1320903 九、發明說明： 【發明所屬之技術領域】 >本發明一般地涉及資料登錄和開關電路，更具體而 p涉及使用電谷感應觸摸板的開關和矩陣開關板。 【先前技術】 開關、矩陣開關板、和小鍵盤在我們的曰常生活中 是非常普及的。例#，電話（包括有〉繩電話、無繩電話 、和無線電話）具有用於輸入電話號碼和其他資訊或功 能（例如常撥號碼、通訊錄、快捷撥號等）的數位鍵盤 。個人數位助理（PDA)具有用於輪入命令和資訊的字 母數位鍵盤。甚至簡單的電子設備都可能具有一個或多 個用於控制其電源、操作模式等的開關。 ^鍵盤或鍵盤中的開關或鍵通常包括雇足彼此相 dr;觸的導體。至少-片導體是活動的且通常 广彈活動的片被按壓時，它接觸另—片導 活動的導體片的上部通常覆篕 復有^邑、·彖材科，例如塑膠、 2專。矩陣開關板或鍵盤可以包括 關或鍵的陣列。 m n ^ 分常關和鍵盤均具有？動部分’這些可動部 按壓之特別地’開關㈣彈簧可能在重複 件的折斷。機械開關還易受不利環境條 能造二關可能造成開關失靈’以及潮濕可 或機===:'，從而使它們的電氣和/ 差機械開關和鍵盤通常龐大且笨重。而 6 1320903 機械開關和鍵盤通常具有剛性或半剛性的結構。這 性f得機械開關和鍵盤不適合-些需要諸如體積 小、重量輕、和易於存放的特性的應用。 如果尺寸緊凑且重量輕，這樣的開關設備或 二？ /料登錄裝置將是有利的。人們期望該裝置可 靠且不易受不利操作環境條件的影響。人們還期望鍵 盤具有柔性結構。如果開關和鍵盤能節約成本和省電 ’這也是有利的。1320903 IX. DESCRIPTION OF THE INVENTION: TECHNICAL FIELD OF THE INVENTION The present invention relates generally to data logging and switching circuits, and more particularly to switching and matrix switchboards using an electric valley sensing touch panel. [Prior Art] Switches, matrix switch boards, and keypads are very popular in our everyday lives. Example #, the phone (including the > phone, cordless phone, and wireless phone) has a numeric keypad for entering phone numbers and other information or features (such as frequently dialed numbers, contacts, quick dials, etc.). The Personal Digital Assistant (PDA) has a alphanumeric keypad for wheeling commands and information. Even simple electronic devices may have one or more switches for controlling their power, operating modes, and the like. ^ A switch or key in a keyboard or keyboard usually includes a conductor that is in contact with each other; At least the sheet conductor is movable and usually the sheet is in contact with the other, and the upper portion of the conductor sheet that is in contact with the other sheet is usually covered with a compound such as plastic or plastic. The matrix switch board or keyboard can include an array of keys or keys. m n ^ divided into normal and keyboard have? The movable portion 'the movable portion is pressed specifically. The switch (four) spring may be broken at the repeating member. Mechanical switches are also susceptible to adverse environmental conditions that can cause switch failures and wet or machine ===: ', making their electrical and/or poor mechanical switches and keyboards typically bulky and cumbersome. And 6 1320903 mechanical switches and keyboards usually have a rigid or semi-rigid structure. This is not suitable for mechanical switches and keyboards - applications that require features such as small size, light weight, and ease of storage. If the size is compact and lightweight, such a switchgear or two? The material registration device would be advantageous. It is expected that the device will be reliable and not susceptible to adverse operating environmental conditions. It is also desirable for the keyboard to have a flexible structure. It is also advantageous if the switch and keyboard can save cost and save power.
【發明内容】 一種負料登錄裝置（ 300 )，包括多個由介電層下面 的導電板形成的鍵。第一和第二鍵（331，332 ) _的 每個鍵均具有一個連接到相應的電容讀出模組（312 ，314)的導電板（12, 24)。第三鍵（ 333 )具有兩 個導電板，一個導電板（32)連接到第一電容讀出模 組（312)，另一個導電板（34)連接到第二電容讀出 模組（314h當用戶觸摸鍵（331)時，，戶和導電 板（12)j成電容大於參考電容器（123)電容的讀 出電容器（113)。相應的電容讀出模組（312)中的（ 130)生成指示鍵（331)正被觸摸的數位位元信號。 解碼器（301 )將多個電容讀出模組（331，332，333 )的數位位元k號解碼，以相應地生成數位資料信號 7 【實施方式】 :文參照附圖描述本發明的多個實施例，附圖中用 ^同參考數位表利中相似結構或功能的部分。應該注 二附圖的目的僅僅是幫助描述本發明的優S實施例。 匕們的目的不疋無遺漏地描述本發明或對本發明的範 圍加以限制。此外，附圖不一定按比例繪製。 根據本發明’開關電路包括電容讀出電路，該電容 讀出電路檢測用戶是否觸摸開關的鍵或墊片（pad)，然 後相應地將開關導通和斷開。同樣，根據本發明鍵盤電 路匕括個或夕個電谷讀出電路。每一讀出電路均可以 與鍵盤上的一個或多個鍵相連。而且，每一鍵可以與一 個或多個電容讀出電路相連。鍵盤電路還包括連接到電 容讀出電路的數位解碼電路。響應於用戶觸摸鍵盤上的 鍵，解碼電路生成解釋來自電容讀出電路的信號的數位 輸出信號。 圖1是不出根據本發明的電容讀出電路1〇〇的示意 圖。讀出電路100包括時鐘信號發生器1〇2 ◊根據本發 ，，時鐘k號發生器102可以包括任何種類的振盪信 號發生器。例如，可以使用阻容（RC)振盈器、晶體 振盪器等用作時鐘信號發生器102。根據本發明的各 種實施例，時鐘信號的頻率的範圍可以處於幾千赫到 幾兆赫之間。然而，更高或更低的時鐘信號頻率也屬 於本發明的範圍之内。時鐘信號發生器102的時鐘信 號被傳送到讀出電路1〇〇中的開關112和122的控制端 。根據本發明的優選實施例，開關112和122是場效應 電晶體（FET )或雙極型電晶體（B JT )，並且時鐘信 1320903 號被傳送到FET的柵極或BJT的基極。開關112和122分 別與電容器113和123並聯。讀出電路100還包括電流 源111和121。電流源111與開關112和電容器113的並 聯聯結串聯。類似地.，電流源121與開關122和電容器 123的並聯聯結串聯。在本發明的一具體實施例中， 由電流源111和121生成的電流彼此基本相等。當開關 112和122斷開時，電流源111和121分別給電容器113 和123充電。當開關112和122閉合時，來自電流源111 和121的電流旁路過電容器113和123並流向地105。而 且，閉合的開關112和122使電容器113和123放電。 根據本發明，讀出電路1〇〇中的電容器113 (其又被 稱作讀出電容器）讀出與電容讀出電路1〇〇相連的鍵 是否被觸摸。電路示意圖圖1示出讀出電容器113包括 兩個極板114和115。一片導體用作電容器Π3的一個 極板114 (其也稱作讀出極板）◊電容讀出電路1〇〇的 物理結構僅包括電容器113的一個極板114。當用戶觸 摸或按壓與電容讀出電路1〇〇相連的鍵時，用戶的身 體用作電容器113的另一個極板115。圖2示意性示出 與電谷5賣出電路100相連的鍵15〇的剖視圖，並說明讀 出電谷器113的形成。鍵150包括覆蓋在電容器jig的 導電板114之上並與之接觸的介電層116。舉例來說， ^電層116是為開關或鍵盤的外罩、外殼、或外部遮 蓋物的部分。雖然裝置的外殼可以包括各種材料例 如，塑膠、橡膠、金屬等，但是覆蓋讀出電容器極板 114的外殼的部分，也就是圖2所示的層116優選地由 ，緣和電介質材料製成。塑膠是外殼的常用材料，這 是因為它是電介質、不責，並易於製成各種形狀、顏 9 色、硬度。介電層116也可以由柔軟材料製成，使得 鍵150和相關裝置可以折疊或卷成易於存放的緊湊尺 寸圖2示出根據本發明的一實施例，讀出電容器極 板114為平板。這不是為了對本發明的範圍加以限制 。根據本發明，電容器113的讀出電容器極板114可以 具有不同的形狀和大小。另外，極板114可以包括多 片的相互電連接的導體。當用戶觸摸鍵15〇時，用戶 身體的一部分，例如，圖2所示的手指，與覆蓋在讀 出電谷器極板114上的介電層116接觸。如果接觸區域 與覆蓋在極板114上的介電層116重疊，則用戶身體的 該部分用作電容器113的另一個極板ns。用戶身體的 其他部分用作地105 (圖1所示）。 應該注意，當用戶觸摸鍵15〇時，用戶身體起導體 的作用。根據本發明，觸摸鍵150的用戶範圍不局限 於與鍵150直接接觸的用戶身體。它包括與介電層ι16 接觸的任何導電物體’並用作讀出電容器113的極板 115。 回過來參照圖1，電容讀出電路100還包括用於比較 電容器113與123之間電壓差的比較模組130。根據本 發明的一優選實施例，比較模組130包括差動放大器 134。電容器113和123分別連接到差動放大器134的第 —輸入端131和第二輸入端132。差動放大器134的輸 出端135連接到又被稱作集成電容器的電容器138的 第一極板。電容器138的第二極板連接到地1〇5。電容 器138的第一極板還連接到比較器144的第一輸入端 。比較器144的第二輸入端被連接用於接收參考電壓 1320903 143。比較器144的輸出端用作比較模組13〇的輸出端 ’並連接到讀出電路100的輸出端145。 應該注意’比較模組130的結構不局限於上面所述 和圖1所示的結構。根據本發明，比較模組13〇可以是 任何能夠比較輸入端131和132處的電壓脈衝信號並 生成指示哪個電壓脈衝信號更高的輸出信號的電路 元件。 # 在操作中’時鐘信號發生器102以時鐘信號頻率的 速率將開關112和122週期性地導通和斷開。根據本發 明的一優選實施例，開關112和122的導通和斷開狀態 基本相互同步。所以’電容器113和123被週期性地和 基本同時地充電和放電。讀出電容器113的電容回應 於用戶是否觸摸鍵150而變化。另一方面，又被稱作 參考電容器的電容器123的電容基本不變。比較模組 130比較讀出電容器113和參考電容器123的電容，以 確定用戶是否觸摸鍵150以及相應地生成數位信號。 當用戶未觸摸鍵150時，用作讀出電容器113的極板 115的用戶身體遠離極板114。另外，不僅介電層ι16 而且空氣間隙也將極板115與極板114分開。由於空氣 的低介電常數，所以讀出電容器113的電容顯著地小 於參考電容器123的電容。在開關112和122斷開的時 鐘信號階段中，在差動放大器134的輸入端131的電壓 比在輸入端132的電壓上升得快。回應於輸入端131 ( 舉例來说’反相輸入端）處的較南電壓，差動放大器 134在輸出端135生成低電壓。在開關ι12和122閉合的 1320903 時鐘信號階段中，在輸入端131和132的電壓都回到地 電壓電平。所以，差動放大器134在輸出端135生成低 電壓脈衝信號。脈衝的頻率等於電容器Π3和123被充 電和放電的頻率。電容器138對來自差動放大器135的 低電壓脈衝信號進行積分。特別地，在差動放大器134 的輸出端135的低電壓脈衝重複地使電容器138放電 ’從而在比較器144的第一輸入端生成低電壓。比較 器144將在它的第一輸入端的電壓與在它的第二輸入 端的參考電壓143相比較。回應於第一輸入端（舉例 來說，非反相輸入端）處的電壓低於第二輸入端（舉 例來說，反相輸入端）處的參考電壓丨43，比較器144 在電容讀出電路100的輸出端145生成低電壓信號。舉 例來說，低電壓信號的二進位值為〇。 當用戶觸摸鍵150時’作為電流讀出電路的外部 導電物體以及用作讀出電容器113的極板U5的用戶 身體與介電層116接觸。由於極板115向極板114接近 以及介電層116的大介電常數，所以讀出電容器jig的 電容比當用戶未觸摸鍵150時讀出電容器ι13的電容 大得多。根據一優選實施例，讀出電容器i i 3的電容 大於當用戶觸摸鍵150時參考電容器123的電容。在開 關112和122斷開的時鐘信號階段中，在差動放大器 134的輸入端131的電壓比在輸入端132的電壓上升得 慢。回應於輸入端131 (舉例來說，反相輸入端）處 的較低電壓，差動放大器134在輸出端135生成高電壓 。在開關112和122閉合的時鐘信號階段中’在輸入端 131和132的電壓都回到地電壓電平。所以，差動放大 器134在輸出端135生成尚電壓脈衝信號。脈衝的頻率 12 等於電容器113和123被充電和放電的頻率。電容器 138對來自差動放大器134的高電壓脈衝信號進行積 分。