KR20060001135A - Adapter with improved surge protection function - Google Patents

Abstract

It is an object of the present invention to provide an adapter with an improved surge protection function for quickly bypassing a surge high voltage to ground.

The adapter of the present invention includes a first coil L1 formed at the live end LT of the AC input voltage Vin, a second coil L2 formed at the neutral end NT of the AC input voltage Vin, A plurality of capacitors C1-C4 connected between the live terminal LT and the neutral terminal NT, and a surge absorber connected in parallel to at least one of the first coil L1 or the second coil L2. A line filter unit 21 including SA1; A bridge rectifier 22 for rectifying the voltage through the line filter 21; A transformer unit 23 for converting the voltage from the bridge rectifier unit 22 under reduced pressure; A DC output unit 24 for converting the voltage from the transformer unit 23 into various DC voltages; A feedback circuit section 25 for detecting and feeding back a voltage from the transformer section 23; A PWM circuit section 26 including a MOS FET (M) for switching the PWM voltage according to the magnitude of the feedback voltage from the feedback circuit section 25 to control the magnitude of the input voltage of the transformer section 23; And a surge buffer capacitor SC connected in parallel between the drain and the source of the MOS FET M to bypass the surge high voltage to ground.

IP Boards, Adapters, Surge Protection, Surge Absorbers

Description

Adapter with improved surge protection {ADAPTER WITH IMPROVED SURGE PROTECTION FUNCTION}

1 is a circuit diagram of a conventional adapter.

2 is a circuit diagram of an adapter according to the invention.

Explanation of symbols on main parts of drawing

21 line filter 22 bridge rectifier

23: transformer section 24: DC output section

25: feedback circuit section 26: PWM circuit section

27: protection circuit part Vin: AC input voltage

LT: Live Stage NT: Neutral Stage

L1: first coil L2: second coil

C1-C4: Capacitor SA0: Surge Absorber

SA1: Surge Absorber M: MOS FET

SC: Surge buffer capacitor

The present invention relates to an adapter applied to an IP board (LIPS), and in particular, by quickly bypassing the surge high voltage to ground, by quickly bypassing the surge high voltage caused by surge such as lightning to the ground circuit And an adapter with improved surge protection for protecting parts.

In general, in the case of a conventional LCD TV or monitor, an inverter and an adapter are separately made and used separately, but recently, an inverter / adapter integrated IP board (IP- BOARD (or LIPS) is becoming more common.

Here, in the case of LCD TVs, protection measures against surges are very important factors, and must satisfy both consumer safety and customer requirements at the same time.

One of the adapters applied to the conventional IP board will be described with reference to FIG. 1.

1 is a circuit diagram of a conventional adapter.

Referring to FIG. 1, a conventional adapter rectifies a voltage through a line filter unit 11 for suppressing high frequency noise included in an AC input voltage Vin, such as 110V or 220V, and the line filter unit 11. The bridge rectifier 12, the transformer 13 for depressurizing and converting the voltage from the bridge rectifier 12, and the voltage from the transformer 13 are various DC voltages, for example, 5V or 13V. A DC output unit 14 for outputting a DC voltage, a feedback circuit unit 15 for detecting and feeding back a voltage from the transformer unit 13, and the transformer according to the magnitude of the feedback voltage from the feedback circuit unit 15. PWM circuit portion 16 for controlling the magnitude of the input voltage of the unit 13 by the PWM method, and a protection circuit portion for protecting the PWM circuit portion 16 by maintaining the voltage on the line connected to the PWM circuit portion 16 at a constant voltage ( 17).

Meanwhile, a surge high voltage may be input through an input terminal by a surge such as a lightning strike. As a countermeasure against such a surge high voltage, a live terminal and a neutral terminal connected to both ends of the input voltage, that is, a fuse are connected to each other. Between the stages, surge absorbers are connected to bypass the high-voltage surge of about 500V.

Further, in the conventional adapter, a crocodile-shaped discharge pattern portion 18 is added between the neutral terminal and the ground terminal to discharge the surge high voltage to the ground, or surge discharge by adding a discharge pattern to the line filter part. Or perform a surge pass.

However, in such a conventional adapter, since there is no discharge path in the front and rear ends of the line filter part, the surge high voltage cannot be quickly bypassed to ground, which may cause damage to internal circuits and components, and in particular, the PWM circuit part 16 ) Can damage or destroy the switching MOS FET included in this case, in which case there is a problem that the PWM circuit unit does not operate.

