JPH07128379A - Inspection method for printed wiring board - Google Patents
Inspection method for printed wiring boardInfo
- Publication number
- JPH07128379A JPH07128379A JP30346593A JP30346593A JPH07128379A JP H07128379 A JPH07128379 A JP H07128379A JP 30346593 A JP30346593 A JP 30346593A JP 30346593 A JP30346593 A JP 30346593A JP H07128379 A JPH07128379 A JP H07128379A
- Authority
- JP
- Japan
- Prior art keywords
- conductor
- wiring conductor
- characteristic impedance
- wiring
- resistance
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Measurement Of Resistance Or Impedance (AREA)
- Structure Of Printed Boards (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明はプリント配線板の特性イ
ンピ−ダンスの合否を判定する検査方法に関するもので
ある。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection method for determining whether a characteristic impedance of a printed wiring board is acceptable or not.
【０００２】[0002]
【従来の技術】電子機器、例えば、コンピュ−タ、ファ
クシミリ、電子交換機、各種計測機、制御機器、軍需用
等の産業用機器の配線に使用されているプリント配線板
においては、例えば、銅張積層板等の積層基材の導体材
（銅箔）を光学的な印刷配線技術により所定の配線パタ
−ンに形成することにより製造されている。2. Description of the Related Art In printed wiring boards used for wiring electronic equipment such as computers, facsimiles, electronic exchanges, various measuring machines, control equipment, and industrial equipment such as military equipment, copper-clad boards are used. It is manufactured by forming a conductor material (copper foil) of a laminated base material such as a laminated plate into a predetermined wiring pattern by an optical printed wiring technique.
【０００３】このプリント配線板の電気特性の一つとし
て特性インピ−ダンスがあり、配線導体の特性インピ−
ダンスのバラツキは実装デバイスの誤動作の原因となる
ことがある。例えば、配線導体の特性インピ−ダンスが
デバイスの出力インピ−ダンスに較べて相当に低い場
合、デバイスの出力レベルが最終値に達するまでに多重
反射が発生し、デバイスの実効スイッチング速度が遅延
され、この遅れたスイッチングの間に過渡電流やサ−ジ
電流が駆動デバイスからラインに流入し、ラインの誤動
作が招来されることがある。従って、プリント配線板の
製造における最終段階で特性インピ−ダンスの合否を判
定することが要求される。There is a characteristic impedance as one of the electrical characteristics of this printed wiring board, which is a characteristic impedance of a wiring conductor.
Variations in dance may cause malfunction of mounted devices. For example, if the characteristic impedance of the wiring conductor is significantly lower than the output impedance of the device, multiple reflections will occur before the output level of the device reaches its final value, delaying the effective switching speed of the device, During this delayed switching, a transient current or a surge current may flow into the line from the driving device, causing a malfunction of the line. Therefore, it is required to determine the pass / fail of the characteristic impedance at the final stage of manufacturing the printed wiring board.
【０００４】而して、従来、プリント配線板の特性イン
ピ−ダンスの測定方法としては、 プリント配線板が実質上、無損失回路であり、特性イ
ンピ−ダンスＺ0が Ｚ0＝√Ｌ／√Ｃ で与えられることから（ただし、Ｌは配線導体のインダ
クタンス、Ｃは配線パタ−ンと接地面との間のキャパシ
タンス）、Ｌ並びにＣをそれぞれ測定し、これらから特
性インピ−ダンスＺ0を測定する方法。 タイムドメインリフレクトメトリにより特性インピ−
ダンスを直接測定する方法。 プリント配線板に配線導体とは電気的に独立の検査用
配線導体を形成し、この検査用配線導体の特性インピ−
ダンスを上記またはの方法により測定する方法等が
公知である。As a conventional method for measuring the characteristic impedance of a printed wiring board, the printed wiring board is a virtually lossless circuit, and the characteristic impedance Z 0 is Z 0 = √L / √ Since it is given by C (where L is the inductance of the wiring conductor, C is the capacitance between the wiring pattern and the ground plane), L and C are measured, respectively, and the characteristic impedance Z 0 is measured from them. how to. Characteristic Impedance by Time Domain Reflectometry
How to measure dance directly. An inspection wiring conductor electrically independent of the wiring conductor is formed on the printed wiring board, and the characteristic impedance of the inspection wiring conductor is formed.
