456137 A7 _____B7 _ 五、發明說明（f ) 本發明之背景 1·發明領域 本發明大體上係有關於電話線介面電路之領域，特別 是有關於不具鉤鍵開關之電話線介面電路。 2·相關技藝說明 一夠鍵開關決定一電話裝置（例如數據機）於離線或 佔線時允許或不允許直流線電流流入此裝置。鉤鍵開關過 去被視爲爲電話線介面電路之基本元件。圖式1中所示爲 一習知技術之電話線介面電路利用繼電器6作爲鉤鍵開關 。繼電器6被連接至電話線（未圖示出）經一標準橋式二 極體4再連接至T i p及R i ng信號線。該等τ 1 p及 R i n g信號亦經端子A及B連接至振鈴檢測電路（未圖 示出）。繼電器6被廣泛用作鉤鍵開關，此由於其端子間 具有極低阻抗。然而’繼電器6體積龐大及動作時於一次 電路需要大量的功率。此外，當此裝置離線或佔線時，將 於繼電器6之端子之間產生不該有之高電壓火花。注意繼 電器6可完全地將數據機電路2與電話線隔斷。 如圖式2所示’於習知技術中電晶體8常用於鉤鍵開 關，但電晶體8亦產生一些不想要之結果。特別是，於典 型鉤鍵開關應用中，電晶體8於T i p與R i n g端子間 產生不該有之壓降，及電話線亦產生大量功率消耗、傳送 信號之失真、及隨著D C線電流變化而導致回流損失很大 之改變。應注意的是，雖圖中所示出爲F E T電晶體，但 4 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） <請先閱讀背面之注意事項再填寫本頁)456137 A7 _____B7 _ V. Description of the invention (f) Background of the invention 1. Field of the invention The present invention relates generally to the field of telephone line interface circuits, and in particular to telephone line interface circuits without hook switches. 2. Related technical description A key switch determines whether a telephone device (such as a modem) allows or does not allow DC line current to flow into the device when it is offline or busy. Hook switches were previously considered to be the basic components of telephone line interface circuits. Shown in Figure 1 is a conventional telephone line interface circuit using a relay 6 as a hook switch. The relay 6 is connected to a telephone line (not shown) via a standard bridge diode 4 and then to the T i p and R i ng signal lines. These τ 1 p and R i n g signals are also connected to a ringing detection circuit (not shown) via terminals A and B. The relay 6 is widely used as a hook switch because of its extremely low impedance between the terminals. However, the 'Relay 6' is bulky and requires a large amount of power in a single circuit during operation. In addition, when this device is offline or busy, an undesirably high voltage spark will be generated between the terminals of the relay 6. Note that the relay 6 can completely isolate the modem circuit 2 from the telephone line. As shown in Figure 2, 'transistor 8 is commonly used for hook switch in the conventional technology, but transistor 8 also produces some unwanted results. In particular, in a typical hook switch application, the transistor 8 generates an undesired voltage drop between the T ip and Ring terminals, and the telephone line also generates a large amount of power consumption, the distortion of the transmitted signal, and the DC line current Changes resulting in large changes in backflow losses. It should be noted that although the FET transistor is shown in the figure, 4 paper sizes are applicable to China National Standard (CNS) A4 (210 X 297 mm) < Please read the precautions on the back before filling this page )
I II--— —--II---I 經濟部智慧財產局員工消費合作社印製 A7 456137 _B7_ 五、發明說明（>") 亦可能使用雙載子電晶體。此外’與圖式1中之繼電器電 路相同，電晶體8可完全地將數據機電路2與電話線隔斷 〇 再者，爲有效地動作，用作鉤鍵開關之電晶體必需工 作於飽和區，及其需維持線電流全額輸出°雖然當電流於 2 0 mA時維持電晶體飽和並不困難，但當線電流增加到 1 0 0 m A時，維持電晶體飽和將是一項挑戰。電晶體開 關所產生之阻抗亦將使典型結合電子感應器電路（亦已知 爲"電流保持電路〃）之D C操作電壓降低。因此’對鉤 鍵開關開關作改良有其需求性。 本發明槪要 依本發明，其使用一種新穎的電子感應器電路，其由 電話線吸取所需D C (直流）電流構成迴路電流，以對中 心局端（或交換機端）顯示電話裝置（亦即數據機）已佔 用此線路。電子感應器電路之電晶體用以執行鉤鍵開關之 功能’因此可避免導入對此裝置的A C (交流）信號路徑 之不該有的阻抗。爲了離線，此電子感應器電晶體（當接 收一控制信號時）停止由中心局端吸取迴路電流’以顯示 其於離線狀態。與開關不同的是，本發明以啓動及停止D C電流，但整個電路仍維持與電話線連接來運作。 於一種組態中，低電流電晶體被加入與A C阻抗網路 (通常6 0 Q歐姆）串聯，以當此裝置離線時，將此網路 與電話線隔斷。依此方式，藉由產生一控制電壓以將電子 (請先閱讀背面之注意事項再填寫本頁) --------訂---------, 經濟部智慧財產局員工消費合作社印製 紙張尺度舶巾關緖·ί7^)Α4祕⑵Q χ - 4561 37 A7 經濟部智慧財產局員工消費合作杜印製 B7 五、發明說明（汐） 感應器啓動，此電話線將被〃佔線〃使用，及線路電流開 始流過此電晶體，因此達到〃接聽〃狀態。於第二個實施 例中’使用二個電晶體執行與單一電晶體相同之功能。然 而，此兩個電晶體的實施例，可對失真及其他設計考量具 有更佳之彈性。 