經濟部中央揉率局員工消费合作社印It A7 ____B7_^_ 五、發明説明（/ ) 《發明之領域》 本發明是一種有關於交流電源之斷電信號產生方法及 其裝置，特別是指一種藉由直接偵側交流電源端電壓狀態 之手段，而可縮短斷電偵知時間並發出信號加以適當處理 者0 《先前技越之描述》 由於大多數電子元件皆需工作於直流，因此目前一般 電子裝備亦多使用直流電作為工作電源，而此直流之工作 電源則可依不同使用埸合與條件選擇由電池供應或由市電 變壓，經整流滤波後提供使用；而為使電子設備蓮作正常 ，較重襄之電子裝置內部多於直流電源端附有一偵測電路 •以偵知直流工作電源之電歷是否不足。 習見之電壓偵測方式*乃係配合如第1圖所示之偵測 電路實施之，該偵測電路主要包括：分壓電路20、比較電 路21、參考電壓電路22及輸出電路23等部份，該分壓電路 20係銜接直流電源端，以將該待偵測之直流電壓經分壓成 一比例電壓Vx，將該比例電壓Vx與一由參考電壓電路22產 生預定之參考電壓Vy同時輸入至一比較電路21，在正常情 形下，比例電壓Vx大於參考電壓Vy，比較電路21輸出為 ”LOW” *電路工作於正常狀態•而當該偵測之直流電壓低 於預設值時，比例電壓Vx將小於參考電壓Vy時，比較電路 21輸出一"HIGH”信號，經一輸出電路23反相處理而產生一 正向警示信號Q與一負向信號d，該些警示信號經處理後 可以重置電路或以聲、光等方式顯示，提醒使用者作適當 處置。 本紙張尺度適用中國國家標準（CNS )八4規格（2丨〇><297公釐） (請先W讀背面之注$項再填寫本頁) 訂 A7 B7 五、發明説明（义） 然而，由於電池與交流整流供電之特性不同，故對於 電源電壓下降之偵知情形亦有明顯不同*就電池而言•其 供電電壓係緩慢逐漸下降，故有較足夠之反應時間作應變 ，但對交流整流之直流供電電源而言，其交流電斷電後， 由於整流電路中之濾波電容之放電作用，使直流端電壓係 随電容之放電能量而降低•但因電容器之放電曲線係圼先 緩後急非線性變化，其電壓之下降與時間之平方成正比（ 請參第2A圖所示）·亦即•隨著間之增加，該直流電壓下 降之速率愈快，如第2A圖中，假設於時間t2時交流供電中 斷·由於電容之放電使比例電壓Vx由開始下降•直至t3 時，fcb树電flSVx小於參考電壓Vy，比較電路21輸出一"HIGH 信號經一反相器反相成”LOW” （如第2B圖所示），藉K偵 知斷電情形並作出適當反應處理，其間由t2至t3所經歷之 時間，恰為電容放電電壓下降最緩慢之區域，因此，當偵 測電路由整流電路之輸出端偵知直流電壓下降至預設位準 時，其電壓已圼急速下降之狀態，造成反應時間不足，而 所剩餘之時間往往不足Μ對該電子裝備作妥善之處理，因 而資料流失·電路工作不正常之情形時有所聞。 經濟部中央樣準局負工消费合作社印装 (請先閲讀背面之注$項再填寫本頁) 有鑑於習見之電壓偵測電路有上述之缺點，發明人乃 針對該些缺點研究改進之道，終於有本發明的產生。 《發明之綜合說明》 本發明旨在提供一種交流電源之斷電信號產生方法及 其裝置，其主要目的係藉由直接偵測交流電源端之手段， 縮短發出斷電信號之決定時間。 《發明概要》 本紙張尺度逋用中國國家揉率（CNS ) Α4规格（210X297公釐） 經濟部中央搮準局負工消费合作社印装 A7 B7 _ 五、發明説明（3 ) 本發明主要係以一交流電Μ信號謓取電路直接於交流 電源端謓取交流電壓信號，並將前述交流電壓信號Κ一整 流電路整流為全波或半波之整流信號，以一第一比較器將 整流信號電歷與一第一參考電壓比較大小，藉以產生一脈 波信號，使該脈波信號輸入一充放電電路作充放電動作* 以一第二比較器比較該充放電電壓值與一第二參考電壓， 當充放電電壓值脫離該第二參考電壓規範之範圍時，第二 比較器之輸出即產生一高、低電位變化之斷電信號。 至於本發明之詳細構造、應用原理、作用與功效，則 參照下列依附圖所作之說明即可得到完全的了： 《圖示之簡單說明》 第1圖為習見之直流電壓偵測電路方塊圖。 第2Α、2Β圖為習見電源斷電偵測之波形變化圖。 第3圖為本發明交流電源之斷電信號產生方法之流程圖。 第4圖為本發明交流電源之斷電信號產生裝置之電路示 意圖。 第4Α〜4Ε圖為本發明交流電源之斷電信號產生裝置之各 實施步驟波形變化示意圖。 第5圖為本發明交流電源之斷電信號產生裝置之充放電 電路另一實施例圖。 第5Α〜5Ε圖為本發明另一充放電實施例之各步驟波形變 化示意圖。 《圖示元件與符號對照》 10——交流電壓信號謓取電路C1____電容 11----波形處理電路 Va____交流電源 ^紙張尺度適用中國國家標準（€呢）八4規格（210><297公釐) ^^1- HH ^^^1 i·— I— —MaMmmw ^^^1 I HI ^^^1 K n- ^^^1 -.¾. Λ— (請先閲讀背面之注意事項再4;^'本頁) A7 B7 111.. .整流器 112.. .第一比較器 12、121----充放電電路 13 ----信號產生電路 131.. .第二比較器 14 ----及輸出電路 R1〜R11----電阻 五、發明説明（矢）Printed by the Central Government Bureau of the Ministry of Economic Affairs, Consumer Cooperatives, It A7 ____ B7 _ ^ _ V. Description of the Invention (/) "Field of Invention" The present invention relates to a method and a device for generating a power-off signal of an AC power supply, and particularly to a borrowing method. By directly detecting the voltage status of the AC power supply side, it can shorten the detection time of the power failure and send a signal for proper processing. 0 "Description of the previous technology" Because most electronic components need to work in DC, currently the general electronic The equipment also uses DC power as the working power, and this DC working power can be supplied by the battery or changed by the commercial power according to different usage conditions and conditions, and provided after rectification and filtering. In order to make the electronic equipment work normally, More heavy electronic devices have a detection circuit inside the DC power supply terminal to detect if the electrical calendar of the DC working power supply is insufficient. The conventional voltage detection method * is implemented in conjunction with the detection circuit shown in Figure 1. The detection circuit mainly includes: