CN219554090U

CN219554090U - Set top box interface protection device

Info

Publication number: CN219554090U
Application number: CN202320286673.2U
Authority: CN
Inventors: 李洪斌; 黄倩; 徐健; 朱思萌
Original assignee: Sichuan Jiuzhou Electronic Technology Co Ltd
Current assignee: Sichuan Jiuzhou Electronic Technology Co Ltd
Priority date: 2023-02-22
Filing date: 2023-02-22
Publication date: 2023-08-18
Anticipated expiration: 2033-02-22

Abstract

The utility model discloses a set top box interface protection device, which comprises a set top box main board and an external interface arranged on the set top box main board, wherein the external layer ground of the external interface is connected with the main board ground of the set top box main board, an isolation area is arranged between the external layer ground of the external interface and the main board ground of the set top box main board, and the external layer ground of the external interface is connected with the main board ground of the set top box main board in the isolation area through a protection isolation line; the utility model can greatly reduce the combustion faults of the set top box and the television.

Description

Set top box interface protection device

Technical Field

The utility model relates to the technical field of set top boxes, in particular to a set top box interface protection device.

Background

The set top box product is connected to a television through an HDMI interface or an AV interface, the RF interface is connected to a cable television signal line, and signals are decoded and output to the television, so that a user can watch cable television signals. Because the television and the cable television signal wires are likely to leak electricity, the household equipment of individual users is not effectively connected to the ground, the leakage electricity can reach the main board ground of the set top box through the outer ground wire of the HDMI wire or the AV wire, and if the leakage current is large, the wires can heat and even burn, so that the set top box and the television are burned, combustion accidents exist in the market each year, and potential safety hazards are brought to the users.

As shown in fig. 1, fig. 1 is a schematic diagram of a connection structure between an external layer ground 2 of an external interface 1 of an existing set top box and a main board ground 3 of the set top box, and as can be seen from fig. 1, the external layer ground of the HDMI and AV interfaces are directly connected with the main board ground of the set top box in a large area, so that no protective effect is provided for leakage of external equipment, and serious potential safety hazards exist.

Disclosure of Invention

In order to solve the problems in the prior art, the utility model aims to provide the set top box interface protection device which can greatly reduce the combustion faults of the set top box and the television.

In order to achieve the above purpose, the utility model adopts the following technical scheme: the set top box interface protection device comprises a set top box main board and an external interface arranged on the set top box main board, wherein the outer layer ground of the external interface is connected with the main board ground of the set top box main board, an isolation area is arranged between the outer layer ground of the external interface and the main board ground of the set top box main board, and the outer layer ground of the external interface is connected with the main board ground of the set top box main board in the isolation area through a protection isolation line.

As a further improvement of the utility model, the width of the connection between the two ends of the protective isolation line and the outer layer ground and the main board ground is larger than the width of the middle of the protective isolation line.

As a further improvement of the utility model, the width of the two ends of the protective isolation line is 0.4mm-0.6mm, and the width of the middle of the protective isolation line is 0.14mm-0.16mm.

As a further improvement of the present utility model, the external interface is one or more of an HDMI interface, an AV interface, and an RF interface.

The beneficial effects of the utility model are as follows:

according to the utility model, the external ground of the external interfaces such as the HDMI interface and the AV interface is isolated from the main board ground of the main board of the set top box, when the external equipment has electric leakage, the external ground current of the wire rod of the protection isolation line reaches a certain degree, and the external ground and the main board ground are fused, so that the current transmission path is cut off, and the set top box and the television are prevented from being burnt.

Drawings

Fig. 1 is a schematic diagram of a connection structure between an external layer ground of an external interface of a set top box and a main board ground of the set top box in the prior art;

fig. 2 is a schematic diagram of a connection structure between an external ground of an external interface of a set-top box and a main board ground of the set-top box in an embodiment of the present utility model.

Reference numerals:

1. the external interface, 2, outer layer ground, 3, main board ground, 4, isolation area, 5, protection isolation line.

Detailed Description

Embodiments of the present utility model will be described in detail below with reference to the accompanying drawings.

Examples

As shown in fig. 2, a set-top box interface protection device comprises a set-top box main board and an external interface 1 arranged on the set-top box main board, wherein an outer layer ground 2 of the external interface 1 is connected with a main board ground 3 of the set-top box main board, an isolation area 4 is arranged between the outer layer ground 2 of the external interface 1 and the main board ground 3 of the set-top box main board, and the outer layer ground 2 of the external interface 1 is connected with the main board ground 3 of the set-top box main board in the isolation area 4 through a protection isolation line 5.

This embodiment is further described below:

the detailed relation of the current carrying capacity of the PCB conductor, the cross-sectional area, the current and the temperature rise is given by referring to the IPC-2152,Standard for Determining Current Carrying Capaci ty in Pr inted Circui t Board Des ign document. Using the ondardon equation, I is the fuse current; t is time; a is the cross-sectional area:

it can be calculated that a PCB trace with copper thickness of 1OZ and line width of 0.18mm has an operating current of 1A and rated current of 1.3A, and can be quickly fused within 20ms when the fusing current is 13A.

Based on the theoretical basis, the embodiment utilizes the characteristic of large-current fusing of the PCB wiring, and the scheme is as follows: the external ground 2 (the external ground wire of HDMI and AV wire) of the external interface 1 is isolated from the main board ground 3 through an isolation area 4 and is connected with the main board ground 3 through a tiny protection isolation wire 5, the protection isolation wire 5 is about 0.15mm (the normal signal current of HDMI and AV wire can normally pass through 1A current and is less than 100mA, and has no influence on a signal loop), when external equipment leaks electricity, the external ground 2 of HDMI wire or AV wire passes through the protection isolation wire 5 and then reaches the main board ground 3, and when the leakage current is large, the external ground 2 of HDMI wire, AV wire and the protection isolation wire 5 heat, but because the protection isolation wire 5 is thinner, the protection isolation wire 5 is fused, the external ground 2 of HDMI wire and AV wire is disconnected from the main board ground 3 of the set top box, and the current can not form a loop, so that continuous leakage is prevented, and the set top box and the television are protected from being burnt.

In this embodiment, the protective isolation wire 5 has a size of about 0.15mm, and both ends thereof are thick (0.5 mm). The protective isolation line 5 is designed in such a way that: when large current passes through, the heat dissipation is slower after the middle part generates heat, and the middle part can be fused more quickly, so that the purpose of quick protection is achieved.

The foregoing examples merely illustrate specific embodiments of the utility model, which are described in greater detail and are not to be construed as limiting the scope of the utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model.

Claims

1. The set top box interface protection device comprises a set top box main board and an external interface arranged on the set top box main board, wherein the external layer ground of the external interface is connected with the main board ground of the set top box main board.

2. The set-top box interface guard of claim 1, wherein the width of the connection between the two ends of the protection isolation line and the outer ground and the main board ground is greater than the width of the middle of the protection isolation line.

3. The set-top box interface guard of claim 2, wherein the width of the two ends of the protection isolation line is 0.4mm-0.6mm, and the width of the middle of the protection isolation line is 0.14mm-0.16mm.

4. A set top box interface guard according to any one of claims 1 to 3 wherein the external interface is one or more of an HDMI interface, an AV interface and an RF interface.