578089 五、發明說明（1) ^—— 發明領域： i 本發明係關於一種矩陣式鍵盤電路，尤其是關於· 種低雜訊與低電磁干擾（EMI)之矩陣式鍵盤電路，、可 應用於各類電子產品所需的鍵盤，例如，電腦、自動 制、電話、甚至醫療產品等等之輸入鍵盤。 發明背景： 矩陣式鍵盤電路與一對一輸入鍵盤之比較，其好處 在於當鍵盤所需的按鍵數量超過四個以上時，矩陣式鍵 盤電路所需的輸入/輸出元件就會減少，硬體成本相對 降低’因此被廣泛地運用。 一般而言，傳統之矩陣式鍵盤電路，請參考圖一， 係利用數個「列（Row)」依序地發送脈衝信號以進行 掃描，再配合數個「行（Co 1 umn)」偵測矩陣中的被按 的按鍵位置。易言之，傳統之矩陣式鍵盤電路係藉由一 組（R0W/C0L)脈衝輸出信號埠（port)，不斷地依序 掃描，當按鍵被按下時（例如，按下K1鍵時），配合另 —組（C0L/R0W)輸入埠（Port.)，讀回按鍵開關狀態（ 例如，R〇W1 = 0，且COL1=0)，因此可計算出按鍵的位置 (即為K1所在）’請參考表一實施例之真值表。 一般矩陣式鍵盤電路需要週期地發送脈衝信號（典 型地，約小於2 0 m s的掃描週期），以掃描按鍵之開關 狀態，然而脈衝信號易產生高頻諧波信號，這正是電磁 578089 五、發明說明（2) 干擾（EMI)雜訊的來源，甚至有可能是音頻電路的雜 音來源。對於目前的電子資訊產品檢驗要求來說，無疑 地會造成很大的困擾。 發明目的： 有鑒於上述之問題點，本發明提供一種低雜訊與低 電磁干擾之矩陣式鍵盤電路，但是仍保有矩陣式鍵盤電 路低成本之優點。 本發明之主要目的是提供一種降低雜訊之矩陣式鍵 盤電路。 本發明之另一目的係提供一種降低電磁干擾之矩陣 式鍵盤電路。 本發明之再一目的係提供一種降低成本之矩陣式鍵 盤電路。 發明概述： 一種矩陣式鍵盤電路，用以將一按鍵輸入之位置編 碼，該電路包含一第一端輸入埠（Port)，用以讀回列 (ROW)的信號；一第二端輸入埠（Port)，用·以讀回 行（COLUMN)的信號；以及一接地端，係.介於該第一端 輸入埠與該第二端輸入埠之交叉位置；其中該按鍵輸入 之位置之解碼係藉由讀取該第一端輸入埠與該第二端輸578089 V. Description of the invention (1) ^ —— Field of invention: i The present invention relates to a matrix keyboard circuit, in particular, a matrix keyboard circuit with low noise and low electromagnetic interference (EMI), which can be applied to Keyboards for all kinds of electronic products, such as input keyboards for computers, automatic systems, telephones, and even medical products. Background of the Invention: The comparison between a matrix keyboard circuit and a one-to-one input keyboard has the advantage that when the number of keys required by the keyboard exceeds four or more, the input / output components required by the matrix keyboard circuit are reduced, and the hardware cost is reduced. 'Relative reduction' is therefore widely used. In general, the traditional matrix keyboard circuit, please refer to Figure 1. It uses several "rows" to send pulse signals in order to scan, and then cooperates with several "co 1 um" detection The position of the pressed key in the matrix. In other words, the traditional matrix keyboard circuit uses a set of (R0W / C0L) pulse output signal ports to continuously scan sequentially when the keys are pressed (for example, when the K1 key is pressed). Cooperate with another group (C0L / R0W) input port (Port.), Read back the state of the key switch (for example, ROW1 = 0, and COL1 = 0), so the position of the key (that is, where K1 is) can be calculated. ' Please refer to the truth table of the embodiment in Table 1. Generally, the matrix keyboard circuit needs to send pulse signals periodically (typically, a scanning period less than 20 ms) to scan the switch state of the keys. However, pulse signals are prone to generate high-frequency harmonic signals. This is exactly the electromagnetic 578089. Description of the Invention (2) The source of interference (EMI) noise may even be the source of noise in audio circuits. For the current inspection requirements of electronic information products, it will undoubtedly cause great confusion. Object of the invention: In view of the above problems, the present invention provides a matrix keyboard circuit with low noise and low electromagnetic interference, but still has the advantage of low cost of the matrix keyboard circuit. The main object of the present invention is to provide a matrix keyboard circuit with reduced noise. Another object of the present invention is to provide a matrix keyboard circuit for reducing electromagnetic interference. Another object of the present invention is to provide a matrix keyboard circuit with reduced cost. SUMMARY OF THE INVENTION: A matrix keyboard circuit is used to encode the position of a key input. The circuit includes a first-end input port (Port) for reading back a row signal; a second-end input port ( Port), using the signal of the read-back line (COLUMN); and a ground terminal, which is located at the intersection between the first input port and the second input port; where the decoding of the key input position is By reading the first input port and the second input
