201038026 六、發明說明： 【發明所屬之技術頌威】 [0001]本發明涉及一種差分訊號線及差分訊號線偏移量之補償 方法。 [先前技術] [0002] 一般而言，印刷電路板之噪音為共模訊號。藉此，印刷 電路板常利用極性相反之訊號，即差分訊號，如p c卜 Express、SATA等，實現訊號奇模傳輸’並於訊號接收 端使用差分放大器對差分訊號放大以濾除共模雜訊。差 分訊號之傳輸線一般由一對傳輸線組成。由於主機板設 有各種位置需求之電子元件，使得習知差分訊號線之兩 條傳輸線無法等長，進而使得差分訊號無法同時到達接 收端並極性相反狀態（如圖4a及5a所示）°為了保證差 分訊號同時到達接收端並保持極性相反狀態’於差分訊 號傳輸之過程中，差分訊號之傳輸線必須等長。習知技 術即透過延遲布線法加長較短一方之長度以保證差分訊 號線等長。然，人為操作延遲布線法並不能使得差分訊 號傳輸線真正等長，從而造成訊號傳輸品質下降（如圖 4b及5b所示）。 【發明内容】 [0003] 鑒於以上内容，有必要提供一種提高訊號傳輸品質之差 分訊號線及差分訊號線偏移量之補償方法。 [0004] 一種差分訊號線偏移量之補償方法，用於補償一差分訊 號線中一第一傳輸線及一第二傳輸線間之偏移量，該補 償方法包括以下步驟：計算訊號於該第一傳輸線之傳輪 098110957 表單煸號A0101 第3頁/共24頁 0982017971-0 201038026 速度；測量該第一傳輸線及第二傳輸線之長度；計算訊 號於該第一傳輸線之傳輸時間；以訊號於該第一傳輸線 及第二傳輸線之傳輸時間相等為條件，計算得到第一傳 輸線與第二傳輸線之介電常數之對應關係；以及改變第 一傳輸線或第二傳輸線之介電常數以符合該對應關係。 [0005] 一種差分訊號線，包括一第一傳輸線及一第二傳輸線， 該第一傳輸線之介電常數為一第一介電常數、長度為一 第一長度，該第二傳輸線之介電常數為一第二介電常數 、長度為一第二長度，且滿足 了 = T~ ，其中，S1為該第一傳輸線之長度，εΐ為該第一介電常 數，S2為該第二傳輸線之長度，ε2為該第二介電常數， C為光速。 [0006] 相較習知技術，該印刷電路板及補償方法透過該第一電 介質及第二電介質於該第一傳輸線與第二傳輸線上之分 佈不同，使得該第一傳輸線與第二傳輸線中訊號之傳輸 速度不同，以補償因該第二傳輸線與該第一傳輸線長度 不同所產生之傳輸時間差，保證差分訊號同時到達接收 端以維持差分訊號之反相狀態，提高訊號傳輸之品質。 【實施方式】 [0007] 請一併參閱圖1、圖2及圖3，本發明差分訊號線11設置於 一印刷電路板100之布線區域10内，其包括一第一傳輸線 111及一第二傳輸線112，用於傳輸一對差分訊號。該第 098110957 表單編號Α0101 第4頁/共24頁 0982017971-0 201038026 一傳輸線111及第二傳輸線112之長度分別為S1及S2，且 S1<S2 。 [0008] 訊號於傳輸線中之傳輸速度及傳輸時間分別由以下公式 表示： [0009] V =201038026 VI. Description of the Invention: [Technology of the Invention] [0001] The present invention relates to a method for compensating for differential signal lines and differential signal line offsets. [Prior Art] [0002] Generally, the noise of a printed circuit board is a common mode signal. Therefore, the printed circuit board often uses the opposite polarity signal, that is, the differential signal, such as pcb Express, SATA, etc., to realize the signal odd-mode transmission' and uses the differential amplifier to amplify the differential signal at the signal receiving end to filter the common mode noise. . The transmission line of the differential signal generally consists of a pair of transmission lines. Since the motherboard is provided with electronic components of various position requirements, the two transmission lines of the conventional differential signal line cannot be equal in length, so that the differential signals cannot reach the receiving end at the same time and have opposite polarities (as shown in FIGS. 4a and 5a). Ensure that the differential signal arrives at the receiver at the same time and keep the polarity opposite. In the process of differential signal transmission, the transmission line of the differential signal must be the same length. The conventional technique lengthens the length of the shorter side by the delay wiring method to ensure the length of the differential signal line. However, the artificially operated delay wiring method does not make the differential signal transmission line really equal, resulting in a decrease in signal transmission quality (as shown in Figures 4b and 5b). SUMMARY OF THE INVENTION [0003] In view of the above, it is necessary to provide a method for compensating for the difference between the signal line and the differential signal line offset. [0004] A method for compensating a differential signal line offset for compensating for an offset between a first transmission line and a second transmission line in a differential signal line, the compensation method comprising the steps of: calculating a signal at the first Transmission line transmission 098110957 Form nickname A0101 Page 3 / 24 pages 0982017971-0 201038026 Speed; measuring the length of the first transmission line and the second transmission line; calculating the transmission time of the signal on the first transmission line; The transmission time of one transmission line and the second transmission line are equal, and the correspondence relationship between