CN112578688A - Projection device and sound output control device thereof - Google Patents

Projection device and sound output control device thereof Download PDF

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Publication number
CN112578688A
CN112578688A CN201910862310.7A CN201910862310A CN112578688A CN 112578688 A CN112578688 A CN 112578688A CN 201910862310 A CN201910862310 A CN 201910862310A CN 112578688 A CN112578688 A CN 112578688A
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China
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voltage
terminal
coupled
signal
resistor
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CN201910862310.7A
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Chinese (zh)
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黄信彰
廖政安
高福顺
周振城
陈宏霖
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Coretronic Corp
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Coretronic Corp
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Priority to CN201910862310.7A priority Critical patent/CN112578688A/en
Publication of CN112578688A publication Critical patent/CN112578688A/en
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    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05BCONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B19/00Programme-control systems
    • G05B19/02Programme-control systems electric
    • G05B19/04Programme control other than numerical control, i.e. in sequence controllers or logic controllers
    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03BAPPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B31/00Associated working of cameras or projectors with sound-recording or sound-reproducing means

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Circuit For Audible Band Transducer (AREA)

Abstract

A projection device and a sound output control device thereof are provided. The sound output control device includes an amplifier, a sound signal input terminal, and a judgment device. The amplifier is used to drive a speaker. The sound signal input terminal is detachably connected to the sound signal supplier and is used for receiving a sound signal. The judgment device carries out rectification action and filtering action aiming at the sound signal to generate processed voltage, and judges the specification of the sound signal supplier according to the voltage level of the processed voltage so as to generate a control signal. The judging device starts or stops the amplifier according to the control signal. The projection device and the sound output control device can prevent the damage caused by the inconsistency of the specification of the sound signal supplier and the set specification.

Description

Projection device and sound output control device thereof
Technical Field
The present invention relates to a projection device and a sound output control device thereof, and more particularly, to a projection device capable of automatically detecting the specification of a sound signal supplier and a sound output control device thereof.
Background
In the prior art, a connector can be provided on the projection apparatus for connecting different sound signal supplies (such as a microphone and a sound line input terminal). In addition, the projection device also provides an On Screen Display (OSD) function table to let the user preset the specification of the sound signal supplier. However, when the user's setting is not in accordance with the specification of the audio signal supplier actually plugged into the connector, the voltage of the audio signal supplied by the audio signal supplier is not in accordance with the preset specification, which may cause damage to the internal hardware components of the projector device.
Disclosure of Invention
The invention provides a projection device and a sound output control device thereof, which can prevent damage caused by the fact that the specification of a sound signal supplier does not conform to the set specification.
Other objects and advantages of the present invention will be further understood from the technical features disclosed in the present invention.
To achieve one or a part of or all of the above or other objects, the sound output control device of the present invention includes an amplifier, a sound signal input terminal, and a judgment device. The amplifier is used to drive a speaker. The sound signal input terminal is detachably connected to the sound signal supplier and is used for receiving a sound signal. The judgment device is coupled to the sound signal input terminal and the amplifier. The judgment device carries out rectification action and filtering action aiming at the sound signal to generate processed voltage, and judges the specification of the sound signal supplier according to the voltage level of the processed voltage so as to generate a control signal. The judging device starts or stops the amplifier according to the control signal.
To achieve one or a part of or all of the above or other objects, the projection apparatus of the present invention includes a speaker and a sound output control device. The sound output control device is coupled with the loudspeaker. The sound output control device includes an amplifier, a sound signal input terminal, and a judgment device. The sound signal input terminal is detachably connected to the sound signal supplier and is used for receiving a sound signal. The judgment device is coupled to the sound signal input terminal and the amplifier. The judgment device carries out rectification action and filtering action aiming at the sound signal to generate processed voltage, and judges the specification of the sound signal supplier according to the voltage level of the processed voltage so as to generate a control signal. The judging device starts or stops the amplifier according to the control signal.
Based on the above, the audio output control apparatus according to the embodiment of the invention generates the control signal by detecting the voltage of the audio signal received by the audio signal input terminal, and thereby determines the specification of the audio signal provider. The sound output control device of the embodiment of the invention starts or stops the amplifier according to the generated control signal, thereby ensuring that the hardware of the sound output control device is not damaged.
In order to make the aforementioned and other features and advantages of the invention more comprehensible, embodiments accompanied with figures are described in detail below.
Drawings
Fig. 1 is a schematic diagram illustrating an audio output control apparatus according to an embodiment of the invention.
