TWI641854B

TWI641854B - Fault warning circuit

Info

Publication number: TWI641854B
Application number: TW106120982A
Authority: TW
Inventors: 詹子增; 呂基男
Original assignee: 宏碁股份有限公司
Priority date: 2017-06-23
Filing date: 2017-06-23
Publication date: 2018-11-21
Also published as: TW201905477A

Abstract

故障警示電路，包含有一偵測單元，耦接至一接地接腳，用來偵測一感測電壓訊號，其中該感測電壓訊號係有關於流入該接地接腳之一電流；一補償模組，耦接於該偵測單元，用來根據該感測電壓訊號產生一補償電壓訊號；一控制單元，耦接於該補償模組，用來根據該補償電壓訊號產生一控制訊號；以及一警示單元，用來根據該控制訊號執行一警示功能。The fault warning circuit includes a detecting unit coupled to a grounding pin for detecting a sensing voltage signal, wherein the sensing voltage signal is related to a current flowing into the grounding pin; a compensation module The detection unit is coupled to the detection unit for generating a compensation voltage signal according to the sensing voltage signal; a control unit coupled to the compensation module for generating a control signal according to the compensation voltage signal; and a warning The unit is configured to perform a warning function according to the control signal.

Description

故障警示電路Fault warning circuit

本發明係指一種故障警示電路，尤指一種可感測接地接腳的連接異常以執行警示功能並提示使用者免於觸電之危險的故障警示電路。The invention relates to a fault warning circuit, in particular to a fault warning circuit capable of sensing the abnormal connection of the grounding pin to perform the warning function and prompting the user to avoid the danger of electric shock.

目前市面上的電子產品，如智慧型手機、可攜式電子裝置或是筆記型電腦等的機殼材質多為塑膠材質，但隨著時代演進，使用者在考量使用質感或是美觀等因素之下，越來越多使用者趨向選擇使用金屬材質機殼之電子裝置。然而在外觀華麗的條件之下，由於金屬機殼之導電特性，若是具有金屬機殼的電子裝置在進行充電時又遭遇到接地功能失效的話將會產生漏電流的情況而使機殼上有殘存靜電，如此一來，金屬機殼在美觀的包裝下反而讓使用者暴露在觸電的風險之下。At present, the electronic components on the market, such as smart phones, portable electronic devices or notebook computers, are mostly made of plastic materials, but as the times evolve, users consider the use of texture or aesthetic factors. Under the circumstance, more and more users tend to choose electronic devices using metal casings. However, under the conditions of gorgeous appearance, due to the conductive characteristics of the metal casing, if the electronic device with the metal casing encounters the failure of the grounding function when charging, the leakage current will occur and the casing will remain. Static electricity, as a result, the metal casing is exposed to the risk of electric shock under aesthetic packaging.

一般來說，在充電時通常係藉由三接腳的充電器連接至大地以排除靜電。請參考第1圖，第1圖為傳統之充電器10之接地功能的示意圖。充電器10包含有一次側接地端PG、二次側接地端SG以及機殼接地（frame ground）端FG。一次側接地端PG經由電容CY1耦接至二次側接地端SG與機殼接地端FG，並經由機殼接地端FG連接至大地。值得注意的是，若機殼接地端FG發生故障而沒有正確連接時，將會造成使用者觸電之風險。因此，如何感測機殼接地端FG是否異常，以執行警示功能並提示使用者免於觸電之危險，也就成為業界所努力的目標之一。Generally, when charging, it is usually connected to the ground by a three-pin charger to remove static electricity. Please refer to FIG. 1 , which is a schematic diagram of the grounding function of the conventional charger 10 . The charger 10 includes a primary side ground end PG, a secondary side ground end SG, and a frame ground end FG. The primary ground terminal PG is coupled to the secondary ground terminal SG and the chassis ground terminal FG via the capacitor CY1, and is connected to the ground via the chassis ground terminal FG. It is worth noting that if the chassis ground FG fails and is not properly connected, it will cause the user to risk electric shock. Therefore, how to sense whether the FG of the chassis grounding terminal is abnormal to perform the warning function and prompt the user to avoid the risk of electric shock has become one of the goals of the industry.

因此，本發明之主要目的之一即在於提供一種可感測接地接腳的連接異常以執行警示功能並提示使用者免於觸電之危險的故障警示電路，以解決上述問題。Accordingly, one of the primary objects of the present invention is to provide a fault warning circuit that senses a connection abnormality of a grounding pin to perform an alert function and prompts the user to avoid the risk of electric shock to solve the above problem.

本發明提供一種故障警示電路，包含有：一偵測單元，耦接至一接地接腳，用來偵測一感測電壓訊號，其中該感測電壓訊號係有關於流入該接地接腳之一電流；一補償模組，耦接於該偵測單元，用來根據該感測電壓訊號產生一補償電壓訊號；一控制單元，耦接於該補償模組，用來根據該補償電壓訊號產生一控制訊號；以及一警示單元，用來根據該控制訊號執行一警示功能。The present invention provides a fault warning circuit, comprising: a detecting unit coupled to a grounding pin for detecting a sensing voltage signal, wherein the sensing voltage signal is related to flowing into the grounding pin A compensation module is coupled to the detection unit for generating a compensation voltage signal according to the sensing voltage signal; a control unit coupled to the compensation module for generating a signal according to the compensation voltage signal a control signal; and a warning unit for performing an alert function according to the control signal.

本發明另提供一種故障警示方法，用於一故障警示電路，包含有：取得一感測電壓訊號；根據該感測電壓訊號進行一補償程序，以產生一補償電壓訊號；將該補償電壓訊號與一臨界電壓值進行比較，以產生一控制訊號；以及根據該控制訊號以執行一警示功能。The present invention further provides a fault warning method for a fault warning circuit, comprising: obtaining a sensing voltage signal; performing a compensation procedure according to the sensing voltage signal to generate a compensation voltage signal; and the compensation voltage signal A threshold voltage value is compared to generate a control signal; and an alert function is performed based on the control signal.

