CN204350273U - Tone code product and tone code communication channel circuit - Google Patents

Abstract

The utility model discloses a kind of tone code product and tone code communication channel circuit.Wherein, this tone code communication channel circuit comprises: audio connector, identification circuit and tone code communication channel, the output of tone code communication channel is connected with the first pin of audio connector by the first capacitor, the first end of identification circuit is connected with the first pin of audio connector, the second end is connected with the second pin of audio connector, tone code communication channel circuit also comprises: first end is connected with the output of tone code communication channel, the electronic unit of the second end ground connection, wherein, the resistance of electronic unit is in preset range.

Description

Audio code products and audio code communication channel circuits

technical field

The utility model relates to the field of electronic technology, in particular to a sound code product and a sound code communication channel circuit.

Background technique

At present, audio connectors (also called audio interfaces) are divided into three-segment audio connectors and four-segment audio connectors, wherein the four-segment audio connectors are further divided into national standard four-segment interfaces and American standard four-segment interfaces. Pin 1 of the national standard four-segment interface (also called interface) is the left channel pin, pin 2 is the right channel pin, pin 3 is the microphone pin, pin 4 is the ground pin, and The pin setting method of the American standard four-segment interface is different. Among them, pin 1 is the left channel pin (also called the left channel interface), and pin 2 is the right channel pin (also called Right channel interface), pin 3 is the ground (GND) pin (also called the ground (GND) interface), pin 4 is the microphone (MIC) pin (also called the microphone (MIC) interface ). Take the national standard four-stage headphone plug as an example, the first end of the left channel speaker is connected to pin 1, and the second end is connected to pin 4; the first end of the right channel speaker is connected to pin 2, and the second end is connected to pin 2. The end is connected to pin 4; the first end of the microphone is connected to pin 3, and the second end is connected to pin 4. Audio code products generally use four-segment audio connectors, and output audio code signals to the inserted host through the MIC pins. Among them, the communication in which audio code products output audio code signals to the inserted host through the MIC pins is called audio code communication. channel. Fig. 1 is a circuit structure diagram of a sound code communication channel of a sound code product in the related art. As shown in Figure 1, in the related art, a sound code communication channel (EP_PIN4 of the upstream input sound code signal (AUpload1) of the main frame from the sound code product to the main frame, that is, from the sound code main product to the main frame and the sound code product inserted into the main frame The channel corresponding to the pin (pin 4 shown in Figure 1) connected to the microphone end behind the host, which can be called the audio code communication channel) is connected in series with a large resistance (generally 27 kilohms) (shown in Figure 1 is the equivalent resistance R2 of the electronic component), after the audio code product connector (EarphonePlus) is inserted into the host (for example, a computer or mobile terminal), the host pair is connected between EP_PIN3 and EP_PIN4 The identification circuit Rmic is used for identification to realize the detection of whether the earphones match.

In related technologies, audio code products generally use Frequency-shift keying (FSK) data. When the audio code product interacts with the host, the output voltage of the audio code product varies in magnitude before and after the host is connected. It will affect the signal quality from the audio code product to the host, the greater the amplitude of the change, the worse the communication quality. In the circuit structure shown in Figure 1, the output end of the audio code communication channel is connected to the audio connector through a capacitor (C2). After the audio code product is inserted into the host, the identification circuit and The connected host is connected in parallel and connected in series with R2. Since the resistance of R2 and the identification circuit are both large, after the host is connected, the signal amplitude from the audio code product to the host is equivalent to that of the audio code product when the host is connected. The resistance value of the resistor is determined, the host with a larger equivalent resistance has a larger signal amplitude, and the host with a smaller equivalent resistance has a smaller signal amplitude. In practical applications, there are various types of hosts. Some hosts have a low equivalent resistance value when accessing audio code products, and some hosts have high equivalent resistance resistance when accessing audio code products. The signal amplitude from the product to the host is uncontrollable, and, for hosts whose equivalent resistance resistance is too low or too high for accessing the audio code product, the signal amplitude from the audio code product to the host is too small or too large, which may exceed The identification range of the host is limited, thereby limiting the range of hosts compatible with audio code products.

Utility model content

In order to solve the problem that the signal amplitude from the sound code product to the host is uncontrollable, the utility model provides a sound code product and a sound code communication channel circuit.