Fig. 2 is a schematic diagram of a sound output control device according to another embodiment of the invention.
Fig. 3 is a schematic diagram illustrating an embodiment of a determining apparatus according to the present invention.
FIG. 4 is a schematic diagram showing the voltage relationship between the input and the output of the comparator.
Fig. 5 is a schematic view illustrating a projection apparatus according to an embodiment of the invention.
Detailed Description
Referring to fig. 1, fig. 1 is a schematic diagram illustrating a sound output control device according to an embodiment of the invention. The sound output control device 100 is coupled to a speaker 130. The audio output control device 100 includes an audio signal input terminal 110, an amplifier 120, and a determination device 140. Amplifier 120 is coupled to speaker 130 for generating a drive signal DRV to drive speaker 130. The sound signal input terminal 110 is detachably connected to a sound signal supplier (not shown), and receives a sound signal AIN from the sound signal supplier when connected thereto. The determining device 140 is coupled to the audio signal input terminal 110 and the amplifier 120. The judgment device 140 performs rectification and filtering operations on the audio signal AIN to generate a processed voltage, and judges the specification of the audio signal provider according to the voltage level of the processed voltage, thereby generating the control signal CTRL. The determining device 140 provides a control signal CTRL to the amplifier 120, so that the amplifier 120 is turned on or off according to the control signal CTRL.
In detail, the audio output control device 100 can be connected to a plurality of audio signal suppliers of different specifications, such as a microphone or a Line input (Line in) terminal of an electronic device, through only one audio signal input terminal 110. The voltage range of the audio signal AIN provided by the microphone is different from the voltage range of the audio signal AIN provided by the audio line input terminal. In the present embodiment, the determining device 140 performs a rectifying operation and a filtering operation on the audio signal AIN to generate a processed voltage, and compares the processed voltage with a preset reference voltage to generate a comparison result. The determining device 140 can obtain the specification of the audio signal provider according to the comparison result, and accordingly generate the control signal CTRL.
In the embodiment of the present invention, the determining device 140 may enable the amplifier 120 to be activated by the generated control signal CTRL when the specification of the audio signal provider conforms to the set specification, wherein the amplifier 120 may generate the driving signal DRV according to the audio signal AIN when being activated, and drive the speaker 130 by the driving signal DRV, so that the speaker 130 can smoothly play the audio according to the audio signal AIN. In contrast, the determining device 140 may generate the control signal CTRL to turn off the amplifier 120 when the specification of the audio signal provider does not conform to the set specification. Under this condition, the amplifier 120 does not generate the driving signal DRV, thereby effectively preventing the speaker 130 from being damaged due to receiving an out-of-specification signal.
Incidentally, the speaker 130 may be any type of horn.
Referring to fig. 2, fig. 2 is a schematic diagram illustrating a sound output control device according to another embodiment of the invention. The audio output control device 200 includes an audio signal input terminal 210, an amplifier 220, a judgment device 240, and a codec (codec) circuit 250. The amplifier 220 is connected to the speaker 230 for generating a driving signal DRV to drive the speaker 230. The sound signal input terminal 210 is detachably connected to a sound signal supplier (not shown), and receives a sound signal AIN from the sound signal supplier when connected thereto. The determining device 240 is coupled to the audio signal input terminal 210 and the amplifier 220. The codec circuit 250 is coupled between the audio signal input terminal 210 and the amplifier 220, and is used for performing a codec operation on the audio signal AIN and transmitting the codec audio signal EDAIN to the amplifier 220. The amplifier 220 can generate the driving signal DRV according to the encoded and decoded audio signal EDAIN in the activated state to drive the speaker 230 to generate audio effect.
It should be noted that, in the present embodiment, the determining device 240 includes a rectifier 241, a filter 242, a comparator 243 and an operator 244. The rectifier 241 is coupled to the sound signal input terminal 210 and receives the sound signal AIN. The rectifier 241 rectifies the audio signal AIN, which is an ac signal, and filters a negative half cycle voltage of the audio signal AIN, thereby generating a dc-like voltage DV. On the other hand, the filter 242 is coupled to the rectifier 241 and receives the dc-like voltage DV generated by the rectifier 241. The filter 242 is used for filtering the dc-like voltage DV to generate a processed voltage FDV. In this embodiment, the rectifier 241 may be a full-wave rectifier or a half-wave rectifier. The hardware structure of the rectifier 241 can be implemented by a rectifier known to those skilled in the art, without specific limitation.