圖式簡要說明 本發明之確實的特色、目地與優點，在以下列圖式作 詳細說明描述後將變爲極淸楚，於所有圖式中，相同參考 標號皆表示相同元件，及其中：I II --- --- II --- I Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 456137 _B7_ V. Description of Invention (> ") It is also possible to use a bipolar transistor. In addition, as with the relay circuit in Figure 1, the transistor 8 can completely isolate the modem circuit 2 from the telephone line. Furthermore, in order to operate effectively, the transistor used as a hook switch must work in the saturation region And it needs to maintain the full output of the line current. Although it is not difficult to maintain the transistor saturation when the current is at 20 mA, it will be a challenge to maintain the transistor saturation when the line current increases to 100 m A. The impedance generated by the transistor switch will also reduce the DC operating voltage of a typical integrated electronic sensor circuit (also known as " current holding circuit "). Therefore, the improvement of the hook switch has its demand. The present invention is based on the present invention, which uses a novel electronic sensor circuit that draws the required DC (direct current) current from the telephone line to form a loop current to display the telephone device (ie, the central office (or exchange)). Modem) already occupied this line. The transistor of the electronic sensor circuit is used to perform the function of a hook switch ', so it is possible to avoid introducing an unacceptable impedance to the A C (Alternating Current) signal path of the device. In order to go offline, the electronic sensor transistor (when receiving a control signal) stops drawing the loop current from the central office terminal to show that it is offline. Different from a switch, the present invention operates by starting and stopping DC current, but the entire circuit is still connected to a telephone line. In one configuration, a low current transistor is added in series with the AC impedance network (usually 60 Q ohms) to isolate this network from the telephone line when the device is offline. In this way, the electrons are generated by generating a control voltage (please read the precautions on the back before filling out this page) -------- Order ---------, Intellectual Property Bureau, Ministry of Economic Affairs Printed paper scales printed by employee consumer cooperatives Guan Xu · 7 ^) Α4 secret Q χ-4561 37 A7 Employee cooperation of Intellectual Property Bureau of the Ministry of Economic Affairs Du printed B7 5. Description of invention (Xi) The sensor is activated, and this telephone line will It is used by the busy line, and the line current starts to flow through this transistor, so it is in a state of being answered. In the second embodiment ', two transistors are used to perform the same function as a single transistor. However, the two transistor embodiments have better flexibility for distortion and other design considerations. BRIEF DESCRIPTION OF THE DRAWINGS The exact features, purpose, and advantages of the present invention will become extremely clear after the detailed description of the following drawings. In all the drawings, the same reference numerals indicate the same elements, and among them:
圖式1爲習知技術使用繼電器作爲鉤鍵開關的電話線 介面電路之方塊圖D 圖式2爲習知技術使用電晶體作爲鉤鍵開關的電話線 介面電路之方塊圖。 圖式3爲本發明第一個實施例之槪要圖。 圖式4爲本發明第二個實施例之槪要圖。 圖式5爲本發明第三個實施例之槪要圖。 主要部份代表符號之簡要說明 2 數據機電路（裝置） 4 橋式二極體 6 繼電器 8 電晶體 10電晶體 _ 6 本‘、氏浪A過用t國國家標準規格C挪公 -----—------0--------訂---------線. (請先閱讀背面之注意事項再填寫本頁) A7 456137 _______B7__ 五、發明說明（t ) 1 2 控制器 1 6 電晶體 18 電晶體 2 0 控制器 2 6 電晶體 較佳實施例之詳述 下列說明提供給任何熟習此項技術者使其可製成及使 用本發明，及闡述由發明者所思及之用以執行本發明之最 佳模式。然而，各種不同變更對那些熟知此技術者仍顯而 易見的，因爲本發明之基本原理已於此作詳細定義，以提 供一種無先前技術標準的鉤鍵開關之電話線介面電路。 本發明現將參照圖式3作說明。電晶體1 〇被連接於 數據機電路10(或其他電話裝置）與橋式二極體4間。 此電晶體1 0爲電子感應器電路之一部份’其餘部份未作 圖示，但是在此技術中其結構已爲熟知的。