the dielectric constants of the first transmission line and the second transmission line is calculated; and the dielectric constant of the first transmission line or the second transmission line is changed to conform to the correspondence. [0005] A differential signal line includes a first transmission line and a second transmission line. The dielectric constant of the first transmission line is a first dielectric constant, a length is a first length, and a dielectric constant of the second transmission line Is a second dielectric constant, the length is a second length, and satisfies = T~, wherein S1 is the length of the first transmission line, εΐ is the first dielectric constant, and S2 is the length of the second transmission line , ε2 is the second dielectric constant, and C is the speed of light. [0006] Compared with the prior art, the printed circuit board and the compensation method are different in the distribution of the first transmission line and the second transmission line on the first transmission line and the second transmission line, so that the signals in the first transmission line and the second transmission line are different. The transmission speed is different to compensate for the difference in transmission time caused by the difference between the length of the second transmission line and the first transmission line, and the differential signal is simultaneously received at the receiving end to maintain the inverted state of the differential signal, thereby improving the quality of the signal transmission. [0007] Referring to FIG. 1, FIG. 2 and FIG. 3 together, the differential signal line 11 of the present invention is disposed in a wiring area 10 of a printed circuit board 100, and includes a first transmission line 111 and a first The second transmission line 112 is configured to transmit a pair of differential signals. The 098110957 Form No. 1010101 Page 4 of 24 0982017971-0 201038026 The length of one transmission line 111 and the second transmission line 112 are S1 and S2, respectively, and S1<S2. [0008] The transmission speed and transmission time of the signal in the transmission line are respectively expressed by the following formula: [0009] V =
C (1) [0010] Ο [0011] [0012] Ο s .................(2) 其中V表示訊號之傳輸速度，C表示光速，ε表示傳輸線 之介電常數，t表示訊號之傳輸時間，S表示傳輸線之長 度。根據公式（1)及（2)得知，透過改變介電常數ε 可相應地改變傳輸速度V，進而可改變傳輸時間t。 為了保證訊號於該第一傳輸線111及該第二傳輸線112之 傳輸時間tl及t2相等，本實施方式中，該第一傳輸線111 外表面全部塗覆防焊漆30，其介電常數為ε 1，訊號於該 第一傳輸線111之傳輸速度為VI。該第二傳輸線112之外 表面僅局部塗覆防焊漆30，塗覆防焊漆30部分與未塗覆 防焊漆30部分之長度分別占該第二傳輸線112長度S2之百 分比X及y (即x = l-y)，塗覆防焊漆30部分之介電常數 為ε1(與第一傳輸線111之介電常數εΐ相同），未塗覆 防焊漆30部分之介電常數為ε 2，訊號於塗覆防焊漆30部 分之傳輸速度為VI (與訊號於該第一傳輸線111之傳輸速 098110957 表單編號Α0101 第5頁/共24頁 0982017971-0 201038026 度vi相同）），訊號於未塗覆防焊漆3〇部分之傳輪速度 為V2。圖1中3處之剖面圖（如，所示）顯示該第一傳輸 線111及第二傳輸線112之外表面均塗覆防焊漆3〇。圖J 中b處之剖面圖（如圖3所示）顯示僅該第一傳輸線ui之 外表面塗覆防焊漆30。根據公式（1)及（2)，訊號於 邊第一傳輪線111及第二傳輸線1 12之傳輸時間及七2相 等之條件下，可以得出以下公式： [0013]C (1) [0010] [0012] Ο s ........... (2) where V represents the transmission speed of the signal, C represents the speed of light, and ε represents The dielectric constant of the transmission line, t represents the transmission time of the signal, and S represents the length of the transmission line. According to the formulas (1) and (2), the transmission speed V can be changed correspondingly by changing the dielectric constant ε, and the transmission time t can be changed. In the embodiment, the outer surface of the first transmission line 111 is entirely coated with the solder resist 30, and the dielectric constant is ε 1 , in order to ensure that the transmission times t1 and t2 of the first transmission line 111 and the second transmission line 112 are equal. The transmission speed of the signal on the first transmission line 111 is VI. The outer surface of the second transmission line 112 is only partially