CN203368021U - Protection circuit for set top box - Google Patents
Protection circuit for set top box Download PDFInfo
- Publication number
- CN203368021U CN203368021U CN 201320507151 CN201320507151U CN203368021U CN 203368021 U CN203368021 U CN 203368021U CN 201320507151 CN201320507151 CN 201320507151 CN 201320507151 U CN201320507151 U CN 201320507151U CN 203368021 U CN203368021 U CN 203368021U
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- CN
- China
- Prior art keywords
- top box
- set top
- capacitor
- switching circuit
- linked switch
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
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Abstract
The utility model discloses a protection circuit for a set top box. The protection circuit is connected between a total power input end of the set top box and a power supply module of the set top box. The protection circuit comprises a linked switch SW, wherein two static contacts 2, 3 at the same side of the linked switch SW are connected with the mains supply and the total power input end of the set top box respectively, the total power input end of the set top box is sequentially connected with a resistor R1 and a capacitor C1 in series, the other end of the capacitor C1 is grounded, and two static contacts 1, 4 at the other side of the linked switch SW are connected with two ends of the capacitor C1 respectively; and a node of the capacitor C1 and the resistor R1 is sequentially connected with a triode switching circuit and an MOS (metal oxide semiconductor) transistor switching circuit, and the output end of the MOS resistor switching circuit is connected with the power supply module of the set top box. The protection circuit disclosed by the utility model protects hardware equipment of the set top box from being damaged by frequent switching, and improves the safety of the set top box.
Description
Technical field
The utility model relates to Set Top Box, particularly a kind of protective circuit for Set Top Box.
Background technology
Set Top Box is in the situation that frequent switching on and shutting down; the instant high-voltage produced can damage top-set hardware equipment; add a protective circuit in Set Top Box; just can guarantee can be frequently to top-set hardware equipment power on/off; thereby the protection Set Top Box, so the protection Set Top Box seems very important when the subscriber switch machine.
The utility model content
For realizing above-mentioned imagination, the utility model provides a kind of protective circuit for Set Top Box.
Technical solution adopted in the utility model is:
A kind of protective circuit for Set Top Box, described protective circuit is connected between the total input of Set Top Box power supply and Set Top Box supply module, described protective circuit comprises a linked switch SW, two of the same sides of described linked switch SW fixed contact 2,3 connects respectively civil power and the total input of Set Top Box power supply, the total input of Set Top Box power supply is series resistance R1 and capacitor C 1 successively, capacitor C 1 other end ground connection, two fixed contacts of the opposite side of described linked switch SW 1,4 connect respectively the two ends of capacitor C 1; The node of described capacitor C 1 and resistance R 1 is connecting triode switching circuit and metal-oxide-semiconductor switching circuit successively, the output junctor top box supply module of described metal-oxide-semiconductor switching circuit.
Described transistor switching circuit comprises NPN triode Q2, and the base stage of described triode Q2 connects capacitor C 1 by resistance R 3, grounded emitter, and collector electrode is be connected with R2+5V of contact resistance R4 voltage successively; Described metal-oxide-semiconductor switching circuit comprises PMOS field effect transistor Q1, the grid contact resistance R4 of field effect transistor Q1, source electrode connection+5V voltage, drain electrode junctor top box supply module.
The utility model utilizes the special key pattern of linked switch SW, and make in when shutdown and can allow fast capacitor discharge, capacitor charging delayed trigger start during start, thus protection top-set hardware equipment exempts from the damage of frequent switching on and shutting down, the fail safe that improves Set Top Box.
The accompanying drawing explanation
Fig. 1 is the embodiment schematic diagram of protective circuit described in the utility model.
Embodiment
Understand technology contents of the present utility model for convenience of those skilled in the art, below in conjunction with drawings and Examples, the utility model is described in further detail.
As shown in Figure 1, the protective circuit for Set Top Box that the utility model discloses, be connected between the total input of Set Top Box power supply and Set Top Box supply module, can realize the purpose of protection top-set hardware equipment when frequent switching on and shutting down.Concrete, protective circuit comprises a linked switch SW, two of the same sides of described linked switch SW fixed contact 2,3 connects respectively civil power and the total input of Set Top Box power supply, the total input of Set Top Box power supply is series resistance R1 and capacitor C 1 successively, capacitor C 1 other end ground connection, two fixed contacts of the opposite side of described linked switch SW 1,4 connect respectively the two ends of capacitor C 1; The node of described capacitor C 1 and resistance R 1 is connecting triode switching circuit and metal-oxide-semiconductor switching circuit successively, the output junctor top box supply module of described metal-oxide-semiconductor switching circuit.Described transistor switching circuit comprises NPN triode Q2, and the base stage of described triode Q2 connects capacitor C 1 by resistance R 3, grounded emitter, and collector electrode is be connected with R2+5V of contact resistance R4 voltage successively; Described metal-oxide-semiconductor switching circuit comprises PMOS field effect transistor Q1, the grid contact resistance R4 of field effect transistor Q1, source electrode connection+5V voltage, drain electrode junctor top box supply module.