According to one aspect of the present invention, a voice code communication channel circuit is provided. The audio code communication channel circuit includes: an audio joint, an identification circuit and an audio code communication channel, the output end of the audio code communication channel is connected to the first pin of the audio joint through a first capacitor, and the first end of the identification circuit is connected to the audio joint. The first pin is connected, the second end is connected to the second pin of the audio connector, and the sound code communication channel circuit also includes: the first end is connected to the output end of the sound code communication channel, and the second end is grounded. Electronic components, wherein, The resistance value of the electronic part is within the preset range.

Optionally, the electronic component includes a plurality of electronic components connected in series and/or in parallel.

Optionally, the electronic component includes a pull-down resistor.

Optionally, the number of electronic components is 1, and the voice code communication channel includes a path corresponding to a MIC pin of the voice code product.

Optionally, the electronic component includes a first electronic component and a second electronic component, and the audio code communication channel includes a first audio code communication channel corresponding to the MIC pin of the audio code product and a GND pin corresponding to the audio code product. The second audio code communication channel, the first end of the first electronic component is connected to the output end of the first audio code communication channel, the second end is grounded, and the first end of the second electronic component is connected to the output of the second audio code communication channel terminal and the second end are grounded, the output end of the first audio code communication channel is connected to the first pin of the audio connector through the first capacitor, and the output end of the second audio code communication channel is connected to the second tube of the audio connector through the second capacitor pin connection.

Optionally, the circuit further includes: an analog switch, connected between the first electronic component and the output end of the first audio code communication channel, and between the second electronic component and the output end of the second audio code communication channel, wherein the analog switch It is normally open and closed after the audio code product is connected to the host.

Optionally, the sound code communication channel circuit also includes: a first analog switch connected between the output end of the first sound code communication channel and the first electronic component; a second analog switch connected to the second sound code communication channel Between the output end and the second electronic component, wherein the first analog switch and the second analog switch are normally open and closed after the voice code product is connected to the host.

Optionally, the preset range is: 100-999 ohms.

Optionally, the preset range is 270-510 ohms.

According to another aspect of the present invention, a sound code product is provided, which includes the above sound code communication channel circuit.

As can be seen from the technical scheme provided by the above-mentioned utility model, the audio code communication channel circuit provided by the utility model is connected to an electronic component whose resistance value of grounding is within a preset range at the output end of the audio code communication channel, so that the audio code communication channel circuit can be controlled. The resistance value output by the communication channel can further control the signal amplitude output by the audio code product within a certain range after the audio code product is connected to the host, which improves the host range compatible with the audio code product.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention , for those skilled in the art, other drawings can also be obtained based on these drawings without creative work.

Fig. 1 is the circuit structural diagram of the sound code communication channel circuit of a kind of sound code product in the related art;

Fig. 2 is the structural representation of the sound code communication channel circuit that the utility model embodiment one provides;

Fig. 3 is a schematic structural diagram of an optional audio code communication channel circuit provided by Embodiment 1 of the present invention;

FIG. 4 is a schematic structural diagram of another optional audio code communication channel circuit provided by Embodiment 1 of the present invention;

Fig. 5 is a schematic structural diagram of another optional audio code communication channel circuit provided by Embodiment 1 of the present invention;

Fig. 6 is a schematic structural diagram of a sound code communication channel circuit provided by Embodiment 2 of the present invention;

Fig. 7 is a schematic structural diagram of an optional audio code communication channel circuit provided by Embodiment 2 of the present invention;

Fig. 8 is a schematic structural diagram of another optional audio code communication channel circuit provided by Embodiment 2 of the present invention;

Fig. 9 is the circuit structural diagram of the sound code communication channel circuit that the utility model embodiment three provides;

Fig. 10 is the circuit structural diagram of the sound code communication channel circuit that the utility model embodiment four provides;

Fig. 11 is the circuit structural diagram of the sound code communication channel circuit that the utility model embodiment five provides;

Fig. 12 is a schematic structural diagram of the audio code product provided by Embodiment 6 of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention are clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. . Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present utility model.

Embodiment one

This embodiment provides a sound code communication channel circuit, and FIG. 2 is a schematic structural diagram of the sound code communication channel circuit provided by this embodiment.

