CN213342686U - Differential constant-voltage audio output bus loudspeaker disconnection detection circuit - Google Patents
Differential constant-voltage audio output bus loudspeaker disconnection detection circuit Download PDFInfo
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- CN213342686U CN213342686U CN202022460906.5U CN202022460906U CN213342686U CN 213342686 U CN213342686 U CN 213342686U CN 202022460906 U CN202022460906 U CN 202022460906U CN 213342686 U CN213342686 U CN 213342686U
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Abstract
The utility model discloses a differential formula level pressure audio output bus speaker detection circuitry that falls to line, including broadcast audio power amplifier and n speakers, broadcast audio power amplifier passes through bus IN1 bus IN2 and connects the OUT1/OUT2 both ends of a speaker detection module that falls to line, and, parallelly connected a diagnostic resistance of 1M omega IN every speaker moreover for every speaker consumes 48 uA's direct current, n is for being greater than 0 natural number; wherein: the loudspeaker is connected with the loudspeaker disconnection detection module in parallel through the impedance matching audio transformer BY and the audio capacitor CY/capacitor CY'; the audio signal of the broadcast audio power amplifier is output IN a 110V constant voltage form, and DC48V direct current voltage is generated IN the audio signal, and the direct current voltage is respectively connected with a bus IN1 and a bus IN2 through two audio chokes; the differential amplifier circuit detects the "detected physical quantity" and the "amount of change in the detected physical quantity".
Description
Technical Field
The utility model belongs to the detection area that falls of communications facilities relates to a differential formula level pressure audio output bus speaker detection circuitry that falls to line.
Background
In the field of emergency broadcasting, a power amplifier of a broadcasting system is connected with a plurality of loudspeakers through 2 buses (called broadcasting buses), and the loudspeakers are connected in parallel on the broadcasting buses through impedance matching audio transformers; the audio signal of the power amplifier is output in a peak-to-peak 110V constant voltage mode, DC48V direct current voltage is generated in the power amplifier and is applied to a broadcasting bus through 2 audio chokes; the loudspeaker drop detection module is hung on a broadcast bus, the outlet of each module can be connected with a plurality of loudspeakers, whether the connected loudspeakers are on-line or not is monitored under normal conditions, and when 1 or a plurality of loudspeakers drop, the module can output a pulse signal which is subjected to optical isolation and has enough width through a T + \ T-port.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a: the utility model provides a differential formula level pressure audio output bus speaker detection circuitry that drops is provided, has solved the not enough of above-mentioned problem.
The utility model adopts the technical scheme as follows:
a differential constant-voltage audio output bus loudspeaker disconnection detection circuit comprises a broadcast audio power amplifier and n loudspeakers, wherein the broadcast audio power amplifier is connected with a loudspeaker disconnection detection module through a bus IN 1/a bus IN2, and n is a natural number larger than 0;
wherein: the loudspeaker is connected with an interface OUT 1/an interface OUT2 of the loudspeaker disconnection detection module in parallel through an impedance matching audio transformer BY and an audio capacitor CY/capacitor CY', and a 1M omega diagnosis resistor is connected in each loudspeaker in parallel; the audio signal of the broadcast audio power amplifier is output IN a 110V constant voltage form, and DC48V direct current voltage is generated IN the audio signal, and the direct current voltage is respectively connected with a bus IN1 and a bus IN2 through two audio chokes; the loudspeaker disconnection detection module comprises a voltage nonpolar electricity taking circuit, a self-adaptive differential amplification circuit and a sampling isolation circuit;
the adaptive differential is that when the detected physical quantity is different in the number of speakers connected in parallel with OUT1/OUT2 (for example, 1 to 30 speakers), the correct operation state (T1 is on) can be maintained and the variation of the physical quantity can be accurately detected. Because the base of T1 obtains 100% of the detected physical quantity Vi, and the base of T2 obtains 97% of the detected physical quantity Vi' due to the partial pressure of RJ1\ RJ 2; and Vi can be changed following the change of the number of speaker lines, whereas Vi' can only be changed slowly due to the large capacitance CJ2, with a time constant of about (RJ9+ RC1) × CJ 2;
the voltage nonpolar electricity taking circuit obtains a working power supply from a bus IN 1/a bus IN2 and supplies power to the differential amplification circuit and the sampling isolation circuit; normally, an audio bypass capacitor (such as CC1) should be added to DU1 of R1-DU1-R2 in the sampling circuit, but since the output of DU1 is provided with a large-capacity filter capacitor, and the capacitive reactance of the filter capacitor is far less than that of R1+ R2, the audio bypass capacitor of DU1 can be eliminated, thereby saving the cost and improving the reliability.