此電子感應器 的電晶體10用以執行鉤鍵開關之功能’因此可避免在此 數據機裝置2的A C信號路徑上導入不該有的阻抗。此電 晶體1 0其爲電壓控制之電流源。當離線時，電晶體1 〇 (當由控制器12接收控制信號），即停止由中心局端吸 入迴路電流，以顯示現於離線狀態。與開關不同的是’本 發明操作方式爲藉由啓動與停止D C電流，然而整個電路 仍保持連接於電話線上。依此方式，藉由控制器1 2產生 控制信號以將電晶體1 0導通，此電話線將被〃佔線"使 7 {請先閱讀背面之注意事項再填寫本頁) --------訂—-------線 經濟部智慧財產局員工消費合作社印製 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） A7 456137 __B7_ 五、發明說明（<) 用，及藉此啓動線電流過電晶體1 0，因此達到"接聽" 使用狀態。於典型的美國電話系統，電晶體1 0將必須吸 取約1 7 mA之電流，以達到接聽之狀態。 控制器1 2爲可以程式設定，以設定由電晶體1 0所 吸取迴路電流値。例如，對吸取多少之迴路電流才顯示接 聽狀態，很多國家具有不同標準，控制器1 2可由裝置設 計者以程式設定，以於所需之電話環境下作正確之操作， 而不需重新設計整個電路。 本發明之第二個實施例如圖式4中所示。其使用二個 電晶體1 6，1 8吸取迴路電流，而不是一個電晶體。控 制器2 0控制電晶體1 6，1 8兩者，及決定由電話線吸 取之迴路電流大小。然而每一個電晶體具有稍微不同之功 能。第一個電晶體1 6爲用以吸取所需大部份D C電流， 以顯示接聽之狀態（電晶體1 6作爲〃佔線使用〃指示器 )。第二個電晶體18僅吸取足夠作適當偏壓之DC電流 。由數位至類比（D/A)編解碼器（C 0 D E C )之A C信號被加至第二個電晶體1 8之基極，及因此第二個電 晶體1 8依A C輸入信號對D C信號作調變，及此作爲數 據機傳送器之驅動器。由於成本及性能之考量，本發明者 判斷兩個電晶體是較佳的。因使用兩個電晶體，一個可用 於傳送器之驅動器，及另一個可用於佔線指示。第一個電 晶體可爲N P N電晶體及第二個電晶體可爲P N P電晶體 〇 本發明之第三個實施例如圖式5中所示。對一些應用 8 (請先閱讀背面之注意事項再填寫本頁) --------訂--------線 經濟部智慧財產局員工消費合作社印製 本紙張尺度適用中國國家標準（CNS)A4規格（210x 297公釐） A7 456137 _B7__ 五、發明說明（b) ，第三個電晶體2 6可用作開關以隔離一些電路元件，以 滿足漏電流規定及符合其他相關技術規範。第三個電晶體 2 6並不完全是繼電器或實際開關，因爲其未與電話線完 全隔斷。然而，其將電路作充份隔離，以提供較佳之漏電 流保護。 熟知此項技術者將可認知，對上述較佳實施例所作不 同變更及修改仍屬於本發明之精神與範疇中。因此，必需 瞭解的是，於附加的申請專利範圍之範疇中，本發明可以 不同於在此所特定描述之方式加以實施。 I----- I .^i----- - 訂---I----*線， <請先閱讀背面之注意事項再填寫本頁) 經濟部智慧財產局員工消費合作社印製 本紙張尺度適用中國國家標準（CNS)A4規格（21〇x 297公釐）Figure 1 is a block diagram of a conventional telephone line interface circuit using a relay as a hook key switch. Figure 2 is a block diagram of a conventional telephone line interface circuit using a transistor as a hook key switch. Figure 3 is a schematic diagram of the first embodiment of the present invention. FIG. 4 is a summary view of a second embodiment of the present invention. Figure 5 is a schematic diagram of a third embodiment of the present invention. A brief description of the main parts of the symbols 2 Modem circuit (device) 4 Bridge diode 6 Relay 8 Transistor 10 Transistor _ 6 books', Shi Lang A used t National standard C Norgo --- ------------ 0 -------- Order --------- line. (Please read the precautions on the back before filling this page) A7 456137 _______B7__ 5. Description of the invention (T) 1 2 controller 1 6 transistor 18 transistor 2 0 controller 2 6 detailed description of a preferred embodiment of the transistor The following description is provided to anyone skilled in the art to make and use the invention, and The best mode contemplated by the inventors for carrying out the invention is described. However, various changes will still be apparent to those skilled in the art, since the basic principles of the present invention have been defined in detail herein to provide a telephone line interface circuit without the hook switch of the prior art standard. The invention will now be described with reference to Figure 3. The transistor 10 is connected between the modem circuit 10 (or other telephone device) and the bridge diode 4. This transistor 10 is a part of the electronic sensor circuit. The rest is not shown, but its structure is well known in the art. The transistor 10 of the electronic sensor is used to perform the function of a hook switch. Therefore, it is possible to prevent an unnecessary impedance from being introduced into the AC signal path of the modem device 2. This transistor 10 is a voltage-controlled current source. When offline, the transistor 10 (when the control signal is received by the controller 12) stops drawing the loop current from the central office to show that it is offline. Unlike the switch, the operation mode of the present invention is to start and stop the DC current, but the entire circuit remains