M367570 五、新型說明： 【新型所屬之技術領域】 本新型是有關於一種伺服器系統，且特別是有關於一 種具控制風扇轉速之伺服器系統。 . 【先前技術】 _ 伺服器内通常具有產生高熱源電子元件，如CPU、晶 • 片組、電源及記憶體等。因此於伺服器裡面會裝設有一系 統之散熱風扇來把各電子元件產生之熱推出伺服器機殼 外，避免因過熱而造成電子元件之毁損。 在傳統之架構下，這些電子元件分別建置在不同之主 機板上，而每一主機板會根據所承載熱源附近的熱傳感器 檢測結果，產生一控制信號。通常在主機板與散熱風扇之 間會建置有一特定監測晶片，用以對這些主機板之多個控 制信號進行處理，輸出給散熱風扇一運行信號，讓散熱風 Φ ' 扇據此進行轉動。 - 由於傳統的散熱風扇控制電路，需要一顆特定之監測 晶片來處理控制信號，其控制成本高。因此對於一種可降 低成本又可精確控制風扇轉速之電路存有一種需求。 【新型内容】 因此，本新型之一態樣是在提供一種不需要特定監測 晶片又能控制風扇轉速之伺服器系統。 依據本新型一實施例，一種伺服器系統，其中伺服器 M367570 系統包括多個主機板，一控制電路以及一系統風扇。其中 每一主機板會輸出一脈波寬度調變信號。控制電路至少包 含複數個充放電路徑，其中每一該些充放電路徑接收對應 主機板所輸出之一脈波寬度調變信號，來對對應該充放電 路徑進行充放電操作而產生一端電壓，一比較器用以比較 該些充放電路徑所產生之端電壓，並據以輸出一比較結果 ' 信號，以及一選擇器，並根據該比較結果訊號輸出該些脈 - 波寬度調變信號其中之一。散熱風扇根據該選擇器輸出之 • 該脈波寬度調變信號轉動。 依據本新型一實施例，其中每一該些充放電路徑至少 包含一串聯之電阻與一電容，其中該電阻為100k歐姆，其 中該電容為0.01 u法拉。 其中每一主機板係根據所承載熱源附近的熱傳感器檢 測結果輸出對應之脈波寬度調變信號。而該端電壓為被該 脈波寬度調變信號對該電容進行充放電操作後所產生。 本新型至少具有下列優點。藉由比較器與選擇器之結 • 合選擇輸出之脈波寬度調變（PWM)信號，可取代傳統之 ' 特定監測晶片，降低產品成本。此外，僅需一充放電路徑， 即可比較各輸入PWM信號佔空比之大小，大量降低電路 之複雜度。 【實施方式】 本新型即是利用一充放電路徑將各主機板分別產生之 PWM信號轉換成一對應電壓輸出，由於佔空比越大之 PWM信號，轉換成之電壓越大。依此本新型再利用一比較 5 M367570 器比較各轉換出之電壓，來挑選出 信號，以鮮卜散•额此對應之™ 參閱第u所示為根據本比進行轉動。 :下：以具有兩主機板之伺服辱為實施例進行本新型之說 月，然而本新型不以此實施例為限，’ 5 機板之伺服ϋ彳、統巾。 、σ〜用於具多個主M367570 V. New description: [New technical field] The present invention relates to a server system, and in particular to a server system with a control fan speed. [Prior Art] _ The server usually has high-heat source electronic components such as CPU, chip set, power supply, and memory. Therefore, a cooling fan of the system is installed in the server to push the heat generated by each electronic component out of the servo casing to avoid damage of the electronic component due to overheating. Under the traditional architecture, these electronic components are respectively built on different mainboards, and each motherboard generates a control signal based on the thermal sensor detection results near the heat source carried. A specific monitoring chip is usually formed between the motherboard and the cooling fan to process a plurality of control signals of the motherboard, and output a signal to the cooling fan to cause the cooling air Φ' to rotate according to the fan. - Due to the traditional cooling fan control circuit, a specific monitoring chip is required to process the control signal, which is costly to control. Therefore, there is a need for a circuit that can reduce the cost of the fan and accurately control the fan speed. [New content] Therefore, one aspect of the present invention is to provide a server system that can control the fan speed without requiring a specific monitoring chip. In accordance with an embodiment of the present invention, a server system wherein the server M367570 system includes a plurality of motherboards, a control circuit, and a system fan. Each of the motherboards outputs a pulse width modulation signal. The control circuit includes at least a plurality of charging and discharging paths, wherein each of the charging and discharging paths receives a pulse width modulation signal outputted by the corresponding motherboard to generate a voltage at one end of the charging and discharging operation corresponding to the charging and discharging path, The comparator is configured to compare the terminal voltages generated by the charging and discharging paths, and output a comparison result 'signal, and a selector, and output one of the pulse-wave width modulation