In this embodiment, the filter 242 may be a low pass filter for filtering high frequency noise on the dc-like voltage DV to generate the processed voltage FDV. The filter 242 may pass a frequency band (pass band) and may be designed according to a practical application state of the sound output control apparatus 200 without a fixed limit.
In addition, in the present embodiment, the comparator 243 is coupled to the filter 242 and receives the processed voltage FDV generated by the filter 242. The comparator 243 is used for comparing the processed voltage FDV with a preset reference voltage to generate a comparison result CR. The voltage value of the processed voltage FDV generated by the filter 242 may also be different according to the specification of the audio signal provider of the audio signal AIN, based on that the audio signal AIN provided by the audio signal provider of different specifications operates in different voltage ranges. Taking the audio signal supplier as an example of the audio line input terminal of the electronic device, the processed voltage FDV generated by the filter 242 has a voltage amplitude of substantially 1 volt or less, regardless of the three-stage or four-stage audio line input terminal. In contrast, in the case of a microphone, which is an example of an audio signal provider, a microphone with a two-step joint (moving coil type), the voltage amplitude of the processed voltage FDV generated by the filter 242 in the left channel is substantially 1.6 volts or more, and the voltage amplitude of the processed voltage FDV generated by the filter 242 in the right channel is 0 volt. In a microphone (condenser type) with a three-section joint, the processed voltage FDV generated by the filter 242 has a voltage amplitude of substantially 4.24 v in both the left and right channels.
According to the above description, the designer can preset the reference voltage according to the audio signal suppliers with different specifications. And, when the comparison result CR generated by the comparator 243 indicates that the processed voltage FDV is greater than the preset reference voltage (e.g., VTH in fig. 4), it is determined that the sound signal provider is a microphone, and, on the contrary, when the comparison result CR generated by the comparator 243 indicates that the processed voltage FDV is less than the preset reference voltage (e.g., VTL in fig. 4), it is determined that the sound signal provider is a sound source line input terminal.
In addition, the operator 244 is coupled to the comparator 243. The operator 244 receives the comparison result CR generated by the comparator 243 and generates the control signal CTRL according to the comparison result CR. The operator 244 provides the control signal CTRL to the amplifier 220, and serves as a basis for whether the amplifier 220 is turned on.
On the other hand, in the present embodiment, the operator 244 is further coupled to the sound signal input terminal 210. The sound signal is inputted to the terminal 210 and can be effectively inserted for the presence or absence of the sound signal supplier to generate the detection signal DS. The operator 244 receives the detection signal DS and performs a logic operation on the detection signal DS and the comparison result CR to generate the control signal CTRL.
It should be noted that when the audio signal supplier is not inserted into the audio signal input terminal 210, the audio signal input terminal 210 can generate the detection signal DS with a first logic level (e.g., logic 0), and in contrast, when the audio signal supplier is effectively inserted into the audio signal input terminal 210, the audio signal input terminal 210 can generate the detection signal DS with a second logic level (e.g., logic 1), so that the arithmetic unit 244 can receive the detection signal DS corresponding to different logic levels.
On the other hand, the comparator 243 may generate the comparison result CR of a first logic level (e.g., logic 0) when determining that the voltage level of the processed voltage FDV is greater than the reference voltage, and the comparator 243 may generate the comparison result CR of a second logic level (e.g., logic 1) when determining that the voltage level of the processed voltage FDV is less than the reference voltage.
According to the above description, the operator 244 performs a logic operation (e.g., a logical and operation) on the detection signal DS and the comparison result CR to generate the control signal CTRL. That is, in the embodiment of the invention, the operator 244 may include a logic and gate for performing a logic and operation on the detection signal DS and the comparison result CR, and accordingly generating the control signal CTRL. To be more specific, if the apparatus is initially preset to have the sound signal supplier as a microphone, when the sound signal supplier is effectively inserted into the sound signal input terminal 210, the sound signal input terminal 210 can generate the detection signal DS with a second logic level (e.g., logic 1), and the comparator 243 determines that the sound signal supplier is a microphone, and the comparison result CR corresponds to a first logic level (e.g., logic 0), then the amplifier 220 is turned on; when the audio signal provider is effectively inserted into the audio signal input terminal 210, the audio signal input terminal 210 can generate the detection signal DS with a second logic level (e.g., logic 1), and the comparator 243 determines that the audio signal provider is the audio line input terminal, and the comparison result CR corresponds to the second logic level (e.g., logic 1), so that the amplifier 220 is turned off at this time; when the audio signal supplier is not inserted into the audio signal input terminal 210, the audio signal input terminal 210 can generate the detection signal DS with a first logic level (e.g., logic 0), and the comparison result CR of the comparator 243 is preset to the first logic level (e.g., logic 0), so that the amplifier 220 is turned on.