特別地，在差動放大器134的輸出端135的高電壓 脈衝重複地對電容器138充電，並在比較器144的第一 輪入端生成高電壓。比較器144將在它的第一輸入端 的電壓與在它的第二輸入端的參考電壓143相比較。 回應於第一輸入端（舉例來說，非反相輸入端）處的 電壓兩於第二輸入端（舉例來說，反相輸入端）處的 參考電壓143’比較器144在讀出電路1〇〇的輸出端145 生成高電壓信號’從而識別出鍵15〇被觸摸。舉例來 說’高電壓信號的二進位值為1。 根據圖1所示的本發明的一具體實施例，輸出端145 連接到開關元件160。在一具體實施例中，開關元件 160包括N溝道場效應電晶體，以及輸出端ι45連接到n 溝道電晶體的柵極》當用戶觸摸鍵15〇時，在柵極的 高電壓信號導通N溝道電晶體。另一方面，當鍵15〇未 被觸摸時’在柵極的低電壓信號斷開N溝道電晶體。 在另一實施例中，輸出端145經由開關元件160中的反 相器連接到N溝道電晶體的栅極。在該實施例中，觸 摸鍵150會斷開N溝道電晶體，而不觸摸鍵15〇會導通N 溝道電晶體。在另一可選實施例中，輸出端145連接 到開關元件160中的p溝道場效應電晶體的栅極。在該 可選實施例中，觸摸鍵15〇將斷開p溝道電晶體，而不 觸摸鍵150將導通P溝道電晶體。在又一可選實施例中 ’輸出端145經由開關元件ι6〇中的反相器連接到p溝 道電晶體的柵極。在該可選實施例中，觸摸鍵15〇將 導通P溝道電晶體，而不觸摸鍵15〇將斷開p溝道電晶 根據本發明的另一且鍊 觸發ΓΠ. f, /、體貫施例，開關元件160包括 餘出媲P)和開關電晶體。觸發器連接在 開關元件1附開關電晶體的柵極之間 μ m破觸摸時’就在輸出端145處生成高電壓 i壓1::尚電壓信號，觸發器改變在其輸出端的 i電平。所以，每當鍵150被 就從斷開狀態改變為導诵壯能切：關電3曰體 斷開狀態。μ導通狀態或從導通狀態改變為 ，容讀出電路刚的性能和功率消耗取決於分別控 ^開關112和122使讀出電容器113和參考電容器123 ，和放電的日夺鐘信號頻率。高頻率通常導致高性能 和南功率消耗。根據本發明的各種實施例，時鐘信號 的頻率範圍處於幾百赫兹到幾㈣之間。纟一優選實 施例中’時鐘信號的頻率大約為幾千赫茲。時鐘信號 發生器102通常包括振盛器，該振盘器可以是簡單的 =容（RC) «器、電壓控制振n電流控制振盘 益、晶體振盪器等。在一優選實施例中，時鐘信號發 生器102包括晶片上的Rc振盪器’這是由於它簡單且 省電。 電容讀出電路100的性能和功率消耗還取決於電流 源111和12卜讀出電容器113和參考電容器123、差動 放大器134、集成電容器138、參考電壓143、和比較 器144的特性。例如，集成電容器138的小電容將使得 充電和放電時間短，這導致讀出電路1〇〇的快速回應 4間。集成電容器138的小電容也導致電容讀出電路 100的較小功率消耗。另外’大電流源111和121將導 致項出電谷益113和參考電容器123的快速充電速率 。根據本發明’電路設計者可以調整電容讀出電路1〇〇 中各種裝置的參數，以獲得期望回應時間和性能。 圖3是示出根據本發明矩陣開關或鍵盤系統的 功能電路示意圖。鍵盤系統3〇〇又被稱作電容傳感鍵 盤（capacitance sensing keyboard)、電容感應小 鍵盤等。鍵盤系統300包括三位元解碼器3〇1，該三位 元解碼器具有三個位資料登錄端302、304、和306， 舉例來說’三個輸入端分別對應於三位二進位資料的 最低有效位、次高有效位、和最高有效位。所以，此 處所述和圖3所示的鍵盤系統3〇〇能夠接收和識別八 個不同值的數位資料，例如，〇、1、2、3、4、5、6 、和7 〇 鍵盤系統300還包括三個電容讀出電路312、314、 和316。根據本發明的優選實施例，三個電容讀出電 路312、314、和316的每個在結構上和功能上類似於 上面參照圖1所述的電容讀出電路1〇〇。讀出電路312 、314和316的輸出端分別連接到解碼器3〇1的位元資 料登錄端302、304、和306。讀出電路312具有讀出信 號輸入端322。同樣，讀出電路314具有讀出信號輸入 端324 ’讀出電路316具有讀出信號輸入端326。在功 月b上’ s賣出k號輸入端322、324、和326相當於圖1所 示的電容讀出電路1〇〇中連接到讀出電容器113的導 電板114和電流源111的節點。 1320903 根據本發明的優選實施例，鍵盤系統300包括小鍵 盤，該小鍵盤由七個資料登錄鍵331、332、333、334 、335、336、和337構成，用於分別輸入數位資料值1 、2、3、4、5、6、和 7 ° 鍵331、332、333、334、335 、336、和337包括類似於上面參照圖2所述的介電層 116的介電層（圖3中未示出）。該介電層可以是覆蓋 整個小鍵盤的整體塑膠層。 鍵331包括導電板12,該導電板位於介電層下面並 連接到讀出電路312的讀出信號輸入端322。所以，觸 摸或按壓鍵331則在解碼器301的最低有效位元資料 登錄端302生成高電壓信號。解碼器301回應於資料登 錄端302處的高電壓信號而生成值為1的數位信號。 鍵332包括導電板24，該導電板位於介電層下面並 連接到讀出電路314的讀出信號輸入端324。所以，觸 摸或按壓鍵332則在解碼器301的次高有效位元資料 登錄端304生成高電壓信號。解碼器301回應於資料登 錄端304處的高電壓信號而生成值為2的數位信號。 鍵3 3 3包括兩個導電板3 2和3 4，运兩個導電板位於 介電層下面。導電板32連接到讀出電路312的讀出信 號輸入端322，以及導電板34連接到讀出電路314的讀 出信號輸入端324。所以，觸摸或按壓鍵333則在解碼 器301的最低有效位元資料登錄端302和次高有效位 元資料登錄端304生成高電壓信號。解碼器3〇1回應於 資料登錄端302和304處的高電壓信號而生成值為3的 數位信號。 16 1320903 鍵334包括導電板46,該導電板位於介電層下面並 連接到讀出電路316的讀出信號輸入端326。所以，觸 摸或按壓鍵334則在解碼器301的最高有效位元資料 登錄端306生成高電壓信號。解碼器301回應於資料登 錄端306處的高電壓信號而生成值為4的數位信號。 鍵335包括兩個導電板52和56，這兩個導電板位於 介電層下面。導電板52連接到讀出電路312的讀出信 號輸入端322，以及導電板56連接到讀出電路316的讀 出信號輸入端326。所以，觸摸或按壓鍵335則在解碼 器301的最低有效位元資料登錄端302和最高有效位 元資料登錄端306生成高電壓信號。解碼器301回應於 資料登錄端302和306處的高電壓信號而生成值為5的 數位信號。 鍵336包括兩個導電板64和66，這兩個導電板位於 介電層下面。導電板64連接到讀出電路314的讀出信 號輸入端324，以及導電板66連接到讀出電路316的讀 出信號輸入端326。所以，觸摸或按壓鍵336則在解碼 器301的次高有效位元資料登錄端304和最高有效位 元資料登錄端306生成高電壓信號。解碼器301回應於 資料登錄端304和306處的高電壓信號而生成值為6的 數位信號。 鍵337包括三個導電板72、74和76，這三個導電板 位於介電層下面。導電板72連接到讀出電路312的讀 出信號輸入端322，導電板74連接到Ί買出電路314的言買 出信號輸入端324，以及導電板76連接到讀出電路316 17 的項出信號輸入端326。所以，觸摸或按壓鍵337則在 解碼is 301的最低有效位元資料登錄端3〇2、次高有效 位元-貝料，錄鳊304、和最高有效位元資料登錄端3〇6 生成兩電壓信號。解碼器3〇1回應於資料登錄端3〇2、 304、和306處的高電壓信號生成值為7的數位信號。 根據本發明的一優選實施例，介電層由將單片塑膠 或橡膠膜覆蓋在鍵盤系統3〇〇的小鍵盤中的所有鍵上 製成。單片膜保護導電板免遭環境中的危險條件例如 潮濕、濺水等的損害。另外，介電層可以由柔軟材料 製成。所以，鍵盤系統3〇〇的小鍵盤可以尺寸緊湊且 重量輕。由於在小鍵盤中沒有可動部件，所以鍵盤系 統300不易受機械故障的影響，所以可靠且耐用。 此處所述的鍵盤系統300包括三位元解碼器3〇1，所 以能夠接收和識別多達八個值的數位資料。結構類似 1鍵盤系統300且包括更高位數位資料解碼器和更多 讀出電路的鍵盤系統能夠識別更多的數位資料值。例 如，具有8位解碼器和八個電容讀出電路的鍵盤系統 能夠識別和區別256個數位資料值^類似地，具有16 位解碼器和16個電容讀出電路的鍵盤系統能夠識別 和區別65, 536個數位資料值。 圖4是示出根據本發明的電話鍵盤或小鍵盤系統 ，功能示意圖。由於電話鍵盤或小鍵盤系統應該 能夠識別十個數位值，小鍵盤系統400包括具有四個 位資料登錄端402、404、406、和408的四位解碼器401 。小鍵盤系統4〇〇還包括分別連接到解碼器4〇1的位元 1320903 資料登錄端402、404 ' 406、和408的四個電容讀出電 路412、414、416和418。根據本發明的一優選實施例 ’四個電容讀出電路412、414、416、和418中的每個 電容讀出電路在結構上和功能上類似於上面參照圖1 所述的電容讀出電路1〇〇。各電容讀出電路412、414 、416、和418均具有相當於圖1所示的電容讀出電路 100中連接到讀出電容器113中的導電板114和電流源 111的卽點的讀出信號輸入端。 四位解碼器401能夠識別多達十六個的數位值，多 於電話小鍵盤所需要的十個資料值。解碼器4〇1的輸 出端連接到音頻發生器445，以生成回應於來自解碼 器401的數位資料信號的電話撥號音。小鍵盤系統400 具有十二個按鈕。十二個按鈕中的十個按鈕對應於打 電話所需的數字值1、2、3、4、5、6、7、8、9、和0 。剩餘的兩個按鈕對應於按鍵式電話機鍵盤上的星號 (*)和井號（#)。圖4示出根據本發明的一具體實 施例的十二個按鈕的電路連接。 小鍵盤系統400還包括類似於上面參照圖2所述的 介電層116的介電層（圖4中未示出）。根據本發明的 一優選實施例，介電層由單片塑膠或橡膠膜完全覆蓋 小鍵盤系統400的上表面而製成。單片臈保護導電板 免遭環境中的危險條件例如潮濕、賤水等的損宝。另 外’介電層可以由柔性材料製成。 按鈕“1”包括一個導電板，該導電板位於介電層 的下面且連接到電容讀出電路412。響應于按叙“ j，，曰 2觸摸或按壓，電容讀出電路412在解碼器401的位元 資料登錄端402生成高電壓信號。解碼器4〇1生成對應 於二進位資料值〇〇〇1的解碼數位信號。音頻發生器 445接收和處理解碼數位信號〇〇〇1以及在電話系統中 生成對應於“1”的撥號音。 按鈕2包括一個導電板，該導電板位於介電層 的下面且連接到電容讀出電路414。響應于按鈕“2” f觸摸或按壓’電容讀出電路414在解碼器4〇1的位元 k料登錄端404生成高電壓信號。解碼器4〇1生成對應 於二進位資料值0010的解碼數位信號。音頻發生= 445接收和處理解碼數位信號〇〇1〇以及在電話系統中 生成對應於“2”的撥號音。 按紐3包括兩個導電板，這兩個導電板位於介 電層的下面且連接到電容讀出電路412和414。響應于 按鈕“3”被觸摸或按壓，電容讀出電路412和414分 別在解碼器401的位元資料登錄端4〇2和4〇4生成高電 壓信號。解碼器401生成對應於二進位資料值〇〇11的 解碼數位信號。音頻發生器445接收和處理解碼數位 k號0011以及在電話系統中生成對應於“3，，的撥號 音。 按鈕4包括一個導電板，該導電板位於介電層 的下面且連接到電容讀出電路416。響應 被觸摸或按壓’電容讀出電路416在解碼器4G1的位元 貧料登錄端406生成高電壓信號。解碼器4〇1生成對應 於二進位資料值0100的解碼數位信號。音頻發生器 20 445接收和處理解碼數位信號0100以及在電話系統中 生成對應於“4”的撥號音。 按鈕5”包括兩個導電板，這兩個導電板位於介 電層的下面且連接到電容讀出電路412和416。響應于 按鈕“5”被觸摸或按壓，電容讀出電路412和416分 別在解碼器401的位元資料登錄端402和406生成高電 壓信號。解碼器401生成對應於二進位資料值〇1〇\的 f碼數位信號。音頻發生器445接收和處理解碼數位 信號0101以及在電話系統中生成對應於“ 5，，的撥號 音。 按鈕6”包括兩個導電板，該兩個導電板位於介 電層的下面且連接到電容讀出電路414和416。響應于 按鈕“6”被觸摸或按壓，電容讀出電路414和416分 別在解碼器401的位元資料登錄端4〇4和4〇6生成高電 壓信號。解碼器401生成對應於二進位資料值〇11°〇的 f碼數位信號。音頻發生器445接收和處理解碼數位 L號0110以及在電話系統中生成對應於“ 6，，的撥號 音。 按鈕Ί包括兩個導電板，這兩個導電板位於介 電層的下面且連接到電容讀出電路416和418。響應于 按鈕1被觸摸或按壓，電容讀出電路416和418分 別在解碼器401的位元資料登錄端4〇6和4〇8生成高電 ，信號。解碼謂！生成對應H位請值·的 解碼數位信號。音頻發生器445接收和處理解碼數位 k號1100以及在電話系統中生成對應於“ ？，，的撥號 21 1320903 音。 按鈕8包括一個導電板，該導電板位於介電層 的下面且連接到電容讀出電路418。響應于按鈕“8” 被觸摸或按壓，電容讀出電路418在解碼器4〇1的位元 資料登錄端408生成高電壓信號。解碼器4〇1生成對應 於二進位資料值1 〇〇〇的解碼數位信號。音頻發生器 445接收和處理解碼數位信號1〇〇〇以及在電話系统; 生成對應於“8”的撥號音。 ，按紐9包括兩個導電板，該兩個導電板位於介 電層的下面且連接到電容讀出電路412和418。響應于 按鈕“9”被觸摸或按壓，電容讀出電路412和418分 別在解碼器401的位元資料登錄端4〇2和4〇8生成高電 壓信號。解碼器401生成對應於二進位資料值薩的 解碼數位信號。音頻發生器445接收和處理解碼數位 k號1001以及在電話系統中生成對應於“9”的撥號 按鈕“〇，，包括兩個導電板’ $兩個導電板位於介 電層的下面且連接到電容讀出電路414和418。變應于 按紐被觸摸或按壓，t容讀出電路414和曰41‘8分 =解碼H4G1的位元資料登錄端4〇4和權生成高電 η。解碼器4〇1生成對應於二進位資料值1〇1〇的 信號⑻。以及在電” 處理解碼數位 仕电活糸統中生成對應於“〇，，的撥號 22 1320903 按紐*包括二個導電板，這三個導電板位於介 電層的下面且連接到電容讀出電路412、414、和418 。響應于按鈕被觸摸或按壓，電容讀出電路412 、414、和418分別在解碼器4〇1的位元資料登錄端4〇2 404、和408生成兩電壓信號。解碼器4〇1生成對應 於二進位資料值ι〇11的解碼數位信號。音頻發生ς 445接收和處理解碼數位信號1〇11以及在電話系統中 生成對應於的撥號音。 按鈕#”包括三個導電板，該三個導電板位於介 電層的下面且連接到電容讀出電路414、416和418。 響應于按鈕“#”被觸摸或按壓，電容讀出電路414、 416和418分別在解碼器4〇1的位元資料登錄端4〇4、 406和408生成高電壓信號。解碼器4〇1生成對應於二 進位資料值liio的解碼數位信號。音頻發生器445接 收和處理解碼數位信號丨丨1〇以及在電話系統中生 對應於“#”的撥號音。 應該明白，電話小鍵盤的連接不局限於上面參照圖 4所述的内谷。解碼器也不局限於是四位解碼器。 例如，根攄本發明的可選實施例，電話小鍵盤系統可 以包括連接到五個電容讀出電路的五位元解碼器。在 该實施例中，與每一按鈕相關聯的導電板的數量可以 局限於一個或兩_ ’如果想要一個小而高度敏感的小 鍵盤系統，這個數量可能是有利的。 