請參考第2圖，第2圖為本發明實施例之一故障警示電路20之示意圖。故障警示電路20可應用於各式變壓器（Adapter）與充電器，例如包含有三接腳的充電器上，值得注意的是，在正常狀態下，電流可被導向流至機殼接地（Frame Ground）端FG而正常運作，而當接地功能故障發生時，所應用之充電器上的其他電路與機殼接地端FG之間形成斷路造成接地路徑異常，因而造成使用者觸電之危險。本發明即針對充電器之機殼接地端的故障情況進行偵測，並且在故障時執行警示功能，使得使用者可根據警示功能輕易地判斷充電器是否正常運作或故障，進而避免觸電的危險。詳細來說，故障警示電路20包含有一偵測單元200、一補償模組202、一控制單元204以及一警示單元206。偵測單元200耦接於一接地接腳，其中該接地接腳可為一機殼接地接腳，但不以此為限。例如，如第2圖所示，偵測單元200耦接至機殼接地端FG。偵測單元200用來偵測一感測電壓訊號Vsense，其中感測電壓訊號Vsense係有關於流入機殼接地端FG之電流。感測電壓訊號Vsense係基於充電器內部電路流入機殼接地端FG的電流所產生。舉例來說，偵測單元200可耦接於一充電器之一次側接地端與機殼接地端FG之間，在此情況下，感測電壓訊號Vsense為由充電器之一次側接地端流入機殼接地端FG的電流所產生。Please refer to FIG. 2, which is a schematic diagram of a fault warning circuit 20 according to an embodiment of the present invention. The fault warning circuit 20 can be applied to various types of transformers and chargers, for example, a charger including a three-pin. It is worth noting that under normal conditions, current can be directed to the chassis ground (Frame Ground). The FG operates normally, and when the grounding function fails, an open circuit is formed between the other circuit on the applied charger and the chassis ground FG, causing the grounding path to be abnormal, thereby causing the user to be in danger of electric shock. The invention detects the fault condition of the grounding end of the casing of the charger, and performs the warning function when the fault occurs, so that the user can easily judge whether the charger is normally operated or malfunction according to the warning function, thereby avoiding the danger of electric shock. In detail, the fault warning circuit 20 includes a detecting unit 200, a compensation module 202, a control unit 204, and a warning unit 206. The detecting unit 200 is coupled to a grounding pin, wherein the grounding pin can be a chassis grounding pin, but is not limited thereto. For example, as shown in FIG. 2, the detecting unit 200 is coupled to the chassis ground terminal FG. The detecting unit 200 is configured to detect a sensing voltage signal Vsense, wherein the sensing voltage signal Vsense has a current flowing into the chassis ground FG. The sense voltage signal Vsense is generated based on the current flowing into the chassis ground terminal FG of the internal circuit of the charger. For example, the detecting unit 200 can be coupled between the primary grounding end of the charger and the chassis grounding end FG. In this case, the sensing voltage signal Vsense is flown by the primary side grounding end of the charger. The current of the shell ground terminal FG is generated.

進一步地，補償模組202耦接於偵測單元200，用來接收感測電壓訊號Vsense並根據感測電壓訊號Vsense產生一補償電壓訊號Vcomp。例如，補償模組202可對感測電壓訊號Vsense進行訊號放大及/或補償操作以產生補償電壓訊號Vcomp。控制單元204耦接於補償模組202，用來根據補償電壓訊號Vcomp以判斷機殼接地端FG的接地功能是否為斷路異常，以產生控制訊號Vcont。警示單元206則耦接於控制單元204，用來根據控制訊號Vcont以判斷是否執行警示功能。Further, the compensation module 202 is coupled to the detecting unit 200 for receiving the sensing voltage signal Vsense and generating a compensation voltage signal Vcomp according to the sensing voltage signal Vsense. For example, the compensation module 202 can perform signal amplification and/or compensation operations on the sensing voltage signal Vsense to generate a compensation voltage signal Vcomp. The control unit 204 is coupled to the compensation module 202 for determining whether the grounding function of the chassis ground terminal FG is an open circuit abnormality according to the compensation voltage signal Vcomp to generate the control signal Vcont. The warning unit 206 is coupled to the control unit 204 for determining whether to perform the alert function according to the control signal Vcont.

關於故障警示電路20之運作可歸納為一流程30，請參考第3圖，流程30包含以下步驟：The operation of the fault warning circuit 20 can be summarized as a process 30, please refer to FIG. 3, and the process 30 includes the following steps:

步驟300：開始。Step 300: Start.

步驟302：偵測感測電壓訊號。Step 302: Detect the sensing voltage signal.

步驟304：對感測電壓訊號進行訊號補償程序以產生補償電壓訊號。Step 304: Perform a signal compensation procedure on the sensing voltage signal to generate a compensation voltage signal.

步驟306：判斷補償電壓訊號是否大於一臨限值。Step 306: Determine whether the compensation voltage signal is greater than a threshold.

步驟308：執行警示功能。Step 308: Perform a warning function.

步驟310：結束。Step 310: End.

