KR20230063830A - Impedance change position detection device and method - Google Patents

Abstract

An impedance change position detection apparatus according to an embodiment of the present invention includes: a reference wire selecting unit that selects a plurality of reference wires from among a plurality of wires of a substrate, and the plurality of reference wires includes a plurality of sections; a total reflection time measuring unit extracting wire lengths for each section of the plurality of reference wires and measuring a total reflection time for each of the plurality of reference wires; a section-by-section propagation speed obtainer for obtaining a propagation speed at each section using the wire length for each section and the total reflection time; and an impedance displacement position detection unit for detecting a position of impedance change using the propagation speed for each section. includes

Description

Impedance change position detection device and method {IMPEDANCE CHANGE POSITION DETECTION DEVICE AND METHOD}

The present invention relates to an impedance change location detection device and an impedance change location detection method.

In general, along with the miniaturization and high functionality of electronic devices, 3D (3 Dimensions), multi-layer, and miniaturization technologies of board mounting are in progress. TDR (Time Domain Reflectometry), which can identify the state and position of wiring impedance change in the electronic circuit board, which is becoming more complex, is necessary for circuit design development and abnormal position analysis.

This TDR is a method of analyzing the distance from the probing position by measuring the reflection time of the step voltage signal, but has a disadvantage in that it is difficult to apply to the analysis of high-density board wiring due to the limited time resolution of the step signal.

In contrast, spike signal reflection type TDR analysis using Tera Hz technology is attracting attention as a high time resolution TDR method.

A high time resolution TDR using the existing Tera Hz technology has a high accuracy time resolution of the femto second level and can interpret the impedance change location by converting this time information into location information.

However, the high temporal resolution TDR using the existing Tera Hz technology has a problem in that high accuracy temporal resolution is not utilized due to low accuracy when converting reflection time information into distance.

On the other hand, Japanese Laid-Open Patent Publication No. 1997-026376 (name: OTDR measuring device) transmits a spike voltage signal generated from laser light to an electronic circuit to measure the time of the reflected signal reflected at the impedance change position in the electronic circuit by femto ) technology for determining the location of an anomaly by detecting it at the level of seconds.

In the above patent document (Japanese Laid-Open Patent Publication No. 1997-026376), the determination of the abnormal position is the round-trip time from the input input position to the reflection and return from the abnormal position T, and the distance from the input position to the abnormal position D , it is interpreted by expecting that D=V*T holds.

However, this method has a problem that the positioning accuracy is not accurate. This is because the transmission speed of each layer constituting the circuit wiring is different, and the transmission speed of the interlayer vias of the board is also different due to the difference in shape.

(Prior art literature)

(Patent Document 1) KR Patent Publication No. 10-2013-0005658 (published date: 2013.01.16)

(Patent Document 1) JP Patent Publication No. 2010-019865 (published date: 2010.01.28)

An embodiment of the present invention derives the radio signal transmission rate for each section of the reference wiring using the reflected waveform results of several reference wires and the time and distance for each section of the reference wiring, and acquires the TDR waveform of the wiring to be measured We propose an impedance change position detection device and method capable of detecting the impedance change position with higher position resolution by reflecting the propagation speed for each structure.

According to an embodiment of the present invention, a reference wire selection unit for selecting a plurality of reference wires from among a plurality of wires of a substrate, wherein the plurality of reference wires includes a plurality of sections; a total reflection time measurement unit extracting wire lengths for each section of the plurality of reference wires and measuring a total reflection time for each of the plurality of reference wires; a section-by-section propagation speed obtainer for obtaining a propagation speed at each section using the wire length for each section and the total reflection time; and an impedance displacement position detection unit for detecting a position of impedance change using the propagation speed for each section. An impedance change position detection device including a is proposed.

In addition, according to another embodiment of the present invention, a first step of selecting a plurality of reference wires from among a plurality of wires of a substrate, wherein the plurality of reference wires include a plurality of sections; a second step of extracting wire lengths for each section of the plurality of reference wires and measuring a total reflection time for each of the plurality of reference wires; a third step of obtaining a propagation speed for each section using the wire length for each section and the total reflection time; and a fourth step of detecting a position of impedance change using the propagation speed for each section. An impedance change position detection method including a is proposed.

According to an embodiment of the present invention, the radio signal transmission speed for each section of the reference wiring is derived using the reflected waveform results of several reference wirings and the time and distance for each section of the reference wiring, and the TDR waveform of the wiring to be measured is obtained. Therefore, by reflecting the propagation speed for each structure, it is possible to detect the position of the impedance change with a more accurate position resolution.

