Voice gateway with built-in access control management function

Abstract

The utility model discloses a voice gateway with a built-in access control management function, which comprises a protocol chip, an interface circuit and a communication circuit, the interface circuit and the communication circuit are both connected onto the protocol chip, the interface circuit comprises a first connecting end and a second connecting end, and the first connecting end and the second connecting end are both connected to the protocol chip through corresponding matched resistors. The circuit is characterized in that a transient suppression diode is connected between the first connecting end and the second connecting end; or, the first connecting end is grounded through the transient suppression diode, and the second connecting end is grounded through the transient suppression diode; the transient suppression diode is located on the other side, corresponding to the protocol chip, of the matched resistor. According to the scheme, the protection effect of hot plugging can be further improved, and the service life is further prolonged.

Description

Technical Field

[0001] The utility model relates to a voice gateway, in particular to a voice gateway with a built-in access control management function. Background Art

[0002] The applicant's prior application, application number CN201921650765.4, is titled a utility model patent for a highway multi-service transmission system based on FPGA. The patent scheme discloses an RS485 interface circuit, and this scheme applies it to the access control interface. However, in actual use, the interface circuit still has room for improvement. For example, there is insufficient hot-swap protection at the external interface. During the installation and debugging process, hot-swap operations are inevitably required, so further improvement is needed. Utility Model Content

[0003] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a voice gateway with a built-in access control management function, which can further improve the protection effect of hot plugging and further increase the service life.

[0004] To achieve the above object, the utility model provides the following technical solution: a voice gateway with built-in access control management function, including a protocol chip, an interface circuit and a communication circuit both connected to the protocol chip, the interface circuit including a first connection end and a second connection end, and the first connection end and the second connection end are both connected to the protocol chip through corresponding matching resistors, characterized in that:

[0005] A transient suppression diode is further connected between the first connection terminal and the second connection terminal; or,

[0006] The first connection terminal is grounded via a transient suppression diode, and the second connection terminal is grounded via a transient suppression diode;

[0007] The transient suppression diode is located on the other side of the matching resistor corresponding to the protocol chip.

[0008] As a further improvement of the present invention, an optocoupler isolator is further connected between the first connection end and the second connection end and the corresponding matching resistor, and the electrical signals of the first connection end and the second connection end are transmitted through the optocoupler isolator.

[0009] As a further improvement of the utility model, the optocoupler isolator and the protocol chip are connected to the same power supply, and the power supply is connected in series with an NTC thermistor connected to the optocoupler isolator and the protocol chip, and a resistor with a fixed resistance is connected in parallel to the NTC thermistor; the NTC thermistor is arranged close to the protocol chip and the optocoupler isolator, and is used to change the resistance value in accordance with the operating temperature of the protocol chip and the optocoupler isolator.

[0010] As a further improvement of the present invention, the power supply is grounded via a capacitor.

[0011] The beneficial effects of the utility model include faster response speed to instantaneous high voltage, better protection effect, better protection effect to hot plugging, and increased circuit service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a circuit diagram of the first embodiment of the utility model;

[0013] Figure 2 This is a circuit structure diagram of the second embodiment of the utility model;

[0014] Figure 3 This is a circuit structure diagram of the third embodiment of the utility model;

[0015] Figure 4 This is a circuit structure diagram of the fourth implementation mode of the present utility model.

[0016] Figure numbers: 1. Protocol chip; 2. Interface circuit; 3. Communication circuit; 4. Transient suppression diode; 5. Optocoupler isolator; 6. NTC thermistor. DETAILED DESCRIPTION

[0017] The present invention will be further described below with reference to the embodiments shown in the accompanying drawings.

[0018] Reference Figure 1-4 As shown,

[0019] A voice gateway with a built-in access control management function comprises a protocol chip 1, an interface circuit 2 and a communication circuit 3 both connected to the protocol chip 1, the interface circuit 2 comprises a first connection end and a second connection end, and the first connection end and the second connection end are both connected to the protocol chip 1 through corresponding matching resistors;

[0020] A transient suppression diode 4 is further connected between the first connection terminal and the second connection terminal; or,

[0021] The first connection end is grounded through a transient suppression diode 4, and the second connection end is grounded through a transient suppression diode 4;

[0022] The transient suppression diode 4 is located on the other side of the matching resistor corresponding to the protocol chip 1 .

[0023] In specific applications, the interface circuit 2 is prone to hot plugging of the plug connector, and transient high voltage is prone to occur during the hot plugging process, which can easily affect the service life of other components. To this end, the first connection end and the second connection end are used to match the ends of the external plug connector for connection, that is, the exposed parts are optimized, and the optimization scheme can be selected from the following two schemes:

[0024] 1.Reference Figure 2 As shown, a transient suppression diode 4 is connected between the first connection end and the second connection end, that is, the two ends of the transient suppression diode 4 are respectively connected to the first connection end and the second connection end. At this time, if a transient high voltage appears at any end, the transient suppression diode 4 can be turned on to share the transient high voltage, so that the first connection end and the second connection end form a loop for protection.