As shown in Figure 2, the audio code communication channel circuit provided by the present embodiment mainly includes: audio connector 200, identification circuit 202, audio code communication channel 204 and the first end is connected with the output end of the audio code communication channel, and the second end is grounded The electronic component 206, wherein, the resistance value of the electronic component 206 is within a preset range, the output end of the voice code communication channel 204 is connected to the first pin of the audio connector 200 through the first capacitor 201, and the first end of the identification circuit 202 It is connected to the first pin of the audio connector 200 , and the second end is connected to the second pin of the audio connector 200 .

In this embodiment, the identification circuit 202 is connected between the two channels of the audio code product. After the audio code product is inserted into the host, the host will identify it through the identification circuit 202 to detect whether the earphones match. The audio code communication channel 204 is used to transmit the uplink FSK encoded audio code signal from the audio code product to the host, and the output end of the audio code communication channel 204 is connected to the audio connector 200 of the audio code product through the first capacitor 201 . Electronics 206 are connected at the output of the audio code communication channel.

In practical applications, the audio connector 200 is used to connect to an external host, and may include a plurality of pins, for example, left and right channel pins, a microphone (MIC) pin, and a ground (GND) pin.

In practical applications, after the audio connector 200 is connected to the host, in addition to the left and right channel pins of the audio, one of the other two pins of the audio connector 200 is a microphone (MIC) pin (that is, when the audio connector 200 is inserted into the After the host, this pin is connected to the MIC interface of the host), and the other is a ground pin (that is, after the audio connector 200 is inserted into the host, this pin is grounded). In an optional implementation manner of the embodiment of the present invention, the channel corresponding to the MIC pin is the audio code product communication channel 204, and the output end of the audio code communication channel 204 can be connected to the MIC pin through a capacitor 201. After being inserted into the host, the uplink audio code data output by the audio code product is output from the MIC interface to the host through the audio code product communication channel 204 .

In an optional implementation of this embodiment, the electronic component connected to the voice code communication channel 204 can be equivalent to an electronic component with a large resistance value, and the first end of the electronic component 206 is connected to the electronic component with a large resistance value. The output terminals are electrically connected.

In an optional implementation manner of the embodiment of the present invention, the electronic component 206 may be one electronic component, or may include a plurality of electronic components connected in series (as shown in FIG. 3 , two electronic components connected in series are shown in the figure), or, It can also include a plurality of electronic components connected in parallel (Fig. 4, two parallel electronic components are shown in the figure), or a plurality of series and parallel electronic components (Fig. The electronic components connected in parallel are connected in series with one electronic component), the specific embodiments of the present invention are not limited, as long as the final equivalent resistance is within the preset range mentioned above.

In an optional implementation of this embodiment, the electronic component 206 may be a pull-down resistor, of course, it is not limited thereto, and the electronic component 206 may also be an electronic component of other forms, as long as its resistance value is less than a predetermined value and does not It is enough to affect the function of other components on the circuit.

In an optional embodiment, when the electronic component 206 is a pull-down resistor, the electronic component 206 can be a resistor with a small resistance, or it can also be a plurality of small resistance circuits connected in parallel (that is, the electronic component in FIG. 3 It is a small resistance resistor), or, it can also be a plurality of small resistance resistors in series (that is, the electronic components in Figure 4 are small resistance resistors), or, it can also be a plurality of components connected in series and then connected in parallel with other components (That is, the electronic components in FIG. 5 are small resistance resistors), as long as the final total equivalent resistance can meet the requirements (that is, within the above-mentioned preset range), the implementation form is not limited.

Optionally, the preset range in the embodiment of the present invention is 100-999 ohms, and optionally, the preset range is 270-510 ohms. In the specific implementation process, the resistance value of the electronic component 206 can be based on the requirements for the final output voltage of the audio code product (that is, the voltage range that the host can recognize), the resistance value of the identification circuit 202, and the electronic components contained in the audio code communication channel 204. The resistance value of the element and the voltage value of the signal input terminal of the voice code communication channel are determined.