a voltage divider circuit 20, a comparison circuit 21, a reference voltage circuit 22, and an output circuit 23. The voltage dividing circuit 20 is connected to the DC power terminal to divide the DC voltage to be detected into a proportional voltage Vx, and the proportional voltage Vx and a predetermined reference voltage Vy generated by the reference voltage circuit 22 at the same time. Input to a comparison circuit 21. Under normal circumstances, the proportional voltage Vx is greater than the reference voltage Vy, and the output of the comparison circuit 21 is "LOW" * The circuit works in a normal state. • When the detected DC voltage is lower than the preset value, the ratio When the voltage Vx will be less than the reference voltage Vy, the comparison circuit 21 outputs a "HIGH" signal, which is inverted by an output circuit 23 to generate a positive warning signal Q and a negative signal d. After these warning signals are processed, The circuit can be reset or displayed by sound, light, etc. to remind the user to take appropriate measures. This paper size is applicable to China National Standard (CNS) 8-4 specifications (2 丨 〇 > < 297 mm) (Please read first Back of $ Item will fill in this page) Order A7 B7 V. Description of the invention (meaning) However, due to the different characteristics of the battery and AC rectified power supply, the detection situation of the power supply voltage drop is also significantly different * As far as the battery is concerned • its power supply The voltage is slowly and gradually decreased, so there is sufficient response time to strain. However, for AC rectified DC power supply, after the AC power is cut off, due to the discharge of the filter capacitor in the rectifier circuit, the DC voltage is The discharge energy of the capacitor is reduced. However, because the discharge curve of the capacitor is first slow and then non-linear, the voltage drop is proportional to the square of time (see Figure 2A). As the DC voltage decreases, the faster the rate of decrease in DC voltage, as shown in Figure 2A, it is assumed that the AC power supply is interrupted at time t2. The proportional voltage Vx drops from the start due to the discharge of the capacitor. • By t3, the fcb tree power flSVx is less than the reference voltage Vy. The comparison circuit 21 outputs a " HIGH signal which is inverted to "LOW" by an inverter (as shown in Fig. 2B), and detects the power outage by K and makes appropriate response processing. The time from t2 to t3 is just the area where the capacitor discharge voltage drops most slowly. Therefore, when the detection circuit detects that the DC voltage drops to a preset level from the output terminal of the rectifier circuit, its voltage has dropped rapidly. Due to the state, the response time is insufficient, and the remaining time is often insufficient to properly handle the electronic equipment, so data loss and circuit operation are not uncommon. Printing (please read the note on the back before filling this page) In view of the shortcomings of the conventional voltage detection circuit, the inventor researched and improved the shortcomings of these shortcomings, and finally the invention came into being. Comprehensive Description "The present invention aims to provide a method and a device for generating a power-off signal of an AC power supply. The main purpose of the invention is to shorten the time for