In other words, according to the present invention, it is possible to accurately analyze the change position of impedance, for example, there are detailed advantages as follows.

- Accurately analyzes the location of disconnection and short-circuiting of wiring.

- Impedance matching and unmatching analysis for each part of the electronic device is realized with high accuracy

- High-accuracy analysis of radio wave signal speed by section on high-speed circuit boards, etc.

- Realization of effective permittivity analysis for each part of electronic devices with high accuracy

- Analysis of transmission characteristics for each part of wiring is realized with high accuracy

- Analysis of effective permittivity, impedance, and propagation speed for each section is realized only by actual device measurement without special dedicated experiments such as test coupons

1 is an exemplary view of an impedance change position detection device according to an embodiment of the present invention.
2 is an exemplary view of a method for detecting a location of an impedance change according to an embodiment of the present invention.
3 is an exemplary view of a reference wiring of a board according to an embodiment of the present invention.
4 is an exemplary view of reflection time of a reference line.
5 is an exemplary TDR waveform showing propagation time for each section.
6 is an exemplary view of a TDR waveform of a normal wiring and a TDR waveform of a defective wiring showing propagation time for each section.

Hereinafter, it should be understood that the present invention is not limited to the described embodiments, and various changes can be made without departing from the spirit and scope of the present invention.

In addition, in each embodiment of the present invention, the structure, shape, and numerical value described as an example are only examples to help the understanding of the technical details of the present invention, so they are not limited thereto, but the spirit and scope of the present invention It should be understood that various changes can be made without departing from it. Embodiments of the present invention can be combined with each other to make various new embodiments.

In addition, in the drawings referred to in the present invention, elements having substantially the same configuration and function in light of the overall content of the present invention will use the same reference numerals.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily practice the present invention.

1 is an exemplary view of an impedance change position detection device according to an embodiment of the present invention.

Referring to FIG. 1 , an impedance change location detection apparatus 100 according to an embodiment of the present invention includes a reference wiring selection unit 110, a total reflection time measurement unit 120, and a propagation speed acquisition unit 130 for each section. and an impedance displacement position detection unit 140 .

The reference wire selector 110 selects a plurality of reference wires from among a plurality of wires of the substrate, and the plurality of reference wires may include a plurality of sections. For example, the plurality of reference wires may include the plurality of sections in which different propagation velocities are mixed.

The total reflection time measurement unit 120 extracts wire lengths (dLY1, dvia, dLY7) for each section of the plurality of reference wires, and calculates total reflection times (t1total, t2total, and t3total) for each of the plurality of reference wires. can be measured

For example, the total reflection time measurement unit 120 extracts the wire lengths dLY1, dvia, and dLY7 for each section of the plurality of reference wires based on distance data stored in the memory unit 150, and , the total reflection time (t1total, t2total, t3total) for each of the plurality of reference wires may be measured.

For example, the total reflection time measuring unit 120 may obtain a TDR waveform for each of the plurality of reference wires, and obtain the total reflection time (t1total, t2total, t3total) based on the TDR waveform.

The section-by-section propagation velocity acquisition unit 130 uses the section-by-section wire lengths (dLY1, dvia, dLY7) of the plurality of reference wires and the total reflection time (t1total, t2total, t3total) to section-by-section propagation speed (VLY1, Vvia, VLY7) can be obtained.

Here, VLY1 can be obtained as dLY1/tLY1, VLY7 can be obtained as dLY7/tLY7, and Vvia can be obtained as dvia/tvia.

For example, the propagation velocity acquisition unit 130 for each section of the plurality of reference wires uses the wire lengths dLY1, dvia, and dLY7 for each section and the total reflection time t1total, t2total, and t3total to obtain the plurality of reference wires. The propagation times (tLY1,tvia,tLY7) of the reference wiring for each section are obtained, and the wire lengths (dLY1,dvia,dLY7) for each section and the propagation time for each section (tLY1,tvia,tLY7) are used for each section. Propagation velocities (VLY1, Vvia, VLY7) can be obtained.

The section-by-section propagation speed acquisition unit 130 includes the section-by-section wiring lengths (dLY1, dvia, dLY7) and the total reflection time (t1total, t2total, t3total) as matrix parameters for the plurality of reference wirings. By solving a matrix equation, propagation times (tLY1,tvia,tLY7) for each section of the plurality of reference lines can be obtained.