The sampling isolation circuit collects sampling currents nI of n loudspeakers and outputs the sampling currents nI to a base stage of a triode T1/triode T2 through the output end of an isolation optocoupler UC 1; a resistor RJ9 is connected in series on a connecting circuit from the output end of the isolation optocoupler UC1 to the base stage of the triode T2, one end of a resistor RC2 is connected between the output end of the isolation optocoupler UC1 and the resistor RJ9, the other end of the resistor RC2 is grounded, and the resistor RC2 forms a sampling current nI into a voltage signal Vi for monitoring; one end of a resistor RC10 is connected between the resistor RJ9 and the base level of the triode T2, and the other end of the resistor RC10 is grounded;
the specific principle is as follows: the sampling isolation circuit comprises a capacitor CC1\ a bridge circuit DC1\ an isolation optocoupler UC1\ a resistor RC1\ a resistor RC2, collects sampling currents nI of n loudspeakers, and outputs the sampling currents nI to an RC2 through the output end of an isolation optocoupler UC 1; this is the physical quantity Vi to be detected; vi is directly input to a T1 base through RJ6 on one hand, and is attenuated through partial pressure of RJ9-RJ10 on the other hand and is input to a T2 base through stability of CJ 2; thus, the base of T1 can follow the change of Vi quickly, while the base of T2 can follow the change of Vi only slowly; the isolation optocoupler UC1 enables the ground of the detection circuit of the module to float, is only related to the position where R1\ R2 is connected into IN1\ IN2, really realizes 'single-point floating' to ensure the reliability of the detection circuit, and is added with the U2 photoelectric isolation output, so that the module realizes complete sampling, detection and output isolation; the lower level application restrictions can be relaxed to the maximum extent.
The adaptive differential amplifying circuit comprises a transistor T1 and a transistor T2, wherein an input voltage signal Vi is divided by a resistor RJ9 and a resistor RJ10, an actual output voltage signal is Vi ', and when Vi' < Vi: the output level VC2 is more than VC1, the triode T1 is conducted, and the output optocoupler U2 has no output; and when Vi' is greater than Vi: the output level VC2 is less than VC1, the triode T2 is conducted, and the output end of the output optocoupler U2 is conducted.
Further, the voltage nonpolar electricity taking circuit comprises a bridge circuit DU1, wherein a first alternating current input end of the bridge circuit DU1 is connected with a bus IN1 through a resistor R1, a second alternating current input end of the bridge circuit DU 3832 is connected with a bus IN2 through a resistor R2, a first direct current output end of the bridge circuit DU1 is grounded, and a second direct current output end of the bridge circuit DU1 is grounded through a capacitor C1.
Further, the sampling isolation circuit comprises a capacitor CC1, one end of the capacitor CC1 is connected IN parallel with the first ac input end of the DCI bridge circuit, and the other end of the capacitor CC1 is connected IN parallel with the second ac input end of the DCI bridge circuit and the bus IN 2; the first direct current output end and the second direct current output end of the bridge circuit DCI are both connected with the input end of an isolation optocoupler UC1, and the output end of the isolation optocoupler UC1 is connected with the second direct current output end of the bridge circuit DU1 through a resistor RC 1.
Furthermore, one end of a polarity capacitor CJ2 is connected between the resistor RJ10 and the base of the transistor T2, and the other end of the polarity capacitor CJ2 is grounded.
Further, the number of the speakers is not limited to 30.