In other embodiments of the present invention, the computing unit 244 may also be a computing-capable controller. The calculator 244 is designed by Hardware Description Language (HDL) or any other digital Circuit design method known to those skilled in the art, and can be implemented by Field Programmable Gate Array (FPGA), Complex Programmable Logic Device (CPLD) or Application-specific Integrated Circuit (ASIC).
Referring to fig. 3, fig. 3 is a schematic diagram illustrating an implementation of a determining device according to an embodiment of the present invention. The determining apparatus 300 includes a rectifier 310, a filter 320, a comparator 330 and an operator 340. The rectifier 310 includes a diode D1 and a resistor R1. The anode terminal of the diode D1 receives the audio signal AIN, and the cathode terminal of the diode D1 is coupled to the first terminal of the resistor R1 and generates the dc-like voltage DV. The second terminal of the resistor R1 is coupled to the ground GND. In the present embodiment, the rectifier 310 is a half-wave rectifier and is used for filtering the negative half-cycle voltage of the audio signal AIN to generate the dc-like voltage DV.
It should be noted that, in order to increase the response rate of the rectifier 310, the diode D1 may be implemented by a Schottky (Schottky) diode.
In addition, the filter 320 includes a resistor R2 and a capacitor C1. The first terminal of the resistor R2 is coupled to the cathode terminal of the diode D1 and is used for receiving the dc-like voltage DV. The capacitor C1 is coupled in series between the second terminal of the resistor R2 and the reference ground. The resistor R2 and the capacitor C1 form a low pass filter for filtering high frequency noise like the dc voltage DV, so as to generate the processed voltage FDV at the coupling terminal of the resistor R2 and the capacitor C1 (the second terminal of the resistor R2).
In this embodiment, the comparator 330 includes a voltage divider 331, an operational amplifier 332, a capacitor C2, a feedback resistor Rf, and a pull-up resistor RPU. The voltage divider 331 is coupled between the power supply voltage PV1 and the ground reference GND, and the voltage divider 331 divides the power supply voltage PV1 and generates a divided voltage VA1 at an output terminal. The voltage divider 331 is formed by serially coupling resistors R3 and R4, wherein a first terminal of the resistor R3 receives the power voltage PV1, a second terminal of the resistor R3 is coupled to a first terminal of the resistor R4 and forms an output terminal of the voltage divider 331, and a second terminal of the resistor R4 is coupled to the ground reference GND.
On the other hand, the positive input terminal of the operational amplifier OP1 receives the divided voltage VA1, and the negative input terminal of the operational amplifier OP1 is coupled to the filter 320 for receiving the processed voltage FDV. The operational amplifier OP1 receives the power supply voltage PV1 as an operating voltage. The capacitor C2 is coupled between the power supply voltage PV1 and the ground GND to serve as a voltage stabilizing capacitor. The feedback resistor Rf is coupled to the negative-positive input terminal of the operational amplifier OP1 and the output terminal of the operational amplifier OP1 to provide a negative feedback path. The pull-up resistor RUP is coupled between the output terminal of the operational amplifier OP1 and the power voltage PV 2. In the present embodiment, the voltage values of the power voltage PV1 and the power voltage PV2 may be different or the same, and the voltage value of the power voltage PV1 may be higher than the voltage value of the power voltage PV 2.
In the present embodiment, the comparator 330 is a hysteresis comparator, such as a schmitt Trigger (schmitt Trigger). Specifically, please refer to fig. 3 and fig. 4 synchronously, wherein fig. 4 is a schematic diagram illustrating a voltage relationship between an input and an output of the comparator. The input of the comparator 330 is the processed voltage FDV, and the output of the comparator 330 is the comparison result CR. The comparator 330 provides a first sub-reference voltage VTH and a second sub-reference voltage VTL, wherein the first sub-reference voltage VTH is greater than the second sub-reference voltage VTL. The comparator 330 may provide the comparison result CR having a relatively low voltage level when the processed voltage FDV is greater than the first sub-reference voltage VTH, and may provide the comparison result CR having a relatively high voltage level when the processed voltage FDV is less than the second sub-reference voltage VTL. Also, the comparator 330 can maintain the voltage level of the comparison result CR unchanged when the processed voltage FDV is between the first sub-reference voltage VTH and the second sub-reference voltage VTL.