signals according to the comparison result signal. The cooling fan rotates according to the pulse width modulation signal output by the selector. According to an embodiment of the present invention, each of the charging and discharging paths includes at least a series resistor and a capacitor, wherein the resistor is 100 k ohms, wherein the capacitor is 0.01 u farad. Each of the motherboards outputs a corresponding pulse width modulation signal according to the thermal sensor detection result in the vicinity of the carried heat source. The terminal voltage is generated after the capacitor is charged and discharged by the pulse width modulation signal. The present invention has at least the following advantages. By combining the output of the comparator with the selector, the pulse width modulation (PWM) signal of the output can be selected to replace the traditional 'specific monitor wafers, reducing product cost. In addition, only one charge and discharge path is needed to compare the duty ratio of each input PWM signal, which greatly reduces the complexity of the circuit. [Embodiment] The present invention converts a PWM signal generated by each motherboard into a corresponding voltage output by using a charging and discharging path. The PWM signal converted to a larger duty ratio is converted into a larger voltage. According to the comparison, the 5 M367570 compares the voltages of the respective converters to select the signals, and the corresponding TMs are referred to as u, and the rotation is performed according to the ratio. : Bottom: The present invention is carried out in the form of a server with two motherboards. However, the present invention is not limited to this embodiment, and the servo ϋ彳 and the towel of the '5 board. , σ~ for multiple masters
本新型之祠服器散熱風扇控制電路2〇〇包括兩 路徑20i和202、-比較器203和—選擇器2〇4。立中兩主 機板207和208分別麵接輸入端點2〇5和2〇6，主機板2〇7 根據其所承載熱源附近的熱傳感器檢測結果，產生一具對 應佔空比（duty cycle)之脈波寬度調變信號pWM卜^機 板208亦根據其所承載熱源附近的熱傳感器檢測結果，產 生一具對應佔空比之脈波寬度調變信號PWM2。 其中脈波寬度調變信號PWM1透過輸入端點2〇5對充 放電路徑2〇1進行充放電操作。而脈波寬度調變信號pwM 2透過輸入端點206對充放電路徑202進行充放電操作。 此外，脈波寬度調變信號PWM 1*PWM 2，亦會傳輸給 選擇器204，供後續之選擇操作之用。 在一實施例中，係由一串聯之電阻與電容組成本新型 之，一充放電路徑201和202,其中電阻大小為1〇〇k歐姆， 電容大小為G.Glu法拉。在此實_下，#脈波寬度調變 信號PWM1和PWM2具有不同佔空㈣ 放電之時間比例也會有不同，對—佔空比較大的脈波寬度 調變信號而言，對電容進行充電之_大於佔^比較小之 脈波寬度調變信號，因此在一充放電時間經過後，兩充放 M367570 電路徑201和202中之電容將出現不同之端電壓V1與V2。 在本新型中，比較器203之正負輸入端會分別與兩充 放電路徑201和202中之電容端點耦接，藉以比較兩電容 之端電壓VI與V2大小。其中比較器2〇3之正輸入端耦接 充放電路徑201之電容端點，而比較器2〇3之負輸入端耦 接充放電路徑202之電容端點。當端電壓V1大於V2時， 比較器203輸出一正極性訊號，代表從端點2〇5輸入之脈 -波寬度調變仏號PWM 1具有較大之佔空比。此正極性訊號 • 會被傳送給一選擇器204，此時選擇器204會根據此正極 性訊號選擇脈波寬度調變信號i，並輸出給一散熱風 扇209，讓散熱風扇依脈波寬度調變信號pWM丄之佔空比 進行轉動。而在另一實施例中，當端電壓V1小於V2，比 較器203輸出一負極性訊號，代表從端點2〇6輸入之脈波 寬度调變彳§號PWM2具有較大之佔空比。此負極性訊號會 被傳送給選擇器204,此時選擇器204會根據此負極性訊 號選擇脈波寬度調變信號PWM 2，並輸出給一散熱風扇 φ 209 ’讓散熱風扇依脈波寬度調變信號Pwm 2之佔空比進 -行轉動。其中選擇器204，例如為一多工器。 參閱第2圖所示為本新型應用於一具四主機板伺服器 之概略圖示。其中主機板315根據其所承載熱源附近的熱 傳感器檢測結果’產生一具對應佔空比（dutycycle)之脈 波寬度調變信號PWM 1。主機板316亦根據其所承載熱源 附近的熱傳感器檢測結果，產生一具對應佔空比之脈波寬 度調變信號PWM 2。其中脈波寬度調變信號·ρWM丨和 PWM 2，分別經由對應之充放電路徑3〇4和3〇5對路徑中 M367570 之電容C進行充放電操作。此外，脈波寬度調變信號PWM 1和PWM 2，亦會傳輸給選擇器301，供後續之選擇操作 之用。比較器301之正負輸入端會分別與兩充放電路徑304 和305中之電容端點耦接，藉以比較兩電容之端電壓大 小。相似的，主機板317根據其所承載熱源附近的熱傳感 器檢測結果，產生一具對應伯空比（duty cycle )之脈波寬 度調變信號PWM 3。主機板318亦根據其所承載熱源附近 的熱傳感器檢測結果，產生一具對應佔空比之脈波寬度調 變信號PWM4。其中脈波寬度調變信號PWM3和PWM4, 分別經由對應之充放電路徑306和307對路徑中之電容C 進行充放電操作。此外，脈波寬度調變信號PWM 6和PWM 7，亦會傳輸給選擇器309，供後續之選擇操作之用。比較 器302之正負輸入端會分別與兩充放電路徑306和307中 之電容端點耦接，藉以比較兩電容之端電壓大小。 