A method of measuring the dance by the above method or the like is known.
【０００５】[0005]
【発明が解決しようとする課題】しかしながら、上記
の方法では、インダクタンスの測定のために配線導体の
遠端を短絡し、測定後はその短絡を開放する必要があ
り、この短絡・開放処理にかなりの時間を要し、作業性
に劣る、その処理の仕方如何によっては配線導体遠端が
破損される等の不利がある。また、使用周波数帯域で
Ｌ、Ｃを測定する必要があり、リ−ドケ−ブルやプロ−
ブ等に付加されるインダクタンス分やキャパシタンス分
による測定誤差も問題である。However, in the above method, it is necessary to short-circuit the far end of the wiring conductor for measuring the inductance and open the short-circuit after the measurement. However, there is a disadvantage in that the workability is poor, the far end of the wiring conductor is damaged, etc. depending on the processing method. In addition, it is necessary to measure L and C in the frequency band used, and it is necessary to measure the lead cable and the program.
There is also a problem of measurement error due to inductance and capacitance added to the cable.
【０００６】上記の方法では、測定波の立上りが超高
速であり、プロ−ブ接触点で反射が発生することのない
ように、その接触状態を微妙に調整する必要があり、プ
ロ−ビングに熟練を必要とする、また、多点同時測定が
難しい等の不利がある。In the above method, the rising of the measurement wave is very fast, and it is necessary to finely adjust the contact state so that reflection does not occur at the probe contact point. There are disadvantages such as requiring skill and difficulty in simultaneous measurement at multiple points.
【０００７】上記の方法では、上記の方法における
配線導体の遠端損傷の畏れは解消できるが、検査用配線
導体を設けるための専用のスペ−スが必要となり、プリ
ント配線板の大型化が避けられないし、更に、配線導体
の遠端損傷以外のの方法の不利、並びにの方法の不
利が依然として存在している。The above method can eliminate the fear of damage to the far end of the wiring conductor in the above method, but requires a dedicated space for providing the wiring conductor for inspection, and avoids an increase in the size of the printed wiring board. Moreover, there are still disadvantages of the method other than the far-end damage of the wiring conductors, as well as the disadvantages of the method.
【０００８】上記プリント配線板の基材である積層基
材、例えば銅張積層板の製造の最終段階において、導体
材の厚み並びに絶縁材の厚みが検査され、上記特性イン
ピ−ダンスを測定すべきプリント配線板の配線導体の厚
み並びに絶縁材の厚みは既知である。At the final stage of manufacturing a laminated base material which is a base material of the printed wiring board, for example, a copper clad laminated board, the thickness of the conductor material and the thickness of the insulating material should be inspected to measure the characteristic impedance. The thickness of the wiring conductor and the thickness of the insulating material of the printed wiring board are known.
【０００９】本発明の目的は、プリント配線板の製造に
おいて、プリント配線板の絶縁材の厚み並びに配線導体
の厚みが既知であることを勘案し、リ−ドケ−ブルやプ
ロ−ブの影響を受けることなく、しかも容易に、低廉な
測定装置で配線導体の特性インピ−ダンスの合否を判定
できるプリント配線板の検査方法を提供することにあ
る。In view of the fact that the thickness of the insulating material of the printed wiring board and the thickness of the wiring conductor are known in the production of the printed wiring board, the object of the present invention is to reduce the influence of lead cables and probes. It is an object of the present invention to provide a method for inspecting a printed wiring board, which can easily determine the pass / fail of the characteristic impedance of a wiring conductor with a low-cost measuring device without receiving it.
【００１０】[0010]
【課題を解決するための手段】本発明のプリント配線板
の検査方法は、導体材厚み並びに絶縁材厚みが既知の積
層基材の導体材を所定の配線パタ−ンに形成したのち、
その配線導体の直流抵抗を測定して配線導体の導体巾を
求め、この導体巾から特性インピ−ダンスの合否を判定
することを特徴とする構成である。According to a method of inspecting a printed wiring board of the present invention, after a conductor material of a laminated base material having a known conductor material thickness and an insulating material thickness is formed in a predetermined wiring pattern,
The DC resistance of the wiring conductor is measured to obtain the conductor width of the wiring conductor, and the pass / fail of the characteristic impedance is determined from this conductor width.
