CN214591941U

CN214591941U - Standby starting circuit

Info

Publication number: CN214591941U
Application number: CN202120772012.1U
Authority: CN
Inventors: 刘运林
Original assignee: Dongguan Tingfeng Electronic Co ltd
Current assignee: Dongguan Tingfeng Electronic Co ltd
Priority date: 2021-04-15
Filing date: 2021-04-15
Publication date: 2021-11-02
Anticipated expiration: 2031-04-15

Abstract

The utility model relates to a wireless stereo technical field relates to a standby starting circuit. It includes: the device comprises a comparator U2, a reference voltage circuit, a switch SW, -12V negative voltage power supply, an amplifying circuit, a rectifying circuit and an audio signal receiving end; the 12V power supply is connected with the non-inverting input terminal of the comparator U2 through a reference voltage circuit, and the 12V power supply is connected with the inverting input terminal of the comparator U2 through a switch SW; the output end of the comparator U2 supplies power to the outside; the audio signal receiving end is connected with the amplifying circuit, the rectifying circuit and the inverting input end of the comparator U2 in sequence. The utility model discloses a switch SW selects mode, and standby starting circuit both can start through audio signal, can directly start convenient to use through switch SW again.

Description

Standby starting circuit

Technical Field

The utility model relates to a wireless stereo technical field relates to a standby starting circuit.

Background

When a loudspeaker of the wireless sound box works, the wireless sound box needs to receive audio signals and be connected with a power supply, and when the loudspeaker is used, the wireless sound box is not used all the time, especially when programs are spared, the loudspeaker is only used during drilling, and is not used in most of the time; at present, lithium batteries are generally adopted in wireless sound equipment, so that a lot of wireless sound equipment use a standby technology and are controlled by a standby circuit; the existing standby circuit can be started only by audio input when in standby, cannot be started by a switch, and can be started again only after the switch is turned off; it cannot be started directly from standby; bringing inconvenience to the use.

Disclosure of Invention

An object of the utility model is to provide a not enough to prior art, provide a standby starting circuit, this standby starting circuit both can start through audio signal, also can switch to switch start, convenient to use.

A standby startup circuit, comprising: the device comprises a comparator U2, a reference voltage circuit, a switch SW, -12V negative voltage power supply, an amplifying circuit, a rectifying circuit and an audio signal receiving end;

the 12V power supply is connected with the non-inverting input terminal of the comparator U2 through a reference voltage circuit, and the 12V power supply is connected with the inverting input terminal of the comparator U2 through a switch SW; the output end of the comparator U2 supplies power to the outside; the audio signal receiving end is connected with the amplifying circuit, the rectifying circuit and the inverting input end of the comparator U2 in sequence.

Furthermore, the reference voltage circuit comprises a resistor R10, a resistor R11, a resistor R12 and a reference voltage comparator U11, wherein the input end of the resistor R10 is connected with a negative voltage power supply of-12V through a resistor R9, and the resistor R10 and the resistor R11 are connected in series and then connected with the non-inverting input end of the comparator U2 through a resistor R13; the input end and the output end of the resistor R10 are respectively connected with two input ends of a reference voltage comparator U11, and the output end of the reference voltage comparator U11 is connected with the output end of the resistor R11 through the resistor R12.

Further, the output terminal of the comparator U2 is connected to the non-inverting input terminal of the comparator U2 through a resistor R14.

Further, a filter circuit is connected to an inverting input terminal of the comparator U2, and the filter circuit includes a capacitor C1 and a resistor R7 connected in parallel.

Further, the inverting input of the comparator U2 is connected to ground through a diode D2.

Further, the rectifying circuit comprises a diode D1 connected in reverse, the cathode of the diode D1 is connected with the output end of the amplifying circuit, and the anode of the diode D1 is connected with the inverting input end of the comparator U2 through a resistor R5.

Further, the cathode of the diode D1 is grounded through a capacitor C5.

Further, the amplifying circuit comprises an operational amplifier U1, and the non-inverting input terminal of the operational amplifier U1 is grounded; a capacitor C4, a resistor R4 and a reversely connected diode ZD1 which are connected in parallel are connected between the inverting input end and the output end of the operational amplifier U1, the inverting input end of the operational amplifier U1 is connected with the right audio receiving end of the audio signal receiving end sequentially through a capacitor C1 and a resistor R1, and the inverting input end of the operational amplifier U1 is connected with the left audio receiving end of the audio signal receiving end sequentially through a capacitor C2 and a resistor R2.

The utility model has the advantages that: the utility model discloses a switch SW selects mode, and standby starting circuit both can start through audio signal, can directly start convenient to use through switch SW again.

Drawings

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

Detailed Description

The following detailed description of the present invention is made with reference to the accompanying drawings. As shown in fig. 1.