Through the hysteresis-type comparator 330 as shown in fig. 3, the comparator 330 can provide a relatively stable comparison result CR to stably control the on/off operation of the amplifier.
It should be noted that the circuit diagram of the hysteresis-type comparator 330 shown in fig. 3 is merely an illustrative example. In the embodiment of the present invention, other forms of hysteresis type comparator circuits can be applied to the present invention, and there is no particular limitation.
Taking the microphone as an example of the setting specification set by the user, when the audio signal supplier is the microphone, the comparator 330 receives the processed voltage FDV greater than the first sub-reference voltage VTH and generates the comparison result CR of logic 0 (first logic level). The comparator 330 transmits the comparison result CR of logic 0 to the subsequent operator 340 for logical operation, which generates a control signal of logic 1 to turn on the amplifier for performing the sound effect playing operation. In contrast, when the audio signal supplier is the audio line input terminal, the comparator 330 receives the processed voltage FDV smaller than the second sub-reference voltage VTL and generates the comparison result CR of logic 1 (the second logic level). Through the logic operation of the operator 340, a control signal of logic 0 can be generated to turn off the amplifier, thereby preventing the hardware components (e.g., speaker) from being damaged.
Referring to fig. 5, fig. 5 is a schematic view illustrating a projection apparatus according to an embodiment of the invention. In fig. 5, the projection apparatus 500 includes a speaker 560 and a sound output control device 520, and the projection apparatus 500 further includes a projection lens 510 and a display unit 540. The projection lens 510 is used for projecting a display image to the outside of the projection apparatus 500. The display unit 540 may be disposed on a housing (not numbered) of the projection apparatus 500, and may provide a graphical user interface. In this embodiment, the user can set the setting specification (for example, a microphone or a sound source line input terminal) of the sound signal supplier to be inserted through the display unit 540. In another embodiment of the present invention, the display unit 540 can be formed by a display image projected by the projection lens 510. The projection lens 510 can project a display image as a setting screen, provide the setting screen as a graphical user interface, and provide a user to execute a setting operation of a setting specification of the audio signal provider through the graphical user interface, for example, the setting specification of the audio signal provider that the user can set in advance is a microphone.
The sound output control device 520 in the present embodiment can be implemented by the sound output control device 100 or 200 in the foregoing embodiment. The audio output control device 520 is detachably connected to the audio signal supplier AJ through the audio signal input terminal 530. When the audio signal supplier AJ is plugged into the audio signal input terminal 530, the audio output control device 520 may determine the specification of the audio signal supplier AJ according to the voltage range of the audio signal supplied by the audio signal supplier AJ. And when the specification of the audio signal supplier AJ conforms to the specification set by the user, the audio output control device 520 may drive the speaker 560 by activating an internal amplifier. In contrast, when the specification of the audio signal supplier AJ does not conform to the specification set by the user, the audio output control device 520 may stop driving the speaker 560 by turning off an internal amplifier (not shown), and maintain the hardware components of the audio output control device 520 and the speaker 560 from being damaged.
Additionally, the projection apparatus 500 may further include a warning device for sending a warning signal when the audio output control device 520 determines that the specification of the audio signal supplier AJ does not conform to the set specification set by the user. In this embodiment, the warning device may be disposed on the display unit 540, and display a warning screen (warning signal) through the display unit 540 to inform the user that the specification of the audio signal provider AJ does not conform to the specification set by the user. Of course, the warning screen may be projected onto the display screen through the projection lens 510.
In other embodiments of the present invention, the warning device may also be an additional buzzer or a light emitting element (e.g., a light emitting diode), and notify the user that the specification of the audio signal provider AJ does not conform to the specification set by the user through a visual or audible warning signal.
In summary, the specification of the audio signal provider is determined by detecting the voltage value of the audio signal received at the audio signal input terminal. And the amplifier is turned on or off according to the specification of the sound signal supplier. When the specification of the sound signal supplier is not in accordance with the set specification, the sound signal which is not in accordance with the specification can be prevented from entering the loudspeaker by closing the operation of the amplifier, and the phenomenon that hardware components are damaged is avoided.