【００１１】[0011]
【作用】プリント配線板の配線導体の特性インピ−ダン
スは、配線導体の巾Ｗと絶縁材の厚みＨ（配線導体と接
地面導体または電源面導体との間隔）と絶縁材の誘電率
とから与えられるが、誘電率が既知であり、Ｈが既知の
一定値であるから、Ｗのみの函数となる。The characteristic impedance of the wiring conductor of the printed wiring board is determined by the width W of the wiring conductor, the thickness H of the insulating material (the distance between the wiring conductor and the ground plane conductor or the power plane conductor), and the dielectric constant of the insulating material. Given that the permittivity is known and H is a known constant value, it is a function of only W.
【００１２】而るに、配線導体の既知の長さ部分の直流
抵抗は、配線導体の導電率と配線導体の厚みｔと巾とか
ら与えられるが、導電率が既知であり、厚みｔが既知の
一定値であるから、Ｗのみの函数となる。The DC resistance of the known length portion of the wiring conductor is given by the conductivity of the wiring conductor and the thickness t and width of the wiring conductor. The conductivity is known and the thickness t is known. Since W is a constant value, only W is a function.
【００１３】従って、配線導体の特性インピ−ダンスが
配線導体の直流抵抗のみの函数となり、その直流抵抗の
測定値から特性インピ−ダンスを求め、正規の特性イン
ピ−ダンス値との比較により合否を判定できる。Therefore, the characteristic impedance of the wiring conductor becomes a function of only the DC resistance of the wiring conductor, the characteristic impedance is obtained from the measured value of the DC resistance, and the pass / fail result is determined by comparison with the normal characteristic impedance value. You can judge.
【００１４】[0014]
【実施例】以下、図面を参照しつつ本発明の実施例を説
明する。図１は本発明の実施例を示す説明図である。図
１において、１はプリント配線板を示し、導体材厚み並
びに絶縁材厚みが既知の配線パタ−ンの導体材を所定の
配線パタ−ンに形成してある（図示の例では、説明を簡
易にするために、直線状としてある）。１１は接地面導
体または電源面導体を、１２は絶縁材を、１３は配線導
体をそれぞれ示している。Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view showing an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a printed wiring board, in which a conductor material having a known conductor pattern thickness and insulating material thickness is formed in a predetermined wiring pattern (in the illustrated example, the explanation is simplified. In order to make it straight.) Reference numeral 11 is a ground plane conductor or power plane conductor, 12 is an insulating material, and 13 is a wiring conductor.
【００１５】２は直流抵抗測定装置を示し、配線導体１
３にプロ−ブ２１１，２１２を介して直流電流を通電す
る定電流源２１と、プロ−ブ２１１，２１２と配線導体
１３との接触点よりも内側において配線導体１３の二点
間の電位差をプロ−ブ２２１，２２２を介して測定する
電位差計２２とから構成されている。Reference numeral 2 denotes a DC resistance measuring device, which is a wiring conductor 1.
3 is a constant current source 21 for passing a direct current through the probes 211 and 212, and a potential difference between two points of the wiring conductor 13 inside the contact point between the probes 211 and 212 and the wiring conductor 13. It is composed of a potentiometer 22 which measures through the probes 221 and 222.
【００１６】上記プリント配線板の配線導体の特性イン
ピ−ダンスは、配線導体の導体巾をＷ、配線導体と接地
面導体または電源面導体との間の間隔（絶縁材の厚み）
をＨ、絶縁材の誘電率をεとすれば、Ｗ≦Ｈの場合、次
式の、、式で与えられ、The characteristic impedance of the wiring conductor of the printed wiring board is such that the conductor width of the wiring conductor is W, the distance between the wiring conductor and the ground plane conductor or the power plane conductor (thickness of the insulating material).
Where H is H and the dielectric constant of the insulating material is ε, when W ≦ H, given by
【００１７】[0017]
【数１】 Ｗ≧Ｈの場合、次式の’、’、’式で与えられ
る。[Equation 1] When W ≧ H, it is given by the following equations', ','.
