Extremely simple circuit

Abstract

The utility model relates to the technical field of microphone rods, in particular to an extremely simple circuit, which comprises a voltage microphone V-MIC2, an electret microphone MIC2, a microphone negative terminal MIC1-N, an audio signal port GPIO-12 and an external microphone rod. Wherein the output pin of the voltage microphone V-MIC2 is connected with a resistor R26, the other end of the resistor R26 is connected with a resistor R27, and the other end of the resistor R27 is connected with the output end of the electret microphone MIC2. Through the arrangement of the circuit, the circuit has the advantages of smaller size of an electronic wire, simpler circuit, short-circuit protection function and lower cost, and solves the problems that a 2PIN is used as a microphone working channel, a 1PIN is additionally used for detecting insertion and extraction, and a 1PIN is additionally used for detecting a key, so that the size of a connector is larger, the size of an earphone becomes larger, and the cost is reduced. In the prior art, the number of the electronic wires is changed from two to four, and the electronic wires become thicker, so that the open type Bluetooth telephone traffic earphone cannot realize microphone rod detection and stable conversation effect in a narrow contact area.

Description

Technical Field

[0001] The utility model relates to the technical field of microphone poles, in particular to a minimalist circuit. Background Art

[0002] With the continuous development of the application of wireless call-type headsets and open-back headset technology, wireless open-back headsets tend to be compact, portable and easy to store in different usage scenarios. The microphone boom (microphone boom) must ensure the call quality while also detecting the status of the microphone being plugged in and out.

[0003] Currently, 2 pins are used as the microphone working channel, plus 1 pin is used to detect insertion and removal, and another 1 pin is used to detect the button. This will make the connector larger, and thus the size of the headset larger. The electronic wire will also be increased from two to four and become thicker. As a result, the open Bluetooth headset cannot achieve microphone pole detection within the narrow contact area while maintaining a stable call quality. To this end, we propose a minimalist circuit. Utility Model Content

[0004] The purpose of the utility model is to provide a minimalist circuit with the advantages of smaller electronic wire volume, simpler circuit, short-circuit protection function and lower cost. It solves the problem of 2PIN as microphone working channel plus 1PIN detection insertion and removal, and another 1PIN detection button. This will make the connector size larger, and thus the earphone size larger, and the electronic wire will be changed from two to four and become thicker, resulting in the problem that on open Bluetooth call headsets, it is impossible to achieve microphone pole detection and stable call effect within a small contact area.

[0005] To achieve the above objectives, the present invention provides the following technical solutions: a minimalist circuit comprising:

[0006] Voltage microphone V-MIC2, electret microphone MIC2, microphone negative terminal ‌MIC1-N, audio signal port GPIO-12, external microphone rod;

[0007] The output pin of the voltage microphone V-MIC2 is connected to a resistor R26, the other end of the resistor R26 is connected to a resistor R27, the other end of the resistor R27 is connected to the output end of the electret microphone MIC2, a capacitor C34 is connected in parallel between the other end of the resistor R26 and one end of the resistor R27, and the other end of the capacitor C34 is grounded;

[0008] The output pin of the electret microphone MIC2 is connected in parallel with a capacitor C42 and a diode E28, the other end of the capacitor C42 is grounded, and the input end of the diode E28 is grounded;

[0009] The output pin of the negative terminal ‌MIC1-N of the microphone is connected to a capacitor C33, the other end of the capacitor C33 is connected in parallel with a resistor R20, a capacitor C41, and a diode E27, and the other ends of the resistor R20 and the capacitor C41 and the input end of the diode E27 are all grounded;

[0010] The output pin of the audio signal port GPIO-12 is connected to a resistor R7, and the other end of the resistor R27 is connected in parallel to the output pin of the electret microphone MIC2;

[0011] A selection switch is connected in parallel between the positive input end and the negative input end of the external microphone rod.

[0012] Preferably, the resistor R26 is 1K, the resistor R27 is 2K, and the capacitor C34 is 4.7uF.

[0013] Preferably, the capacitor C41 and the capacitor C42 are both 10nF.

[0014] Preferably, the capacitor C33 is 1uF, and the resistor R20 is 1K.

[0015] Preferably, the resistor R7 is 0R.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0017] 1. This utility model uses hardware circuits with software debugging to multiplex the insertion detection and button press detection circuits on a 2-pin microphone, making the headset size smaller and able to detect microphone insertion and removal without affecting the call quality.