coated with the solder resist lacquer 30, and the lengths of the portions of the solder resist lacquer 30 and the uncoated solder resist 30 are respectively occupied by the percentages X and y of the length S2 of the second transmission line 112 ( That is, x = ly), the dielectric constant of the portion of the applied solder resist 30 is ε1 (same as the dielectric constant εΐ of the first transmission line 111), and the dielectric constant of the portion of the uncoated solder resist 30 is ε 2 , the signal The transmission speed of the part for applying the solder resist 30 is VI (the same as the transmission speed of the signal on the first transmission line 111 098110957, the form number Α0101, the fifth page, the total of 24 pages 0982017971-0 201038026 degrees vi)), the signal is uncoated The transmission speed of the 3〇 part of the anti-welding paint is V2. The cross-sectional view (shown in Figure 3) of Figure 3 shows that the outer surfaces of the first transmission line 111 and the second transmission line 112 are coated with a solder resist 3 〇. A cross-sectional view at b in Fig. J (shown in Fig. 3) shows that only the outer surface of the first transfer line ui is coated with the solder resist 30. According to the formulas (1) and (2), under the conditions of the transmission time of the first transmission line 111 and the second transmission line 1 12 and the seven-two phase, etc., the following formula can be obtained: [0013]
SbM^S2xx^fE S2xyM ~C^ C~SbM^S2xx^fE S2xyM ~C^ C~
[0014]其中/ S2xx^fe\ ~~C~~ 為訊號於該第二傳輪線112塗覆防焊漆30部分之傳輸時間 7 S2xy^,fe2 〇[0014] wherein / S2xx^fe\~~C~~ is the transmission time of the portion of the second transfer line 112 coated with the solder resist paint 7 S2xy^,fe2 〇
C 為訊號於該第二傳輸線112未塗覆防焊漆30部分之傳輸時 間》 [0015] 請一併參閱圖4a、4b及4c，圖4c中本發明差分訊號線11 傳輸之差分訊號於接收端之相位差為零，差分訊號於接 收端能精確保持反相狀態，其效果明顯好於圖4a習知差 分訊號線及圖4b使用延遲布線法之習知差分訊號線。 098110957 表單編號A0101 第6頁/共24頁 0982017971-0 201038026 刪請-併參閱圖53、圖5b及圖5c，本發明差分訊號線㈣ 輸之差分讯號於接收端之時域眼圖於-〇. 2至-0· 1相對時 間單位（Unit Interval)之區間内之效果明顯好於圖 5a習知差分訊號線及圖5b使用延遲布線法之習知差分訊 - 號線。 [0017] 本實施方式中，本發明差分訊號線Π透過於該第一傳輸 線111之外層全部塗覆防焊漆30減小訊號之傳輸速度以延 長訊號於該第一傳輸線之傳輸時間1:1來使得差分訊號經 0 該第一傳輸線111及第二傳輸線112後同時到達接收端。 其他實施方式中’防焊漆30亦可為其他不同種類之電介 質，於該第一傳輸線111及第二傳輸線W 2之外層局部或 全部塗覆不同種類之電介質亦可達到本發明之目的。另 ，於第二傳輸線112不塗覆電介質之情況下，僅於該第一 傳輸線111局部塗覆電介質亦可達到本發明之目的。 [0018] 請參閱圖6，本發明差分訊號線偏移量之補償方法，用於 補償該第一傳輸線111及第二傳輸線11卩間之偏移量，其 © 較佳實施方式包括以下步驟： [0019] 步驟S61，透過於該第一傳輸線丨11之外層塗覆一防焊漆 30以使得該第一傳輸線111之介電常數為ε 1。 [0020] 步驟S62，測量該第一傳輸線及第二傳輸線112之長 度S1及S2。 [0021]步驟S63 ,根據前述公式（1 )，計算訊號於該第一傳輸 線111之傳輪速度VI。 098110957 步驟S64,根據前述公式（2)，計算訊號於該第一傳輸 表單編號 Α0101 % 7 24 1 0982017971-0 [0022] 201038026 [0023] [0024] 線111之傳輸時間tl。 步驟S65，根據前述公式（3)，計算該第二傳輸線112上 塗覆焊漆30及未塗防焊漆30之長度占第二傳輸線11 2之長 度S2之百分比X及y。 步驟S66，根據該百分比X及y將防焊漆30塗於該第二傳輸 線11 2上。 [0025] 請參閱圖7，本發明差分訊號線偏移量之補償方法，用於 補償該第一傳輸線111及第二傳輸線112間之偏移量，其 另一較佳實施方式包括以下步驟：C is the transmission time of the portion of the second transmission line 112 that is not coated with the solder resist 30. [0015] Please refer to FIGS. 4a, 4b and 4c together, and the differential signal transmitted by the differential signal line 11 of the present invention in FIG. 4c is received. The phase difference of the terminal is zero, and the differential signal can accurately maintain the inverted state at the receiving end, and the effect is obviously better than the conventional differential signal line of FIG. 4a and the conventional differential signal line of the delayed wiring method of FIG. 4b. 098110957 Form No. A0101 Page 6 of 24 0982017971-0 201038026 Delete - and refer to Figure 53, Figure 5b and Figure 5c, the differential signal line of the present invention (4) The differential signal at the receiving end is in the time domain eye diagram - 〇. The effect of the 2 to -0·1 relative time unit (Unit Interval) is significantly better than the conventional differential