到現在應該理解已提供了電容觸摸板資料登錄、矩 陣開關電路 '和鍵盤系統。根據本發明，鍵盤系統回 23 1320903 應用戶觸摸鍵盤系統中的鍵或按鈕而生 。鍵或按紐可以包括-個或多個導電板，每個導= 連接到相應的電容讀出電路。數位資料解碼器將 讀出電路的輪出解碼。這種矩陣開關佈置使少量的； 容讀出電路能夠支援鍵盤系統中的很多的鍵，從 化了 $路以及提高了系統的成本經濟性和功率效率 。通常，根據本發明，具有1^個電容讀出電路的鍵盤 系統可以支援多達穴個鍵，其中N是整數。 根據本發明的矩陣開關或鍵盤系統不必有可動部 件’所，可靠和耐用。另外，系統可以包含在不漏水 或不透氣的電介質外層中，以提供保護免遭不利操作 ί哀境條件的損害。而且，根據本發明的開關和鍵盤系 統可以尺寸緊凑、重量輕和具有柔性結構。而且，它 們是節約成本和省電的。根據本發明的小鍵盤系統可 以用於各種需要資料和/或命令輸入的應用，例如電 腦鍵盤、PDA、計算n、移動電話、設備遠端控制等 。例如，PDA可以具有根據本發明的柔性字母數位小 鍵盤。小鍵盤在展開時具有相對較大的區域，使得可 以容易地使用字母數位小鍵盤上的每一個鍵。當不使 用時，柔性小鍵盤可以折疊或卷成易於存放的緊凑尺 寸。 雖然上面已描述本發明的特定實施例，但是它們的 目的不是對本發明的範圍加以限制。本發明包括那些 對本領域技術人員來說是顯而易見的對所述實施例 的更改和變化。例如，根據本發明的開關系統可以包 括通過在用戶不觸摸裝置時斷開該裝置來控制該裝 24 丄wuyuj 置的功率消耗的單個電流讀出電路。 【圖式簡單說明】 圖1是示出根據本發明的電容讀出電路的示意圖； 圖2是根據本發明的觸摸板鍵的剖視示意圖； # 圖3是示出根據本發明的矩陣開關或鍵盤系統的功 能示意圖；以及 圖4是示出根據本發明的電話鍵盤或小鍵盤系統的 功能不意圖。 【主要元件符號說明】 φ 12、24 、32、34、46............導電板 52、56、66、64、72、74、76…導電板 100 ............電路 102 ............時鐘信號發生器 105 ............地 111、121 ............電流源 112 ' 122 ............開關 113 ' 123 ............電容器 25 1320903 114 ' 115 ............極板 116 ............介電層 130 ............比較模組 131 ............第一輸入端 132 ............第二輸入端 134 ............差動放大器 135 ............輸出端 138 ............電容器 143 ............參考電壓SUMMARY OF THE INVENTION A negative material registration device (300) includes a plurality of keys formed by conductive plates under the dielectric layer. Each of the first and second keys (331, 332) has a conductive plate (12, 24) connected to a corresponding capacitive readout module (312, 314). The third button (333) has two conductive plates, one conductive plate (32) is connected to the first capacitive readout module (312), and the other conductive plate (34) is connected to the second capacitive readout module (314h). When the user touches the key (331), the household and the conductive plate (12) j form a read capacitor (113) whose capacitance is larger than the capacitance of the reference capacitor (123). (130) generation in the corresponding capacitance readout module (312) The indicator bit (331) is being touched by the digit bit signal. The decoder (301) decodes the digit bit k of the plurality of capacitance readout modules (331, 332, 333) to generate the digital data signal 7 accordingly. [Embodiment] The embodiments of the present invention are described with reference to the accompanying drawings, in which reference to The invention is not intended to limit the scope of the invention, and the drawings are not necessarily drawn to scale. In accordance with the invention, a switching circuit includes a capacitor readout circuit that reads Out circuit detects whether the user touches the switch a key or a pad, and then the switch is turned on and off accordingly. Also, the keyboard circuit according to the present invention includes one or a solar valley readout circuit. Each readout circuit can be associated with one of the keyboards. Or a plurality of keys are connected. Moreover, each key can be connected to one or more capacitor readout circuits. The keyboard circuit further includes a digital bit decoding circuit connected to the capacitance readout circuit. The decoding circuit generates in response to the user touching a key on the keyboard. The digital output signal of the signal from the capacitance readout circuit is explained. Fig. 1 is a schematic diagram of the capacitance readout circuit 1A according to the present invention. The readout circuit 100 includes a clock signal generator 1〇2, according to the present invention, The clock k generator 102 can include any type of oscillating signal generator. For example, a RC resonator, a crystal oscillator, or the like can be used as the clock signal generator 102. According to various embodiments of the present invention, the clock The frequency of the signal can range from a few kilohertz to a few megahertz. However, higher or lower clock signal frequencies are also within the scope of the present invention. The clock signal of the generator 102 is transmitted to the control terminals of the switches 112 and 122 in the readout circuit 1A. According to a preferred embodiment of the invention, the switches 112 and 122 are field effect transistors (FETs) or bipolar types. Crystal (B JT ), and clock signal 1320903 is transferred to the gate of the FET or the base of BJT. Switches 112 and 122 are connected in parallel with capacitors 113 and 123, respectively. Readout circuit 100 also includes current sources 111 and 121. Current source 111 is coupled in series with the parallel connection of switch 112 and capacitor 113. Similarly, current source 121 is coupled in series with the parallel connection of switch 122 and capacitor 123. In one embodiment of the invention, the currents generated by current sources 111 and 121 are mutually coupled. Basically equal. When switches 112 and 122 are open, current sources 111 and 121 charge capacitors 113 and 123, respectively. When switches 112 and 122 are closed, current from current sources 111 and 121 bypasses capacitors 113 and 123 and flows to ground 105. Moreover, the closed switches 112 and 122 discharge the capacitors 113 and 123. According to the present invention, the capacitor 113 in the readout circuit 1 (which is also referred to as a read capacitor) senses whether or not the key connected to the capacitance readout circuit 1 is touched. Circuit Schematic FIG. 1 shows that the read capacitor 113 includes two plates 114 and 115. A piece of conductor is used as a plate 114 of the capacitor Π3 (also referred to as a readout plate). The physical structure of the tantalum capacitor readout circuit 1A includes only one plate 114 of the capacitor 113. When the user touches or presses a key connected to the capacitance sensing circuit 1A, the user's body functions as the other plate 115 of the capacitor 113. Fig. 2 is a schematic cross-sectional view showing the key 15A connected to the electric valley 5 selling circuit 100, and illustrates the formation of the readout electric grid 113. The key 150 includes a dielectric layer 116 overlying and in contact with the conductive plate 114 of the capacitor jig. For example, electrical layer 116 is part of a housing, housing, or exterior covering of a switch or keyboard. While the outer casing of the device may comprise various materials such as plastic, rubber, metal, etc., the portion of the outer casing that covers the readout capacitor plate 114, that is, the layer 116 shown in Figure 2, is preferably made of a rim and a dielectric material. Plastic is a commonly used material for the outer casing because it is a dielectric, it is not responsible, and it is easy to make various shapes, colors, and hardness. The dielectric