For example, the propagation speed acquisition unit 130 for each section uses the wire lengths dLY1, dvia, and dLY7 for each section and the total reflection time t1total, t2total, and t3total for the plurality of reference wires as matrix parameters. Propagation times (tLY1,tvia,tLY7) for each section of the plurality of reference wires can be obtained by solving the following matrix equation including , and this matrix equation will be described later.

Also, the impedance displacement position detection unit 140 may detect the impedance change position using the propagation velocities VLY1, Vvia, and VLY7 for each section.

For example, the impedance displacement position detector 140 may detect the impedance change position based on the propagation speeds VLY1, Vvia, and VLY7 for each section and the propagation time for each section tLY1,tvia, and tLY7. there is.

In addition, when the inspection signal is generated (101), a inspection signal to be provided to the reference wiring of the substrate 20 to be inspected may be generated and provided to the substrate 20.

The signal detector 102 may detect a test signal (eg, a TDR waveform signal) at a probe point of each of a plurality of reference wires of the substrate 20 .

The memory unit 150 has different structural wiring lengths (dL1-LY1, dvia, dL1-LY7) (dL2-LY1, dvia, dL2-LY7) ( dL3- Design data for LY1, dvia, dL3-LY7) can be saved.

Hereinafter, a more detailed description of the reference wire selection unit 110, total reflection time measurement unit 120, section-by-section propagation speed acquisition unit 130, and impedance displacement position detection unit 140 is given with reference to FIGS. 2 to 6. can be explained with reference to

The above description of the impedance change location detection device according to the embodiment of the present invention and the description of the impedance change location method described later may be applied to each other complementary to each other.

2 is an exemplary view of a method for detecting a location of an impedance change according to an embodiment of the present invention.

Referring to FIGS. 1 and 2, a method for detecting a position of an impedance change according to an embodiment of the present invention includes a first step of selecting a plurality of reference wires (S100), wire lengths for each section (dLY1, dvia, dLY7) and The second step (S200) of obtaining the total reflection time (t1total, t2total, t3total), and the third step (S300) of obtaining the propagation time (tLY1,tvia,tLY7) and propagation speed (VLY1,Vvia,VLY7) for each section. , and a fourth step (S400) of detecting the location of the impedance change.

First, in the first step (S100), a plurality of reference wires (L1, L2, L3 in FIG. 3) can be selected from among a plurality of wires on the board, ) may include a plurality of intervals. For example, the first step ( S100 ) may be performed by the reference wire selector 100 of FIG. 1 .

Next, in the second step (S200), for each section of the plurality of reference wires (L1, L2, L3 in FIG. 3), the wire lengths (dLY1, dvia, dLY7) for each section are extracted, and the total reflection time (t1total,t2total,t3total) can be measured. For example, the second step ( S200 ) may be performed by the total reflection time measuring unit 120 of FIG. 1 .

Next, in the third step (S300), the propagation period for each section using the wire lengths (dLY1, dvia, dLY7) and the total reflection time (t1total, t2total, t3total) for each of the plurality of reference wires. (tLY1,tvia,tLY7) is obtained, and the propagation speed (VLY1,Vvia,VLY7) for each section is calculated using the propagation time (tLY1,tvia,tLY7) for each section and the wiring length (dLY1,dvia,dLY7) for each section. can be saved For example, the third step (S300) may be performed by the section-by-section propagation speed acquisition unit 130 of FIG. 1 .

Next, in the fourth step (S400), the impedance change position can be detected using the propagation speeds VLY1, Vvia, and VLY7 for each section. For example, the fourth step ( S400 ) may be performed by the impedance displacement position detection unit 140 of FIG. 1 .

For each drawing of the present invention, unnecessary redundant descriptions of the components having the same reference numerals and the same functions can be omitted, and possible differences can be described for each drawing.

3 is an exemplary view of a reference wiring of a board according to an embodiment of the present invention.

Referring to FIGS. 1 to 3 , a plurality of wires may be disposed on the substrate 20 to be inspected, and a plurality of reference wires L1, L2, and L3 may be selected from among the plurality of wires. Here, L1, L2, and L3 mean the entire wiring.

As shown in FIG. 3, each of the plurality of reference wires L1, L2, and L3 to be inspected includes, for example, a first-layer wiring LY1, a via (Via1-7), and a seventh-layer wiring (LY7) and vias (Via7-8) of the 7th and 8th layers. Here, LY1 and LY7 mean the first layer wiring and the seventh layer wiring.