根據流程30，於步驟302中，偵測單元200可依據流入機殼接地端FG的電流來偵測一感測電壓訊號Vsense。舉例來說，請參考第4圖，第4圖為本發明實施例之一故障警示電路40之示意圖。值得注意的是，第2圖之故障警示電路20與第4圖之故障警示電路40中具有相同名稱之元件具有類似的運作方式與功能，在此不再贅述。如第4圖所示，偵測單元200包含一電阻R1，其一端耦接於機殼接地端FG，且另一端可耦接於所應用之變壓器或充電器的內部電路。例如，電阻R1之一端耦接於機殼接地端FG，且電阻R1之另一端耦接於充電器之一次側接地端。例如，當充電器之一次側接地端係經由一橋接電容耦合至二次側，電阻R1之一端可耦接於前述橋接電容且電阻R1之另一端可耦接至機殼接地端FG。例如，電阻R1之一端耦接於機殼接地端FG，且電阻R1之另一端耦接於充電器之一儲能元件之一低電位端。因此，原先要流入機殼接地端FG之電流將會先流過電阻R1再流入機殼接地端FG。如此一來，流入機殼接地端FG之電流可由偵測單元200感測，並將所感測的電流轉換為相對應的感測電壓訊號Vsense並傳遞至補償模組202。也就是說。電阻R1可將電流轉換為感測電壓訊號Vsense，感測電壓訊號Vsense即為電流流經感測電阻R1時所產生的跨壓。According to the process 30, in step 302, the detecting unit 200 can detect a sensing voltage signal Vsense according to the current flowing into the chassis ground FG. For example, please refer to FIG. 4, which is a schematic diagram of a fault warning circuit 40 according to an embodiment of the present invention. It should be noted that the fault warning circuit 20 of FIG. 2 and the fault alarm circuit 40 of FIG. 4 have similar operation modes and functions, and are not described herein again. As shown in FIG. 4, the detecting unit 200 includes a resistor R1, one end of which is coupled to the chassis ground terminal FG, and the other end of which is coupled to the internal circuit of the applied transformer or charger. For example, one end of the resistor R1 is coupled to the chassis ground terminal FG, and the other end of the resistor R1 is coupled to the primary side ground end of the charger. For example, when the primary ground terminal of the charger is coupled to the secondary side via a bridge capacitor, one end of the resistor R1 can be coupled to the bridge capacitor and the other end of the resistor R1 can be coupled to the chassis ground terminal FG. For example, one end of the resistor R1 is coupled to the chassis ground terminal FG, and the other end of the resistor R1 is coupled to one of the low potential terminals of one of the energy storage elements of the charger. Therefore, the current that originally flows into the ground terminal FG of the chassis will flow through the resistor R1 and then flow into the chassis ground FG. As a result, the current flowing into the grounding terminal FG of the chassis can be sensed by the detecting unit 200, and the sensed current is converted into a corresponding sensing voltage signal Vsense and transmitted to the compensation module 202. In other words. The resistor R1 converts the current into the sensing voltage signal Vsense, and the sensing voltage signal Vsense is the voltage generated when the current flows through the sensing resistor R1.

由於感測電壓訊號Vsense中可能會包含充電器內部電路之雜訊，因此於步驟304中，可藉由補償模組202對感測電壓訊號Vsense進行訊號補償處理，例如雜訊濾波、訊號放大及平移電壓位準等，來移除不理想效應並且濾除雜訊以產生補償電壓訊號Vcomp傳遞至控制單元204。Since the sensing voltage signal Vsense may include the noise of the internal circuit of the charger, in step 304, the compensation module 202 may perform signal compensation processing on the sensing voltage signal Vsense, such as noise filtering, signal amplification, and The voltage level is shifted to remove the undesirable effect and the noise is filtered to generate a compensation voltage signal Vcomp that is passed to the control unit 204.

於步驟306中，控制單元204將補償電壓訊號Vcomp與一臨限電壓Vth進行比較，以判斷機殼接地端FG之接地功能是否正常。舉例來說，當補償電壓訊號Vcomp大於臨限電壓Vth時，表示機殼接地端FG之接地功能為正常，確實可讓漏電流流入機殼接地端FG而達安全接地之目的。此時，由於機殼接地端FG之接地功能為正常，因而不需通知使用者，控制單元204產生相應控制訊號以指示警示單元206不執行警示功能。接著，繼續執行步驟302以持續感測機殼接地端FG之接地功能的連接是否異常。In step 306, the control unit 204 compares the compensation voltage signal Vcomp with a threshold voltage Vth to determine whether the grounding function of the chassis ground terminal FG is normal. For example, when the compensation voltage signal Vcomp is greater than the threshold voltage Vth, it indicates that the grounding function of the chassis ground terminal FG is normal, and the leakage current can flow into the chassis ground terminal FG for safety grounding. At this time, since the grounding function of the chassis grounding end FG is normal, the user is not required to notify the user, and the control unit 204 generates a corresponding control signal to instruct the warning unit 206 not to perform the warning function. Then, step 302 is continued to continuously sense whether the connection of the ground function of the chassis ground FG is abnormal.

另一方面，當補償電壓訊號Vcomp小於或等於臨限電壓Vth時，表示機殼接地端FG之接地功能發生故障而無法將漏電流導入機殼接地端FG，充電器內部電路與機殼接地端FG之間形成斷路。因此，當補償電壓訊號Vcomp小於或等於臨限電壓Vth時，控制單元204產生相應控制訊號以指示警示單元206執行警示功能，並執行步驟308。於步驟308中，警示單元206將根據控制單元204產生之控制訊號來執行警示功能來提示使用者。例如，當補償電壓訊號Vcomp小於或等於臨限電壓Vth時，控制單元204產生相應控制訊號以指示警示單元206執行警示功能，使得警示單元206據以執行一警示功能。例如，警示單元206可利用發光裝置顯示燈號，以警示使用者目前接地功能失效。如此一來，當使用者看見此燈號便可立即意會到可能因為接地功能失效而產生漏電的現象，進而採行緊急避護的動作。簡言之，透過本案的故障警示電路將可讓使用者輕易且立即地依照警示功能辨別機殼接地端FG之接地功能是否故障，以避免觸電事故發生。On the other hand, when the compensation voltage signal Vcomp is less than or equal to the threshold voltage Vth, it indicates that the grounding function of the chassis ground terminal FG is faulty and the leakage current cannot be introduced into the chassis ground terminal FG, and the charger internal circuit and the chassis ground terminal An open circuit is formed between the FGs. Therefore, when the compensation voltage signal Vcomp is less than or equal to the threshold voltage Vth, the control unit 204 generates a corresponding control signal to instruct the alert unit 206 to perform the alert function, and performs step 308. In step 308, the alert unit 206 will perform an alert function according to the control signal generated by the control unit 204 to prompt the user. For example, when the compensation voltage signal Vcomp is less than or equal to the threshold voltage Vth, the control unit 204 generates a corresponding control signal to instruct the alert unit 206 to perform an alert function, so that the alert unit 206 performs an alert function accordingly. For example, the alert unit 206 can display the light signal using the light emitting device to alert the user that the current grounding function has failed. In this way, when the user sees the light signal, the user can immediately realize the phenomenon that the grounding function may be lost due to the failure of the grounding function, and then the emergency avoidance action is adopted. In short, the fault warning circuit in this case will allow the user to easily and immediately follow the warning function to determine whether the grounding function of the chassis ground FG is faulty to avoid an electric shock accident.