However, the above description is only a preferred embodiment of the present invention, and the scope of the present invention should not be limited thereby, and all the simple equivalent changes and modifications made according to the claims and the summary of the invention are still included in the scope of the present invention. It is not necessary for any embodiment or claim of the invention to address all of the objects, advantages, or features disclosed herein. In addition, the abstract and the title of the invention are provided for assisting the retrieval of patent documents and are not intended to limit the scope of the invention. Furthermore, the terms "first", "second", and the like in the description or the claims are used only for naming elements (elements) or distinguishing different embodiments or ranges, and are not used to limit upper or lower limits on the number of elements.
Description of reference numerals:
100. 200, 520: sound output control device
110. 210, 530: sound signal input terminal
120. 220, and (2) a step of: amplifier with a high-frequency amplifier
130. 230, 560: loudspeaker
140. 240, 300: judging device
241. 310: rectifier
242. 320, and (3) respectively: filter with a filter element having a plurality of filter elements
243. 330: comparator with a comparator circuit
244. 340, and (3): arithmetic unit
250: encoding and decoding circuit
500: projection device
510: projection lens
540: display unit
And (3) AIN: sound signal
AJ: sound signal supplier
C1: capacitor with a capacitor element
CR: comparison results
CTRL: control signal
D1: diode with a high-voltage source
DRV: drive signal
And (2) DS: detecting the signal
DV: like DC voltage
EDAIN: coded and decoded sound signal
FDV: voltage after treatment
GND: reference ground
OP 1: operational amplifier
PV1, PV 2: supply voltage
R1-R4: resistance (RC)
Rf: feedback resistor
RPU: pull-up resistor
VTH, VTL: the sub-reference voltages.

Claims (26)

1. An audio output control device comprising an amplifier, an audio signal input terminal, and a judgment device, wherein:
the amplifier is used for driving a loudspeaker;
the sound signal input terminal is detachably connected with a sound signal supplier and is used for receiving a sound signal; and
the judging device is coupled to the sound signal input terminal and the amplifier, rectifies and filters the sound signal to generate a processed voltage, judges the specification of the sound signal supplier according to the voltage level of the processed voltage, and generates a control signal according to the specification,
the judging device starts or stops the amplifier according to the control signal.
2. The apparatus according to claim 1, wherein the determining means compares a voltage level of the processed voltage with a predetermined reference voltage to generate the control signal.
3. The audio output control device according to claim 1, wherein the amplifier is turned on in accordance with the control signal when the specification of the audio signal supplier coincides with a set specification, and turned off in accordance with the control signal when the specification of the audio signal supplier does not coincide with the set specification.
4. The audio output control device of claim 1, wherein the audio signal input terminal generates a detection signal according to the presence or absence of connection of the audio signal supplier, and the determining device further generates the control signal according to the detection signal and the voltage level of the processed voltage.
5. The sound output control device according to claim 4, wherein the judging means includes:
a rectifier coupled to the audio signal input terminal for rectifying the audio signal to generate a DC-like voltage;
a filter coupled to the rectifier for filtering the DC-like voltage to generate the processed voltage;
a comparator coupled to the filter for comparing the voltage level of the processed voltage with a predetermined reference voltage to generate a comparison result; and
and the arithmetic unit is coupled with the comparator and generates the control signal according to the comparison result and the detection signal.
6. The sound output control device of claim 5, wherein the rectifier comprises a diode having an anode terminal and a cathode terminal, the anode terminal of the diode being configured to receive the sound signal, the cathode terminal of the diode being configured to generate the DC-like voltage, and a resistor coupled between the cathode terminal of the diode and a reference ground terminal.
7. The sound output control device according to claim 5, wherein the filter includes a resistor and a capacitor; the resistor has a first terminal for receiving the dc voltage and a second terminal for generating the processed voltage, and the capacitor is coupled between the second terminal of the resistor and a reference ground terminal.
8. The apparatus according to claim 5, wherein the reference voltage comprises a first sub-reference voltage and a second sub-reference voltage, the comparator generates the comparison result of a first logic level when determining that the voltage level of the processed voltage is greater than the first sub-reference voltage, the comparator generates the comparison result of a second logic level when determining that the voltage level of the processed voltage is less than the second sub-reference voltage,
wherein the first sub-reference voltage is greater than the second sub-reference voltage, and the first logic level is complementary to the second logic level.
9. The sound output control device according to claim 5, wherein the comparator includes:
a voltage divider that divides a first power supply voltage and generates a divided voltage at an output terminal of the voltage divider;
an operational amplifier having a negative input terminal, a positive input terminal for receiving the divided voltage, and an output terminal for generating the comparison result, the negative input terminal of the operational amplifier receiving the processed voltage;
a feedback resistor coupled between the positive input of the operational amplifier and the output of the voltage divider; and
a pull-up resistor having a first terminal for receiving a second supply voltage and a second terminal coupled to the output terminal of the operational amplifier.