For example, the first layer wiring LY1 may include three wirings 1L1, 1L2, and 1L3, and the seventh layer wiring LY7 may include three wirings 7L1, 7L2, and 7L3. The three wires 1L1, 1L2, and 1L3 of the first-layer wiring LY1 and the three wires 7L1, 7L2, and 7L3 of the seventh-layer wiring LY7 pass through the first- to seventh-layer vias Via1-7. can be connected.

For example, the lengths of the three wires 1L1, 1L2, and 1L3 included in the first layer wire LY1 are dL1-LY1, dL2-LY1, and dL3-LY1, and the first layer wire LY1 is The time for each of the three wires (1L1, 1L2, and 1L3) included is tL1-LY1, tL2-LY1, and tL3-LY3, and the three wires (1L1, 1L2, 1L3) can be referred to as vLY1.

The lengths of each of the three lines 7L1, 7L2, and 7L3 included in the seventh layer line LY7 are dL1-LY7, dL2-LY7, and dL3-LY7, and the lengths of the three lines 7L1, 7L2, and 7L3 included in the seventh layer line LY7 The times for each of the lines 7L1, 7L2, and 7L3 are tL1-LY7, tL2-LY7, and tL3-LY7, and for the three lines 7L1, 7L2, and 7L3 included in the seventh layer wiring LY7, The speed can be said to be vLY7.

In addition, first- to seventh-layer vias Via1 connecting three wires 1L1, 1L2, and 1L3 to the first-layer wire LY1 and three wires 7L1, 7L2, and 7L3 to the seventh-layer wire LY7 -7) and the 7th-layer via (Via7-8) connected to the 7th-layer wiring (LY7) by three wires (7L1, 7L2, 7L3), the distance, time, and speed are called dvia, tvia, and vvia. can do.

Referring to FIG. 3 , since the first layer wiring LY1 is on the uppermost surface of the substrate, the dielectric is in contact with the lower surface thereof. Since the seventh layer wiring LY7 is inside the substrate 20, the dielectric is in contact with both the top and bottom of the wiring.

Since the states in which the dielectrics are in contact with each other are different, the speed at which voltage signals are sent from the first layer wiring LY1 and the seventh layer wiring LY7 may be different. In addition, since the structure of the via wiring is different from that of the first layer wiring and the seventh layer wiring, the speed of the voltage signal may be different.

As described above, the wiring of the substrate 20 to be inspected may be a wiring in which three types of different voltage transmission rates are mixed. can be accurately interpreted or detected.

Referring to FIGS. 2 and 3 , in the first step (S100) of selecting the plurality of reference wires, three reference wires L1, L2, and L3 are selected as a plurality of reference wires in the substrate to be inspected. can In this document, as an example, three reference lines L1, L2, and L3 are described, but this is only for convenience of description and understanding, but is not limited thereto.

For example, each of the three reference wirings L1, L2, and L3 is a first-layer wiring LY1 and a seventh-layer wiring LY7 to be analyzed. and Via wirings (Via1-7) between the first to seventh layers and Via wirings (Via7-8) between the seventh and eighth layers may be mixed.

Also, each of the three reference wires L1 , L2 , and L3 may be wires having different distances from each other.

For example, three reference wires are selected because it is a wire in which three types of different propagation speeds are mixed. As another example, when a wire in which n types of different propagation speeds are mixed is to be investigated, n number of reference wires are selected. It can be.

4 is an exemplary view of reflection time of a reference line.

2 to 4, in the second step (S200), the process of extracting the wire lengths (dLY1, dvia, dLY7) for each section (S210) and measuring the total reflection time (t1total, t2total, t3total) It may include a process (S220) of doing.

In the process of extracting the wire lengths dLY1 , dvia , and dLY7 for each section ( S210 ), the wire lengths dLY1 , dvia , and dLY7 for each section may be extracted for the plurality of reference wires.

In the step of measuring the total reflection time (t1total, t2total, t3total) (S220), the total reflection time (t1total, t2total, t3total) for each section of the plurality of reference wires may be measured.

For example, in the second step (S200), with respect to each of the three reference wires (L1, L2, L3), three types of structural wire lengths (dL1-LY1, dvia, dL1-LY7) having different speeds ( dL2-LY1, dvia, dL2-LY7) (dL3-LY1, dvia, dL3-LY7) may be extracted from design data stored in the memory unit ( 150 in FIG. 1 ). Here, L1-LY1, dvia, and dL1-LY7 are wiring lengths for the first reference wiring L1, dL2-LY1, dvia, and dL2-LY7 are wiring lengths for the second reference wiring L2, and dL3-LY1 , dvia, and dL3-LY7 are wiring lengths for the third reference wiring L3.

