Patent Application
20150055806
The present disclosure relates to an audio adjustment circuit and an electronic device using the audio adjustment circuit.
Electronic devices, such as televisions and air conditioners, include a buzzer for indicating abnormal states of the electronic devices. However, there is only one tone frequency outputted to indicate different abnormal states, so it is inconvenient to determine the cause of the abnormal state.
The components of the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the embodiment of an electronic device. Moreover, in the drawings, like reference numerals designate corresponding parts throughout several views.
The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean “at least one.” The references “a plurality of” and “a number of” mean “at least two.” Embodiments of the present disclosure will be described in detail with reference to the drawings.
The electronic device 100 includes a power supply 10, an adjustment circuit 20, and an audio outputting module 30.
The power supply 10 provides a working voltage. In one embodiment, the working voltage is 5 volts.
The adjustment circuit 20 can be electrically coupled between the power supply 10 and the audio outputting module 30. The adjustment circuit 20 can receive the working voltage from the power supply 10 and outputs different driving voltages to the audio outputting module 30. The adjustment circuit 20 can include a control unit 21, a switch unit 23, and an adjustment unit 25.
The control unit 21 can be electrically connected to the switch unit 23 and the adjustment unit 25. The control unit 21 can include a first pin P1 and a second pin P2. The first pin P1 and the second pin P2 can each output a first control signal and a second control signal to the switch unit 23 and the adjustment unit 25. In one embodiment, based on different states of the electronic device 100, the control unit 21 can control the first pin P1 and the second pin P2 to output the first control signal and/or the second control signal in different combination. In one embodiment, the first control signal can be logic-high signal, and the second control signal can be a logic-low signal.
The switch unit 23 is electrically connected to the power supply 10, the control unit 21, and the adjustment unit 25. The switch unit 23 can electrically couple the power supply 10 to the adjustment unit 25 when at least one of the first pin P1 or the second pin P2 outputs the first control signal. The switch unit 23 can disconnect the power supply 10 from the adjustment unit 25 when both the first pin P1 and the second pin P2 output the second control signal.
The adjustment unit 25 can be electrically connected to the control unit 21, the switch unit 23, and the audio outputting module 30. The adjustment unit 25 outputs different driving voltages to the audio outputting module 30 based on different combinations of the first and second control signals outputted by the control unit 21 when the power supply 10 is electrically coupled to the adjustment unit 25. When both of the first pin P1 and the second pin P2 output the first control signal, the adjustment unit 25 can output a first driving voltage. When the first pin P1 outputs the first control signal and the second pin P2 outputs the second control signal, the adjustment unit 25 can output a second driving voltage. When the first pin P1 outputs the second control signal and the second pin P2 outputs the first control signal, the adjustment unit 25 can output a third driving voltage. The adjustment unit 25 can stop outputting driving voltages when the switch unit 23 decouples the power supply 10 from the adjustment unit 25. In one embodiment, the values of the first driving voltage, the second driving voltage, and the third driving voltage can decrease in that order. The first driving voltage is substantially equal to the working voltage.
The audio outputting module 30 can be electrically connected to the adjustment unit 25. The audio outputting module 30 can output different tone frequencies based on the different driving voltages. In one embodiment, the audio outputting module 30 is a buzzer. The tone frequencies are directly proportional to the values of the driving voltage. In another embodiment, the audio outputting module 30 can output a same tone frequency with different volumes based on the different driving voltages.
The switch unit 23 can include a first transistor Q1, a first diode D1, a second diode D2, and a first resistor Ra. A base of the first transistor Q1 can be electrically connected to the first pin P1 through the first diode D1. An emitter of the first transistor Q1 can be electrically connected to the adjustment unit 25. A collector of the first transistor Q1 can be electrically connected to the power source V1. An anode of the first diode D1 can be connected to the first pin P1. A cathode of the first diode D1 can be electrically connected to the base of the first transistor Q1. An anode of the second diode D2 can be electrically connected to the second pin P2. A cathode of the second diode D2 can be electrically connected to the base of the first transistor Q1. A first terminal of the first resistor Ra can be electrically connected to the base of the first transistor Q1. A second terminal of the first resistor Ra can be grounded. In one embodiment, the first transistor Q1 can be an npn-type bipolar junction transistor.