進一步說明，請繼續參考第4圖，控制單元204包含一金氧半場效電晶體（Metal-Oxide-Semiconductor Field-Effect Transistor，MOSFET）M1以及一電阻R2。金氧半場效電晶體M1及電阻R2以串聯連接。警示電路206包含有發光二極體LED1、LED2（Light-Emitting Diode，LED）以及一電阻R3，發光二極體LED1、LED2及電阻R3以串聯連接至機殼接地端FG。金氧半場效電晶體M1包含有一閘極（Gate）耦接於補償模組202，用以接收補償電壓訊號Vcomp，一汲極（Drain）耦接於電阻R2，以及一源極（Source）耦接於機殼接地端FG。電阻R2之一端耦接於金氧半場效電晶體M1之汲極，而電阻R2另一端耦接於系統供應電源VDD，使金氧半場效電晶體M1形成一共源極放大器（Common Source Amplifier）結構。控制訊號Vcont由金氧半場效電晶體M1之汲極與電阻R2相耦接之節點產生並傳遞至警示電路206。警示單元206中之發光二極體LED1、LED2則以順向偏壓（Forward Bias）方式，串聯連接於金氧半場效電晶體M1的汲極與機殼接地端FG之間，即控制訊號Vcont耦接於發光二極體LED1之陽極，經發光二極體LED1的陰級與發光二極體LED2的陽極連接後，再由且發光二極體LED2的陰極耦接於電阻R3，並串聯至機殼接地端FG。Further, referring to FIG. 4, the control unit 204 includes a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) M1 and a resistor R2. The gold oxide half field effect transistor M1 and the resistor R2 are connected in series. The warning circuit 206 includes a light-emitting diode LED1, a light-emitting diode (LED), and a resistor R3. The light-emitting diode LED1, the LED2 and the resistor R3 are connected in series to the chassis ground terminal FG. The MOSFET has a gate coupled to the compensation module 202 for receiving the compensation voltage signal Vcomp, a drain coupled to the resistor R2, and a source coupling. Connect to the chassis ground terminal FG. One end of the resistor R2 is coupled to the drain of the MOS field M1, and the other end of the resistor R2 is coupled to the system supply power VDD, so that the MOS field M1 forms a Common Source Amplifier structure. . The control signal Vcont is generated by a node of the MOSFET and the resistor R2 coupled to the node of the MOSFET and is transmitted to the warning circuit 206. The LEDs LED1 and LED2 in the warning unit 206 are connected in series with the forward bias (Forward Bias) mode between the drain of the gold-oxygen half-effect transistor M1 and the ground terminal FG of the chassis, that is, the control signal Vcont. The anode of the LED 2 is coupled to the anode of the LED 2 through the cathode of the LED 2, and then the cathode of the LED 2 is coupled to the resistor R3 and connected in series to Chassis ground terminal FG.

詳細來說，金氧半場效電晶體M1其具有一臨限電壓Vth，當金氧半場效電晶體M1接收補償電壓訊號Vcomp時，會根據補償電壓訊號Vcomp以及臨限電壓Vth進行比較，當補償電壓訊號Vcomp大於臨限電壓Vth時金氧半場效電晶體M1將會導通，輸出的控制訊號Vcont為0V（或一低電位訊號）。由於控制訊號Vcont為0V或低電位訊號，警示單元406之發光二極體LED1、LED2無法被驅動發亮而不會執行警示功能運作；當補償電壓訊號Vcomp小於或等於臨限電壓Vth時將截斷（Cutoff）金氧半場效電晶體M1，輸出的控制訊號Vcont為系統供應電源VDD（或一高電位訊號）。警示單元406即依控制訊號Vcont而執行警示功能運作。此時，由於控制訊號Vcont為系統供應電源VDD或高電位訊號，發光二極體LED1、LED2將導通而發亮。In detail, the gold-oxygen half-field effect transistor M1 has a threshold voltage Vth. When the gold-oxygen half-field effect transistor M1 receives the compensation voltage signal Vcomp, it is compared according to the compensation voltage signal Vcomp and the threshold voltage Vth. When the voltage signal Vcomp is greater than the threshold voltage Vth, the gold-oxygen half-effect transistor M1 will be turned on, and the output control signal Vcont is 0V (or a low potential signal). Since the control signal Vcont is 0V or a low potential signal, the LEDs LED1 and LED2 of the warning unit 406 cannot be driven to be illuminated without performing the warning function; when the compensation voltage signal Vcomp is less than or equal to the threshold voltage Vth, the signal is cut off. (Cutoff) MOS half-effect transistor M1, the output control signal Vcont is the system supply power VDD (or a high potential signal). The alert unit 406 performs the alert function operation according to the control signal Vcont. At this time, since the control signal Vcont is the system supplying the power supply VDD or the high potential signal, the LEDs LED1 and LED2 will be turned on and lit.