10. The sound output control device according to claim 9, wherein the voltage divider includes:
a first resistor and a second resistor coupled in series between the first power voltage and the reference ground, wherein the coupled ends of the first resistor and the second resistor form the output terminal of the voltage divider.
11. The apparatus of claim 5, wherein the operator comprises an AND gate, the AND gate receiving the comparison result and the detection signal and performing a logical AND operation to generate the control signal.
12. The sound output control device according to claim 1, characterized by further comprising:
and a codec circuit coupled between the amplifier and the audio signal input terminal, for performing a codec operation on the audio signal.
13. A projection apparatus, comprising a speaker and a sound output control device, wherein the sound output control device is coupled to the speaker, and the sound output control device comprises an amplifier, a sound signal input terminal, and a determination device, wherein:
the amplifier is used for driving the loudspeaker;
the sound signal input terminal is detachably connected with a sound signal supplier and is used for receiving a sound signal; and
the judging device is coupled to the sound signal input terminal and the amplifier, rectifies and filters the sound signal to generate a processed voltage, judges the specification of the sound signal supplier according to the voltage level of the processed voltage, and generates a control signal according to the specification,
the judging device starts or stops the amplifier according to the control signal.
14. The projection apparatus according to claim 13, wherein the determining means compares the voltage level of the processed voltage with a predetermined reference voltage to generate the control signal.
15. The projection apparatus as claimed in claim 13, wherein the amplifier is activated according to the control signal when the specification of the audio signal supplier is in compliance with a set specification, and the amplifier is deactivated according to the control signal when the specification of the audio signal supplier is not in compliance with the set specification.
16. The projection device of claim 13, further comprising:
and the warning device is coupled to the judging device and sends a warning signal when the specification of the sound signal supplier does not accord with the set specification.
17. The projection apparatus as claimed in claim 13, wherein the audio signal input terminal generates a detection signal according to whether the audio signal supplier is connected or not, and the determining means further generates the control signal according to the detection signal and a voltage level of the processed voltage.
18. The projection apparatus according to claim 17, wherein the judging means comprises:
a rectifier coupled to the audio signal input terminal for rectifying the audio signal to generate a DC-like voltage;
a filter coupled to the rectifier for filtering the DC-like voltage to generate the processed voltage;
a comparator coupled to the filter for comparing the voltage level of the processed voltage with a predetermined reference voltage to generate a comparison result; and
and the arithmetic unit is coupled with the comparator and generates the control signal according to the comparison result and the detection signal.
19. The projection device of claim 18, wherein the rectifier comprises a diode and a resistor; the diode has an anode terminal and a cathode terminal, the anode terminal of the diode is used for receiving the sound signal, the cathode terminal of the diode is used for generating the DC-like voltage, and the resistor is coupled between the cathode terminal of the diode and a reference ground terminal.
20. The projection device of claim 18, wherein the filter comprises a resistor and a capacitor; the resistor has a first terminal for receiving the dc voltage and a second terminal for generating the processed voltage, and the capacitor is coupled between the second terminal of the resistor and a reference ground terminal.
21. The projection apparatus according to claim 18, wherein the reference voltage includes a first sub-reference voltage and a second sub-reference voltage, the comparator generates the comparison result of a first logic level when determining that the voltage level of the processed voltage is greater than the first sub-reference voltage, the comparator generates the comparison result of a second logic level when determining that the voltage level of the processed voltage is less than the second sub-reference voltage,
wherein the first sub-reference voltage is greater than the second sub-reference voltage, and the first logic level is complementary to the second logic level.
22. The projection device of claim 18, wherein the comparator comprises:
a voltage divider that divides a first power supply voltage and generates a divided voltage at an output terminal of the voltage divider;
an operational amplifier having a negative input terminal, a positive input terminal for receiving the divided voltage, and an output terminal for generating the comparison result, the negative input terminal of the operational amplifier receiving the processed voltage;
a feedback resistor coupled between the positive input of the operational amplifier and the output of the voltage divider; and
a pull-up resistor having a first terminal for receiving a second supply voltage and a second terminal coupled to the output terminal of the operational amplifier.
23. The projection device of claim 22, wherein the voltage divider comprises:
a first resistor and a second resistor coupled in series between the first power voltage and the reference ground, wherein the coupled ends of the first resistor and the second resistor form the output terminal of the voltage divider.