layer 116 can also be made of a soft material such that the keys 150 and associated devices can be folded or rolled into a compact size that is easy to store. Figure 2 illustrates the sense capacitor plate 114 as a flat plate in accordance with an embodiment of the present invention. This is not intended to limit the scope of the invention. In accordance with the present invention, the sense capacitor plates 114 of capacitor 113 can have different shapes and sizes. Additionally, the plate 114 can include a plurality of conductors that are electrically connected to each other. When the user touches the key 15 ,, a portion of the user's body, such as the finger shown in FIG. 2, is in contact with the dielectric layer 116 overlying the readout grid plate 114. If the contact area overlaps with the dielectric layer 116 overlying the plate 114, this portion of the user's body acts as the other plate ns of the capacitor 113. The other part of the user's body is used as ground 105 (shown in Figure 1). It should be noted that when the user touches the key 15 ,, the user's body functions as a conductor. According to the present invention, the user range of the touch key 150 is not limited to the user's body in direct contact with the key 150. It includes any conductive object ' in contact with the dielectric layer ι16' and serves as a plate 115 for the readout capacitor 113. Referring back to Figure 1, the capacitor readout circuit 100 further includes a comparison module 130 for comparing the voltage difference between the capacitors 113 and 123. In accordance with a preferred embodiment of the present invention, the comparison module 130 includes a differential amplifier 134. Capacitors 113 and 123 are connected to a first input terminal 131 and a second input terminal 132 of the differential amplifier 134, respectively. The output 135 of the differential amplifier 134 is coupled to a first plate of a capacitor 138, also referred to as an integrated capacitor. The second plate of capacitor 138 is connected to ground 1〇5. The first plate of capacitor 138 is also coupled to the first input of comparator 144. A second input of comparator 144 is coupled for receiving a reference voltage 1320903 143. The output of the comparator 144 is used as the output terminal of the comparison module 13A and is connected to the output terminal 145 of the readout circuit 100. It should be noted that the structure of the comparison module 130 is not limited to the structure described above and shown in Fig. 1. In accordance with the present invention, the comparison module 13A can be any circuit component capable of comparing the voltage pulse signals at the inputs 131 and 132 and generating an output signal indicating which voltage pulse signal is higher. In operation, the clock signal generator 102 periodically turns the switches 112 and 122 on and off at a rate of the clock signal frequency. In accordance with a preferred embodiment of the present invention, the on and off states of switches 112 and 122 are substantially synchronized with one another. Therefore, the capacitors 113 and 123 are charged and discharged periodically and substantially simultaneously. The capacitance of the read capacitor 113 changes in response to whether the user touches the key 150. On the other hand, the capacitance of the capacitor 123, which is also referred to as a reference capacitor, is substantially unchanged. The comparison module 130 compares the capacitances of the read capacitor 113 and the reference capacitor 123 to determine whether the user touches the key 150 and generates a digital signal accordingly. When the user does not touch the key 150, the user's body serving as the plate 115 of the readout capacitor 113 is away from the plate 114. In addition, not only the dielectric layer ι16 but also the air gap also separates the plate 115 from the plate 114. Due to the low dielectric constant of air, the capacitance of the read capacitor 113 is significantly smaller than the capacitance of the reference capacitor 123. In the clock signal phase at which switches 112 and 122 are open, the voltage at input 131 of differential amplifier 134 rises faster than the voltage at input 132. In response to the souther voltage at input 131 (e.g., the 'inverting input'), differential amplifier 134 generates a low voltage at output 135. In the 1320903 clock signal phase where switches ι12 and 122 are closed, the voltages at inputs 131 and 132 both return to ground voltage levels. Therefore, the differential amplifier 134 generates a low voltage pulse signal at the output terminal 135. The frequency of the pulses is equal to the frequency at which capacitors Π3 and 123 are charged and discharged. The capacitor 138 integrates the low voltage pulse signal from the differential amplifier 135. In particular, the low voltage pulse at the output 135 of the differential amplifier 134 repeatedly discharges capacitor 138' to generate a low voltage at the first input of comparator 144. Comparator 144 compares the voltage at its first input to the reference voltage 143 at its second input. In response to the voltage at the first input (for example, the non-inverting input) being lower than the reference voltage 丨43 at the second input (for example, the inverting input), the comparator 144 is reading at the capacitor Output 145 of circuit 100 generates a low voltage signal. For example, the binary value of the low voltage signal is 〇. When the user touches the key 150, the external conductive object as the current readout circuit and the user's body serving as the plate U5 of the readout capacitor 113 are in contact with the dielectric layer 116. Since the plate 115 approaches the plate 114 and the large dielectric constant of the dielectric layer 116, the capacitance of the read capacitor jig is much larger than the capacitance of the read capacitor ι13 when the user does not touch the key 150. According to a preferred embodiment, the capacitance of the sense capacitor i i 3 is greater than the capacitance of the reference capacitor 123 when the user touches the key 150. In the clock signal phase in which switches 112 and 122 are open, the voltage at input 131 of differential amplifier 134 rises more slowly than the voltage at input 132. In response to the lower voltage at input 131 (e.g., the inverting input), differential amplifier 134 generates a high voltage at output 135. In the phase of the clock signal at which switches 112 and 122 are closed, the voltages at input terminals 131 and 132 return to the ground voltage level. Therefore, differential amplifier 134 generates a still voltage pulse signal at