M367334 五、新型說明： 【新型所屬之技術領域】 本創作係關於一種數位多功能電錶（Digital Multi-Meter, DMM)，特別是關於一種可依照量測模式而調整參考電壓的數 位多功能電錶。 - 【先前技術】 • 按，一般習用之多功能電錶，如第1圖所示，包括一類 比前端電路10、一量測電路11、一控制電路12及一顯示器 13。類比前端電路10係將待測訊號（如電壓、電流、溫度等） 或待測元件（如電阻、電容、二極體等）轉成量測電路11可接 受的訊號，如：特定範圍内的電壓訊號。然後，量測電路11 再對此訊號進行量測，並進一步將量測結果輸出至顯示器13。 上述量測裝置11在執行量測時，除接收輸入訊號外，也 接收一參考電壓（reference voltage, Vr)，使輸入訊號相對於參 φ 考電壓的比值作為輸出結果。但，隨著待測訊號與待測元件的 不同，會使用不同的量測模式，因此，也需提供多組的參考電 壓（¥1-1，¥1-2，._.，¥1*-11)。而這些參考電壓的選擇，是由控制電 路12依據量測模式而決定的。 - 如第2圖所示，習知之多功能電錶其參考電壓（Vr)都是由 一參考電壓源(Vs)經電阻分壓而產生。參考電壓源(Vs)可以使 用能隙電路(bandgap circuit)或齊納二極體（zener diode)。而為 了讓電錶的量測結果達到一定的精準度，係利用可變電阻，使 參考電壓（Vr)的誤差能小到一定的範圍之内。因此，在電錶生 產完成時，必須使用機具調整可變電阻才能完成校正。而由於 M367334 每個量測模式都有各自的參考電壓，所以必須針對每一量測模 式都進行可變電阻的調整；因此，校正不方便、生產速度也不 容易提高，且在校正過程中容易受到外界環境影響而增加校正 的困難。另外，有些電錶為了節省成本，係將數種量測模式共 用一個參考電壓，例如：直流電壓/交流電壓/直流電流/交流電 流/二極體等量測模式共用一個參考電壓。這個方式雖然可以 節省成本，但由於每個量測模式使用的類比前端電路有所不 同，係具有不同的誤差，共用一個參考電壓係無法將所有量測 模式的前端電路誤差一併校正，因此可能會犧牲某些量測模式 的精準度。 【新型内容】 鑒於上述之創作背景中，為了解決多功能數位電表校正上 的不便、費時及犧牲精準度的問題，本創作提供一種可依據量 測模式而自動調整參考電壓的多功能量測裝置「係配置亦可寫 入/讀取記憶體及存取控制電路；因此，隨著使用者選擇不同 的量測項目，參考電壓產生電路會輸出其相對應的參考電壓。 因此，本創作之一主要目的在於提供一種可依據量測模式 而自動調整參考電壓的多功能量測裝置，此量測裝置可隨著使 用者選擇不同的量測項目，參考電壓產生電路會輸出符合此 量測項目的參考電壓；因此，各個量測模式都有獨立的參考 電壓，可一併校正類比前端電路的誤差，使量測裝置具有較 局的精準度。 本創作之另一主要目的在於提供一種可依據量測模式而 自動調整參考電壓的多功能量測裝置，此量測裝置係利用操作 M367334 介面上原有的按鍵來完成參考電壓的校正，並不需要額外的機 具；因此，校正上較方便且快速。 依據上述之目的，本創作首先提出一種可調整參考電壓的 多功能量測裝置，係包括類比前端電路、量測電路、參考電壓 產生電路、存取控制電路、控制電路及顯示器。類比前端電 路係將待測訊號或待測元件轉成適當的訊號，以供量測電路量 測並進一步將量測結果輸出至顯示裝置。而參考電壓產生電 路，係與量測電路電性連接，以輸出一參考電壓至量測電路。 存取控制電路，係與參考電壓產生電路及控制電路電性連 接，其中，當多功能量測裝置處在量測模式時，存取控制電 路係根據使用者所選擇的量測項目，而輸出一控制訊號至參考 電壓產生電路，以調整參考電壓產生電路所輸出之參考電壓。 此外，本創作也包括配置於上述量測裝置中的晶片。量測 晶片，包括：一類比前端電路，係用來接收一第一待測訊號並 輸出一第二待測訊號；一量測電路，係與類比前端電路電性連 接，以測量第二待測訊號並輸出一量測值至一顯示器；一參考 電壓產生電路，係與量測電路電性連接，以輸出一參考電壓至 量測電路；及一存取控制電路，係與參考電壓產生電路電性 連接，當量測晶片處在一量測模式時，存取控制電路係根據 使用者所選定之量測項目，而輸出一控制訊號至參考電壓產生 電路，以調整參考電壓產生電路所輸出之參考電壓。 【實施方式】 首先，請參考第3圖，係本創作之一種實施例，係一種 可調整參考電壓的量測裝置。此量測裝置20，係一多功能電 錶，具有一外殼21，且在外殼21的底部設有一對測試探針22; M367334 23，以量測一待測訊號24。除此之外，外殼21上具有一操作 介面25及一顯示器26，操作介面25上設有一旋鈕27，可經 旋轉以選擇不同的量測模式，例如：量測電壓值、量測電流值、 量測二極體等，使量測的結果顯示於顯示器26上。且，操作 介面25上具有一按鍵28，可供使用者或操作者選擇或設定之 用。 而如第4圖所示，係上述量測裝置20之方塊圖。量測裝 置20包括一旋鈕27、一按鍵28、一類比前端電路31、一量 測電路32、一參考電壓產生電路33、一電氣擦拭唯讀記憶體 (EEPROM)34、一電氣擦拭唯讀記憶體(EEPROM)控制器35、 一控制電路36及一顯示器37。類比前端電路31，主要係由訊 號偵測元件、頻率檢測電路、放大器或濾波器等所組成，可以 接收一第一待測訊號30並輸出一第二待測訊號，例如：特定 範圍内的電壓訊號。量測電路32，係與類比前端電路31電性 連接，以測量第二待測訊號並將量測結果輸出至顯示器37。 參考電壓產生電路33，係與量測電路32電性連接，以輸出一 參考電壓(Vr)至量測電路32。電氣擦拭唯讀記憶體34係儲存 有預先設定之複數個電壓參數項目。EEPROM控制器35，係 與電氣擦拭唯讀記憶體34及參考電壓產生電路33電性連接， EEPROM控制器35可以讀取儲存於電氣擦拭唯讀記憶體34 中的資料，並輸出一控制訊號至參考電壓產生電路33，以調 整參考電壓產生電路33所輸出的參考電壓。控制電路36則係 和旋鈕27、按鍵28、類比前端電路31、量測電路32、參考電 壓產生電路33以及EEPROM控制器35等電性連接。因此， 當使用者將旋鈕27調到某一量測模式時，例如：量測二極體， 控制電路36會進一步將類比前端電路31切換到量測二極體所 M367334 需的電路’並且命令EEPROM控制器35從電氣擦拭唯讀記憶 體34中讀取二極體量測所對應的電壓參數項目。EEPROM控 制器35會進一步將此電壓參數項目形成一控制訊號並輸出到 參考電壓產生電路33，使參考電壓產生電路33產生一二極體 量測所對應的參考電壓。 接著’請參閱第5圖，係上述量測裝置20其參考電壓產 ’ 生電路33之方塊圖。參考電壓產生電路33係包含一能階電路 • 331、一電壓放大器332、一數位類比轉換器（DAC)333、一輸 ^ 出多工器334。能隙電路331，係輸出一能隙參考電壓(Vref)， 電壓放大器332，係與能隙電路331電性連接，以接收能隙參 考電壓（Vref)及一增益控制輸入’並且輸出一第一電壓（Va)及 一第二電壓(Vb)。數位類比轉換器（DAC)，係與電壓放大器332 電性連接，以接收上述第二電壓（Vb)及一 DAC輸入碼，並進 一步輸出一第三電壓(Vc)。而輸出多工器334，係與電壓放大 器332及數位類比轉換器333電性連接，以接收上述第一電壓 (Va)及第三電壓(VC) ’且輸出多工器334也接收一輸出選擇訊 號，以決定第一電壓(Va)或第三電壓(Vc)作為輸出電壓；此輸 • 出電壓就是參考電壓產生電路33所輸出的參考電壓(Vr)。 上述增益控制輸入、DAC輸入碼及輸出選擇訊號即組成 所謂的電壓參數項目。增益控制輪入係包括一第一增益及一 第二增益，其中，第一增益與能隙參考電壓(Vref)的乘積係第 一電壓(Va)，而第二增益與能隙參考電壓(Vref)的乘積係第二 ' 電壓（Vb)。上述第一增益或第二增益可以係大於、小於或等 於一，使得電壓放大器332可以係對能隙參考電壓（Vre〇做放 大、衰減或不做電壓改變。當然，第一增益與第二增益也可 以係相同數值。而第三電壓係第二電壓與DAC輸入碼其對應 7 M367334 數值的乘機。 因此，當量測裝置20生產完成時，生產者必須將量測 裝置20切換到校正的狀態或模式，以取得上述電壓參數項 在校正的狀態或模式下，生產者選擇一種量測模式並藉 由操作介面25上的按鍵28來改變上述增益控制輸入、DAc 輪入碼及輸出選擇訊號，以調整參考電壓產生電路33的輸出 電壓。而當參考電壓產生電路33所輸出的參考電壓達到符合 精準度的要求時，生產者再利用按鍵28將此時的增益控制輸 入、DAC輪入碼及輸出選擇訊號儲存到電氣擦拭唯讀記憶， 將3有增益控制輸入、DAC輸入碼及輸出選擇訊號的電壓參 數項目依據量測模式存至對應的健。