For example, assuming that the resistance value of the equivalent resistance in the audio code communication channel is 27 kilohms, when the audio code product transmits signals to the host, the voltage value of the audio code communication channel input terminal is 3.3V, and the resistance value of the identification circuit 202 is 10 kilohm In Europe, it is required that the signal from the sound code product to the host reaches the voltage range of 9 ~ 120mV. but:

(1) If the resistance value of the electronic part 206 is 100 ohms, then after the sound code product is inserted into the main frame, the electronic part 206, the recognition circuit 202 and the input end of the main frame are connected in parallel, and then connected with the electronic components in the sound code communication channel In series, if the resistance value of the equivalent resistance input by the host is greater than 100 ohms, the resistance value after the parallel connection of the electronic component 206, the identification circuit 202 and the input end of the host is about 100 ohms, and the voltage at the input end of the host is Vmic=3.3*( 100/(27000+100)≈12mV. If the resistance value of the equivalent resistance input by the host is less than 100 ohms (assumed to be 80 ohms), the resistance value after the parallel connection of the electronic component 206, the identification circuit 202 and the input terminal of the host is about It is 80 ohms, and the voltage at the input terminal of the host is Vmic=3.3*(80/(27000+80)≈9.7mV, which meets the requirements and the host can normally recognize the signal output by the audio code product.

(2) If the resistance value of the electronic part 206 is 999 ohms, then after the sound code product is inserted into the main frame, the electronic part 206, the recognition circuit 202 and the input end of the main frame are connected in parallel, and then connected with the electronic components in the sound code communication channel In series, if the resistance value of the equivalent resistance input by the host is greater than 999 ohms, the resistance value after the parallel connection of the electronic component 206, the identification circuit 202 and the input end of the host is about 999 ohms, and the voltage at the input end of the host is Vmic=3.3*( 999/(27000+999)≈117.7mV. If the resistance value of the equivalent resistance input by the host is less than 999 ohms (assumed to be 150 ohms), the resistance value after the parallel connection of the electronic component 206, the identification circuit 202 and the input terminal of the host It is about 150 ohms, and the voltage at the input terminal of the host is Vmic=3.3*(150/(27000+150)≈18mV, which meets the demand.

(3) If the resistance value of the electronic part 206 is 270 ohms, then after the sound code product is inserted into the main frame, the electronic part 206, the identification circuit 202 and the main frame input end are connected in parallel, and then connected with the electronic components in the sound code communication channel In series, if the resistance value of the equivalent resistance input by the host is greater than 270 ohms, the resistance value after the parallel connection of the electronic component 206, the identification circuit 202 and the input end of the host is about 270 ohms, and the voltage at the input end of the host is Vmic=3.3*( 270/(27000+270)≈32mV. If the resistance value of the equivalent resistance input by the host is less than 270 ohms (assumed to be 200 ohms), the resistance value after the parallel connection of the electronic component 206, the identification circuit 202 and the input terminal of the host is about It is 200 ohms, and the voltage at the input terminal of the host is Vmic=3.3*(200/(27000+200)≈24.3mV, which meets the demand.

(4) If the resistance value of the electronic part 206 is 400 ohms, then after the sound code product is inserted into the main frame, the electronic part 206, the identification circuit 202 and the main frame input end are connected in parallel, and then connected with the electronic components in the sound code communication channel In series, if the resistance value of the equivalent resistance input by the host is greater than 400 ohms, the resistance value after the parallel connection of the electronic component 206, the identification circuit 202 and the input end of the host is about 400 ohms, and the voltage at the input end of the host is Vmic=3.3*( 400/(27000+400)≈48.1mV. If the resistance value of the equivalent resistance input by the host is less than 400 ohms (assumed to be 200 ohms), the resistance value after the parallel connection of the electronic component 206, the identification circuit 202 and the input terminal of the host It is about 200 ohms, and the voltage at the input terminal of the host is Vmic=3.3*(200/(27000+200)≈24.3mV, which meets the demand.

(5) If the resistance value of the electronic part 206 is 510 ohms, then after the sound code product is inserted into the main frame, the electronic part 206, the recognition circuit 202 and the main frame input end are connected in parallel, and then connected with the electronic components in the sound code communication channel In series, if the resistance value of the equivalent resistance input by the host is greater than 510 ohms, the resistance value after the parallel connection of the electronic component 206, the identification circuit 202 and the input end of the host is about 510 ohms, and the voltage at the input end of the host is Vmic=3.3*( 510/(27000+510)≈61.1mV. If the resistance value of the equivalent resistance input by the host is less than 510 ohms (assumed to be 200 ohms), the resistance value after the parallel connection of the electronic component 206, the identification circuit 202 and the input terminal of the host It is about 200 ohms, and the voltage at the input terminal of the host is Vmic=3.3*(200/(27000+200)≈24.3mV, which meets the demand.