換句話說，當機殼接地端FG之接地功能連接正常且偵測單元200感測到電流流過時，控制單元204不會啟動警示單元206，即警示單元406不執行警示功能；當機殼接地端FG之接地功能連接故障且偵測單元200感測到沒有電流流過時，控制單元204則啟動警示單元206，使警示單元406執行警示功能並發出亮光以警示使用者。因此，故障偵測電路40可有效地感測機殼接地端FG之接地功能的連接是否故障，並依此執行警示功能，而使用者可輕易且立即地依警示功能辨別是否有觸電之危險。In other words, when the grounding function of the chassis grounding terminal FG is normally connected and the detecting unit 200 senses that a current flows, the control unit 204 does not activate the warning unit 206, that is, the warning unit 406 does not perform the warning function; when the chassis is grounded When the ground function connection of the terminal FG is faulty and the detecting unit 200 senses that no current flows, the control unit 204 activates the warning unit 206 to cause the warning unit 406 to perform an alert function and emit a bright light to alert the user. Therefore, the fault detecting circuit 40 can effectively sense whether the connection of the grounding function of the grounding terminal FG of the casing is faulty, and perform the warning function accordingly, and the user can easily and immediately recognize the danger of electric shock according to the warning function.

此外，請參考第5圖，第5圖為本發明實施例一充電器50之示意圖。充電器50係應用第4圖之偵測單元200來進行偵測並啟動相應警示功能。在充電器50中，一次側接地端PG經由電容CY1耦接於二次側接地端SG以及機殼接地端FG。其中在充電器50進行充電時，漏電流I1會由一次側接地端PG經由電容CY1流向二次側接地端SG以及機殼接地端FG，為改善訊號品質，針對二次側接地端SG而設置有電容CC以及電阻RR，電阻RR以及電容CC以並聯方式耦接於電容CY1及二次側接地端SG之間。針對機殼接地端FG則設置有電容CF與電阻R1，電阻R1以及電容CF以並聯方式耦接於電容CY1以及機殼接地端FG之間。為了適當地導引漏電流I1經由電阻R1流向機殼接地端FG，避免漏電流I1經由電阻RR流至二次側接地端SG產生使用者觸電的危險，電阻R1之阻值較佳地可根據電阻RR之阻值來決定。由於漏電流I1係根據電阻值的反比而分流，因此電阻R1的電阻值設計為電阻RR的電阻值之0.5%至0.05%之間，以有效地導引大部分的漏電流I1經由電阻R1流至機殼接地端FG，並避免使用者觸電的危險。In addition, please refer to FIG. 5, which is a schematic diagram of a charger 50 according to an embodiment of the present invention. The charger 50 applies the detecting unit 200 of FIG. 4 to detect and activate the corresponding alert function. In the charger 50, the primary side ground terminal PG is coupled to the secondary side ground terminal SG and the chassis ground terminal FG via the capacitor CY1. When the charger 50 is being charged, the leakage current I1 flows from the primary ground terminal PG to the secondary ground terminal SG and the chassis ground terminal FG via the capacitor CY1 to improve the signal quality and is set for the secondary ground terminal SG. The capacitor CC and the resistor RR, the resistor RR and the capacitor CC are coupled in parallel between the capacitor CY1 and the secondary ground terminal SG. The capacitor grounding terminal FG is provided with a capacitor CF and a resistor R1. The resistor R1 and the capacitor CF are coupled in parallel between the capacitor CY1 and the chassis ground terminal FG. In order to properly guide the leakage current I1 to the chassis ground terminal FG via the resistor R1, the leakage current I1 is prevented from flowing to the secondary ground terminal SG via the resistor RR, and the resistance of the resistor R1 is preferably determined. The resistance of the resistor RR is determined. Since the leakage current I1 is shunted according to the inverse ratio of the resistance value, the resistance value of the resistor R1 is designed to be between 0.5% and 0.05% of the resistance value of the resistor RR to effectively guide most of the leakage current I1 to flow through the resistor R1. Connect to the chassis ground terminal FG and avoid the risk of electric shock to the user.

進一步地，由於電阻R1之電阻值受到上述之限制，使漏電流I1流過電阻R1時，電阻R1兩端之感測電壓訊號Vsense相對應地受限，因而較容易受到雜訊或是其他非理想效應之干擾。倘若欲排除感測電壓訊號Vsense中的雜訊以及非理想效應，請參考第6圖，第6圖為第2圖中之補償模組202之一實施例示意圖。為了方便說明，本圖中之接地端皆為機殼接地端FG。如第6圖所示，補償模組202包含有一相加器600、一補償器602以及一放大器604。在補償模組202中，相加器600用來將感測電壓訊號Vsense與電壓V1相加，以平移其直流電壓位準。補償器602用來對感測電壓訊號Vsense進行濾除雜訊以及訊號補償。放大器604則用來將補償後的感測電壓訊號Vsense進行訊號振幅放大，以輸出補償電壓訊號Vcomp。例如，補償器602可為比例積分（Proportional-Integral，PI）補償器。詳細來說，由於感測電壓訊號Vsense摻雜許多雜訊需要進行補償以及濾除，但是感測電壓訊號Vsense本身的直流電壓水平位準無法到達電路中金氧半場效電晶體的理想工作電壓。因此可先藉由相加器600與電壓V1相加來改變感測電壓訊號Vsense的水平電壓位準，以達到金氧半場效電晶體的理想工作電壓，使補償器602以及放大器604可在理想工作電壓下工作並且維持足夠的增益以及頻寬。補償器602以及放大器604可較佳地對感測電壓訊號Vsense進行濾波、補償、以及訊號放大等操作，濾除感測電壓訊號Vsense中的雜訊以及非理想效應，以產生補償電壓訊號Vcomp。Further, since the resistance value of the resistor R1 is limited by the above, when the leakage current I1 flows through the resistor R1, the sensing voltage signal Vsense across the resistor R1 is correspondingly limited, and thus is more susceptible to noise or other non- Interference with ideal effects. If the noise and non-ideal effects in the sensing voltage signal Vsense are to be excluded, please refer to FIG. 6, which is a schematic diagram of an embodiment of the compensation module 202 in FIG. For convenience of explanation, the grounding end in this figure is the chassis grounding end FG. As shown in FIG. 6, the compensation module 202 includes an adder 600, a compensator 602, and an amplifier 604. In the compensation module 202, the adder 600 is used to add the sensing voltage signal Vsense to the voltage V1 to translate its DC voltage level. The compensator 602 is configured to filter the noise and signal compensation of the sensing voltage signal Vsense. The amplifier 604 is used to amplify the signal amplitude of the compensated sensing voltage signal Vsense to output a compensation voltage signal Vcomp. For example, the compensator 602 can be a Proportional-Integral (PI) compensator. In detail, since the sensing voltage signal Vsense is doped with a lot of noise, it needs to be compensated and filtered, but the DC voltage level of the sensing voltage signal Vsense itself cannot reach the ideal working voltage of the gold-oxygen half-effect transistor in the circuit. Therefore, the level voltage level of the sensing voltage signal Vsense can be changed by the adder 600 and the voltage V1 to achieve the ideal working voltage of the gold-oxygen half-field effect transistor, so that the compensator 602 and the amplifier 604 can be ideal. Operates at operating voltage and maintains sufficient gain and bandwidth. The compensator 602 and the amplifier 604 preferably perform filtering, compensation, and signal amplification operations on the sensing voltage signal Vsense to filter out noise and non-ideal effects in the sensing voltage signal Vsense to generate a compensation voltage signal Vcomp.