【００１８】[0018]
【数２】 [Equation 2]
【００１９】而るに、絶縁材の材質から誘電率εは既知
であり、また、絶縁材の厚みＨは配線パタ−ンの製造工
程においてその厚みが管理されており、既知の一定値で
あるから、上記の特性インピ−ダンスＺ0は配線導体の
導体巾Ｗのみの函数となる。上記において、電位差計の
プロ−ブ間の距離をＬ、配線導体の導電率をδ、配線導
体の厚みをｔ、電位差計の指示値をＶ、通電電流をＩと
すると、電位差計のフロ−ブ間の配線導体の直流抵抗値
Ｒ0は、Therefore, the dielectric constant ε is known from the material of the insulating material, and the thickness H of the insulating material is a known constant value because the thickness is controlled in the manufacturing process of the wiring pattern. Therefore, the above characteristic impedance Z 0 is a function of only the conductor width W of the wiring conductor. In the above, if the distance between the probes of the potentiometer is L, the conductivity of the wiring conductor is δ, the thickness of the wiring conductor is t, the indicated value of the potentiometer is V, and the energizing current is I, the flow of the potentiometer is shown. DC resistance R 0 of the wiring conductor between the
【００２０】 Ｒ0＝Ｌ／（Ｗｔδ）＝Ｖ／Ｉ で与えられ、従って、 Ｗ＝Ｌ／（Ｒ0ｔδ） が成立する。R 0 = L / (Wt δ) = V / I, and therefore W = L / (R 0 t δ) holds.
【００２１】而るに、導体材の材質から導電率は既知で
あり、また、導体材の厚み（配線導体の厚み）ｔは配線
パタ−ンの製造工程において、その厚みが管理されてお
り、既知の一定値であり、更に電位差計のフロ−ブ間の
距離Ｌも知ることができるから、上記配線導体の導体巾
Ｗは配線導体の直流抵抗値Ｒ0のみの函数となる。従っ
て、配線導体の特性インピ−ダンスＺ0を配線導体の直
流抵抗値Ｒ0のみの函数として表すことができる。即
ち、 Ｚ0＝Ｇ（Ｒ0）＝Ｇ（Ｖ／Ｉ） で表すことができる。Therefore, the conductivity is known from the material of the conductor material, and the thickness t of the conductor material (thickness of the wiring conductor) is controlled in the manufacturing process of the wiring pattern. Since it is a known constant value and the distance L between the probes of the potentiometer can be known, the conductor width W of the wiring conductor is a function of only the DC resistance value R 0 of the wiring conductor. Therefore, the characteristic impedance Z 0 of the wiring conductor can be expressed as a function of only the DC resistance value R 0 of the wiring conductor. That is, it can be expressed by Z 0 = G (R 0 ) = G (V / I).
【００２２】本発明において、プリント配線板の配線導
体の特性インピ−ダンスを測定するには、上記の定電流
源のプロ−ブ間の間隔並びに電位差計のプロ−ブ間の間
隔を一定の間隔に固定し、測定装置を配線導体上に沿い
移動させて多点において、上記Ｒ0を測定し、式より
特性インピ−ダンスＺ0を求め、その平均値をプリント
配線板の特性インピ−ダンスとすることができる。In the present invention, in order to measure the characteristic impedance of the wiring conductor of the printed wiring board, the intervals between the probes of the constant current source and the intervals between the probes of the potentiometer are set to be constant intervals. The measurement device is fixed along the line conductor and the measurement device is moved along the wiring conductor to measure the above R 0 at multiple points, the characteristic impedance Z 0 is obtained from the formula, and the average value thereof is taken as the characteristic impedance of the printed wiring board. can do.
【００２３】また、片側のプロ−ブを固定とし、他側の
プロ−ブをリ−ドケ−ブルにより可動とし、配線導体の
近端とデバイス設置点とに各プロ−ブを接触させて、ま
たは、デバイス設置点と配線導体の遠端とに各プロ−ブ
を接触させて上記Ｒ0を測定し、式より特性インピ−
ダンスＺ0を求め、これをプリント配線板の特性インピ
−ダンスとすることもできる。Further, the probe on one side is fixed, the probe on the other side is movable by a lead cable, and each probe is brought into contact with the near end of the wiring conductor and the device installation point. Alternatively, each probe is brought into contact with the device installation point and the far end of the wiring conductor, and the above R 0 is measured.