Through the sound code communication channel circuit provided by this embodiment, by connecting the grounded electronic components at the output end of the sound code communication channel, the resistance value output by the sound code communication channel can be reduced, so that hosts with different input resistance values can be connected The amplitude change is controlled within a certain range.

Embodiment two

Because in practice, the positions of the MIC interface are different in different standards, therefore, in order to be compatible with the four-segment audio interface of different standards on the host, in the embodiment of the present invention, the MIC pin and the GND pin correspond to Passage is all regarded as audio code communication channel, as shown in Figure 6, in the present embodiment, audio code product communication channel circuit comprises audio code communication channel 204-1 and audio code communication channel 204-2, in audio code communication channel 204- 1 and the output end of the sound code communication channel 204-2 are respectively connected to a grounding electronic component, i.e. the electronic component 206-1 and the electronic component 206-2, and the output ends of the sound code communication channel 204-1 and the sound code communication channel 204-2 pass through respectively Capacitors 201 and 203 are connected to the MIC pin and the GND pin. In the specific implementation process, the output ends of the audio code communication channel 204-1 and the audio code communication channel 204-2 can also be reversed through the pins connected to the capacitors 201 and 203 respectively, that is, the output end of the audio code communication channel 204-1 passes through The capacitor 201 is connected to the GND pin, and the output terminal of the voice code communication channel 204-2 is connected to the MIC pin through the capacitor 203 . The specific embodiment of the utility model is not limited.

Similar to the first embodiment above, optionally, the electronic components 206-1 and 206-2 in this embodiment may be one electronic component, or multiple electronic components connected in series, in parallel, or first in series and then in parallel. Examples are not limited.

Adopt the structure shown in Fig. 6, at the instant when the audio code product is inserted into the host, the host MIC has electronic component 206-1 and electronic component 206-2 paths to the ground, due to the path resistance of electronic component 206-1 and electronic component 206-2 Smaller, the channel is characterized by capacitance, which affects the earphone detection after the audio code product is inserted into the host, thereby affecting the earphone recognition.

Therefore, in an optional implementation of this embodiment, the optional audio code communication channel adds an analog switch 208 on the basis of the audio code communication channel circuit shown in Figure 6, as shown in Figure 7, the analog The switch 208 is connected between the output end of the electronic component 206-1 and the audio code communication channel 204-1, and the electronic component 206-2 and the audio code communication channel 204-2, for controlling the electronic component 206-1 and the electronic component 206 -2 access. In this embodiment, the analog switch 208 is normally open, and after the voice code product is inserted into the host, the analog switch 208 is closed to connect the electronic component 206 into the circuit when the input is at a high level.

It should be noted that although the drawings only show that the analog switch 208 is added on the basis of FIG. An analog switch 208 is added between the code communication channels 204. For the case of multiple electronic components 206, one multi-contact modular switch can be used, or multiple modular switches can be used respectively, which is not limited in this embodiment.

In addition, the analog switch 208 in this embodiment can be realized by using a crystal diode, a MOS transistor (metal (metal)-oxide (oxid)-semiconductor (semiconductor) field effect transistor), etc., which is not limited in this embodiment, as long as the module The switch can realize the above-mentioned normal disconnection, and it can be closed after the audio code product is inserted into the host.

In addition, the analog switch 208 in this embodiment can be a multi-point control switch (as shown in FIG. 7 ), or two analog switches can also be set to control the access of the electronic components 206-1 and 206-2 respectively. As shown in FIG. 8, the analog switch 208-1 controls the access of the electronic component 206-1, and the analog switch 208-2 controls the access of the electronic component 206-2.

In the above optional embodiment, due to the disconnected state of the module switch 208 under normal conditions, the electronic component 206 will not be connected at the moment when the host is inserted, thereby avoiding the capacitive characteristics of the audio code communication channel at the moment of access, Furthermore, it will not affect the detection of the sound code product after the sound code product is inserted into the host, thereby improving the reliability of recognition.

It should be noted that the audio code communication channels 204 and electronic components 206 described in the first embodiment are also applicable to the audio code communication channels 204-1 and 204-2 and the electronic components 206-1 in this embodiment. and 206-2, details will not be repeated here.

The following embodiments will take the electronic component 206 as a pull-down resistor, and the pull-down resistor is an independent small resistor as an example, and illustrate the technical solutions provided by the implementation of the utility model through specific examples.