The present invention has been proposed to solve the above problems, the object of which is to quickly bypass the surge high voltage to ground, to quickly bypass the surge high voltage caused by surge such as lightning to the ground circuit And to provide an adapter with improved surge protection to protect parts.

In order to achieve the above object of the present invention, the adapter which improves the surge protection function of the present invention,

At least one of a first coil formed at the live end of the AC input voltage, a second coil formed at the neutral end of the AC input voltage, a plurality of capacitors connected between the live end and the neutral end, and the first coil or the second coil A line filter unit including a surge absorber connected in parallel to the control unit;

A bridge rectifier for rectifying the voltage through the line filter;

A transformer for decompressing the voltage from the bridge rectifier;

A DC output unit converting the voltage from the transformer unit into various DC voltages and outputting the converted DC voltages;

A feedback circuit unit for detecting and feeding back a voltage from the transformer unit;

A PWM circuit part including a MOS FET which is switched in a PWM manner according to the magnitude of the feedback voltage from the feedback circuit part and controls the input voltage of the transformer part; And

Surge buffer capacitor connected in parallel between the drain and the source of the MOS FET to bypass the surge high voltage to ground

Characterized in having a.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a circuit diagram of an adapter according to the invention.

Referring to FIG. 2, the adapter according to the present invention includes a line filter unit 21, a bridge rectifier unit 22, a transformer unit 23, a DC output unit 24, a feedback circuit unit 25, a PWM circuit unit 26, and the like. And a surge buffer capacitor (SC).

The line filter 21 may include a first coil L1 formed at the live end LT of the AC input voltage Vin, and a second coil L2 formed at the neutral end NT of the AC input voltage Vin. And a plurality of capacitors C1-C4 connected between the live terminal LT and the neutral terminal NT, and a surge app connected in parallel to at least one of the first coil L1 or the second coil L2. It includes a gerber (SA1).

The surge absorber SA1 provides a path for quickly bypassing the surge high voltage between the front and rear ends of the first coil L1 and / or the second coil L2 to ground.

The bridge rectifying unit 22 is composed of four bridge diodes to full-wave rectify the voltage through the line filter unit 21. The transformer 23 converts the voltage from the bridge rectifier 22 into a low voltage. The DC output unit 24 converts the voltage from the transformer unit 23 into various DC voltages such as approximately 5V or 13V and outputs the same. The feedback circuit unit 25 detects and feeds back a voltage from the transformer unit 23.

The PWM circuit unit 26 includes a MOS FET (M) that is switched in a PWM manner according to the magnitude of the feedback voltage from the feedback circuit unit 25 to control the magnitude of the input voltage of the transformer unit 23. The drain of the MOS FET is connected to the transformer section 23, its source is connected to ground, and its gate is connected to an internal PWM switching signal.

The surge buffer capacitor SC is connected in parallel between the drain and the source of the MOS FET M to quickly bypass the surge high voltage to ground.

In addition, the adapter maintains the voltage on the line connected to the PWM circuit unit 26 at a constant voltage to protect the PWM circuit unit 26, the live terminal (LT) and the neutral of both ends of the input voltage It is connected between the stage (NT), it may include a surge absorber (SA0) for bypassing the surge high voltage between the both ends.

In addition, in the adapter of the present invention, a crocodile-shaped discharge pattern portion 28 is added between the neutral end and the magazine end to discharge the surge high voltage to ground.

Hereinafter, the operation and effects of the present invention will be described in detail with reference to the accompanying drawings.

Referring to FIG. 2, an AC input voltage Vin input to an adapter of the present invention is provided to the bridge rectifier 22 through a line filter unit 21. The filter circuit including the second coils L1 and L2 and the plurality of capacitors C1 to C4 removes high frequency noise such as a high frequency signal and switching noise included in the AC input voltage Vin.

In addition, the surge absorber SA0 of the present invention bypasses the surge high voltage between the live terminal LT and the neutral terminal NT, which are both ends of the input voltage. In addition, the discharge pattern part 28 included in the adapter of the present invention allows the surge high voltage at the neutral terminal to surge discharge or surge pass to the ground terminal.