[0018] 2. The utility model can realize the three functions of microphone insertion detection, key operation detection and short circuit protection through the 2PIN method, which can save costs and simplify user operation. The circuit is simple, which can facilitate the miniaturization and lightweight design of the structure and enhance the user's wearing experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a circuit diagram of the utility model. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0021] See also Figure 1 As shown, the utility model provides a technical solution: a minimalist circuit, including: a voltage microphone V-MIC2, an electret microphone MIC2, a microphone negative terminal ‌MIC1-N, an audio signal port GPIO-12, and an external microphone rod;

[0022] The output pin of the voltage microphone V-MIC2 is connected to a resistor R26, the other end of the resistor R26 is connected to a resistor R27, the other end of the resistor R27 is connected to the output end of the electret microphone MIC2, a capacitor C34 is connected in parallel between the other end of the resistor R26 and one end of the resistor R27, and the other end of the capacitor C34 is grounded;

[0023] The output pin of the electret microphone MIC2 is connected in parallel with a capacitor C42 and a diode E28, the other end of the capacitor C42 is grounded, and the input end of the diode E28 is grounded;

[0024] The negative terminal of the microphone ‌MIC1-N is connected to a capacitor C33. The other end of the capacitor C33 is connected in parallel with a resistor R20, a capacitor C41, and a diode E27. The other ends of the resistor R20 and the capacitor C41, as well as the input end of the diode E27, are all grounded.

[0025] The output pin of the audio signal port GPIO-12 is connected to a resistor R7, and the other end of the resistor R27 is connected in parallel to the output pin of the electret microphone MIC2;

[0026] A selection switch is connected in parallel between the positive input terminal and the negative input terminal of the external microphone rod.

[0027] Specifically, the resistor R26 is 1K, the resistor R27 is 2K, and the capacitor C34 is 4.7uF.

[0028] Specifically, the capacitor C41 and the capacitor C42 are both 10 nF.

[0029] Specifically, the capacitor C33 is 1 uF, and the resistor R20 is 1K.

[0030] Specifically, the resistor R7 is 0R.

[0031] This technical solution: Because the microphone output impedance is 2.2K, the microphone power supply is 1.8V from the chip. When not inserted, the detection pin is 1.8V. When inserted, the microphone is pulled down and then the voltage is detected through the voltage divider to 1.2V. When the button is pressed, it is 0V, and there is a DC blocking capacitor for MIC short-circuit protection. The software ADC pin detects voltage changes to determine whether it is inserted and whether the button is pressed, thereby achieving the goals of smaller electronic wire size, simpler circuit, short-circuit protection function and lower cost.

[0032] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit the scope of protection of the utility model. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the utility model.

Claims

1. A minimalist circuit, characterized in that: include: Voltage microphone V-MIC2, electret microphone MIC2, microphone negative terminal ‌MIC1-N, audio signal port GPIO-12, external microphone rod; The output pin of the voltage microphone V-MIC2 is connected to a resistor R26, the other end of the resistor R26 is connected to a resistor R27, the other end of the resistor R27 is connected to the output end of the electret microphone MIC2, a capacitor C34 is connected in parallel between the other end of the resistor R26 and one end of the resistor R27, and the other end of the capacitor C34 is grounded; The output pin of the electret microphone MIC2 is connected in parallel with a capacitor C42 and a diode E28, the other end of the capacitor C42 is grounded, and the input end of the diode E28 is grounded; The output pin of the negative terminal ‌MIC1-N of the microphone is connected to a capacitor C33, the other end of the capacitor C33 is connected in parallel with a resistor R20, a capacitor C41, and a diode E27, and the other ends of the resistor R20 and the capacitor C41 and the input end of the diode E27 are all grounded; The output pin of the audio signal port GPIO-12 is connected to a resistor R7, and the other end of the resistor R27 is connected in parallel to the output pin of the electret microphone MIC2; A selection switch is connected in parallel between the positive input end and the negative input end of the external microphone rod.

2. The minimalist circuit according to claim 1, characterized in that: The resistor R26 is 1K, the resistor R27 is 2K, and the capacitor C34 is 4.7uF.

3. The minimalist circuit according to claim 1, wherein: The capacitor C41 and the capacitor C42 are both 10nF.

4. The minimalist circuit according to claim 1, wherein: The capacitor C33 is 1uF, and the resistor R20 is 1K.

5. The minimalist circuit according to claim 1, characterized in that: The resistor R7 is 0R.

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