It is also possible to obtain the dance Z 0 and use it as the characteristic impedance of the printed wiring board.
【００２４】上記何れの場合においても、電位差計の表
示を上記式に基づく特性インピ−ダンスの表示として
おけば、特性インピ−ダンスＺ0を直読でき便利であ
る。本発明は、プリント配線板の製造工程の最終段階で
の検査に使用され、検査ステ−ジに次々に搬入されてく
るプリント配線板の配線導体の特性インピ−ダンスを上
記した方法により測定し、この測定値と特性インピ−ダ
ンスの設計値とを比較し、所定差ｘを基準として特性イ
ンピ−ダンスの合否を判定する。この場合、上記配線パ
タ−ンの絶縁材の厚みＨの許容誤差に基づく特性インピ
−ダンスの誤差をａ1、導体材厚みｔの許容誤差に基づ
く特性インピ−ダンスの誤差をａ2とし、特性インピ−
ダンスの許容誤差をΔＺ0とすれば、ｘ＝ΔＺ0−（ａ1
＋ａ2）とされる。In any of the above cases, if the display of the potentiometer is the display of the characteristic impedance based on the above equation, the characteristic impedance Z 0 can be directly read, which is convenient. The present invention is used for the inspection at the final stage of the manufacturing process of the printed wiring board, and the characteristic impedance of the wiring conductors of the printed wiring board which are successively carried into the inspection stage is measured by the method described above, This measured value is compared with the design value of the characteristic impedance, and the pass / fail of the characteristic impedance is determined based on the predetermined difference x. In this case, the characteristic impedance error based on the tolerance of the thickness H of the insulating material of the wiring pattern is a 1 and the characteristic impedance error based on the tolerance of the conductor thickness t is a 2 , and the characteristic is Impey
If the dance tolerance is ΔZ 0 , x = ΔZ 0 − (a 1
+ A 2 ).
【００２５】本発明において、配線導体の抵抗測定に
は、上記以外の公知の方法を使用でき、特に、プロ−ブ
の接触抵抗の影響を除去した抵抗測定法を使用すること
が望ましい。例えば、４端子抵抗法、電位差計法、ホイ
−トストンブケッジ法、ケルビンダブルブリッジ法等を
使用することが好ましい。In the present invention, known methods other than the above can be used for measuring the resistance of the wiring conductor, and it is particularly preferable to use the resistance measuring method in which the influence of the contact resistance of the probe is removed. For example, it is preferable to use a 4-terminal resistance method, a potentiometer method, a Wheatstone bucket method, a Kelvin double bridge method, or the like.
【００２６】なお、本発明においては、測定装置をコン
ピュ−タ制御することにより、プリント配線板の特性イ
ンピ−ダンスの検査を自動化することが可能である。ま
た、スキャ−ナを用いて多数の配線導体を同時に検査す
ることも可能である。In the present invention, the inspection of the characteristic impedance of the printed wiring board can be automated by computer-controlling the measuring device. It is also possible to simultaneously inspect a large number of wiring conductors using a scanner.
【００２７】[0027]
【発明の効果】本発明のプリント配線板の検査方法は、
上述した通りの構成であり、配線導体の直流抵抗値から
特性インピ−ダンスを求めているから、使用周波数帯域
でのインダクタンス、並びにキャパシタンスから特性イ
ンピ−ダンスを求める場合とは異なり、付加インダクタ
ンスやキャパシタンスの影響を受けることがなく、また
遠端での短絡・開放の面倒を排除できる。更に、タイム
ドメインリフレクトメトリによる場合とは異なり、プロ
−ビングが容易であり、しかも、測定装置が低廉であ
る。従って、本発明によれば、プリント配線板の配線導
体の特性インピ−ダンスを容易に、且つ低コストで検査
することができる。The method for inspecting a printed wiring board according to the present invention comprises:
Since the characteristic impedance is obtained from the DC resistance value of the wiring conductor as described above, different from the case where the characteristic impedance is obtained from the inductance and capacitance in the operating frequency band, the additional inductance and capacitance are different. It is not affected by, and the trouble of short circuit and opening at the far end can be eliminated. Further, unlike the case of using time domain reflectometry, probing is easy and the measuring device is inexpensive. Therefore, according to the present invention, the characteristic impedance of the wiring conductor of the printed wiring board can be easily inspected at low cost.