output 135. The frequency of the pulse 12 is equal to the frequency at which the capacitors 113 and 123 are charged and discharged. The capacitor 138 integrates the high voltage pulse signal from the differential amplifier 134. In particular, the high voltage pulse at the output 135 of the differential amplifier 134 repeatedly charges the capacitor 138 and generates a high voltage at the first wheel-in end of the comparator 144. Comparator 144 compares the voltage at its first input to the reference voltage 143 at its second input. Responding to the voltage at the first input (for example, the non-inverting input) is two at the second input (for example, the inverting input), the reference voltage 143' comparator 144 is in the readout circuit 1 The output 145 of the chirp generates a high voltage signal 'to identify that the key 15 is touched. For example, the high-voltage signal has a binary value of 1. According to a particular embodiment of the invention illustrated in Figure 1, the output 145 is coupled to the switching element 160. In one embodiment, the switching element 160 includes an N-channel field effect transistor, and the output terminal ι45 is coupled to the gate of the n-channel transistor. When the user touches the key 15 ,, the high voltage signal at the gate is turned on. Channel transistor. On the other hand, when the key 15 is not touched, the low voltage signal at the gate turns off the N-channel transistor. In another embodiment, output 145 is coupled to the gate of the N-channel transistor via a phase inverter in switching element 160. In this embodiment, the touch key 150 turns off the N-channel transistor, while the touch key 15 turns on the N-channel transistor. In another alternative embodiment, output 145 is coupled to the gate of a p-channel field effect transistor in switching element 160. In this alternative embodiment, the touch key 15 will turn off the p-channel transistor, while the touch key 150 will turn on the P-channel transistor. In yet another alternative embodiment, the output 145 is coupled to the gate of the p-channel transistor via an inverter in the switching element ι6〇. In this alternative embodiment, the touch key 15 turns on the P-channel transistor, and the touch-free key 15 turns off the p-channel transistor. According to the present invention, another chain trigger ΓΠ. f, /, body By way of example, switching element 160 includes a residual 媲P) and a switching transistor. When the flip-flop is connected between the gate of the switching element 1 and the switching transistor, the μ m breaks the touch, and a high voltage is generated at the output terminal 145. The voltage is also a voltage signal, and the flip-flop changes the i level at its output. . Therefore, whenever the key 150 is changed from the off state to the guide, the switch can be turned off: the power off state is turned off. The μ conduction state or the change from the conduction state to the capacity and power consumption of the readout circuit depends on the control of the switches 112 and 122, respectively, the read capacitor 113 and the reference capacitor 123, and the frequency of the day-to-day signal of the discharge. High frequencies often result in high performance and south power consumption. According to various embodiments of the invention, the frequency range of the clock signal is between a few hundred hertz and a few (four). In a preferred embodiment, the frequency of the 'clock signal is approximately a few kilohertz. The clock signal generator 102 typically includes a vibrator that can be simple = capacitance (RC) «, voltage controlled oscillator n current controlled oscillator, crystal oscillator, and the like. In a preferred embodiment, clock signal generator 102 includes an Rc oscillator on the wafer' because it is simple and power efficient. The performance and power consumption of the capacitance sensing circuit 100 also depends on the characteristics of the current sources 111 and 12, the read capacitor 113 and the reference capacitor 123, the differential amplifier 134, the integrated capacitor 138, the reference voltage 143, and the comparator 144. For example, the small capacitance of the integrated capacitor 138 will result in a short charge and discharge time, which results in a fast response of the readout circuit 1 . The small capacitance of the integrated capacitor 138 also results in less power consumption of the capacitive readout circuit 100. In addition, the 'high current sources 111 and 121 will cause the fast charge rate of the power generation grid 113 and the reference capacitor 123. According to the present invention, the circuit designer can adjust the parameters of the various devices in the capacitance readout circuit 1 to obtain the desired response time and performance. Figure 3 is a schematic diagram showing the functional circuit of a matrix switch or keyboard system in accordance with the present invention. The keyboard system 3 is also referred to as a capacitance sensing keyboard, a capacitive sensing keypad, and the like. The keyboard system 300 includes a three-bit decoder 3.1, which has three bit data registers 302, 304, and 306. For example, 'the three inputs correspond to the lowest of the three-bit binary data, respectively. Valid bit, second most significant bit, and most significant bit. Therefore, the keyboard system 3 described herein and shown in FIG. 3 is capable of receiving and recognizing eight different values of digital data, for example, 〇, 1, 2, 3, 4, 5, 6, and 7 〇 keyboard systems. 300 also includes three capacitive readout circuits 312, 314, and 316. In accordance with a preferred embodiment of the present invention, each of the three capacitive readout circuits 312, 314, and 316 is structurally and functionally similar to the capacitive readout circuit 1 described above with reference to FIG. The outputs of the readout circuits 312, 314 and 316 are connected to the bit data registration terminals 302, 304, and 306 of the decoder 3.1, respectively. Readout circuit 312 has a read signal input 322. Similarly, readout circuitry 314 has sense signal input 324'. Readout circuitry 316 has sense signal input 326. The 's sold k-number inputs 322, 324, and 326 on the power month b correspond to the nodes of the capacitor readout circuit 1 shown in FIG. 1 connected to the conductive plate 114 and the current source 111 of the read capacitor 113. . 