因此，經過濾除雜訊、補償訊號、以及放大後的補償電壓訊號Vcomp可輸出至控制單元以產生控制訊號Vcont。請參考第7圖，第7圖為本發明實施例之故障偵測電路20的實驗結果之示意圖。如第7圖所示，補償電壓訊號Vcomp以實線標示，而控制訊號Vcont以虛線標示。當產生高電壓的補償電壓訊號Vcomp時，代表故障偵測電路20感測到有經由流入機殼接地端FG之電流所產生之感測電壓的存在，因此控制訊號Vcont輸出低電壓，不指示警示單元206執行警示功能。當補償電壓訊號Vcomp輸出為低電壓時，表示故障偵測電路20感測到經由流入機殼接地端FG之電流所產生之感測電壓非常微小或不存在，因此控制訊號Vcont輸出高電壓，指示警示單元206執行警示功能並提醒使用者。Therefore, the filtered noise removal, compensation signal, and amplified compensation voltage signal Vcomp can be output to the control unit to generate the control signal Vcont. Please refer to FIG. 7. FIG. 7 is a schematic diagram showing experimental results of the fault detecting circuit 20 according to an embodiment of the present invention. As shown in Fig. 7, the compensation voltage signal Vcomp is indicated by a solid line, and the control signal Vcont is indicated by a broken line. When the high voltage compensation voltage signal Vcomp is generated, the fault detection circuit 20 senses that there is a sensing voltage generated by the current flowing into the chassis ground FG, so the control signal Vcont outputs a low voltage without indicating an alarm. Unit 206 performs an alert function. When the compensation voltage signal Vcomp is output to a low voltage, it indicates that the fault detecting circuit 20 senses that the sensing voltage generated by the current flowing into the chassis ground FG is very small or non-existent, so the control signal Vcont outputs a high voltage, indicating The alert unit 206 performs an alert function and alerts the user.

需注意的是，前述實施例係用以說明本發明之概念，本領域具通常知識者當可據以做不同之修飾，而不限於此。例如，警示單元206可以光訊號、聲音訊號或是震動訊號等來警示使用者，其只要可達到警示功能以避免使用者觸電之危險即可。舉例來說，請參考第8及9圖，第8及9圖分別為本發明實施例之故障偵測電路80及90之變化實施例示意圖，故障偵測電路80、90為故障偵測電路20的不同實現方式，因此將相同的元件以相同的符號代表。如第8圖所示的故障偵測電路80，控制單元804包含一反相器（Inverter）INV，用以取代第2圖中的控制單元204。如第9圖所示的故障偵測電路90，控制單元904包含一電壓緩衝器（Voltage Buffer）BUF，用以取代第2圖中的控制單元204，警示單元906耦接於控制單元804與系統供應電源VDD之間，用以取代第2圖中的警示單元206。It is to be noted that the foregoing embodiments are intended to illustrate the concept of the present invention, and those skilled in the art can make various modifications without limitation thereto. For example, the warning unit 206 can alert the user by using an optical signal, an audio signal, or a vibration signal, etc., as long as the warning function can be achieved to avoid the danger of the user being shocked. For example, please refer to FIG. 8 and FIG. 9 and FIG. 8 and FIG. 9 respectively are schematic diagrams showing changes of the fault detecting circuits 80 and 90 according to an embodiment of the present invention. The fault detecting circuits 80 and 90 are fault detecting circuits 20 Different implementations, so the same elements are represented by the same symbols. As shown in the fault detection circuit 80 shown in FIG. 8, the control unit 804 includes an inverter INV instead of the control unit 204 in FIG. The fault detection circuit 90 shown in FIG. 9 includes a voltage buffer BUF for replacing the control unit 204 in FIG. 2, and the warning unit 906 is coupled to the control unit 804 and the system. The power supply VDD is supplied to replace the warning unit 206 in FIG.