The adjustment unit 25 can include a second transistor Q2, a third transistor Q3, a third diode D3, a first limiting resistor R1, a second limiting resistor R2, and a third limiting resistor R3. A gate of the second transistor Q2 can be connected to the first pin P1. A source of the second transistor Q2 can be connected to the emitter of the first transistor Q1. A drain of the second transistor Q2 can be electrically connected to the audio outputting module 30. A gate of the third transistor Q3 can be electrically connected to the second pin P2. A source of the third transistor Q3 can be grounded. A drain of the third transistor Q3 can be electrically connected to the audio outputting module 30 through the third diode D3. An anode of the third diode D3 can be electrically connected to the drain of the third transistor Q3. A cathode of the third diode D3 can be electrically connected to the drain of the second transistor Q2. The first limiting resistor R1 can be electrically connected between the source and the drain of the second transistor Q2. The second limiting resistor R2 can be electrically connected between the source and the drain of the third transistor Q3. The third limiting resistor R3 can be electrically connected between the gate and the source of the third transistor Q3. In one embodiment, the second transistor Q2 can be a p-channel enhancement type-metal oxide semiconductor field-effect transistor (MOSFET), and the third transistor Q3 can be an n-channel enhancement type-metal oxide semiconductor field-effect transistor (MOSFET). A resistance of the second limiting resistor R2 can be four times greater than a resistance of the first limiting resistor R1.
A working method of the electronic device 100 can be described as follow. When both the first pin P1 and the second pin P2 output the first control signal, the first diode D1 and the second diode D2 turn on, and a voltage difference between the base and the emitter of the first transistor Q1 can be greater than 0.7 volt, which can cause the first transistor Q1 to turn on, and the source of the second transistor Q2 to be electrically connected to the power source V1. When the voltage difference between the gate and the source of the second transistor Q2 can be less than 0 volts, the second transistor Q2 can turn on. When the voltage difference between the gate and the source of the third transistor Q3 can be greater than 0 volts, the third transistor Q3 can turn off, which can cause the audio outputting module 30 to output a first tone frequency.
When the first pin P1 outputs the first control signal and the second pin P2 outputs the second control signal, the first diode D1 turns on and the second diode D2 turns off. When the voltage difference between the base and the emitter of the first transistor Q1 can be greater than 0.7 volt, the first transistor Q1 turns on, which can cause the source of the second transistor Q2 to be electrically connected to the power source V1. When the voltage difference between the gate and the source of the second transistor Q2 can be less than 0 volt, the second transistor Q2 can turn on. When the voltage difference between the gate and the source of the third transistor Q3 can be greater than 0 volts, the third transistor Q3 can turn off, which can cause the audio outputting module 30 to output a second tone frequency.
When the first pin P1 outputs the second control signal and the second pin P2 outputs the first control signal, the first diode D1 can turn off and the second diode D2 can turn on. When the voltage difference between the base and the emitter of the first transistor Q1 can be greater than 0.7 volt, the first transistor Q1 turns on, which can cause the source of the second transistor Q2 to be electrically connected to the power source V1. When the voltage difference between the gate and the source of the second transistor Q2 can be greater than 0 volt, the second transistor Q2 can turn off. When the voltage difference between the gate and the source of the third transistor Q3 can be less than 0 volt, the third transistor Q3 can turn on, which can cause the audio outputting module 30 to outputted a third tone frequency.
When both the first pin P1 and the second pin P2 output the second control signal, the first diode D1 can turn off and the second diode D2 can turn on. When the voltage difference between the base and the emitter of the first transistor Q1 can be less than 0.7 volts, the first transistor Q1 can turn off, which can cause the audio outputting module 30 to stop outputting tone frequency.
In use, the electronic device 100 can be capable of outputting different tone frequencies based on different driving voltage of the electronic device 100.
While various exemplary and preferred embodiments have been described, the disclosure is not limited thereto. On the contrary, various modifications and similar arrangements (as would be apparent to those skilled in the art) are intended to also be covered. Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2013103672557 | Aug 2013 | CN | national |