In addition, the surge absorber SA1 of the present invention provides a path for quickly bypassing the surge high voltage between the front and rear ends of the first coil L1 and / or the second coil L2 to ground, which is When it is normally open, if a preset voltage, for example, a high voltage such as 4KV or 6KV is generated, it is shorted by an arc discharge by itself, and the surge voltage of the rear stage is transferred to the front end. It quickly passes the high, or front-end surge high voltage to the rear end for quick bypass to ground.

Without such a surge absorber SA1, energy is accumulated in the filter, so a rapid bypass is not achieved, and an internal circuit or a component may be damaged by the surge high voltage. However, as described above, the surge absorber SA1 of the present invention provides a path for quickly bypassing the surge high voltage to ground, so that the surge high voltage can be quickly bypassed to ground.

Next, when the bridge rectifier 22 full-wave rectifies the voltage through the line filter unit 21 and outputs the voltage to the transformer unit 23, the transformer unit 23 receives the voltage from the bridge rectifier 22. The DC output unit 24 is output by converting the voltage into a low voltage, and the DC output unit 24 converts the voltage from the transformer unit 23 into various DC voltages such as approximately 5V or 13V and outputs the same.

Then, when the feedback circuit section 25 of the present invention detects the voltage from the transformer section 23 and feeds it back to the PWM circuit section 26, the PWM circuit section 26 returns the feedback voltage from the feedback circuit section 25. The MOS FET (M) is switched in a PWM manner according to the size of, to control the magnitude of the input voltage of the transformer 23 connected to the MOS FET (M). Accordingly, the DC voltage output from the DC output unit 24 can be adjusted to a voltage having a desired magnitude.

At this time, when the MOS FET (M) is connected to the transformer unit 23, the surge high voltage flows through the transformer unit 23, the MOS FET (M) is damaged or destroyed, or IC The PWM circuit portion itself is destroyed so that the switching operation cannot be performed. However, in the adapter of the present invention, the surge buffer capacitor SC connected between the drain and the source of the MOS FET M is the drain of the MOS FET M. By quickly bypassing the surge high voltage flowing into the ground, the MOS FET M is not damaged by the surge high voltage.

In addition, the PWM circuit unit 26 of the adapter is connected to the transformer unit 23 and the feedback circuit unit 25 to input and output voltage, respectively, wherein the protection circuit unit 27 of the present invention is the input voltage The PWM circuit unit 26 is protected by maintaining a constant voltage so as not to be greater than the constant voltage.

As described above, the present invention primarily adds a surge absorber to the line filter so that the surge high voltage can be quickly bypassed to ground, and secondly, the drain source of the MOS FET included in the PWM circuit portion. Through a capacitor that connects, the MOS FET is prevented from being damaged by a surge high voltage.

According to the present invention as described above, in the adapter applied to the IP board (LIPS), it is possible to quickly bypass the surge high voltage to ground, thereby quickly bypass the surge high voltage caused by surge such as lightning strike to ground This protects the internal circuits and components.

Claims (3)

The first coil L1 formed at the live end LT of the AC input voltage Vin, the second coil L2 formed at the neutral end NT of the AC input voltage Vin, and the live end LT. And a line including a plurality of capacitors C1-C4 connected between the neutral terminal NT and a surge absorber SA1 connected in parallel to at least one of the first coil L1 or the second coil L2. A filter unit 21; A bridge rectifier 22 for rectifying the voltage through the line filter 21; A transformer unit 23 for converting the voltage from the bridge rectifier unit 22 under reduced pressure; A DC output unit 24 for converting and outputting a voltage from the transformer unit 23 into various DC voltages; A feedback circuit section 25 for detecting and feeding back a voltage from the transformer section 23; A PWM circuit section 26 including a MOS FET (M) for switching the PWM voltage according to the magnitude of the feedback voltage from the feedback circuit section 25 to control the magnitude of the input voltage of the transformer section 23; And Surge buffer capacitor (SC) connected in parallel between the drain and the source of the MOS FET (M) to bypass the surge high voltage to ground Adapter with improved surge protection, characterized in that provided with. The method of claim 1, wherein the adapter Adapter for improving the surge protection, characterized in that it further comprises a protection circuit portion (27) to protect the PWM circuit portion (26) by maintaining a voltage on the line connected to the PWM circuit portion (26). The method of claim 1, wherein the adapter The surge protection function is connected between the live terminal LT and the neutral terminal NT, which are both ends of the input voltage, and further includes a surge absorber SA0 for bypassing the high-voltage surge between the both ends. Improved adapter.

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