Embodiment three

This embodiment provides a sound code communication channel circuit, and FIG. 9 is a circuit structural diagram of the sound code communication channel circuit in this embodiment. As shown in Figure 9, in the present embodiment, the audio code product connector (EarphonePlus) has 4 pins, which are respectively:

Pin 1: <LEFT (left)><G>, connected to EP_L channel;

Pin 2: <RIGHT (right)><R>, connected to EP_R channel;

Pin 3: <GND><B>, connect to ground EP_PIN3 channel; and

Pin 4: <MIC><GD>, connected to the audio code communication channel EP_PIN4 (in practical applications, for different standards, the positions of the <MIC> pin and <GND> pin can be reversed, that is, pin 3 is < MIC> pin, pin 4 is <GND> pin, as shown in Figure 10).

In addition, the audio code communication channel EP_PIN4 is provided with an equivalent resistance R2 and a DC blocking capacitor C2. Between the effective resistor R4 and the capacitor C2) the pull-down resistor R4 is connected, and an identification circuit is provided between EP_PIN3 and EP_PIN4. It should be noted that, for convenience, the equivalent resistance of the identification circuit 202 ie Rmic is drawn in the figure, and the specific structure of the identification circuit 202 is not drawn. In practical applications, the identification circuit 202 can adopt the structure of the identification circuit in the existing audio code product, or simply modify the existing identification circuit, as long as it can detect the earphone when the audio code product is inserted into the host That is, the specific structure of the embodiment of the present invention is not limited.

In this embodiment, the resistance value of R4 is 470 ohms, and the resistance values of resistors R1 and R2 are 27 kilohms.

In this embodiment, after the audio code product is inserted into the host, the audio code input signal (AUpload1) is input from the input ends of the parallel EP_PIN3 and EP_PIN4 paths, and because the pin 3 is grounded, the audio code signal passes through the audio code communication channel EP_PIN4 input to the host. After the equivalent resistance connected to the host, the identification circuit Rmic and the pull-down resistor R4 are connected in parallel, they are connected in series with R2. Assuming that the equivalent resistance connected to the host is 600 ohms, the resistance of the identification circuit Rmic is 10K ohms, and the voltage at the input terminal of EP_PIN4 is 3.3 volts, since the resistance value of the R4 resistor (470 ohms) is the smallest among the three parallel channels, Therefore, the resistance value of the parallel connection of the equivalent resistance connected to the host, the identification circuit Rmic and the pull-down resistor R4 is about 470 ohms, and the voltage value of the input terminal of the host is:

Vmic＝3.3*(470/(27000+470)≈56.6mV

It falls within the signal amplitude range of 9~120mV that the host can recognize.

It can be seen that by inserting a pull-down resistor at the output end of the audio code communication channel, the amplitude range of the audio code signal input to the host can be controlled, and the compatible host range of the audio code product can be improved.

Embodiment four

This embodiment provides a sound code communication channel circuit, and FIG. 10 is a circuit structural diagram of the sound code communication channel circuit in this embodiment. As shown in Figure 10, the difference between the sound code communication channel circuit in this embodiment and the sound code communication channel circuit of embodiment three is that EP_PIN3 and EP_PIN4 corresponding to pins 3 and 4 (that is, in this embodiment, EP_PIN3 and EP_PIN4 are all regarded as voice code communication channels, shown in Figure 10 are EP_PIN3 and EP_PIN4's equivalent resistance R1 and R2) the upstream output terminals are all connected to the pull-down resistance (ie R4 and R5), so that it can be compatible with different standards .

In this embodiment, the resistance value of R4 and R5 is 470 ohms, and the resistance value of resistors R1 and R2 is 27 kilohms.

In this embodiment, after the audio code product is inserted into the host, the audio code input signal (AUpload1) is input from the input terminals of the parallel EP_PIN3 and EP_PIN4 channels. As shown in Figure 10, assuming that the pin connected to the MIC interface of the host is pin 3, and its corresponding channel is EP_PIN3, then after the audio code product is inserted into the host, switch S2 is on GFIO (General-Function Input/Output Ports, general-purpose Under the action of the input level of the I/O port), pin 4 is grounded, and the equivalent resistance connected to the host, the identification circuit Rmic and the pull-down resistor R5 are connected in parallel and then connected in series with R5.