determining a power-off signal by directly detecting the AC power supply terminal. "Summary of the invention" This paper is in Chinese national standard (CNS) A4 size (210X297 mm). It is printed by the Central Consumers' Bureau of the Ministry of Economic Affairs, A7, B7. _5. Description of the invention (3) The present invention is mainly based on An AC power signal acquisition circuit directly obtains an AC voltage signal from an AC power terminal, and rectifies the AC voltage signal K-rectifying circuit into a full-wave or half-wave rectified signal, and uses a first comparator to record the rectified signal electronically. It is compared with a first reference voltage to generate a pulse wave signal, so that the pulse wave signal is input to a charge and discharge circuit for charge and discharge operation. A second comparator compares the charge and discharge voltage value with a second reference voltage. When the charge-discharge voltage value is outside the range of the second reference voltage specification, the output of the second comparator generates a power-off signal with high and low potential changes. As for the detailed structure, application principle, function and effect of the present invention, it can be completely completed with reference to the following description made with reference to the drawings: "Simple Description of the Figures" Figure 1 is a conventional block diagram of a DC voltage detection circuit. Figures 2A and 2B are waveform diagrams of conventional power failure detection. FIG. 3 is a flowchart of a method for generating a power-off signal of an AC power source according to the present invention. Fig. 4 is a schematic circuit diagram of a power-off signal generating device for an AC power source according to the present invention. 4A to 4E are schematic diagrams of waveform changes in each implementation step of the power-off signal generating device of the AC power supply according to the present invention. Fig. 5 is a diagram of another embodiment of the charging and discharging circuit of the power-off signal generating device of the AC power source according to the present invention. 5A to 5E are schematic diagrams of waveform changes in each step of another charging and discharging embodiment of the present invention. 《Comparison of Graphical Components and Symbols》 10——AC voltage signal extraction circuit C1____Capacitor 11 ---- Waveform processing circuit Va____AC power supply ^ Paper size applies to Chinese National Standard (€?) 8 4 specifications (210 > < 297 mm) ^^ 1- HH ^^^ 1 i · — I— —MaMmmw ^^^ 1 I HI ^^^ 1 K n- ^^^ 1 -.¾. Λ— (Please read the first Note again 4; ^ 'this page) A7 B7 111... Rectifier 112... First comparator 12, 121 ---- charge and discharge circuit 13 ---- signal generation circuit 131... Second comparison 14 ---- and output circuit R1 ~ R11 ---- resistance V. Description of the invention (yao)
Vb----整流電歷Vb ---- rectified calendar
Vc----第一參考電壓Vc ---- the first reference voltage
Vd----脈波Vd ---- pulse
Ve、Ve ’...充放電壓信號Ve, Ve ’... charge and discharge voltage signals
Vf----第二參考電歷Vf ---- second reference calendar
Vf....第二參考電壓Vf .... second reference voltage