signal line of Figure 5a and the conventional differential signal line of Figure 5b using the delayed wiring method. [0017] In the embodiment, the differential signal line of the present invention is coated with the solder resist 30 through the outer layer of the first transmission line 111 to reduce the transmission speed of the signal to extend the transmission time of the signal to the first transmission line by 1:1. The differential signal is sent to the receiving end through the first transmission line 111 and the second transmission line 112 at the same time. In other embodiments, the solder resist 30 may be other different types of dielectric materials. It is also possible to apply a different type of dielectric to the outer layers of the first transmission line 111 and the second transmission line W 2 to achieve the object of the present invention. In addition, in the case where the second transmission line 112 is not coated with a dielectric, it is also possible to locally apply the dielectric only to the first transmission line 111. Referring to FIG. 6, a method for compensating a differential signal line offset according to the present invention is used to compensate for the offset between the first transmission line 111 and the second transmission line 11, and the preferred embodiment includes the following steps: [0019] Step S61, applying a solder resist lacquer 30 through the outer layer of the first transmission line 以11 such that the dielectric constant of the first transmission line 111 is ε 1. [0020] Step S62, measuring the lengths S1 and S2 of the first transmission line and the second transmission line 112. [0021] Step S63, calculating the transmission speed VI of the signal on the first transmission line 111 according to the above formula (1). 098110957 Step S64, according to the foregoing formula (2), calculating the signal on the first transmission form number Α0101 % 7 24 1 0982017971-0 [0022] 201038026 [0023] [0024] The transmission time t1 of the line 111. In step S65, according to the foregoing formula (3), the percentages X and y of the length of the coating of the solder resist 30 and the uncoated solder resist 30 on the second transmission line 112 to the length S2 of the second transmission line 11 2 are calculated. In step S66, the solder resist 30 is applied to the second transmission line 11 2 based on the percentages X and y. Referring to FIG. 7, the method for compensating the differential signal line offset of the present invention is used to compensate the offset between the first transmission line 111 and the second transmission line 112. Another preferred embodiment includes the following steps:
[0026] 步驟S71，測量該第一傳輸線111及第二傳輸線112之長 度S1及S2。 [0027] [0028] [0029] 步驟S72,根據前述公式（1)，計算訊號於該第二傳輸 現線112之傳輸速度V2。 步驟S73,根據前述公式（2)，計算訊號於該第二傳輸 線112之傳輸時間t2。 步驟S74,根據前述公式（3)，計算該第一傳輸線111上 塗覆防焊漆30及未塗防焊漆30部分占第一傳輸線111之長 度S1之百分比X及y。 [0030] 步驟S75，根據該長度百分比X及y，將防焊漆30塗於該第 一傳輸線111上。 該差分訊號線11及其偏移量之補償方法透過於該第一傳 輸線111及第二傳輸線112上塗防焊漆30，以改變其介電 常數，使得訊號於該第一傳輸線111與第二傳輸線112之 098110957 表單編號A0101 第8頁/共24頁 0982017971-0 [0031] 201038026 傳輸速度不同，以補償因該第一傳輸線111與第二傳輸線 112長度不同所產生之傳輸時間差，保證差分訊號同時到 達接收端以維持差分訊號之反相狀態’提高訊號傳輸之 品質。 [0032] Ο [0033] [0034] [0035] [0036] [0037] Ο [0038] [0039] [0040] [0041] 098110957 综上所述，本發明符合發明專利要件，爰依法提出專利 申請。惟，以上所述者僅為本發明之較佳實施方式，舉 凡熟悉本案技藝之人士，於要依本發明精神所作之等效 修飾或變化，皆應涵蓋於以下之申請專利範圍内。 【圖式簡單說明】 圖1為本發明差分訊號線之較佳實施方式之示意圖。 圖2為沿圖1中II-II線之剖面圖。 圖3為沿圖1中III-III線之剖面圖。 圖4a為習知差分訊號線傳輸之差分訊號於接收端之相位 差波形圖。 圖4b為使用延遲布線法之習知差分訊號線傳輸之差分訊 號於接收端之相位差波形圖。 圖4c為本發明差分訊號線傳輸之差分訊號於接收端之相 位差波形圖。 圖5a為習知差分訊號線傳輸之差分訊號於接收端之時域 眼圖。 圖5b為使用延遲布線法之習知差分訊號線傳輸之差分訊 號於接收端之時域眼圖。 圖5c為本發明習知差分訊號線傳輪之差分訊號於接收端 表單編號A0101 第9頁/共24頁 0982017971-0 201038026 之時域眼圖。 [0042] [0043] 圖6為本發明差分訊號線偏移量補償方法之較佳實施方式 之流程圖。 圖7為本發明差分訊號線偏移量補償方法之另一較佳實施 方式之流程圖。 