24. The projection apparatus according to claim 18, wherein the operator comprises an AND gate, the AND gate receiving the comparison result and the detection signal and generating the control signal.
25. The projection apparatus as claimed in claim 13, wherein the audio output apparatus further comprises a codec circuit coupled between the amplifier and the audio signal input terminal for performing a codec operation on the audio signal.
26. The projection device of claim 13, further comprising:
and the display unit provides a setting interface of the setting specification of the sound signal supplier.
CN201910862310.7A 2019-09-12 2019-09-12 Projection device and sound output control device thereof Pending CN112578688A (en)

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Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101111094A (en) * 2006-07-21 2008-01-23 大同股份有限公司 Noise preventing module and its public address set
CN201113928Y (en) * 2007-08-06 2008-09-10 普诚科技股份有限公司 Sound control device
US20090316926A1 (en) * 2008-06-19 2009-12-24 Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. Audio device
CN101989836A (en) * 2009-08-04 2011-03-23 纬创资通股份有限公司 Efficient audio amplifier and related method thereof
TW201112781A (en) * 2009-09-16 2011-04-01 Himax Media Solutions Inc Audio output devices
CN102055418A (en) * 2009-10-26 2011-05-11 成都芯源系统有限公司 Audio amplifier and audio amplifying method
JP2013064656A (en) * 2011-09-17 2013-04-11 Denso Corp Abnormality detection device for speaker circuit to produce vehicular travel notification sound
JP2013093666A (en) * 2011-10-24 2013-05-16 Rohm Co Ltd Audio signal processing circuit and electronic apparatus using the same
CN103369427A (en) * 2012-03-29 2013-10-23 创杰科技股份有限公司 Audio amplifying device
CN103888874A (en) * 2014-03-25 2014-06-25 建荣集成电路科技(珠海)有限公司 Audio input and output device and audio input and output method
CN204929213U (en) * 2015-08-10 2015-12-30 深圳市冠旭电子有限公司 Audio signal detects control circuit
CN105338446A (en) * 2014-07-04 2016-02-17 鸿富锦精密工业(深圳)有限公司 Audio channel control circuit
CN106658295A (en) * 2017-01-20 2017-05-10 深圳市中移联半导体科技有限公司 Loudspeaker direct voltage detection circuit
WO2019002417A1 (en) * 2017-06-28 2019-01-03 Kraydel Limited Sound responsive device and method
CN210573245U (en) * 2019-09-12 2020-05-19 中强光电股份有限公司 Projection device and sound output control device thereof

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101111094A (en) * 2006-07-21 2008-01-23 大同股份有限公司 Noise preventing module and its public address set
CN201113928Y (en) * 2007-08-06 2008-09-10 普诚科技股份有限公司 Sound control device
US20090316926A1 (en) * 2008-06-19 2009-12-24 Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. Audio device
CN101989836A (en) * 2009-08-04 2011-03-23 纬创资通股份有限公司 Efficient audio amplifier and related method thereof
TW201112781A (en) * 2009-09-16 2011-04-01 Himax Media Solutions Inc Audio output devices
CN102055418A (en) * 2009-10-26 2011-05-11 成都芯源系统有限公司 Audio amplifier and audio amplifying method
JP2013064656A (en) * 2011-09-17 2013-04-11 Denso Corp Abnormality detection device for speaker circuit to produce vehicular travel notification sound
JP2013093666A (en) * 2011-10-24 2013-05-16 Rohm Co Ltd Audio signal processing circuit and electronic apparatus using the same
CN103369427A (en) * 2012-03-29 2013-10-23 创杰科技股份有限公司 Audio amplifying device
CN103888874A (en) * 2014-03-25 2014-06-25 建荣集成电路科技(珠海)有限公司 Audio input and output device and audio input and output method
CN105338446A (en) * 2014-07-04 2016-02-17 鸿富锦精密工业(深圳)有限公司 Audio channel control circuit
CN204929213U (en) * 2015-08-10 2015-12-30 深圳市冠旭电子有限公司 Audio signal detects control circuit
CN106658295A (en) * 2017-01-20 2017-05-10 深圳市中移联半导体科技有限公司 Loudspeaker direct voltage detection circuit
WO2019002417A1 (en) * 2017-06-28 2019-01-03 Kraydel Limited Sound responsive device and method
CN210573245U (en) * 2019-09-12 2020-05-19 中强光电股份有限公司 Projection device and sound output control device thereof

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