以上，便完成一種量 模式其參考電壓的校正。而生產者再依相同的步驟，設定 其他量測模式其參考電壓所對應的增益控制輸人、DAC輸入 竭及輸出選擇訊號並存到電氣擦拭唯讀記憶。因此，上述校 =方式僅需使用到原本操作介面25上的按鍵Μ，係不需要 卜的，具，係可提供一較方便且快速的校正。而且，不同 =量測模式都有各自獨立的參考電壓，使量測裝置2 0具有較 佳的精準度。 【圖式簡單說明】 第1圖 第2圖 第3圖 第4圖 第5圖 塊圖。 係習用之一種多功能電錶； 係習知之一種多功能電錶其參考電壓產生方式； 係本創作之一種量測裝置； 係本創作之一種量測裝置之方塊圖；及 係本創作之一種量測裝置其參考電壓產生電路之方 8 M367334 【主要元件符號說明】 20 量測裝置 21 外殼 22 測試探針 23 測試探針 24 待測訊號 • 25 操作介面 26 顯示器 27 旋钮 28 按鍵 30 待測訊號 31 類比前端電路 32 量測電路 •33 參考電壓產生電路 331 能隙電路 332 電壓放大器 ' 333 數位類比轉換器（DAC) 334 輸出多工器 34 電氣擦拭唯讀記憶體(EEPROM) 35 EEPROM控制器 9 M367334 36 37 控制電路 顯示器M367334 V. New description: [New technical field] This creation is about a Digital Multi-Meter (DMM), especially a digital multi-function meter that can adjust the reference voltage according to the measurement mode. - [Prior Art] • A conventional multi-function meter, as shown in Fig. 1, includes an analog front end circuit 10, a measuring circuit 11, a control circuit 12, and a display 13. The analog front end circuit 10 converts a signal to be tested (such as voltage, current, temperature, etc.) or a component to be tested (such as a resistor, a capacitor, a diode, etc.) into a signal acceptable to the measuring circuit 11, such as: within a specific range. Voltage signal. Then, the measuring circuit 11 measures the signal and further outputs the measurement result to the display 13. When performing the measurement, the measuring device 11 receives a reference voltage (Vr) in addition to receiving the input signal, so that the ratio of the input signal to the reference voltage is used as an output result. However, as the signal to be tested differs from the component under test, different measurement modes are used. Therefore, multiple sets of reference voltages are also required (¥1-1, ¥1-2, ._., ¥1*). -11). The selection of these reference voltages is determined by the control circuit 12 in accordance with the measurement mode. - As shown in Fig. 2, the reference voltage (Vr) of the conventional multi-function meter is generated by a reference voltage source (Vs) divided by a resistor. The reference voltage source (Vs) can use a bandgap circuit or a Zener diode. In order to achieve a certain degree of accuracy in the measurement results of the meter, a variable resistor is used to make the error of the reference voltage (Vr) small to a certain extent. Therefore, when the meter is manufactured, the tool must be used to adjust the variable resistor to complete the calibration. Since each measurement mode of M367334 has its own reference voltage, it is necessary to adjust the variable resistance for each measurement mode; therefore, the calibration is inconvenient, the production speed is not easy to improve, and it is easy to be corrected during the calibration process. The difficulty of increasing correction due to the influence of the external environment. In addition, in order to save costs, some meters share a reference voltage for several measurement modes. For example, DC voltage/AC voltage/DC current/AC current/diode measurement mode share a reference voltage. Although this method can save cost, since each measurement mode uses an analogy different from the front-end circuit, it has different errors. Sharing a reference voltage system cannot correct the front-end circuit errors of all measurement modes together, so it is possible The accuracy of some measurement modes will be sacrificed. [New content] In view of the above creative background, in order to solve the problem of inconvenience, time consuming and sacrificing precision of multi-function digital meter correction, the present invention provides a multifunctional measuring device capable of automatically adjusting the reference voltage according to the