另一方面，選擇器308和選擇器309之輸出亦會直接 傳輸給選擇器310，供後續選擇之用。在一實施例中，當 脈波寬度調變信號PWM 1較脈波寬度調變信號PWM 2具 有較大之佔空比，此時比較器301會輸出一正極性訊號給 選擇器308，讓選擇器308據此正極性訊號選擇脈波寬度 調變信號PWM 1輸出。而當脈波寬度調變信號PWM 4較 脈波寬度調變信號PWM3具有較大之佔空比，此時比較器 301會輸出一負極性訊號給選擇器309,讓選擇器309據此 負極性訊號選擇脈波寬度調變信號PWM 4输出。此時，脈 波寬度調變信號PWM 1和脈波寬度調變信號PWM 4亦會 傳輸給選擇器310，供後續選擇之用。 M367570 接著，選擇器308輸出之擇脈波寬度調變信號PWM 1 和選擇器309輸出脈波寬度調變信號PWM 4，會分別經由 對應之充放電路徑311和312對路徑中之電容C進行充放 電操作。此外，脈波寬度調變信號PWM 1和PWM 4，亦 會傳輸給選擇器310，供後續之選擇操作之用。比較器303 之正負輸入端會分別與兩充放電路徑311和312中之電容 端點耦接，藉以比較兩電容之端電壓大小。在一實施例中， 當脈波寬度調變信號PWM 4較脈波寬度調變信號PWM 1 具有較大之佔空比，此時比較器303會輸出一負極性訊號 給選擇器310，讓選擇器310據此負極性訊號選擇脈波寬 度調變信號PWM 4，並輸出給一散熱風扇319，讓散熱風 扇依脈波寬度調變信號PWM4之佔空比進行轉動。 由上述本新型實施方式可知，應用本新型具有下列優 點。藉由比較器與選擇器之結合選擇輸出之PWM信號， 可取代傳統之特定監測晶片，降低產品成本。此外，僅需 一充放電路徑，即可比較各輸入PWM信號佔空比之大小， 大量降低電路之複雜度。 雖然本新型已以實施方式揭露如上，然其並非用以限 定本新型，任何熟習此技藝者，在不脫離本新型之精神和 範圍内，當可作各種之更動與潤飾，因此本新型之保護範 圍當視後附之申請專利範圍所界定者為準。 【圖式簡單說明】 為讓本新型之上述和其他目的、特徵、優點與實施例 能更明顯易懂，所附圖式之說明如下： M367570 第1圖所示為根據本新型之伺服器散熱風扇控制電 路。 第2圖所示為根據本新型另一實施例之伺服器散熱風 扇控制電路。 【主要元件符號說明】 ' 209和319散熱風扇 ' 207、208、315、316、317 和 318 主機板 • 200散熱風扇控制電路 201和202充放電路徑 203比較器 204選擇器 205和206輸入端點 304、305、306、307、311 和 312 充放電路徑 301、302和303比較器 308、309和310選擇器 10The novel heat sink fan control circuit 2 of the present invention includes two paths 20i and 202, a comparator 203, and a selector 2〇4. The two main boards 207 and 208 are respectively connected to the input terminals 2〇5 and 2〇6, and the main board 2〇7 generates a corresponding duty cycle according to the detection result of the thermal sensor near the heat source carried by the main board. The pulse width modulation signal pWM board 208 also generates a pulse width modulation signal PWM2 corresponding to the duty ratio according to the detection result of the thermal sensor near the heat source carried therein. The pulse width modulation signal PWM1 performs a charge and discharge operation on the charge and discharge path 2〇1 through the input terminal 2〇5. The pulse width modulation signal pwM 2 charges and discharges the charge and discharge path 202 through the input terminal 206. In addition, the pulse width modulation signal PWM 1*PWM 2 is also transmitted to the selector 204 for subsequent selection operations. In one embodiment, the present invention comprises a series of resistors and capacitors, a charge and discharge path 201 and 202, wherein the resistance is 1 〇〇k ohm and the capacitance is G.Glu farad. In this case, the pulse width modulation signals PWM1 and PWM2 have different duty cycles (four). The time ratio of the discharge will also be different. For the pulse width modulation signal with a larger duty cycle, the capacitor is charged. _ is greater than the smaller pulse width modulation signal, so after a charge and discharge time, the capacitance of the two charging and discharging M367570 electrical paths 201 and 202 will have different terminal voltages V1 and V2. In the present invention, the positive and negative inputs of the comparator 203 are coupled to the capacitor terminals of the two charge and discharge paths 201 and 202, respectively, to compare the terminal voltages VI and V2 of the two capacitors. The positive input terminal of the comparator 2〇3 is coupled to the capacitor terminal of the charge and discharge path 201, and the negative input terminal of the comparator 2〇3 is coupled to the capacitor terminal of the charge and discharge path 202. When the terminal voltage V1 is greater