To sum up, owing to adopted above-mentioned technical scheme, the beneficial effects of the utility model are that:
1. the detection range is large, and the method can automatically adapt to the detected physical quantity; so as to adapt to the condition of hanging different numbers of loudspeakers;
2. detecting physical quantity 'isolated sampling'; the differential amplifier circuit detects the "detected physical quantity" and the "amount of change in the detected physical quantity",
3. the detection result is output in a photoelectric isolation mode; pulse isolation output, simple circuit and low cost.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and that for those skilled in the art, other relevant drawings can be obtained according to the drawings without inventive effort, wherein:
FIG. 1 is a schematic diagram of the circuit for detecting a disconnection;
fig. 2 is a schematic circuit diagram of the speaker disconnection detection module of the present invention;
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the invention, i.e., the described embodiments are only some, but not all embodiments of the invention. The components of embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiment of the present invention, all other embodiments obtained by the person skilled in the art without creative work belong to the protection scope of the present invention.
It is noted that relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The features and properties of the present invention will be described in further detail with reference to the following examples.
Example one
The utility model discloses a differential formula level voltage audio output bus speaker detection circuitry that falls off that falls that preferred embodiment provided, as shown IN fig. 1, fig. 2, including broadcast audio power amplifier and n speakers, broadcast audio power amplifier passes through bus IN 1/bus IN2 and connects a speaker detection module that falls off, n is the natural number that is greater than 0;
wherein: the loudspeaker is connected with an interface OUT 1/an interface OUT2 of the loudspeaker disconnection detection module in parallel through an impedance matching audio transformer BY and an audio capacitor CY/capacitor CY', and a 1M omega diagnosis resistor is connected in each loudspeaker in parallel; the audio signal of the broadcast audio power amplifier is output IN a 110V constant voltage form, and DC48V direct current voltage is generated IN the audio signal, and the direct current voltage is respectively connected with a bus IN1 and a bus IN2 through two audio chokes; the audio choke serves to block the 110V audio signal of bus IN 1/bus IN2 from the dc power supply.
The loudspeaker disconnection detection module comprises a voltage nonpolar electricity taking circuit, a self-adaptive differential amplification circuit and a sampling isolation circuit;
the voltage nonpolar electricity taking circuit obtains a working power supply from a bus IN 1/a bus IN2 and supplies power to the differential amplification circuit and the sampling isolation circuit; the sampling isolation circuit collects sampling currents nI of n loudspeakers and outputs the sampling currents nI to a base stage of a triode T1/triode T2 through the output end of an isolation optocoupler UC 1; a resistor RJ9 is connected in series on a connecting circuit from the output end of the isolation optocoupler UC1 to the base stage of the triode T2, one end of a resistor RC2 is connected between the output end of the isolation optocoupler UC1 and the resistor RJ9, the other end of the resistor RC2 is grounded, and the resistor RC2 forms a sampling current nI into a voltage signal Vi for monitoring; one end of a resistor RC10 is connected between the resistor RJ9 and the base level of the triode T2, and the other end of the resistor RC10 is grounded;
the adaptive differential amplifying circuit comprises a transistor T1 and a transistor T2, wherein an input voltage signal Vi is divided by a resistor RJ9 and a resistor RJ10, an actual output voltage signal is Vi ', and when Vi' < Vi: the output level VC2 is more than VC1, the triode T1 is conducted, and the output optocoupler U2 has no output; and when Vi' is greater than Vi: the output level VC2 is less than VC1, the triode T2 is conducted, and the output end of the output optocoupler U2 is conducted.