Assuming that the equivalent resistance connected to the host is 200 ohms, the resistance of the identification circuit Rmic is 10K ohms, and the voltage at the input terminal of EP_PIN3 is 3.3 volts, since the resistance value (200 ohms) of the equivalent resistance connected to the host is connected in three parallel connections The resistance value in the channel is the smallest. Therefore, the resistance value of the parallel connection of the equivalent resistance connected to the host, the identification circuit Rmic and the pull-down resistor R5 is about 200 ohms, and the voltage value of the input terminal of the host is:

Vmic＝3.3*(200/(27000+200)≈24.3mV

It falls within the signal amplitude range of 9~120mV that the host can recognize.

It can be seen that by connecting the pull-down resistor at the output end of the audio code communication channel EP_PIN3, the signal amplitude range of the audio code signal input to the host can be controlled, and the range of hosts compatible with audio code products can be increased.

Moreover, it should be noted that although the above description is made with the pin connected to the MIC interface of the host as pin 3, for the case where the pin connected to the MIC interface of the host is pin 4, the pin connected to the MIC interface of the host is The pin 3 is similar, and the only difference is that the pull-down resistor for accessing the voice code communication channel is R4. Since the output terminal of the audio code communication channel EP_PIN4 is also connected to the pull-down resistor R4, therefore, for the case where the channel corresponding to the interface of the host MIC is EP_PIN4, the signal amplitude range of the audio code signal input to the host can also be controlled.

Embodiment five

In Embodiment 4, at the moment when the audio code product is inserted into the host, the host MIC has C1, R4, R5, and C2 paths to the ground. Since the resistance values of R4 and R5 are small, this path is characterized by capacitance, thereby affecting the insertion of the audio code product. The headphone detection behind the host affects the headphone recognition. Therefore, this embodiment is improved on the basis of the fourth embodiment, and a switch is added between the pull-down resistor and the output terminal of the voice code communication channel.

Fig. 11 is the circuit structure diagram of the sound code communication channel in the present embodiment, as shown in Fig. 11, the sound code communication channel in the present embodiment has increased an analog switch S1 on the basis of embodiment four, and this switch is used for Connect the pull-down resistor.

In the circuit shown in FIG. 11 , when the audio code product is inserted into the host, the analog switch S1 is turned on, and the identification circuit Rmic between EP_PIN3 and EP_PIN4 performs identification. When the recognition circuit Rmic recognizes that the audio code product has data interaction with the host, the switch S1 is closed under the action of the level input by GFIO, so that the pull-down resistors R4 and R5 are connected. At this time, it not only reduces the output resistance of the audio code product port, but also avoids the moment when the audio code product is inserted into the host, because the host MIC has C1, R4, R5, and C2 paths to the ground, which are characterized by capacitance and affect the audio code. The earphone detection after the product is inserted into the host affects the earphone recognition problem.

It should be noted that although the embodiment described above adds the switch S1 on the basis of the fourth embodiment, it is not limited thereto, and the switch S1 may also be added on the basis of the third embodiment. In this case, S1 is set between R4 and the output port of the vocoder communication channel to control the access of R4.

It should be noted that, although the above-mentioned embodiments 3 to 5 are described by taking the electronic component 206 as a pull-down resistor as an example, it is not limited thereto. In practical applications, the electronic component 206 can also be other electronic components. For example, the resistance value is between As long as the resistance value of the indicator lights in the above-mentioned preset range is within the above-mentioned preset range and does not affect the normal operation of other components in the circuit, it is sufficient.

Embodiment six

This embodiment provides a phonetic code product.

Fig. 12 is the structural representation of the sound code product of the present embodiment, as shown in Figure 12, this sound code product comprises sound code communication channel circuit, and this sound code communication channel circuit can comprise any embodiment in above-mentioned embodiment one to five Audio code communication channel circuit. In addition, optional implementation manners described in any of the first to fifth embodiments may be adopted.

Through the sound code product provided by this embodiment, by connecting the pull-down resistor at the output end of the sound code communication channel of the sound code product, the resistance value output by the sound code product can be reduced, and then the signal amplitude input to the host can be controlled within a certain range Improve the compatibility of audio code products.

In the description of the present utility model, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a flexible connection. Detachable connection, or integral connection; it can be mechanical connection or electrical connection; it can be direct connection or indirect connection through an intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present utility model in specific situations.