1320903 In accordance with a preferred embodiment of the present invention, keyboard system 300 includes a keypad that is comprised of seven data entry keys 331, 332, 333, 334, 335, 336, and 337 for respectively inputting a digital data value of 1, The 2, 3, 4, 5, 6, and 7 ° keys 331, 332, 333, 334, 335, 336, and 337 comprise a dielectric layer similar to the dielectric layer 116 described above with respect to FIG. 2 (in FIG. 3 Not shown). The dielectric layer can be an integral plastic layer covering the entire keypad. Key 331 includes a conductive plate 12 that is positioned below the dielectric layer and that is coupled to sense signal input 322 of readout circuitry 312. Therefore, the touch or press key 331 generates a high voltage signal at the least significant bit data registration end 302 of the decoder 301. The decoder 301 generates a digital signal having a value of one in response to the high voltage signal at the data register terminal 302. The key 332 includes a conductive plate 24 that is positioned below the dielectric layer and that is coupled to the sense signal input 324 of the readout circuit 314. Therefore, the touch or press key 332 generates a high voltage signal at the next most significant bit data register end 304 of the decoder 301. The decoder 301 generates a digital signal having a value of 2 in response to the high voltage signal at the data register terminal 304. The key 3 3 3 includes two conductive plates 3 2 and 3 4 which are placed under the dielectric layer. Conductive plate 32 is coupled to read signal input 322 of readout circuit 312, and conductive plate 34 is coupled to read signal input 324 of readout circuit 314. Therefore, the touch or press key 333 generates a high voltage signal at the least significant bit data registration end 302 and the next most significant bit data registration end 304 of the decoder 301. The decoder 311 generates a digital signal having a value of 3 in response to the high voltage signal at the data register terminals 302 and 304. The 16 1320903 key 334 includes a conductive plate 46 that is positioned below the dielectric layer and that is coupled to the sense signal input 326 of the readout circuit 316. Therefore, the touch or press key 334 generates a high voltage signal at the most significant bit data entry end 306 of the decoder 301. The decoder 301 generates a digital signal having a value of 4 in response to the high voltage signal at the data register 306. The key 335 includes two conductive plates 52 and 56 which are located below the dielectric layer. Conductive plate 52 is coupled to read signal input 322 of readout circuit 312, and conductive plate 56 is coupled to read signal input 326 of readout circuit 316. Therefore, the touch or press key 335 generates a high voltage signal at the least significant bit data registration end 302 and the most significant bit data registration end 306 of the decoder 301. The decoder 301 generates a digital signal having a value of 5 in response to the high voltage signal at the data registration terminals 302 and 306. Key 336 includes two conductive plates 64 and 66 that are positioned below the dielectric layer. Conductive plate 64 is coupled to read signal input 324 of readout circuit 314, and conductive plate 66 is coupled to read signal input 326 of readout circuit 316. Therefore, the touch or press key 336 generates a high voltage signal at the next most significant bit data registration end 304 and the most significant bit data registration end 306 of the decoder 301. The decoder 301 generates a digital signal having a value of 6 in response to the high voltage signal at the data register terminals 304 and 306. The key 337 includes three conductive plates 72, 74 and 76 which are located below the dielectric layer. The conductive plate 72 is connected to the read signal input terminal 322 of the readout circuit 312, the conductive plate 74 is connected to the buy signal input terminal 324 of the buyout circuit 314, and the conductive plate 76 is connected to the readout circuit 316. Signal input 326. Therefore, the touch or press key 337 generates two of the least significant bit data registration end 3, 2, the second most significant bit-before, the recording 304, and the most significant bit data registration end 3〇6 of the is 301. Voltage signal. The decoder 311 generates a digital signal having a value of 7 in response to the high voltage signal at the data register terminals 3, 2, 304, and 306. In accordance with a preferred embodiment of the present invention, the dielectric layer is formed from all of the keys that are overlaid in a keypad of the keyboard system 3's with a single piece of plastic or rubber film. The monolithic film protects the conductive plates from dangerous conditions in the environment such as moisture, splashing water, and the like. Alternatively, the dielectric layer can be made of a soft material. Therefore, the keypad of the keyboard system can be compact and lightweight. Since there is no movable part in the keypad, the keyboard system 300 is not susceptible to mechanical failure, so it is reliable and durable. The keyboard system 300 described herein includes a three-bit decoder 3.1 that is capable of receiving and identifying digital data of up to eight values. A keyboard system similar in structure to the keyboard system 300 and including a higher bit data decoder and more readout circuits is capable of recognizing more digital data values. For example, a keyboard system with an 8-bit decoder and eight capacitive readout circuits can identify and distinguish 256 digital data values. Similarly, a keyboard system with a 16-bit decoder and 16 capacitive readout circuits can recognize and distinguish 65 , 536 digit data values. 4 is a functional diagram showing a telephone keypad or keypad system in accordance with the present invention. Since the telephone keypad or keypad system should be able to recognize ten digit values, the keypad system 400 includes a four-bit decoder 401 having four bit data registers 402, 404, 406, and 408. The keypad system 4〇〇 also includes four capacitive readout circuits 412, 414, 416 and 418 connected to the bit 1320903 data register terminals 402, 404 '406, and 408 of the decoder 4〇1, respectively. According to a preferred embodiment of the present invention, each of the four capacitor readout circuits 412, 414, 416, and 418 is structurally and functionally similar to the capacitor readout circuit described above with reference to FIG. 1〇〇. Each of the capacitance readout circuits 412, 414, 416, and 418 has a readout signal corresponding to a defect point of the conductive plate 114 and the current source 111 connected to the readout capacitor 113 in the capacitance readout circuit 100 shown in FIG. Input. The four-bit decoder 401 is capable of recognizing up to sixteen digit values, which is