measurement mode. "The system configuration can also write/read memory and access control circuits; therefore, as the user selects different measurement items, the reference voltage generation circuit outputs its corresponding reference voltage. Therefore, one of the creations The main purpose is to provide a multi-function measuring device capable of automatically adjusting the reference voltage according to the measuring mode. The measuring device can select different measuring items according to the user, and the reference voltage generating circuit outputs the measuring item according to the measuring item. Reference voltage; therefore, each measurement mode has an independent reference voltage, which can correct the error of the analog front-end circuit together, so that the measurement device has a relatively accurate accuracy. Another main purpose of this creation is to provide a basis for quantity. A multi-function measuring device that automatically adjusts the reference voltage by measuring mode, and the measuring device utilizes operation M367334 The original button on the surface to complete the reference voltage correction does not require additional tools; therefore, the correction is more convenient and fast. According to the above purpose, the creation first proposes a multi-function measuring device capable of adjusting the reference voltage. Including analog front-end circuit, measurement circuit, reference voltage generation circuit, access control circuit, control circuit and display. The analog front-end circuit converts the signal to be tested or the component to be tested into an appropriate signal for measurement measurement and The measurement result is further output to the display device, and the reference voltage generation circuit is electrically connected to the measurement circuit to output a reference voltage to the measurement circuit. The access control circuit is electrically connected to the reference voltage generation circuit and the control circuit. a connection, wherein when the multi-function measuring device is in the measurement mode, the access control circuit outputs a control signal to the reference voltage generating circuit to adjust the reference voltage generating circuit according to the measurement item selected by the user. The reference voltage that is output. In addition, the present invention also includes a wafer disposed in the above measuring device. The chip includes: an analog front end circuit for receiving a first signal to be tested and outputting a second signal to be tested; a measuring circuit electrically connected to the analog front end circuit to measure the second signal to be tested and Outputting a measured value to a display; a reference voltage generating circuit electrically connected to the measuring circuit to output a reference voltage to the measuring circuit; and an access control circuit electrically connected to the reference voltage generating circuit When the equivalent measurement chip is in a measurement mode, the access control circuit outputs a control signal to the reference voltage generation circuit according to the measurement item selected by the user to adjust the reference voltage output by the reference voltage generation circuit. [Embodiment] First, please refer to FIG. 3, which is an embodiment of the present invention, which is a measuring device capable of adjusting a reference voltage. The measuring device 20 is a multi-function electric meter having a casing 21, and A pair of test probes 22; M367334 23 are disposed at the bottom of the outer casing 21 to measure a signal to be tested 24. In addition, the housing 21 has an operation interface 25 and a