第5頁 578089 五、發明說明（3) 入埠之信號依表一換算獲得。 詳細說明與較佳實施例： 有關本發明為達成上述之目的，所採用之技術、手 段及具體結構特徵，茲舉較佳可行之實施例，並藉由圖 示說明而更進一步揭示明瞭，詳如下述。 本發明提供一種低雜訊與低電磁干擾之矩陣式鍵盤 電路。一般說來鍵盤的形式如圖三A所示即為電腦輸入 用的鍵盤3 1 1，按鍵3 1 1 ;圖三B係一般銀行用的密碼輸 入裝置3 2 0，按鍵3 2 1。雖然本發明之實施例如圖三A與 三B所示，然，其並非用以限制本發明，如熟悉本項技 藝者所周知，本發明可應用於各式之輸人鍵盤，例如遙 控器、電話、自動控制，甚至醫療電子、航空電子產品 等等。 請參考圖四A，係本發明所提供一種矩陣式鍵盤電 路、用以將一按鍵輸入之位置資料編碼及解碼，該電路 包含一第一端輸入埠（port) 41，用以讀回一列 (ROW)的信號；一第二端輸入埠（port) 42，用以讀 回一行（COLUMN)的信號；以及一接地端43，係連接於 該第一端輸入埠與該第二端輸入埠之交叉位置；其中該 按鍵輸入之位置資料係藉由讀取該第一端輸入埠41與該 第二端輸入埠，4 2之信號獲得。上述之實施例係可藉由三 578089 五、發明說明（4) " ^ ------ =二開（N0rmal 0pen)接點來組成的按鍵開關，除此 膠來構ί可Γ如®B所示，制㈣電路板和導電橡 有行Γ「ητ ; P刷電路板的上的每一個Key Pad須同時具 )、列（R〇W)、以·及地（GND)信號三個接點。由 個接Μ仃列之信號讀取是藉由行列相乘，因此，至少四 以上鍵以上，其成本才明顯地降低。至少需要四個按鍵 _ Λ Α更進一步來說，該第一端輸入埠4 1與該該第二端 = 42分別進一步連接一電阻至電源，藉以視為正邏 〇 〇g i c 1 )，其輸出即如表一實施例所示之真值表 曰此’本發明所提供之矩陣式鍵盤電路，不再需要發 送脈衝=號’故可免除高頻諧波信號的產生! 一易&之，本電路保持了矩陣的基本結構，請參考圖 二之電路不意圖，仍然用Ν行乘以Μ列來決定所需按鍵的 =數（Ν X μ) ’然後，在每一行與列的交叉位置上加 =接!^的1號組成一個按鍵開關，在所有按鍵的行列線 ▲:皆接提昇電阻，使處理器視為正邏輯（1〇gic” r) ^ 當其中任一位置的按·鍵被按下時，就使得該位置 '了列.線，路與接地信號短路，該行列因此變成零電位 鍵二1: 〇 )，最後處理器再由該行列的順序計算出按 本發明X 2可，可參考表一對應其按鍵之位置。因此， =傳統矩陣式鍵盤電路低成本之優點，還 大地降低雜：ΪI忐。對於各類電子產品來說5可大 以有二可能，進而對電子產業（_驗）可 578089 五、發明說明（5) 雖然本發明已以較佳實施例揭露如上，然其並非用 以限定本發明，任何熟悉本技藝之人士，在不脫離本發 明之精神和範圍内，當可做些許之更動與潤飾，例如， 可將所有行列p u 1 1 d 〇 w η至地電位，改用電源信號介入 開關，則只是信號邏輯完全相反，其電路原理還是一樣 ，因此本發明之保護範圍當視後附之申請專利範圍所界 定者為準。 .Page 5 578089 V. Description of the invention (3) The signal of entering the port is obtained by conversion according to Table 1. Detailed description and preferred embodiments: Regarding the technology, means and specific structural features used by the present invention to achieve the above-mentioned objectives, the preferred and feasible embodiments are given, and are further disclosed through the illustrations. As follows. The invention provides a matrix keyboard circuit with low noise and low electromagnetic interference. Generally speaking, the form of the keyboard is shown in Figure 3A, which is the keyboard for computer input 3 1 1 and keys 3 1 1; Figure 3 B is the password input device 3 2 0 for general banks, and the key 3 2 1. Although the embodiments of the present invention are shown in FIGS. 3A and 3B, they are not intended to limit the present invention. As is well known to those skilled in the art, the present invention can be applied to various input keyboards, such as remote controllers, Phones, automatic controls, and even medical electronics, avionics, and more. Please refer to FIG. 4A, which is a matrix keyboard circuit provided by the present invention for encoding and decoding the position data of a key input. The circuit includes a first-end input port 41 for reading back a row ( ROW) signal; a second end input port (port) 42 for reading back a row of signals (COLUMN); and a ground terminal 43 connected between the first end input port and the second end input port Cross position; the position data of the key input is obtained by reading the signals from the first input port 41 and the second input port, 4 2. The above embodiment is a key switch composed of three 578089 five, invention description (4) " ^ ------ = two open (N0rmal 0pen) contacts, in addition to this glue to construct As shown in ®B, the circuit board and conductive rubber have rows Γ "ητ; each Key Pad on the P brush circuit board must have at the same time), column (R0W), and ground (GND) signals. The number of contacts is read by the signal from each column. Multiplication is performed by rows and columns. Therefore, the cost is significantly reduced by at least four or more keys. At least four keys are needed. The first end input port 41 and the second end = 42 are further connected to a resistor to the power supply respectively, so that it is regarded as positive logic 0 gic 1), and its output is the truth value table as shown in the embodiment of Table 1. 