Linked switch SW is the master switch of Set Top Box voltage, when the user starts shooting, and fixed contact 2 and 3 short circuits, fixed contact 1 and 4 disconnects, and power supply starts power supply; When the user shuts down, fixed contact 2 and 3 disconnects, and power supply disconnects, fixed contact 1 and 4 short circuits, 1 liang of terminal shortcircuit of capacitor C, capacitor C 1 repid discharge.
When the user opens the Set Top Box mains switch, capacitor C 1 starts charging, when the voltage of C1 surpasses certain specific threshold voltage, NPN triode Q2 conducting, the control end grid voltage of PMOS field effect transistor Q1 is reduced, thereby control field effect transistor Q1 conducting, the supply module input high level, power to the master chip (CPU, flash, DDR etc.) of Set Top Box and tuner hardware device.During set-top-box opening, capacitor C 1 has a process of charging, has in fact postponed the power supply of set-top box device.When the user closes the Set Top Box mains switch, Set Top Box outage, capacitor C 1 repid discharge.
When the frequent switching on and shutting down of Set Top Box switch, the capacitor C of starting shooting for the first time 1 charging, when the voltage of capacitor C 1 reaches threshold voltage, triode Q1 does not have conducting, at this moment shutdown fast again, capacitor C 1 repid discharge.Next time is while again starting shooting because express delivery of capacitor C 1 has been discharged, so for the second time start process with the same for the first time.In the process of quick repeated switching, top-set hardware equipment does not all have power transmission, thereby has protected Set Top Box.
Above-described embodiment is only wherein specific implementation of the present utility model, and it describes comparatively concrete and detailed, but can not therefore be interpreted as the restriction to the utility model the scope of the claims.It should be pointed out that for the person of ordinary skill of the art, without departing from the concept of the premise utility, can also make some distortion and improvement, these apparent replacement forms all belong to protection range of the present utility model.
Claims (2)
1. the protective circuit for Set Top Box, described protective circuit is connected between the total input of Set Top Box power supply and Set Top Box supply module, it is characterized in that, described protective circuit comprises a linked switch SW, two of the same sides of described linked switch SW fixed contact 2,3 connects respectively civil power and the total input of Set Top Box power supply, the total input of Set Top Box power supply is series resistance R1 and capacitor C 1 successively, capacitor C 1 other end ground connection, two fixed contacts of the opposite side of described linked switch SW 1,4 connect respectively the two ends of capacitor C 1; The node of described capacitor C 1 and resistance R 1 is connecting triode switching circuit and metal-oxide-semiconductor switching circuit successively, the output junctor top box supply module of described metal-oxide-semiconductor switching circuit.
2. protective circuit according to claim 1, it is characterized in that, described transistor switching circuit comprises NPN triode Q2, and the base stage of described triode Q2 connects capacitor C 1 by resistance R 3, grounded emitter, collector electrode is be connected with R2+5V of contact resistance R4 voltage successively; Described metal-oxide-semiconductor switching circuit comprises PMOS field effect transistor Q1, the grid contact resistance R4 of field effect transistor Q1, source electrode connection+5V voltage, drain electrode junctor top box supply module.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201320507151 CN203368021U (en) | 2013-08-20 | 2013-08-20 | Protection circuit for set top box |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201320507151 CN203368021U (en) | 2013-08-20 | 2013-08-20 | Protection circuit for set top box |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203368021U true CN203368021U (en) | 2013-12-25 |
Family
ID=49815740
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201320507151 Expired - Fee Related CN203368021U (en) | 2013-08-20 | 2013-08-20 | Protection circuit for set top box |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203368021U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103701089A (en) * | 2013-12-31 | 2014-04-02 | 昌辉汽车转向系统（黄山）有限公司 | Hardware overload or short circuit protection circuit and DC (Direct Current) power supply circuit |
| CN107508272A (en) * | 2017-08-29 | 2017-12-22 | 王莹 | A kind of Vehicular power protective circuit of super low-power consumption |
| CN117134292A (en) * | 2023-10-26 | 2023-11-28 | 深圳清大电子科技有限公司 | Safety protection circuit of display screen |
-
2013
- 2013-08-20 CN CN 201320507151 patent/CN203368021U/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103701089A (en) * | 2013-12-31 | 2014-04-02 | 昌辉汽车转向系统（黄山）有限公司 | Hardware overload or short circuit protection circuit and DC (Direct Current) power supply circuit |
| CN107508272A (en) * | 2017-08-29 | 2017-12-22 | 王莹 | A kind of Vehicular power protective circuit of super low-power consumption |
| CN117134292A (en) * | 2023-10-26 | 2023-11-28 | 深圳清大电子科技有限公司 | Safety protection circuit of display screen |
| CN117134292B (en) * | 2023-10-26 | 2024-01-23 | 深圳清大电子科技有限公司 | Safety protection circuit of display screen |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20131225 Termination date: 20140820 |
|
| EXPY | Termination of patent right or utility model |