connected to the telephone line. In this way, by the control signal generated by the controller 12 to turn on the transistor 10, the telephone line will be occupied. "Please read the precautions on the back before filling this page) ----- --- Order -------- Printed by the Consumers' Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. The paper is printed in accordance with China National Standard (CNS) A4 (210 X 297 mm) A7 456137 __B7_ <) use, and thereby start the line current over the transistor 10, so that the " answer " use state is reached. In a typical American telephone system, the transistor 10 will have to draw a current of about 17 mA to reach the answering state. The controller 12 can be programmed to set the loop current 値 drawn by the transistor 10. For example, how much loop current is drawn before the answer status is displayed. Many countries have different standards. The controller 12 can be programmed by the device designer to perform the correct operation in the required telephone environment without redesigning the entire system. Circuit. A second embodiment of the present invention is shown in FIG. It uses two transistors 16 and 18 to draw the loop current instead of one transistor. Controller 20 controls both transistors 16 and 18, and determines the amount of loop current drawn by the telephone line. However, each transistor has a slightly different function. The first transistor 16 is used to draw most of the DC current required to display the status of the answer (transistor 16 is used as a 〃busy 〃 indicator). The second transistor 18 only draws a DC current sufficient for proper biasing. The AC signal from the digital to analog (D / A) codec (C 0 DEC) is added to the base of the second transistor 18, and therefore the second transistor 18 compares the DC signal with the AC input signal For modulation, and as the driver of the modem transmitter. Due to cost and performance considerations, the inventors have judged that two transistors are better. Since two transistors are used, one can be used for the driver of the transmitter, and the other can be used for the busy indication. The first transistor may be an N P N transistor and the second transistor may be a P N P transistor. A third embodiment of the present invention is shown in FIG. 5. For some applications 8 (Please read the notes on the back before filling out this page) -------- Order -------- Printed by the Consumers' Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs This paper is applicable to China National Standard (CNS) A4 specification (210x 297 mm) A7 456137 _B7__ 5. Description of the invention (b), the third transistor 2 6 can be used as a switch to isolate some circuit components to meet the leakage current requirements and other relevant requirements specifications. The third transistor 26 is not exactly a relay or actual switch because it is not completely disconnected from the telephone line. However, it fully isolates the circuit to provide better leakage current protection. Those skilled in the art will recognize that different changes and modifications to the above preferred embodiments still belong to the spirit and scope of the present invention. Therefore, it must be understood that, within the scope of the appended patent application scope, the present invention may be implemented in a manner different from that specifically described herein. I ----- I. ^ I ------Order --- I ---- * line, < Please read the notes on the back before filling out this page) Employee Cooperatives, Intellectual Property Bureau, Ministry of Economic Affairs The printed paper size is applicable to China National Standard (CNS) A4 (21 × 297 mm)