'The matrix keyboard circuit provided by the present invention no longer needs to send pulses =' so it can avoid the generation of high-frequency harmonic signals! Yi Yi & This circuit maintains the basic structure of the matrix, please refer to Figure 2 The circuit does not intend to use N rows multiplied by M columns to determine the required number of keys (N X μ) 'Then, in each row and At the cross position of +, the number 1 connected with = ^ is used to form a key switch. All the rows and columns of the keys ▲: are connected to the lifting resistor, so that the processor is regarded as positive logic (10gic ”r) ^ When any of the positions When the key of the key is pressed, the position is left in the column. The line, the circuit and the ground signal are short-circuited, so the row and column become zero potential key 2: 1: 〇), and finally the processor calculates the key from the order of the row and column. The X 2 of the present invention is ok, please refer to Table 1 corresponding to the position of its keys. Therefore, the traditional matrix keyboard circuit has the advantage of low cost and greatly reduces noise: ΪI 忐. For various types of electronic products, 5 may have two possibilities, and then the electronics industry (_Examination) may be 578089. 5. Description of the invention (5) Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit In the present invention, anyone familiar with the art can make some modifications and retouches without departing from the spirit and scope of the present invention. For example, all ranks pu 1 1 d 0w η to ground potential can be used instead. The signal intervention switch is just the opposite of the signal logic, and its circuit principle is still the same. Therefore, the protection scope of the present invention shall be determined by the scope of the attached patent application. .
578089 圖式簡單說明 圖式與列表之簡單說明： 不意圖， 路不意圖， 之應用；以及 例0 之真值表。 圖一係傳統之矩陣式鍵盤電路 圖二係本發明之矩陣式鍵·盤電 圖三A與圖三B係本發明實施例 圖四A與圖四B係本發明之實施 表一係矩陣式鍵盤電路實施例 主要元件符號說明： 鍵盤裝置------310、 320 按鍵----------311' 321 578089 表一 按鍵 列(ROW) Ί~2 3 4 行(C0L) 12 3 4 K1 0 1 1 1…0 1 1 1 K2 0 11 1…1 0 1 1 K3 0 1 1 1…1 1 0 1 K4 0 1 1 1…1 1 1 0578089 Schematic illustrations Schematic and list descriptions: Unintended, unintended, application; and truth table of Example 0. Fig. 1 is a circuit diagram of a traditional matrix keyboard. Fig. 2 is a matrix key of the present invention. Panel diagrams 3A and 3B are embodiments of the present invention. Figs. 4A and 4B are embodiments of the present invention. Table 1 is a matrix keyboard. Description of the symbols of the main components of the circuit embodiment: Keyboard device ------ 310, 320 keys ---------- 311 '321 578089 Table 1 key row (ROW) Ί ~ 2 3 4 rows (C0L) 12 3 4 K1 0 1 1 1… 0 1 1 1 K2 0 11 1… 1 0 1 1 K3 0 1 1 1… 1 1 0 1 K4 0 1 1 1… 1 1 1 0
Km+1 1 0 1 1…0 1 1 1 Km+2 1 0 1 1…1 0 1 1 Km+3 1 0 1 1…1 1 0 1 Km+4 1 0 1 1…1 1 1 0 K2m+1 K2m+2 K2m+3 K2m+4 110 1 110 1 110 1 110 1 0 111 10 11 110 1 1110 K3m+1 K3m+2 K3m+3 K3m+4 1110 1110 1110 1110 0 111 10 11 110 1 1110Km + 1 1 0 1 1… 0 1 1 1 Km + 2 1 0 1 1… 1 0 1 1 Km + 3 1 0 1 1… 1 1 0 1 Km + 4 1 0 1 1… 1 1 1 0 K2m + 1 K2m + 2 K2m + 3 K2m + 4 110 1 110 1 110 1 110 1 110 1 0 111 10 11 110 1 1110 K3m + 1 K3m + 2 K3m + 3 K3m + 4 1110 1110 1110 1110 0 111 10 11 110 1 1110