During detection, firstly, the working power supply is obtained on the bus IN 1/the bus IN2 through the non-polarity power-taking circuit: the differential amplification circuit and the sampling isolation circuit are powered, and then the sampling circuit of the loudspeaker and the sampling currents nI of n loudspeakers are acquired through the sampling isolation circuit, wherein each loudspeaker is 48 uA; if the module is connected with 30 loudspeakers, the current to be detected is 48 × 30 ═ 1440uA
When 1 line is disconnected, the current to be detected is reduced by 48uA, namely 48/1440 is reduced by 3.3%;
the sampling current nI is proportionally transferred to the output end of the sampling current nI through an isolation optocoupler UC1 and an isolation optocoupler UC1, a voltage signal Vi for detection is formed on a resistor RC2 through a resistor RC2, the specific circuit does not limit the resistance value of the resistor RC2, a proper RC2 resistor value is selected according to actual conditions to obtain proper signal voltage,
the voltage signal Vi is divided by a resistor RJ9\ RJ10, so that the voltage signal input to the base level of the triode T2 is Vi ', which is about 98% of Vi under normal conditions, the detection signal Vi is larger than Vi', the triode T1 is conducted, at the moment, the output level VC2 is larger than VC1, and the output optocoupler U2 has no output; when the loudspeaker is disconnected, Vi can suddenly drop below Vi', at the moment, the triode T2 conducts the triode T1 to be cut off, and at the moment, the output level is turned over: VC1 is greater than VC2, an input light emitting tube of the optocoupler U2 is driven, and the output end of the optocoupler U2 is switched on; i.e. a drop of the loudspeaker is detected.
Example two
As shown in fig. 2, in this embodiment, on the basis of the first embodiment, it is preferable that the non-polarity power-taking circuit is composed of DU1, R1, R2, and C1; the 'loudspeaker drop-out detection module circuit' is connected to the inlets of the bus IN1 and the bus IN2 IN a non-polarized mode, and the circuit obtains a direct-current voltage of 48V at a GND end, and the voltage is used as the working voltage of the 'loudspeaker drop-out detection module circuit'. One end of a polarity capacitor CJ2 is connected between a resistor RJ10 and a base stage of a triode T2, the other end of the polarity capacitor CJ2 is grounded, the polarity of the capacitor CJ2 is used for keeping the stability of Vi ', when a loudspeaker is disconnected, Vi can be suddenly reduced to be below Vi', at the moment, a triode T2 conducts a triode T1 to be cut off, and at the moment, the output level is inverted: VC1 is greater than VC2, an input light emitting tube of the optocoupler U2 is driven, and the output end of the optocoupler U2 is switched on; the polar capacitor CJ2 is discharged through the resistor RJ5 and the resistor RJ9 when the T2 is turned on, so that Vi' is gradually decreased, then the voltage division effect of the resistor RJ9 and the resistor RJ10 appears, the differential circuit returns to the original state that the transistor T1 turns on the transistor T2 to be turned off, the whole response process of the off-line of the loudspeaker is completed, and the proper capacity of the CJ2 is selected to determine the proper response process time.
Preferably, a direct current resistor of 1M Ω is provided inside the speaker, the resistor RY is connected IN parallel to the "bus IN 1/bus IN 2", and a direct current of 48/1M Ω ═ 48uA is formed by the 48V direct current voltage through the resistor RY; and two AC DC blocking capacitors CY \ CY 'IN the loudspeaker enable audio signals of the bus IN 1/the bus IN2 to be applied to the audio transformer through the two AC DC blocking capacitors CY \ CY', so that the loudspeaker on the secondary side of the transformer produces sound.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not intended to limit the scope of the present invention, and any modifications, equivalents and improvements made by those skilled in the art within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (5)
1. A differential constant voltage audio output bus speaker detection circuitry that drops is characterized in that: the system comprises a broadcast audio power amplifier and n loudspeakers, wherein the broadcast audio power amplifier is connected with a loudspeaker disconnection detection module through a bus IN 1/a bus IN2, and n is a natural number greater than 0;