【図１】本発明の実施例を示す説明図である。FIG. 1 is an explanatory diagram showing an embodiment of the present invention.
１ プリント配線板 １１ 接地面導体 １２ 絶縁材 １３ 配線導体 ２ 直流抵抗測定装置 1 Printed wiring board 11 Ground plane conductor 12 Insulation material 13 Wiring conductor 2 DC resistance measuring device
Claims (1)
基材の導体材を所定の配線パタ−ンに形成したのち、そ
の配線導体の直流抵抗を測定して配線導体の導体巾を求
め、この導体巾から特性インピ−ダンスの合否を判定す
ることを特徴とするプリント配線板の検査方法。1. A conductor width of a wiring conductor is obtained by forming a conductor material of a laminated base material having a known conductor thickness and an insulating material thickness on a predetermined wiring pattern and then measuring the DC resistance of the wiring conductor. A method for inspecting a printed wiring board, which is characterized by determining whether the characteristic impedance is acceptable or not based on the conductor width.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30346593A JPH07128379A (en) | 1993-11-08 | 1993-11-08 | Inspection method for printed wiring board |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30346593A JPH07128379A (en) | 1993-11-08 | 1993-11-08 | Inspection method for printed wiring board |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH07128379A true JPH07128379A (en) | 1995-05-19 |
Family
ID=17921297
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP30346593A Pending JPH07128379A (en) | 1993-11-08 | 1993-11-08 | Inspection method for printed wiring board |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07128379A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103336178A (en) * | 2013-06-05 | 2013-10-02 | 浙江华电器材检测研究所 | A conductor direct current resistance intelligent testing system and a method thereof |
| CN104619114A (en) * | 2015-02-15 | 2015-05-13 | 歌尔声学股份有限公司 | PCB (printed circuit board) with embedded resistors and embedded resistor test method |
-
1993
- 1993-11-08 JP JP30346593A patent/JPH07128379A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103336178A (en) * | 2013-06-05 | 2013-10-02 | 浙江华电器材检测研究所 | A conductor direct current resistance intelligent testing system and a method thereof |
| CN104619114A (en) * | 2015-02-15 | 2015-05-13 | 歌尔声学股份有限公司 | PCB (printed circuit board) with embedded resistors and embedded resistor test method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5424633A (en) | Contactless test method and system for testing printed circuit boards | |
| US20010008377A1 (en) | Non-contact board inspection probe | |
| US20110260743A1 (en) | Contactless measuring system | |
| JP2002055126A (en) | Non-contact type voltage measuring method and device therefor | |
| JP2008046038A (en) | Disconnection test method of coaxial cable assembly | |
| US6798212B2 (en) | Time domain reflectometer probe having a built-in reference ground point | |
| JPH07128379A (en) | Inspection method for printed wiring board | |
| TW201522980A (en) | Probe module (II) | |
| CN216696462U (en) | Contact current measuring tool | |
| KR100930989B1 (en) | Apparatus of inspecting electric condition, and method of manufacturing the same | |
| JP2019056578A (en) | Circuit board inspection device | |
| EP2930523B1 (en) | Contactless conductive interconnect testing | |
| US20120098554A1 (en) | Method and device for measuring permittivity and/or permeability | |
| JP4066478B2 (en) | Method and apparatus for measuring common mode impedance of electronic circuit board | |
| Paulter | A fast and accurate method for measuring the dielectric constant of printed wiring board materials | |
| KR100472918B1 (en) | Method for testing branch line and pdp electrode using frequency response | |
| JP6855634B1 (en) | Inspection method and inspection system | |
| US6293817B1 (en) | Extended length, high frequency contactor block | |
| JPH0339989A (en) | Method for inspecting defect of transparent conductive circuit substrate | |
| JP4467027B2 (en) | Electrical circuit disconnection inspection method | |
| TWI779747B (en) | Inspection method and inspection device | |
| JP2002286786A (en) | Impedance measuring circuit pattern and impedance measuring circuit board | |
| KR100193758B1 (en) | Inductance and capacitance measurement device of lumped element using vector network analyzer and its method | |
| JP4369002B2 (en) | Circuit board inspection equipment | |
| JP2000314755A (en) | Neighborhood electromagnetic field detecting probe system |