【主要元件符號說明】 [0044] 布線區域 10 差分訊號線 11 防焊漆 30 第一傳輸線 111 第二傳輸線 112 印刷電路板 100 098110957 表單編號A0101 第10頁/共24頁 0982017971-0[0026] Step S71, measuring the lengths S1 and S2 of the first transmission line 111 and the second transmission line 112. [0029] Step S72, calculating the transmission speed V2 of the signal on the second transmission line 112 according to the foregoing formula (1). In step S73, the transmission time t2 of the signal on the second transmission line 112 is calculated according to the above formula (2). In step S74, according to the foregoing formula (3), the percentages X and y of the length S1 of the first transmission line 111 coated with the solder resist 30 and the uncoated solder resist 30 are calculated. [0030] Step S75, applying the solder resist 30 to the first transmission line 111 according to the length percentages X and y. The differential signal line 11 and the offset compensation method thereof are coated with the solder resist 30 on the first transmission line 111 and the second transmission line 112 to change the dielectric constant thereof so that the signal is on the first transmission line 111 and the second transmission line. 112 098110957 Form No. A0101 Page 8 / Total 24 Page 0982017971-0 [0031] 201038026 The transmission speed is different to compensate for the difference in transmission time due to the different lengths of the first transmission line 111 and the second transmission line 112, and to ensure that the differential signals arrive at the same time. The receiving end maintains the inverted state of the differential signal to improve the quality of the signal transmission. [0030] [0034] [0034] [0037] [0037] [0037] [0040] [0040] [0041] 098110957 In summary, the present invention meets the requirements of the invention patent, and patent application is filed according to law. . However, the above-mentioned embodiments are only the preferred embodiments of the present invention, and those skilled in the art will be able to make modifications and variations equivalent to the spirit of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of a preferred embodiment of a differential signal line of the present invention. Figure 2 is a cross-sectional view taken along line II-II of Figure 1. Figure 3 is a cross-sectional view taken along line III-III of Figure 1. Fig. 4a is a waveform diagram showing the phase difference of the differential signal transmitted by the conventional differential signal line at the receiving end. Fig. 4b is a waveform diagram showing the phase difference of the differential signal transmitted by the conventional differential signal line using the delay wiring method at the receiving end. Fig. 4c is a waveform diagram showing the phase difference of the differential signal transmitted by the differential signal line at the receiving end according to the present invention. Fig. 5a is a time-domain diagram of a differential signal transmitted by a conventional differential signal line at a receiving end. Fig. 5b is a time-domain diagram of the differential signal transmitted by the conventional differential signal line using the delay wiring method at the receiving end. Fig. 5c is a time-domain diagram of a conventional differential signal line transmission differential signal at the receiving end, Form No. A0101, page 9 of 24, 0982017971-0 201038026. [0043] FIG. 6 is a flow chart of a preferred embodiment of a differential signal line offset compensation method according to the present invention. FIG. 7 is a flow chart of another preferred embodiment of a differential signal line offset compensation method according to the present invention. [Main component symbol description] [0044] Wiring area 10 Differential signal line 11 Solder resist paint 30 First transfer line 111 Second transfer line 112 Printed circuit board 100 098110957 Form No. A0101 Page 10 of 24 0982017971-0