than V2, the comparator 203 outputs a positive polarity signal, which represents the pulse-wave width modulation signal PWM 1 input from the terminal 2〇5 having a larger duty ratio. The positive polarity signal will be transmitted to a selector 204. At this time, the selector 204 selects the pulse width modulation signal i according to the positive polarity signal, and outputs it to a cooling fan 209 to adjust the cooling fan according to the pulse width. The duty cycle of the variable signal pWM丄 is rotated. In another embodiment, when the terminal voltage V1 is less than V2, the comparator 203 outputs a negative polarity signal, which represents that the pulse width modulation input from the terminal 2〇6 has a larger duty ratio. The negative polarity signal is transmitted to the selector 204. At this time, the selector 204 selects the pulse width modulation signal PWM 2 according to the negative polarity signal, and outputs it to a cooling fan φ 209 'to make the cooling fan adjust according to the pulse width. The duty cycle of the variable signal Pwm 2 is rotated in a row. The selector 204 is, for example, a multiplexer. Referring to Fig. 2, a schematic diagram of the present invention applied to a four-board server is shown. The motherboard 315 generates a pulse width modulation signal PWM 1 corresponding to a duty cycle according to the thermal sensor detection result near the heat source carried by the motherboard 315. The motherboard 316 also generates a pulse width modulation signal PWM 2 corresponding to the duty cycle based on the thermal sensor detection result near the heat source it carries. The pulse width modulation signal·ρWM丨 and PWM 2 are charged and discharged to the capacitor C of the M367570 in the path via the corresponding charging and discharging paths 3〇4 and 3〇5, respectively. In addition, the pulse width modulation signals PWM 1 and PWM 2 are also transmitted to the selector 301 for subsequent selection operations. The positive and negative inputs of the comparator 301 are coupled to the capacitor terminals of the two charge and discharge paths 304 and 305, respectively, to compare the terminal voltage levels of the two capacitors. Similarly, the motherboard 317 generates a pulse width modulation signal PWM 3 corresponding to a duty cycle based on the result of the thermal sensor detection in the vicinity of the heat source it carries. The motherboard 318 also generates a pulse width modulation signal PWM4 corresponding to the duty cycle based on the thermal sensor detection result near the heat source carried by the motherboard. The pulse width modulation signals PWM3 and PWM4 perform charging and discharging operations on the capacitor C in the path via the corresponding charging and discharging paths 306 and 307, respectively. In addition, the pulse width modulation signals PWM 6 and PWM 7 are also transmitted to the selector 309 for subsequent selection operations. The positive and negative inputs of the comparator 302 are coupled to the capacitor terminals of the two charge and discharge paths 306 and 307, respectively, to compare the voltages of the terminals of the two capacitors. On the other hand, the outputs of selector 308 and selector 309 are also directly transmitted to selector 310 for subsequent selection. In an embodiment, when the pulse width modulation signal PWM 1 has a larger duty ratio than the