[0025] 2.Reference Figure 1 , 3 As shown in , the first connection terminal and the second connection terminal are grounded through the transient suppression diode 4 respectively. At this time, the first connection terminal and the second connection terminal are relatively independent, and when a transient high voltage is generated at either end, the transient high voltage can be grounded, so the protection effect is better.

[0026] The transient suppression diode 4 of the above two solutions is located at the end of the matching resistor close to the port, so it is the first position to produce a protective effect, with a faster response speed and a better protective effect.

[0027] Further optimization, see Figure 3 An optocoupler isolator 5 is connected between the first connection end and the second connection end and the corresponding matching resistor, and the electrical signals of the first connection end and the second connection end are transmitted through the optocoupler isolator 5 .

[0028] The optocoupler isolator 5 can isolate the signal of the interface and make the signal waveform more stable, thereby avoiding the problem of voltage reduction and unstable electrical signal waveform caused by the length of the plug connector.

[0029] In the preferred embodiment, refer to Figure 3 As shown, the optocoupler isolator 5 is located between the matching resistor and the node of the transient suppression diode 4. At this time, the transient suppression diode 4 can also protect the optocoupler isolator 5, further improving the protection effect.

[0030] Of course, in certain cases, there may be an optical coupler isolator 5 that causes the matching resistor to be unable to match the plug connector. The optical coupler isolator 5 can also be set on the side of the matching resistor corresponding to the protocol chip 1, referring to Figure 4 shown.

[0031] Those skilled in the art may make a selection and implement it according to actual circuit requirements.

[0032] In addition, since the device may experience temperature changes during operation, large temperature changes will affect the stability of the signal. Therefore, this solution is further optimized. Figure 2As shown, the optocoupler isolator 5 and the protocol chip 1 are connected to the same power supply, and the power supply is connected in series with an NTC thermistor 6 connected to the optocoupler isolator 5 and the protocol chip 1, and a resistor with a fixed resistance is connected in parallel to the NTC thermistor 6; the NTC thermistor 6 is arranged close to the protocol chip 1 and the optocoupler isolator 5, and is used to change the resistance value in accordance with the operating temperature of the protocol chip 1 and the optocoupler isolator 5.

[0033] The resistance of the NTC thermistor 6 will change with the temperature. As a thermistor with a negative temperature coefficient, the resistance of NTC will decrease when the temperature rises. The effect of the resistance reduction is used in conjunction with a fixed resistance resistor to generate a relatively stable voltage and current, thereby generating a temperature compensation effect, thereby stabilizing the voltage and current of the power supply, and making the operation of the protocol chip 1 and the optocoupler isolator 5 more stable.

[0034] In a further configuration, the power supply is grounded via a capacitor. This capacitor allows the power supply to produce a more stable waveform and reduce the fluctuation of the electrical signal. Figure 1 shown.

[0035] The specific circuit can be implemented with reference to the scheme in the attached drawings. This scheme is mainly optimized for the interface, and other circuits do not involve improvement content. Those skilled in the art can implement it with reference to the scheme in the attached drawings or adopt other replaceable schemes. In the drawings of multiple implementation schemes provided in the attached drawings of this scheme, the circuits can be implemented in combination with each other.

[0036] The above is only a preferred embodiment of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A voice gateway with built-in access control management function, comprising a protocol chip, an interface circuit and a communication circuit both connected to the protocol chip, the interface circuit comprising a first connection terminal and a second connection terminal, and the first connection terminal and the second connection terminal are both connected to the protocol chip through corresponding matching resistors, characterized in that: A transient suppression diode is further connected between the first connection terminal and the second connection terminal; or, The first connection terminal is grounded via a transient suppression diode, and the second connection terminal is grounded via a transient suppression diode; The transient suppression diode is located on the other side of the matching resistor corresponding to the protocol chip.

2. The voice gateway with built-in access control management function according to claim 1, characterized in that: An optocoupler isolator is further connected between the first connection end and the second connection end and the corresponding matching resistor, and the electrical signals of the first connection end and the second connection end are transmitted through the optocoupler isolator.

3. The voice gateway with built-in access control management function according to claim 2, characterized in that: The optocoupler isolator and the protocol chip are both connected to the same power supply, and the power supply is connected in series with an NTC thermistor to the optocoupler isolator and the protocol chip, and a resistor with a fixed resistance is connected in parallel to the NTC thermistor; the NTC thermistor is arranged close to the protocol chip and the optocoupler isolator, and is used to change the resistance value in accordance with the operating temperature of the protocol chip and the optocoupler isolator.

4. The voice gateway with built-in access control management function according to claim 3, characterized in that: The power supply is grounded via a capacitor.

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