more than ten data values required by the telephone keypad. The output of decoder 401 is coupled to tone generator 445 to generate a telephone dial tone responsive to the digital data signal from decoder 401. The keypad system 400 has twelve buttons. Ten of the twelve buttons correspond to the numerical values 1, 2, 3, 4, 5, 6, 7, 8, 9, and 0 required to make a call. The remaining two buttons correspond to the asterisk (*) and pound sign (#) on the touch-tone phone keypad. Figure 4 illustrates the circuit connections of twelve buttons in accordance with an embodiment of the present invention. The keypad system 400 also includes a dielectric layer (not shown in Figure 4) similar to the dielectric layer 116 described above with respect to Figure 2. In accordance with a preferred embodiment of the present invention, the dielectric layer is formed from a single piece of plastic or rubber film that completely covers the upper surface of the keypad system 400. The monolithic crucible protects the conductive plate from dangerous conditions such as moisture and drowning in the environment. Alternatively, the dielectric layer can be made of a flexible material. Button "1" includes a conductive plate that is positioned below the dielectric layer and that is coupled to capacitor readout circuitry 412. In response to the "j, 曰2 touch or press, the capacitance readout circuit 412 generates a high voltage signal at the bit data registration end 402 of the decoder 401. The decoder 4〇1 generates a value corresponding to the binary data. The decoded digital signal of 1. The audio generator 445 receives and processes the decoded digital signal 〇〇〇1 and generates a dial tone corresponding to "1" in the telephone system. The button 2 includes a conductive plate located at the dielectric layer. Next, and connected to the capacitor readout circuit 414. In response to the button "2" f touch or press the 'capacitance readout circuit 414 generates a high voltage signal at the bit register 404 of the decoder 4〇1. Decoder 4〇1 A decoded digital signal corresponding to the binary data value 0010 is generated. Audio generation = 445 receives and processes the decoded digital signal 〇〇 1 〇 and generates a dial tone corresponding to "2" in the telephone system. Button 3 includes two conductive plates The two conductive plates are located below the dielectric layer and are connected to the capacitance readout circuits 412 and 414. In response to the button "3" being touched or pressed, the capacitance readout circuits 412 and 414 are respectively located at the bit of the decoder 401. The high voltage signals are generated by the login terminals 4〇2 and 4〇4. The decoder 401 generates a decoded digit signal corresponding to the binary data value 〇〇 11. The audio generator 445 receives and processes the decoded digit k number 0011 and generates it in the telephone system. Corresponds to the dial tone of "3,". Button 4 includes a conductive plate that is positioned below the dielectric layer and that is coupled to capacitor readout circuitry 416. The response is touched or pressed by the 'capacitance readout circuit 416 to generate a high voltage signal at the bit lean register 406 of the decoder 4G1. The decoder 4〇1 generates a decoded digit signal corresponding to the binary data value 0100. The tone generator 20 445 receives and processes the decoded digital signal 0100 and generates a dial tone corresponding to "4" in the telephone system. The button 5" includes two conductive plates that are located below the dielectric layer and that are connected to the capacitive readout circuits 412 and 416. In response to the button "5" being touched or pressed, the capacitive readout circuits 412 and 416 are respectively A high voltage signal is generated at the bit data registration ends 402 and 406 of the decoder 401. The decoder 401 generates an f code digital signal corresponding to the binary data value 〇 1 〇 \. The audio generator 445 receives and processes the decoded digital signal 0101 and A dial tone corresponding to "5," is generated in the telephone system. The button 6" includes two conductive plates that are located below the dielectric layer and that are connected to the capacitive readout circuits 414 and 416. In response to the button "6" being touched or pressed, the capacitive readout circuits 414 and 416 are respectively A high voltage signal is generated at the bit material registration terminals 4〇4 and 4〇6 of the decoder 401. The decoder 401 generates an f code digital signal corresponding to the binary data value 〇11°〇. The audio generator 445 receives and processes the decoding. The digital L number 0110 and the dial tone corresponding to "6," are generated in the telephone system. The button Ί includes two conductive plates that are positioned below the dielectric layer and connected to capacitive readout circuits 416 and 418. In response to the button 1 being touched or pressed, the capacitance readout circuits 416 and 418 generate a high power signal at the bit material registration terminals 4〇6 and 4〇8 of the decoder 401, respectively. Decoding! A decoded digital signal corresponding to the H bit value is generated. The tone generator 445 receives and processes the decoded digit k number 1100 and generates a dial 21 1320903 tone corresponding to "?," in the telephone system. The button 8 includes a conductive plate located below the dielectric layer and connected to the capacitor The readout circuit 418. In response to the button "8" being touched or pressed, the capacitance readout circuit 418 generates a high voltage signal at the bit data registration end 408 of the decoder 4〇1. The decoder 4〇1 generates a data corresponding to the binary data. A decoded digital signal of value 1. The audio generator 445 receives and processes the decoded digital signal 1 〇〇〇 and in the telephone system; generates a dial tone corresponding to "8". The button 9 includes two conductive plates, Two conductive plates are located underneath the dielectric layer and are connected to capacitive readout circuits 412 and 418. Capacitive readout circuits 412 and 418 are respectively located at the bit data register side of decoder 401 in response to button "9" being touched or pressed. The high voltage signal is generated by 4〇2 and 4〇8. The decoder 401 generates a decoded digital signal corresponding to the binary data value. The audio generator 445 receives and processes the decoded digit k number 1001 and in the telephone system. A dial button corresponding to "9" is generated, "〇, including two conductive plates". Two conductive plates are located under the dielectric layer and connected