pulse width modulation signal PWM 2, the comparator 301 outputs a positive polarity signal to the selector 308 for selection. The 308 selects the pulse width modulation signal PWM 1 according to the positive polarity signal. When the pulse width modulation signal PWM 4 has a larger duty ratio than the pulse width modulation signal PWM3, the comparator 301 outputs a negative polarity signal to the selector 309, so that the selector 309 has a negative polarity. The signal selects the pulse width modulation signal PWM 4 output. At this time, the pulse width modulation signal PWM 1 and the pulse width modulation signal PWM 4 are also transmitted to the selector 310 for subsequent selection. M367570, the selector pulse width modulation signal PWM 1 output by the selector 308 and the pulse width modulation signal PWM 4 output by the selector 309 respectively charge the capacitor C in the path via the corresponding charging and discharging paths 311 and 312, respectively. Discharge operation. In addition, the pulse width modulation signals PWM 1 and PWM 4 are also transmitted to the selector 310 for subsequent selection operations. The positive and negative inputs of the comparator 303 are coupled to the capacitor terminals of the two charge and discharge paths 311 and 312, respectively, to compare the terminal voltages of the two capacitors. In an embodiment, when the pulse width modulation signal PWM 4 has a larger duty ratio than the pulse width modulation signal PWM 1, the comparator 303 outputs a negative polarity signal to the selector 310 for selection. Based on the negative polarity signal, the device 310 selects the pulse width modulation signal PWM 4 and outputs it to a heat dissipation fan 319 for rotating the cooling fan according to the duty ratio of the pulse width modulation signal PWM4. As can be seen from the above-described embodiments of the present invention, the application of the present invention has the following advantages. By combining the output PWM signal with the combination of the comparator and the selector, it can replace the traditional specific monitoring chip and reduce the product cost. In addition, only one charge and discharge path is needed to compare the duty ratio of each input PWM signal, which greatly reduces the complexity of the circuit. Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Any one skilled in the art can make various changes and retouchings without departing from the spirit and scope of the present invention. The scope is subject to the definition of the scope of the patent application attached. BRIEF DESCRIPTION OF THE DRAWINGS In order to make the above and other objects, features, advantages and embodiments of the present invention more obvious, the description of the drawings is as follows: M367570 Figure 1 shows the heat dissipation of the server according to the present invention. Fan control circuit. Fig. 2 is a diagram showing a servo heat dissipation fan control circuit according to another embodiment of the present invention. [Main component symbol description] '209 and 319 cooling fans' 207, 208, 315, 316, 317 and 318 motherboard • 200 cooling fan control circuits 201 and 202 charge and discharge path 203 comparator 204 selectors 205 and 206 input terminals 304, 305, 306, 307, 311, and 312 charge and discharge paths 301, 302, and 303 comparators 308, 309, and 310 selectors 10