the circuit can be simplified under the condition of meeting the radar requirement, and the cost is reduced.

The utility model discloses signal after the modulation passes through electric capacity and separates the direct current, can protect the speaker not burnt out old time, and the enlargement portion is the complete disconnection to the speaker when not phonating, can protect the speaker, reduces the consumption.

Drawings

Fig. 1 is a topological diagram of a sounding circuit applied to a reversing radar provided by an embodiment of the present invention.

Detailed Description

The technical solution of the present invention will be described in more detail with reference to the accompanying drawings, and the present invention includes, but is not limited to, the following embodiments.

As shown in the attached figure 1, the utility model provides a be applied to sound production circuit of radar of backing a car includes modulation part, enlargeing part and speaker.

The modulation part comprises a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4 and a first triode Q1, wherein the first triode Q1 is a PNP type triode.

One end of a first resistor R1 is connected with a 5V level, the other end of the first resistor R1 is connected with a timer MCU1 and a second resistor R2, the other end of the second resistor R2 is connected with a base of a first triode Q1, an emitting electrode of the first triode Q1 is used for inputting PWM waveforms, a collector electrode of the first triode Q1 is respectively connected with a third resistor R3 and a fourth resistor R4, the other end of the third resistor R3 is grounded, and the other end of the fourth resistor R4 is connected with an amplifying part.

The amplifying part comprises a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a first RC filter circuit, a first capacitor C1, a second RC filter circuit, a second triode Q2, a third triode Q3, a fourth triode Q4 and a diode D14; the second triode Q2 and the fourth triode Q4 are NPN type triodes, and the third triode Q3 is a PNP type triode.

The input end of the amplifying part is connected with a first capacitor C1, the other end of the first capacitor C1 is respectively connected with bases of a fifth resistor R5 and a second triode Q2, the other end of the fifth resistor R5 is grounded, an emitting electrode of the second triode Q2 is grounded, a collecting electrode of the second triode Q2 is respectively connected with a sixth resistor R6 and a seventh resistor R7, the sixth resistor R6 is connected with a 5V level, the other end of the seventh resistor R7 is connected with a base electrode of a third triode Q3, an emitting electrode of the third triode Q3 is connected with a 5V level, a collecting electrode of the third triode Q3 is connected with a base electrode of a fourth triode Q4 through an eighth resistor R8 and a first RC filter circuit, an emitting electrode of the fourth triode Q4 is connected with a second RC filter circuit, a collecting electrode of the fourth triode Q4 is connected with a negative electrode of a diode D14, and a positive electrode of the diode D14 is connected with a loudspeaker.

The first RC filter circuit comprises a ninth resistor R9 and a second capacitor C2 which are connected in parallel, and the other ends of the ninth resistor R9 and the second capacitor C2 are grounded. The second RC filter circuit comprises a tenth resistor R10 and a third capacitor C3 which are connected in parallel, and the other ends of the tenth resistor R10 and the third capacitor C3 are grounded.

The loudspeaker has two input ends, one end is connected with the amplifying part, and the other end is connected with the 12V level.

The PWM waveform is generated by two pins of the singlechip and the timer and is output to the modulation part.

The utility model provides an emitter of triode Q1 is sent with the PWM waveform to generating circuit, another pin MCU1 that has the timer function, accomplish or (XOR) operation in Q1, the signal after the modulation passes through C1 and separates the direct current after, through Q2, the back is enlargied to Q3 two-stage, send Q4 power amplification back drive speaker sound production behind the RC filtering, because the speaker is the perceptual load, the electric current through the speaker is exactly similar sinusoidal wave form, the sound effect is close with the analog signal drive, better tone quality has. Meanwhile, the volume can be adjusted by utilizing the duty ratio of the PWM, the tone can be adjusted by utilizing the frequency of the PWM, and the tone and the sound interval can be adjusted by the MCU 1.

The present invention is not limited to the above embodiments, and those skilled in the art can adopt other embodiments to implement the present invention according to the disclosure of the embodiments and the drawings, so that all the designs and ideas of the present invention can be adopted to make some simple changes or modifications, and all fall into the protection scope of the present invention.

Claims

1. The sounding circuit applied to the reversing radar is characterized by comprising a modulation part, an amplification part and a loudspeaker;

the modulation part comprises a first triode which is a PNP type triode; an emitting electrode of the first triode is used for inputting PWM waveforms, a base electrode of the first triode is connected with a timer, and a collecting electrode of the first triode is connected with the amplifying part;

the amplifying part comprises a first capacitor, a second triode, a third triode, a fourth triode and a diode; the second triode and the fourth triode are NPN type triodes, and the third triode is a PNP type triode; the base of second triode with the collecting electrode of first triode is connected, the base of third triode with the collecting electrode of second triode is connected, the base of fourth triode with the collecting electrode of third triode is connected, the collecting electrode of fourth triode is connected the negative pole of diode, the positive pole of diode is connected the speaker.

2. The sounding circuit applied to the reverse sensor as claimed in claim 1, wherein the amplifying part further comprises a first RC filter circuit, the first RC filter circuit is connected with a ninth resistor and a second capacitor in parallel, one end of the ninth resistor and one end of the second capacitor are connected with the collector of the third transistor, and the other end of the ninth resistor and the second capacitor are grounded.

3. The sounding circuit applied to the reverse sensor of claim 1, wherein the amplifying part further comprises a second RC filter circuit, the second RC filter circuit is connected with a tenth resistor and a third capacitor in parallel, one end of the tenth resistor and one end of the third capacitor are connected with the emitter of the fourth triode, and the other end of the tenth resistor and the other end of the third capacitor are grounded.