to the capacitance readout circuits 414 and 418. When the button is touched or pressed, the t-readout circuit 414 and 曰41 '8 points = the bit data registration terminal 4〇4 of the decoding H4G1 and the weight generating high voltage η. The decoder 4〇1 generates a signal (8) corresponding to the binary data value 1〇1〇. And in the electric processing and decoding digital electric system, the corresponding dialing 22 1320903 button* is included in the electric circuit to include two conductive plates, which are located under the dielectric layer and connected to the capacitor readout Circuits 412, 414, and 418. In response to the button being touched or pressed, the capacitance readout circuits 412, 414, and 418 generate two voltage signals at the bit material registration terminals 4〇2, 404, and 408 of the decoder 4〇1, respectively. The decoder 4〇1 generates a decoded digit signal corresponding to the binary data value ι〇11. The audio generation 445 receives and processes the decoded digital signal 1〇11 and generates a corresponding dial tone in the telephone system. The button #" includes three conductive plates that are located below the dielectric layer and that are connected to the capacitive readout circuits 414, 416, and 418. In response to the button "#" being touched or pressed, the capacitance readout circuit 414, 416 and 418 respectively generate a high voltage signal at the bit material registration terminals 4〇4, 406 and 408 of the decoder 4〇1. The decoder 4〇1 generates a decoded digit signal corresponding to the binary data value liio. Receiving and processing the decoded digital signal 丨丨1〇 and generating a dial tone corresponding to “#” in the telephone system. It should be understood that the connection of the telephone keypad is not limited to the inner valley described above with reference to Fig. 4. The decoder is also not Limited to a four-bit decoder. For example, in accordance with an alternative embodiment of the present invention, a telephone keypad system can include a five-bit decoder coupled to five capacitive readout circuits. In this embodiment, with each button The number of associated conductive plates can be limited to one or two. 'If you want a small, highly sensitive keypad system, this number can be advantageous. It should be understood now that a capacitive touchpad has been provided. Material registration, matrix switch circuit 'and keyboard system. According to the invention, the keyboard system back 23 1320903 is generated by the user touching a key or button in the keyboard system. The key or button may include one or more conductive plates, each lead = connected to the corresponding capacitor readout circuit. The digital data decoder decodes the readout circuit of the readout circuit. This matrix switch arrangement enables a small number of; the readout circuit can support many of the keys in the keyboard system, from the $ The roadway also increases the cost economy and power efficiency of the system. Generally, in accordance with the present invention, a keyboard system having 1^ capacitance readout circuitry can support up to a number of keys, where N is an integer. Matrix switch or according to the present invention The keyboard system does not have to be movable, reliable and durable. Additionally, the system can be included in an outer layer of watertight or airtight dielectric to provide protection from adverse operating conditions. Moreover, the switch according to the present invention And the keyboard system can be compact, lightweight and flexible. Moreover, they are cost effective and power efficient. According to the invention The keyboard system can be used in a variety of applications requiring data and/or command input, such as computer keyboards, PDAs, computing n, mobile phones, remote control of devices, etc. For example, a PDA can have a flexible alphanumeric keypad in accordance with the present invention. The keyboard has a relatively large area when unfolded, making it easy to use every key on the alphanumeric keypad. When not in use, the flexible keypad can be folded or rolled into a compact size that is easy to store. Although described above The specific embodiments of the present invention, but are not intended to limit the scope of the present invention. The present invention includes modifications and variations to the described embodiments that are obvious to those skilled in the art. For example, a switch system according to the present invention A single current sense circuit that controls the power consumption of the device by disconnecting the device when the user does not touch the device can be included. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing a capacitor readout circuit according to the present invention; FIG. 2 is a schematic cross-sectional view of a touch panel key according to the present invention; #FIG. 3 is a diagram showing a matrix switch or according to the present invention. A functional diagram of a keyboard system; and Figure 4 is a schematic illustration of the functionality of a telephone keypad or keypad system in accordance with the present invention. [Description of main component symbols] φ 12, 24, 32, 34, 46......... Conductive plates 52, 56, 66, 64, 72, 74, 76... Conductive plates 100 ... ......... Circuit 102............clock signal generator 105............111,121... ...current source 112 ' 122 ............switch 113 ' 123 ............capacitor 25 1320903 114 ' 115 ..... .......plate 116 ............dielectric layer 130............Comparative module 131 ........ .... first input 132 ......... second input 134 ......... differential amplifier 135 ........ ....output 138 ............capacitor 143 ............reference voltage
144 ............比較器 145 ............輸出端 150 ............鍵 160 ............開關元件 300 ............資料登錄裝置 301 ............解碼器 302、304、306 ............資料登錄端 312、314............電容讀出模組144 ............ Comparator 145 ............Output 150 ............Key 160 ..... . . . Switching element 300 ............data registration means 301 ......... decoders 302, 304, 306 ..... .......data login terminal 312, 314............capacitor readout module
322、324、326............信號輸入端 331 、 332 、 333 、 334 、 335 、 336 、 337 資料登錄鍵 400 ............小鍵盤系統 401 ............解碼器 402、404、406、408............資料登錄端 412、414、416、418............電容讀出電路 445............音頻發生器 26322, 324, 326 ......... signal input terminals 331 , 332 , 333 , 334 , 335 , 336 , 337 data login keys 400 ... ... small Keyboard system 401 ... decoders 402, 404, 406, 408 ... ... data login 412, 414, 416, 418.... ........capacitance readout circuit 445............audio generator 26