display 26, and the operation interface 25 is provided with a knob 27, which can be rotated to select different measurement modes, for example, measuring voltage value, measuring current value, The diodes and the like are measured, and the results of the measurement are displayed on the display 26. Moreover, the operation interface 25 has a button 28 for the user or operator to select or set. As shown in Fig. 4, it is a block diagram of the above measuring device 20. The measuring device 20 includes a knob 27, a button 28, an analog front end circuit 31, a measuring circuit 32, a reference voltage generating circuit 33, an electrical wiping read only memory (EEPROM) 34, and an electrical wiping read only memory. An EEPROM controller 35, a control circuit 36 and a display 37. The analog front end circuit 31 is mainly composed of a signal detecting component, a frequency detecting circuit, an amplifier or a filter, and can receive a first signal to be tested 30 and output a second signal to be tested, for example, a voltage within a specific range. Signal. The measuring circuit 32 is electrically connected to the analog front end circuit 31 to measure the second signal to be tested and output the measurement result to the display 37. The reference voltage generating circuit 33 is electrically connected to the measuring circuit 32 to output a reference voltage (Vr) to the measuring circuit 32. The electric wiping read-only memory 34 system stores a plurality of preset voltage parameter items. The EEPROM controller 35 is electrically connected to the electric wiping read-only memory 34 and the reference voltage generating circuit 33. The EEPROM controller 35 can read the data stored in the electric wiping read-only memory 34 and output a control signal to The reference voltage generating circuit 33 adjusts the reference voltage output from the reference voltage generating circuit 33. The control circuit 36 is electrically connected to the knob 27, the button 28, the analog front end circuit 31, the measuring circuit 32, the reference voltage generating circuit 33, and the EEPROM controller 35. Therefore, when the user adjusts the knob 27 to a certain measurement mode, for example, measuring the diode, the control circuit 36 further switches the analog front end circuit 31 to the circuit required for measuring the diode M367334 and commands The EEPROM controller 35 reads the voltage parameter item corresponding to the diode measurement from the electrically wiped read-only memory 34. The EEPROM controller 35 further forms a control signal for the voltage parameter item and outputs it to the reference voltage generating circuit 33, so that the reference voltage generating circuit 33 generates a reference voltage corresponding to the diode measurement. Next, please refer to Fig. 5, which is a block diagram of the reference voltage generating circuit 33 of the above measuring device 20. The reference voltage generating circuit 33 includes an energy level circuit 331, a voltage amplifier 332, a digital analog converter (DAC) 333, and an output multiplexer 334. The band gap circuit 331 outputs a bandgap reference voltage (Vref), and the voltage amplifier 332 is electrically connected to the bandgap circuit 331 to receive the bandgap reference voltage (Vref) and a gain control input 'and outputs a first Voltage (Va) and a second voltage (Vb). The digital analog converter (DAC) is electrically connected to the voltage amplifier 332 to receive the second voltage (Vb) and a DAC input code, and further outputs a third voltage (Vc). The output multiplexer 334 is electrically connected to the voltage amplifier 332 and the digital analog converter 333 to receive the first