綜上所述，相較於習知技術，使用者無從判斷其機殼接地端的連接是否產生故障，進一步地無法避免觸電之危險。相較之下，本發明之故障警示電路可藉由偵測單元感測接地端連接是否故障並執行警示功能來通知使用者，讓使用者可輕易地依警示功能判斷接地端的接地功能是否故障，因而得以避免觸電之危險。以上所述僅為本發明之較佳實施例，凡依本發明申請專利範圍所做之均等變化與修飾，皆應屬本發明之涵蓋範圍。In summary, compared with the prior art, the user has no way to judge whether the connection of the grounding end of the casing is faulty, and further the danger of electric shock cannot be avoided. In contrast, the fault warning circuit of the present invention can notify the user by detecting whether the ground connection is faulty and performing an alert function, so that the user can easily determine whether the grounding function of the ground is faulty according to the warning function. Therefore, the danger of electric shock can be avoided. The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should be within the scope of the present invention.

10、50‧‧‧充電器 10, 50‧‧‧ Charger

20、40、80、90‧‧‧故障警示電路 20, 40, 80, 90‧‧‧ fault warning circuit

30‧‧‧流程 30‧‧‧Process

200‧‧‧偵測單元 200‧‧‧Detection unit

202‧‧‧補償模組 202‧‧‧Compensation module

204、804、904‧‧‧控制單元 204, 804, 904‧‧‧ control unit

206、906‧‧‧警示單元 206, 906‧‧‧ warning unit

300、302、304、306、308、310‧‧‧步驟 300, 302, 304, 306, 308, 310‧‧‧ steps

600‧‧‧相加器 600‧‧‧Adder

602‧‧‧補償器 602‧‧‧ compensator

604‧‧‧放大器 604‧‧Amplifier

PG‧‧‧一次側接地端 PG‧‧‧primary ground

SG‧‧‧二次側接地端 SG‧‧‧secondary grounding terminal

FG‧‧‧機殼接地端 FG‧‧‧ chassis ground

Vsense‧‧‧感測電壓訊號 Vsense‧‧‧ sense voltage signal

Vcomp‧‧‧補償電壓訊號 Vcomp‧‧‧compensation voltage signal

Vcont‧‧‧控制訊號 Vcont‧‧‧ control signal

Vth‧‧‧臨限電壓 Vth‧‧‧ threshold voltage

CY1、CC、CF‧‧‧電容 CY1, CC, CF‧‧‧ capacitor

R1、R2、R3、R4、RR‧‧‧電阻 R1, R2, R3, R4, RR‧‧‧ resistance

M1‧‧‧金氧半場效電晶體 M1‧‧‧Gold Oxygen Half Field Effect Crystal

LED1、LED2、LED3、LED4‧‧‧發光二極體 LED1, LED2, LED3, LED4‧‧‧Lighting diode

VDD‧‧‧系統供應電源 VDD‧‧‧ system power supply

V1‧‧‧電壓 V1‧‧‧ voltage

I1‧‧‧電流 I1‧‧‧ Current

INV‧‧‧反相器 INV‧‧‧Inverter

BUF‧‧‧電壓緩衝器 BUF‧‧‧ voltage buffer

第1圖為傳統充電器之接地功能之示意圖。第2圖為本發明實施例之故障警示電路之示意圖。第3圖為本發明實施例一流程之示意圖。第4圖為本發明實施例之故障偵測電路之一變化實施例示意圖。第5圖為本發明實施例之充電器之示意圖。第6圖為第2圖中之補償模組之示意圖。第7圖為本發明實施例之故障偵測電路的實驗結果之示意圖。第8圖為本發明實施例之故障偵測電路之另一變化實施例示意圖。第9圖為本發明實施例之故障偵測電路之又一變化實施例示意圖。Figure 1 is a schematic diagram of the grounding function of a conventional charger. FIG. 2 is a schematic diagram of a fault warning circuit according to an embodiment of the present invention. FIG. 3 is a schematic diagram of a process of an embodiment of the present invention. FIG. 4 is a schematic diagram of a modified embodiment of a fault detection circuit according to an embodiment of the present invention. Figure 5 is a schematic diagram of a charger according to an embodiment of the present invention. Figure 6 is a schematic diagram of the compensation module in Figure 2. FIG. 7 is a schematic diagram showing experimental results of a fault detection circuit according to an embodiment of the present invention. FIG. 8 is a schematic diagram of another variation of the fault detection circuit according to the embodiment of the present invention. FIG. 9 is a schematic diagram of still another variation of the fault detection circuit according to the embodiment of the present invention.

Claims

一種故障警示電路，包含有：一偵測單元，耦接至一接地接腳，用來偵測一感測電壓訊號，其中該感測電壓訊號係有關於流入該接地接腳之一電流；一補償模組，耦接於該偵測單元，用來根據該感測電壓訊號產生一補償電壓訊號；一控制單元，耦接於該補償模組，用來根據該補償電壓訊號產生一控制訊號，包含有：一第一電阻，包含有一第一端，耦接於一電壓源，以及一第二端；以及一電晶體，包含有一第一端，耦接於該第一電阻之該第二端，用以輸出該控制訊號，一第二端，耦接於該補償模組，以及一第三端，耦接於該接地接腳；以及一警示單元，用來根據該控制訊號執行一警示功能；其中，當該補償電壓訊號小於或等於一臨限值時，該電晶體不導通該第一端與該第三端之間的連結，以輸出該控制訊號，使得該警示單元根據該控制訊號輸出一警示訊號以執行該警示功能，以及當該補償電壓訊號大於該臨限值時，該電晶體導通該第一端與該第三端之間的連結，以輸出該控制訊號，使得該警示單元根據該控制訊號不執行該警示功能。 A fault warning circuit includes: a detecting unit coupled to a grounding pin for detecting a sensing voltage signal, wherein the sensing voltage signal is related to a current flowing into the grounding pin; The compensation module is coupled to the detection unit for generating a compensation voltage signal according to the sensing voltage signal; a control unit coupled to the compensation module for generating a control signal according to the compensation voltage signal, The first resistor includes a first end coupled to a voltage source and a second end, and a transistor including a first end coupled to the second end of the first resistor For outputting the control signal, a second end coupled to the compensation module, and a third end coupled to the ground pin; and a warning unit for performing an alert function according to the control signal Wherein, when the compensation voltage signal is less than or equal to a threshold value, the transistor does not conduct a connection between the first end and the third end to output the control signal, so that the warning unit is based on the control signal Output a police The signal is used to perform the warning function, and when the compensation voltage signal is greater than the threshold value, the transistor turns on the connection between the first end and the third end to output the control signal, so that the warning unit is configured according to the The control signal does not perform this alert function.