Vg----第二比較器輸出電位 《較佳具體實施例之描述》 第3圖為本發明交流電源之斷電信號產生方法之流程 圖*其首先謓取一交流電源之交流電壓信號並將之整流為 全波或半波之整流信號，再利用一第一參考電壓與前述之 整流信號電壓比較大小，藉以產生一脈波信號，以前一步 驟所產生之脈波信號作為一充放電電路的充放電依據，當 前述充放電结果之電JK值脫雛一既定之第二參考電壓範圍 時產生一斷電信號。 由圖示可知：開始偵測時，首先直接由交流電源端取 得交流電壓；將該交流電壓經適當分壓並加以骛流，使之 成為一全波或半波之整流電壓，再由一參考電壓電路產生 一數值小於整流電壓之第一直流參考電壓。 將前述整流電壓與第一直流參考電壓同時輸入第一比 較器，藉第一比較器比較整流電壓與第一直流參考電壓， 並於整流電壓大於該直流參考電壓時輸出定值高電位，而 於整流電壓小於直流參考電壓時輸出低電位，藉此連續之 高低電位形成一脈波信號。 充放電路於接受前述脈波信號後•於脈波信號為高電 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐〉 (請先閲讀背面之注$項再填寫本頁) 訂 經濟部中央標準局貝工消费合作社印裝 A7 B7 五、發明説明（纟） 位時執行充電動作，於脈波信號為低電位時執行放電動作 ，以形成一充放電壓信號。將前述充放電壓信號與一第二 直流參考電壓同時輸入第二比較器比較，使第二比較器於 充放電壓信號小於第二直流參考電壓時，表示供電持鑕正 常，第二比較器輸出信號不產生變化，相關處理電路亦未 受觸發，而若充放電壓信號大於第二直流參考電壓時*則 表示交流電源端供電中止，此時第二比較器輸出一高低電 壓變化信號，Μ觸發預定相關處理電路作適當處置。 第4圖為本發明交流電源之斷電信號產生裝置之電路 示意圖，由其配合第4Α至4Ε圖所示，明顯可看出：依本實 施例中所述之電路主要完整結構約略包括：交流電壓信號 謓取電路10、波形處理電路11、充放電電路12、信號產生 電路13、及輸出電路14等部份*其中交流電壓信號謓取電 路10内包含一由係由電阻Rl、R2組成之分壓電路裝置，主 要功能係將電源電壓V經過分壓而得所需適當數值之分壓 電壓並輸入後續之波形處理電路11內，波形處理電路11主 要包含一整流器111與一第一比較器112，前啤交流電壓 信號讀取電路10輸出之分壓電壓經整流器111整流成一整 流電壓（此處係Μ橋式整流出全波為代表，Μ其它方式整 流出全波甚或半波亦可），此時其電應之波形由交流電源 sl點之正弦波（如第4Α圖所示）改變為整流後b點之整流 電壓Vb波形（如第4B圖所示），而此整流電歷Vb再經電壓 再經電阻R3、R4分壓，與另一由電阻R5、R6自Vcc電源分 壓而得c點之第一參考電壓Vc共同輸入第一比較器112， 而該第一參考電壓Vc之大小係低於整流電歷Vb之峰值電壓 本紙張尺度適用中國國家標準（CNS ) A4说格（210X297公釐） 請 先 閲 讀 背 Λ 之 注 項 再 f 本 頁 訂 經濟部中央揉準局貝工消费合作社印製 經濟部中央橾準局貝工消费合作社印製 A7 B7 五、發明説明（G ) ，使第一比較器112之輸出d點輸出一如第4C圖所示之脈 波Vd，該第一比較器112之輸出脈波Vd之高、低電歷位部 份係以整流電壓Vb相較於第一參考電壓Vc而得，當整流電 壓Vb大於第一參考電壓Vc時，脈波Vd為低電位部份，而整 流電壓Vb小於第一參考電壓Vc時，脈波Vd為高電位部份， 此脈波信號Vd館至一由電阻R7與電容C1組成之充放電電路 12，當脈波信號Vd為高電位時，充放電電路12為充電狀態 ，當脈波信號Vd為低電位時，充放電電路12為放電狀態， 藉由充放電動作*即形成如第4D圖之充放電應信號Ve，將 此充放電壓信號Ve饋至一信號產生電路13，與另一由電阻 R8、R9自Vcc電源分壓而得之第二參考電壓Vf同時輸入一 第二比較器131，正常情形下，第二參考電歷Vf係保持大 於充放電壓信號Ve，此時第二比較器131之輸出G點之電 位Vg為一高電位，附靨之輸出電路14無法觸發動作，假設 在時間tO時交流電源V中斷，則整流電壓Vb隨之停止，波 形處理電路11之輸出Vd即保持於高電位，由充放電電路12 充放電形成之充放電壓信號Ve則因不斷充電而與電壓隨時 間上昇，當充放電壓信號Ve上昇至超過第二參考電JigVf時 (此時時間為tl)，信號產生電路13之輸出電位Vg則由高 電位改變為低電位（如第4E圖所示），附靥之輸出電路14 隨之觸發導通，使相關之警示電路或其它處理裝置開始動 作。 上述實施例中之脈波信號Vd之振幅（髙電位值）與待 測之交流電壓值無關，而係由第一比較器112之工作電壓 而定，而第二參考電壓Vf值愈低時，由交流電源斷電至偵 本紙張尺度適用中國國家標準（CNS > Λ4規格（210X297公羞） (請先閲讀背面之注項再填寫本頁) 、νβ A7 B7 五、發明説明（·〗） 測出之時間（tl-to)亦愈短•約可在電源半週波期偵知 ，其反應時間較習用者快出許多。 第5圖為本發明交流電源之斷電信號產生裝置之充放 電電路另一實施例圖，由其配合第5A至5E圖所示可知：本 實施例之充放電電路121 *係於電容C1旁側另並聯一電阻 經濟部中央揉準局貝工消费合作社印裝 (請先閲讀背面之注意事項再填寫本頁) R11，當脈波信號Vd為高電位時，充放電電路121為放電 狀態，當脈波信號Vd為低電位時，充放電電路121反為充 電狀態*藉由充放電動作，即形成如第5D圖之充放電歷信 號Ve’，將此充放電歷信號Ve’饋至信號產生電路13，與 第二參考電壓Vf同時輸入第二比較器131，正常情形下* 第二參考電壓Vf係保持小於充放電壓信號Vef，此時第二 比較器131輸出G點之電位Vg為一高電位，附靥之輸出電 路14無法觸發動作，假設在時間tO’時交流電源V中斷， 則整流電壓Vb随之停止，波形處理電路11之輸出Vd即保持 於高電位，由充放電電路121充放電形成之充放電壓信號 Ve’則因不斷放電而使電壓随時間下降，當充放電壓信號 Ve’下降至超過第二參考電壓Vf時（此時時間碎tl’）， 信號產生電路13之輸出電位Vg則由高電位改變為低電位（ 如第4E圖所示），附靥之輸出電路14隨之觸發導通，使栢 關之譬示電路或其它處理裝置開始動作。 上述實施例中，由於電容器具有先鍰後急非線性變化 之放電特性，故適當的設定第二參考電壓Vf值•使之愈接 近充放電壓信號Ve’時*其由交流電源斷電至偵測出之時 間（tl’一 to’）亦可愈縮短。 由上所述可知，本發明之交流電源之斷電信號產生方 本紙張尺度適用中國國家標準（CNS)A4規格（210X297公釐） A7 B7 五、發明説明U ) 法及其裝置確實具有縮短偵知交流電源端斷電狀態之時間 並迅速發出斷電信號加以處理之功效，而其並未見諸公開 使用，合於專利法之規定，懇請賜淮專利，實為德便。 (請先閲讀背面之注意事項再填寫本頁) 訂 經濟部中央標準局貝工消费合作社印装 本紙張尺度適用中國國家標準（CNS ) A4規格（210 X 297公釐）Vg ---- the output potential of the second comparator "Description of the preferred embodiment" Figure 3 is a flowchart of the method for generating the power-off signal of the AC power source according to the present invention. * First, it takes an AC voltage signal of an AC power source and It is rectified into a full-wave or half-wave rectified signal, and then a first reference voltage is compared with the aforementioned rectified signal voltage to generate a pulse wave signal. The pulse wave signal generated in the previous step is used as a charge and discharge circuit. According to the charging and discharging basis, a power-off signal is generated when the electric JK value of the foregoing