Example 1: a standby startup circuit, comprising: the device comprises a comparator U2, a reference voltage circuit, a switch SW, -12V negative voltage power supply, an amplifying circuit, a rectifying circuit and an audio signal receiving end;

When the technical scheme works, the working mode is selected by the switch SW; 1, when the switch is on, the-12V negative voltage of the-12V negative voltage power supply is directly loaded on the inverting input end of the comparator U2, and the-12V negative voltage power supply outputs a reference voltage after passing through a reference voltage circuit, wherein the reference voltage is negative and is more than-12V; therefore, the non-inverting input terminal of the comparator U2 is higher than the voltage of the inverting input terminal, and the comparator U2 outputs a high level to the outside, thereby starting the circuit. 2. When the switch is open, the-12V negative voltage power supply cannot provide negative voltage to the inverting input terminal of the comparator U2. 2.1: if no audio signal exists at this time, the voltage at the inverting input terminal of the comparator U2 is not provided, that is, 0, and the voltage at the non-inverting input terminal of the comparator U2 has a reference voltage of negative voltage, so that the voltage at the non-inverting input terminal is lower than that at the inverting input terminal, the comparator U2 outputs a low level or does not output the low level to the outside; the circuit cannot be started. 2.2: if the audio signal with negative pressure is input at the moment, the negative pressure of the audio signal is amplified and rectified to provide starting negative pressure for the inverting input end of the comparator U2; at the moment, the negative pressure of the audio signal is required to reach a certain value, namely, a real audio signal is required to be input, but not noise; so that the starting negative voltage is lower than the negative voltage of the reference voltage, the output end of the comparator U2 outputs high level to the outside, and other circuits are started. During design, the amplifying circuit amplifies the lowest-voltage audio signal negative pressure, and the amplifying circuit is adjusted to enable the amplified negative pressure to meet the requirements.

Therefore, the technical scheme selects the starting mode of the standby starting circuit through the switch SW; the switch SW selects the working mode 2, and the standby starting circuit does not output high level outwards any more under the condition of no audio input; when an audio signal is input, the standby starting circuit outputs high voltage to the outside. The mode is switched to the working mode 1 by the switch SW, and the standby starting circuit immediately outputs high level, namely, the standby starting circuit is directly started by the switch SW.

The reference voltage circuit mainly comprises a resistor R10, a resistor R11, a resistor R12 and a reference voltage comparator U11, wherein the reference value U is (R12/R12 + R11) (-2.5) ≈ 0.387V.

Resistor R14 is a positive feedback for adjusting the output of the reference voltage circuit.

And an RC filter circuit is arranged to filter the voltage input by the inverting input end of the comparator U2 and remove background noise.

The diode D2 prevents the reverse connection of the previous lines, resulting in a positive voltage at the inverting input of the input comparator U2.

The diode D1 rectifies the amplified voltage of the audio signal voltage to remove the positive voltage.

Further, the cathode of the diode D1 is grounded through a capacitor C5.

The capacitor C5 acts as a filter to remove background noise.

The negative pressure of the audio signal is amplified by the operational amplifier U1. The capacitor C1 and the resistor R1 form an RC filter circuit to filter the input right audio signal, and similarly, the capacitor C2 and the resistor R2 form an RC filter circuit to filter the input left audio signal.

The above description is only a preferred embodiment of the present invention, and for those skilled in the art, there are variations on the detailed description and the application scope according to the idea of the present invention, and the content of the present description should not be interpreted as a limitation to the present invention.

Claims

1. A standby startup circuit, characterized by: it includes: the device comprises a comparator U2, a reference voltage circuit, a switch SW, -12V negative voltage power supply, an amplifying circuit, a rectifying circuit and an audio signal receiving end;

2. A standby power up circuit according to claim 1, wherein: the reference voltage circuit comprises a resistor R10, a resistor R11, a resistor R12 and a reference voltage comparator U11, wherein the input end of the resistor R10 is connected with a negative voltage power supply of-12V through a resistor R9, and the resistor R10 and the resistor R11 are connected in series and then connected with the non-inverting input end of the comparator U2 through a resistor R13; the input end and the output end of the resistor R10 are respectively connected with two input ends of a reference voltage comparator U11, and the output end of the reference voltage comparator U11 is connected with the output end of the resistor R11 through the resistor R12.

3. A standby power up circuit according to claim 2, wherein: the output terminal of the comparator U2 is connected to the non-inverting input terminal of the comparator U2 through a resistor R14.

4. A standby power up circuit according to claim 3, wherein: and the inverting input end of the comparator U2 is connected with a filter circuit, and the filter circuit comprises a capacitor C1 and a resistor R7 which are connected in parallel.

5. A standby power up circuit according to claim 4, wherein: the inverting input of comparator U2 is connected to ground through diode D2.

6. A standby power up circuit according to claim 5, wherein: the rectifying circuit comprises a diode D1 connected in reverse, the cathode of a diode D1 is connected with the output end of the amplifying circuit, and the anode of a diode D1 is connected with the inverting input end of a comparator U2 through a resistor R5.

7. A standby power up circuit according to claim 6, wherein: the cathode of the diode D1 is connected to ground through a capacitor C5.

8. A standby power up circuit according to claim 1, wherein: the amplifying circuit comprises an operational amplifier U1, and the non-inverting input end of the operational amplifier U1 is grounded; a capacitor C4, a resistor R4 and a reversely connected diode ZD1 which are connected in parallel are connected between the inverting input end and the output end of the operational amplifier U1, the inverting input end of the operational amplifier U1 is connected with the right audio receiving end of the audio signal receiving end sequentially through a capacitor C1 and a resistor R1, and the inverting input end of the operational amplifier U1 is connected with the left audio receiving end of the audio signal receiving end sequentially through a capacitor C2 and a resistor R2.