如請求項1所述之故障警示電路，其中該偵測單元包含有：一感測電阻，該感測電阻之一端耦接至該接地接腳，該感測電壓訊號為該電流流經該感測電阻時所產生的跨壓。 The fault warning circuit of claim 1, wherein the detecting unit comprises: a sensing resistor, one end of the sensing resistor is coupled to the grounding pin, and the sensing voltage signal is the current flowing through the sense The voltage across the resistor is measured.

如請求項1所述之故障警示電路，其中該補償模組包含有：一補償器，用來對該感測電壓訊號進行訊號補償與雜訊消除操作，以產生一經補償之感測電壓訊號；以及一放大器，用來放大該經補償之感測電壓訊號，以產生該補償電壓訊號。 The fault warning circuit of claim 1, wherein the compensation module comprises: a compensator for performing signal compensation and noise cancellation operations on the sensed voltage signal to generate a compensated sense voltage signal; and an amplifier for amplifying the compensated sense voltage signal to generate the Compensation voltage signal.

如請求項3所述之故障警示電路，其中該補償模組另包含有：一相加器，用來將該感測電壓訊號與一參考電壓相加，以產生一電壓累加訊號，其中該補償器接收該電壓累加訊號並對該電壓累加訊號進行訊號補償與雜訊消除操作，以產生該經補償之感測電壓訊號。 The fault warning circuit of claim 3, wherein the compensation module further comprises: an adder for adding the sense voltage signal to a reference voltage to generate a voltage accumulating signal, wherein the compensation The device receives the voltage accumulating signal and performs signal compensation and noise canceling operation on the voltage accumulating signal to generate the compensated sensing voltage signal.

如請求項1所述之故障警示電路，其中該警示單元包含有：一發光單元，耦接於該第一電阻之該第二端；以及一第二電阻，包含有一第一端，耦接於該發光單元，以及一第二端，耦接於該接地接腳。 The fault warning circuit of claim 1, wherein the warning unit comprises: a light emitting unit coupled to the second end of the first resistor; and a second resistor including a first end coupled to the first end The light emitting unit and a second end are coupled to the grounding pin.

如請求項6所述之故障警示電路，其中發光單元包含有至少一個以串聯形式連接之發光二極體。 The fault warning circuit of claim 6, wherein the light emitting unit comprises at least one light emitting diode connected in series.

一種故障警示方法，包含有：偵測一感測電壓訊號；對該感測電壓訊號進行一訊號補償程序，以產生一補償電壓訊號；根據該補償電壓訊號產生一控制訊號；以及根據該控制訊號執行一警示功能。 A fault warning method includes: detecting a sensing voltage signal; performing a signal compensation procedure on the sensing voltage signal to generate a compensation voltage signal; generating a control signal according to the compensation voltage signal; and generating a control signal according to the control signal Perform a warning function.

如請求項7所述之偵測方法，其中該訊號補償程序係對該感測電壓訊號進行一濾波操作、一直流位準操作以及一放大操作。 The method of detecting according to claim 7, wherein the signal compensation program is the sensing voltage The number performs a filtering operation, a constant current level operation, and an amplification operation.

如請求項7所述之偵測方法，其中根據該補償電壓訊號產生該控制訊號織步驟包含有：將該補償電壓訊號與一臨界電壓值進行比較；當該補償電壓訊號大於該臨界電壓值時產生該控制訊號以指示執行該警示功能；以及當該補償電壓訊號小於或等於該臨界電壓值時產生該控制訊號以指示不執行該警示功能。 The detecting method of claim 7, wherein the step of generating the control signal according to the compensation voltage signal comprises: comparing the compensation voltage signal with a threshold voltage value; and when the compensation voltage signal is greater than the threshold voltage value The control signal is generated to indicate that the alert function is performed; and the control signal is generated when the compensated voltage signal is less than or equal to the threshold voltage value to indicate that the alert function is not performed.

一種故障警示電路，包含有：一偵測單元，耦接至一接地接腳，用來偵測一感測電壓訊號，其中該感測電壓訊號係有關於流入該接地接腳之一電流；一補償模組，耦接於該偵測單元，用來根據該感測電壓訊號產生一補償電壓訊號，包含有：一相加器，用來將該感測電壓訊號與一參考電壓相加，以產生一電壓累加訊號；一補償器，用來對該電壓累加訊號進行訊號補償與雜訊消除操作，以產生一經補償之感測電壓訊號；以及一放大器，用來放大該經補償之感測電壓訊號，以產生該補償電壓訊號；一控制單元，耦接於該補償模組，用來根據該補償電壓訊號產生一控制訊號；以及一警示單元，用來根據該控制訊號執行一警示功能。A fault warning circuit includes: a detecting unit coupled to a grounding pin for detecting a sensing voltage signal, wherein the sensing voltage signal is related to a current flowing into the grounding pin; The compensation module is coupled to the detecting unit for generating a compensation voltage signal according to the sensing voltage signal, comprising: an adder for adding the sensing voltage signal to a reference voltage to Generating a voltage accumulating signal; a compensator for performing signal compensation and noise canceling operations on the voltage accumulating signal to generate a compensated sensing voltage signal; and an amplifier for amplifying the compensated sensing voltage a signal is generated to generate the compensation voltage signal; a control unit coupled to the compensation module for generating a control signal according to the compensation voltage signal; and a warning unit for performing an alert function according to the control signal.