charging and discharging result is removed from a predetermined second reference voltage range. As can be seen from the figure: when the detection is started, the AC voltage is first obtained directly from the AC power terminal; the AC voltage is appropriately divided and circulated to make it a full-wave or half-wave rectified voltage, and then a reference The voltage circuit generates a first DC reference voltage having a value smaller than the rectified voltage. Inputting the aforementioned rectified voltage and a first DC reference voltage simultaneously to a first comparator, comparing the rectified voltage with the first DC reference voltage by the first comparator, and outputting a constant high potential when the rectified voltage is greater than the DC reference voltage, When the rectified voltage is less than the DC reference voltage, a low potential is output, so that a continuous high and low potential forms a pulse signal. The charging and discharging circuit after receiving the aforementioned pulse wave signal • The pulse wave signal is high electricity. The paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) (Please read the note on the back before filling this page). Printed by the Central Standards Bureau of the Ministry of Economic Affairs, Shellfish Consumer Cooperative, printed A7 B7 V. Description of the invention (纟) Perform the charging action when the position is low, and perform the discharging action when the pulse signal is at a low potential to form a charging and discharging voltage signal. The voltage signal is input to a second comparator for comparison with a second DC reference voltage at the same time, so that when the charge / discharge voltage signal is smaller than the second DC reference voltage, it means that the power supply is normal, and the output signal of the second comparator does not change. The relevant processing circuit has not been triggered, and if the charging / discharging voltage signal is greater than the second DC reference voltage *, it means that the AC power supply is suspended. At this time, the second comparator outputs a high and low voltage change signal, and M triggers the predetermined relevant processing circuit. Fig. 4 is a schematic circuit diagram of the power-off signal generating device of the AC power source of the present invention. It can be clearly seen that according to the main complete structure of the circuit described in this embodiment, it includes: AC voltage signal extraction circuit 10, waveform processing circuit 11, charge and discharge circuit 12, signal generation circuit 13, and output circuit 14, etc. * Among them, the AC voltage signal extraction circuit 10 includes a voltage dividing circuit device composed of resistors R1 and R2. The main function is to divide the power supply voltage V to obtain a desired voltage value and input the subsequent voltage. In the waveform processing circuit 11, the waveform processing circuit 11 mainly includes a rectifier 111 and a first comparator 112. The divided voltage output by the front beer AC voltage signal reading circuit 10 is rectified by the rectifier 111 into a rectified voltage (here, M The bridge-type rectified full wave is the representative, and the other methods can also be used to rectify the full wave or even half wave. At this time, the waveform of the electric response should be changed from the sine wave of the AC power sl