wherein: the interface OUT 1/interface OUT2 of the loudspeaker disconnection detection module is connected in parallel through an impedance matching audio transformer BY and an audio capacitor CY/capacitor CY', and a 1M omega diagnosis resistor is connected in parallel in each loudspeaker; the audio signal of the broadcast audio power amplifier is output IN a 110V constant voltage form, and DC48V direct current voltage is generated IN the audio signal, and the direct current voltage is respectively connected with a bus IN1 and a bus IN2 through two audio chokes; the loudspeaker disconnection detection module comprises a voltage nonpolar electricity taking circuit, a self-adaptive differential amplification circuit and a sampling isolation circuit;
the voltage nonpolar electricity taking circuit obtains a working power supply from a bus IN 1/a bus IN2 and supplies power to the differential amplification circuit and the sampling isolation circuit; the sampling isolation circuit collects sampling currents nI of n loudspeakers and outputs the sampling currents nI to a base stage of a triode T1/triode T2 through the output end of an isolation optocoupler UC 1; a resistor RJ9 is connected in series on a connecting circuit from the output end of the isolation optocoupler UC1 to the base stage of the triode T2, one end of a resistor RC2 is connected between the output end of the isolation optocoupler UC1 and the resistor RJ9, the other end of the resistor RC2 is grounded, and the resistor RC2 forms a sampling current nI into a voltage signal Vi for monitoring; one end of a resistor RC10 is connected between the resistor RJ9 and the base level of the triode T2, and the other end of the resistor RC10 is grounded;
the adaptive differential amplifying circuit comprises a transistor T1 and a transistor T2, wherein an input voltage signal Vi is divided by a resistor RJ9 and a resistor RJ10, an actual output voltage signal is Vi ', and when Vi' < Vi: the output level VC2 is more than VC1, the triode T1 is conducted, and the output optocoupler U2 has no output; and when Vi' is greater than Vi: the output level VC2 is less than VC1, the triode T2 is conducted, and the output end of the output optocoupler U2 is conducted.
2. The differential constant voltage audio output bus speaker drop detection circuit of claim 1, wherein: the voltage nonpolar electricity taking circuit comprises a bridge circuit DU1, wherein a first alternating current input end of the bridge circuit DU1 is connected with a bus IN1 through a resistor R1, a second alternating current input end of the bridge circuit DU1 is connected with a bus IN2 through a resistor R2, a first direct current output end is grounded, and a second direct current output end of the bridge circuit DU1 is grounded.
3. The differential constant voltage audio output bus speaker drop detection circuit of claim 1, wherein: the sampling isolation circuit comprises a capacitor CC1, one end of a capacitor CC1 is connected with the loudspeaker and the first alternating current input end of the bridge circuit DCI IN parallel, and the other end of the capacitor CC1 is connected with the second alternating current input end of the bridge circuit DCI and a bus IN2 IN parallel; the first direct current output end and the second direct current output end of the bridge circuit DCI are both connected with the input end of an isolation optocoupler UC1, and the output end of the isolation optocoupler UC1 is connected with the second direct current output end of the bridge circuit DU1 through a resistor RC 1.
4. The differential constant voltage audio output bus speaker drop detection circuit according to any of claims 1-3, wherein: one end of a polarity capacitor CJ2 is connected between the resistor RJ10 and the base stage of the transistor T2, and the other end of the polarity capacitor CJ2 is grounded.
5. The differential constant voltage audio output bus speaker drop detection circuit of claim 4, wherein: the number of the speakers is not limited to 30.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202022460906.5U CN213342686U (en) | 2020-10-30 | 2020-10-30 | Differential constant-voltage audio output bus loudspeaker disconnection detection circuit |
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| CN202022460906.5U CN213342686U (en) | 2020-10-30 | 2020-10-30 | Differential constant-voltage audio output bus loudspeaker disconnection detection circuit |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112218223A (en) * | 2020-10-30 | 2021-01-12 | 四川久远智能消防设备有限责任公司 | Differential constant-voltage audio output bus loudspeaker disconnection detection circuit |
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2020
- 2020-10-30 CN CN202022460906.5U patent/CN213342686U/en not_active Withdrawn - After Issue
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112218223A (en) * | 2020-10-30 | 2021-01-12 | 四川久远智能消防设备有限责任公司 | Differential constant-voltage audio output bus loudspeaker disconnection detection circuit |
| CN112218223B (en) * | 2020-10-30 | 2024-06-25 | 四川久远智能消防设备有限责任公司 | Differential constant-voltage audio output bus loudspeaker disconnection detection circuit |
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