voltage (Va) and the third voltage (VC) ' and the output multiplexer 334 also receives an output selection. The signal is used to determine the first voltage (Va) or the third voltage (Vc) as an output voltage; the output voltage is the reference voltage (Vr) output by the reference voltage generating circuit 33. The above gain control input, DAC input code and output selection signal constitute a so-called voltage parameter item. The gain control wheeling system includes a first gain and a second gain, wherein a product of the first gain and the bandgap reference voltage (Vref) is a first voltage (Va), and a second gain and a bandgap reference voltage (Vref The product of ) is the second 'voltage (Vb). The first gain or the second gain may be greater than, less than, or equal to one, such that the voltage amplifier 332 may be capable of amplifying, attenuating, or not making a voltage change with respect to the bandgap reference voltage. Of course, the first gain and the second gain The same value can also be used, and the third voltage is the second voltage and the DAC input code corresponding to the value of 7 M367334. Therefore, when the production of the equivalent measuring device 20 is completed, the producer must switch the measuring device 20 to the corrected state. Or mode to obtain the above voltage parameter item in the corrected state or mode, the manufacturer selects a measurement mode and changes the gain control input, the DAc wheel input code, and the output selection signal by pressing the button 28 on the operation interface 25, To adjust the output voltage of the reference voltage generating circuit 33. When the reference voltage outputted by the reference voltage generating circuit 33 reaches the accuracy requirement, the producer uses the button 28 to input the gain control input, the DAC wheel code, and The output selection signal is stored in the electrical wipe-only memory, and the voltage reference of the gain control input, the DAC input code, and the output selection signal is 3 The project saves the reference voltage according to the measurement mode. In the above, the correction of the reference voltage of a quantity mode is completed. The producer then sets the gain control input corresponding to the reference voltage of the other measurement mode according to the same step. The input and output selection signals are stored in the electrical wiping read-only memory. Therefore, the above-mentioned school=method only needs to use the button 原 on the original operation interface 25, which is not necessary, and can provide a convenient and fast Correction. Moreover, the different=measurement modes have their own independent reference voltages, which makes the measuring device 20 have better accuracy. [Simplified illustration] Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Block diagram. A multi-function electric meter used in practice; a reference voltage generation method of a multi-function electric meter; a measurement device of the present invention; a block diagram of a measurement device of the present creation; A measuring device whose reference voltage generating circuit is 8 M367334 [Main component symbol description] 20 Measuring device 21 Shell 22 Test probe 23 Test probe 24 Signal to be tested • 25 Operation interface 26 Display 27 Knob 28 Button 30 Signal to be tested 31 Analog front end circuit 32 Measurement circuit • 33 Reference voltage generation circuit 331 Bandgap circuit 332 Voltage amplifier ' 333 Digital analog converter (DAC) 334 Output multiplexer 34 Electrical Wipe Read Only Memory (EEPROM) 35 EEPROM Controller 9 M367334 36 37 Control Circuit Display
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