point (as shown in Figure 4A) to rectified. The rectified voltage Vb waveform at point b (as shown in Figure 4B), and this rectified electrical calendar Vb is then divided by the voltages of resistors R3 and R4, and another divided by the resistors R5 and R6 from the Vcc power supply to obtain c. First parameter The voltage Vc is input to the first comparator 112 in common, and the magnitude of the first reference voltage Vc is lower than the peak voltage of the rectified calendar Vb. The paper size applies the Chinese National Standard (CNS) A4 grid (210X297 mm). Please read first Note the item of Λ and f on this page. Printed by the Central Ministry of Economic Affairs of the Central Bureau of Quasi Bureau Shellfish Consumer Cooperatives. Printed by the Central Ministry of Economic Affairs of the Central Bureau of Quasi Bureau Shellfish Consumer Cooperatives. Printed A7 B7 5. Invention Description (G), the first comparator 112 The output point d outputs a pulse wave Vd as shown in FIG. 4C. The high and low electrical digits of the output pulse wave Vd of the first comparator 112 are compared with the first reference voltage Vc by the rectified voltage Vb. Therefore, when the rectified voltage Vb is greater than the first reference voltage Vc, the pulse wave Vd is a low-potential portion, and when the rectified voltage Vb is less than the first reference voltage Vc, the pulse wave Vd is a high-potential portion. This pulse wave signal Vd The charge-discharge circuit 12 is composed of a resistor R7 and a capacitor C1. When the pulse wave signal Vd is high, the charge-discharge circuit 12 is charged. When the pulse wave signal Vd is low, the charge-discharge circuit 12 is discharged. The state is formed by the charge and discharge operation * The charge and discharge response signal Ve in the 4D diagram is fed to a signal generating circuit 13 and a second reference voltage Vf obtained by dividing the voltage from the Vcc power source with the resistors R8 and R9 is simultaneously input into a second Comparator 131. Under normal circumstances, the second reference calendar Vf remains larger than the charge-discharge voltage signal Ve. At this time, the potential Vg of the output G point of the second comparator 131 is a high potential, and the attached output circuit 14 cannot be triggered. The operation, assuming that the AC power supply V is interrupted at time tO, the rectified voltage Vb is stopped, the output Vd of the waveform processing circuit 11 is maintained at a high potential, and the charging and discharging voltage signal Ve formed by the charging and discharging circuit 12 is continuously The charging and voltage rises with time. When the charge-discharge voltage signal Ve rises above the second reference voltage JigVf (the time is tl at this time), the output potential Vg of the signal generating circuit 13 changes from a high potential to a low potential (such as (Shown in Figure 4E), the attached output circuit 14 is subsequently turned on, so that the related warning circuit or other processing device starts to operate. The amplitude (实施 potential value) of the pulse wave signal Vd in the above embodiment has nothing to do with the AC voltage value to be measured, but is determined by the operating voltage of the first comparator 112, and the lower the second reference voltage Vf value, From AC power failure to paper size, Chinese national standards (CNS > Λ4 