In the description of this specification, descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structures, materials or features are included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above-mentioned embodiments are exemplary and cannot be construed as limitations of the present invention. The above-mentioned embodiments can be changed, modified, replaced and modified within the scope of the present utility model under the principle and purpose. The scope of the invention is defined by the appended claims and their equivalents.

Claims (13)

1. A kind of sound code communication channel circuit, comprising: audio joint, identification circuit and sound code communication channel, the output end of described sound code communication channel is connected with the first pin of audio joint by the first capacitor, described identification circuit The first end of the first end is connected to the first pin of the audio connector, and the second end is connected to the second pin of the audio connector. It is characterized in that the audio code communication channel circuit further includes: the first end is connected to the The output end of the voice code communication channel is connected to an electronic component whose second end is grounded, wherein the resistance value of the electronic component is within a preset range, and the preset range includes: 100-999 ohms. 2. The voice code communication channel circuit according to claim 1, characterized in that, the electronic components comprise a plurality of electronic components connected in series and/or in parallel. 3. The voice code communication channel circuit according to claim 1 or 2, characterized in that, the electronic components include pull-down resistors. 4. The audio-code communication channel circuit according to claim 3, wherein the number of said electronic components is 1, and said audio-code communication channel includes a path corresponding to a microphone MIC pin of an audio-code product. 5. The audio-code communication channel circuit according to claim 1 or 2, wherein the number of said electronic components is 1, and said audio-code communication channel includes a path corresponding to a microphone MIC pin of an audio-code product. 6. The sound code communication channel circuit according to claim 3, characterized in that, the electronic components include a first electronic component and a second electronic component, and the sound code communication channel includes a signal corresponding to the MIC pin of the sound code product. The first audio code communication channel and the second audio code communication channel corresponding to the ground GND pin of the audio code product, the first end of the first electronic component is connected to the output end of the first audio code communication channel, The second end is grounded, and the first end of the second electronic component is connected to the output end and the second end of the second audio code communication channel, and the output end of the first audio code communication channel is connected to the first capacitor through the first capacitor. The first pin of the audio connector is connected, and the output end of the second vocoder communication channel is connected to the second pin of the audio connector through a second capacitor. 7. The sound code communication channel circuit according to claim 1 or 2, characterized in that, the electronic components include a first electronic component and a second electronic component, and the sound code communication channel includes a MIC tube connected to the sound code product. The first audio code communication channel corresponding to the pin and the second audio code communication channel corresponding to the ground GND pin of the audio code product, the first end of the first electronic component is connected to the output of the first audio code communication channel end and the second end are grounded, the first end of the second electronic component is connected to the output end of the second audio code communication channel, and the second end is grounded, and the output end of the first audio code communication channel passes through the first The capacitor is connected to the first pin of the audio connector, and the output end of the second vocoder communication channel is connected to the second pin of the audio connector through the second capacitor. 8. sound code communication channel circuit according to claim 6, is characterized in that, described circuit also comprises: Analog switch, is connected in described first electronic component and the output end of described first sound code communication channel, and Between the second electronic component and the output end of the second audio-code communication channel, wherein the analog switch is normally open and closed after the audio-code product is connected to the host. 9. sound code communication channel circuit according to claim 7, is characterized in that, described circuit also comprises: Analog switch, is connected in described first electronic component and the output end of described first sound code communication channel, and Between the second electronic component and the output end of the second audio-code communication channel, wherein the analog switch is normally open and closed after the audio-code product is connected to the host. 10. sound code communication channel circuit according to claim 6, is characterized in that, described sound code communication channel circuit also comprises: the first analog switch, is connected in the output end of described first sound code communication channel and described Between the first electronic components; the second analog switch, connected between the output end of the second audio code communication channel and the second electronic component, wherein the first analog switch and the second analog switch It is normally open and closed after the audio code product is connected with the host. 11. sound code communication channel circuit according to claim 7, is characterized in that, described sound code communication channel circuit also comprises: the first analog switch, is connected in the output end of described first sound code communication channel and described Between the first electronic components; the second analog switch, connected between the output end of the second audio code communication channel and the second electronic component, wherein the first analog switch and the second analog switch It is normally open and closed after the audio code product is connected with the host. 12. The audio code communication channel circuit according to claim 1, wherein the preset range is 270-510 ohms. 13. A sound code product, characterized in that it comprises the sound code communication channel circuit according to any one of claims 1 to 12.