specification (210X297)) (please read the note on the back before filling this page), νβ A7 B7 V. Description of invention (·) The measured time (tl-to) is also shorter. • It can be detected during the half-cycle period of the power supply, and its response time is much faster than the user. Figure 5 shows the charging and discharging of the power-off signal generating device of the AC power supply according to the present invention. Another embodiment of the circuit is shown in Figures 5A to 5E. The charging and discharging circuit 121 of this embodiment is shown on the side of the capacitor C1 and is connected in parallel with a resistor. It is printed by the Central Bureau of the Ministry of Economic Affairs. (Please read the precautions on the back before filling in this page) R11, when the pulse wave signal Vd is high potential, the charge and discharge circuit 121 is discharged, and when the pulse wave signal Vd is low potential, the charge and discharge circuit 121 is reversely charged State * by charge and discharge action As shown in FIG. 5D, the charge-discharge history signal Ve 'is fed to the signal generating circuit 13 and input to the second comparator 131 at the same time as the second reference voltage Vf. Under normal circumstances, the second reference voltage Vf It is kept smaller than the charging and discharging voltage signal Vef. At this time, the potential Vg at point G of the second comparator 131 is a high potential, and the attached output circuit 14 cannot trigger the action. Assuming that the AC power supply V is interrupted at time tO ′, the rectification is performed. The voltage Vb then stops, and the output Vd of the waveform processing circuit 11 is maintained at a high potential. The charge-discharge voltage signal Ve ′ formed by the charge-discharge circuit 121 is discharged and the voltage decreases with time due to continuous discharge. When the charge-discharge voltage signal When Ve 'falls below the second reference voltage Vf (time is broken at this time tl'), the output potential Vg of the signal generating circuit 13 is changed from a high potential to a low potential (as shown in FIG. 4E), and the attached output circuit 14 Continuity is triggered accordingly, so that the example circuit or other processing device of Baiguan starts to operate. In the above embodiment, because the capacitor has a discharge characteristic of non-linear change first, then the second is set appropriately. Measure the voltage Vf value • When it is closer to the charge-discharge voltage signal Ve '*, the time from when the AC power is turned off to detection (tl'-to') can also be shortened. As can be seen from the above, the present invention AC power supply power-off signal generator The paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) A7 B7 V. Description of the invention U) method and its device does have a shortened time to detect the power-off status of the AC power supply And quickly send out the power-off signal to process the effect, but it has not been used in public, in line with the provisions of the patent law, please petition Huai patent, it is a virtue. (Please read the precautions on the back before filling out this page) Order Printed by the Central Standards Bureau of the Ministry of Economic Affairs and printed by the Shellfish Consumer Cooperatives This paper is sized for the Chinese National Standard (CNS) A4 (210 X 297 mm)