As an example, the via wiring of the three reference wires (L1, L2, L3) is the substrate thickness, and since it is common, the extracted wiring length for each section is dL1-LY1, dL1-LY7 as shown in FIG. , dL2-LY1, dL2-LY7, dL3-LY1, dL3-LY7, dviacan be seven.

As an example, three reference wires (L1, L2, L3) were selected and seven distance values were extracted because the wires were mixed with three types of different propagation speeds.

Accordingly, in the case where n types of wires having different propagation velocities are mixed as an object of investigation, n reference wires may be selected and n*(n-1)+1 distance values may be extracted.

2 to 4, in the third step (S300), for each of the plurality of reference wires (L1, L2, L3), the wire lengths (dL1-LY1, dL1-LY7, dL2- LY1, dL2-LY7, dL3-LY1, dL3-LY7, dvia) and the total reflection time (t1total, t2total, t3total), the propagation time for each section (tL1-LY1, tL1-LY7, tL2-LY1, tL2 -LY7, tL3-LY1, tL3-LY7, tvia) can be obtained.

For example, as shown in FIG. 4, the TDR waveforms for the three reference wires L1, L2, and L3 are acquired, and the detection time points for each of the three reference wires L1, L2, and L3 obtained ( The reflection time (t1total, t2total, t3total) (or reflection time) from the probe point to the terminal point can be measured.

For example, in the third step (S300), for the plurality of reference wires, the wire lengths for each section (dL1-LY1, dL1-LY7, dL2-LY1, dL2-LY7, dL3-LY1, dL3-LY7 , dvia) and the measured reflection times (t1total, t2total, t3total) as matrix parameters by solving the matrix equation to determine the propagation times for each section (tL1-LY1, tL1-LY7, tL2-LY1, tL2-LY7, tL3- LY1, tL3-LY7, tvia) can be measured.

For example, in the process of obtaining the propagation speeds (VLY1, Vvia, VLY7) for each section (S320), the wire lengths for each section (dL1-LY1, dL1-LY7, dL2-LY1, dL2-LY7, dL3-LY1, dL3 -LY7, dvia) and the propagation time (tL1-LY1, tL1-LY7, tL2-LY1, tL2-LY7, tL3-LY1, tL3-LY7, tvia), the three reference wires (L1, L2, L3) propagation speeds for each section (VL1, Vvia, VL7) can be obtained.

For example, the propagation times (tL1-LY1, tL1-LY7, tL2-LY1, tL2-LY7, tL3-LY1, tL3-LY7, tvia) and the wiring lengths for each section (dL1-LY1, dL1-LY7, dL2- LY2, dL2-LY7, dL3-LY1, dL3-LY7, dvia), propagation speeds (VL1, Vvia, VL7) for each structure can be obtained.

Meanwhile, parameters related to wiring distance, propagation time, propagation speed, and reflection time related to the three reference wires L1, L2, and L3 are shown in Table 1 below.

[Table 1]

Referring to Table 1, each of L1, L2, and L3 is three reference wires. LY1 is the first layer of the substrate. LY7 is the 7th layer of the board, and Via is the via of the board connecting the 1st and 7th layers and the 7th and 8th layers.

Referring to Table 1, in the third step (S300), for the plurality of reference wires, the wire lengths (dLY1, dvia, dLY7) for each section and the total reflection time (t1total, t2total, t3total) are matrix parameters The propagation time for each section (tLY1,tvia,tLY7) can be obtained by solving the following matrix equation including

Here, dLY1 includes dL1-LY1, dL2-LY1, and dL3-LY1, which are wiring lengths of the first layer, and dLY7 includes dL1-LY7, dL2-LY7, and dL3-LY7, which are wiring lengths of the seventh layer. tLY1 may include the propagation time of the first layer, tL1-LY1 tL2-LY1 tL3-LY1, and tLY7 may include the propagation time of the seventh layer, tL1-LY7 tL2-LY7 tL3-LY7.

[matrix equation]

Referring to Table 1 and the matrix equation, each of L1, L2, and L3 is three reference wires. LY1 is the first layer of the substrate. LY7 is the 7th layer of the board, and Via is the via of the 1st-8th layer board.

dL1-LY1, dL2-LY1, dL3-LY1 are the three wiring lengths of the 1st layer, dL1-LY7, dL2-LY7, dL3-LY7 are the 3 wiring lengths of the 7th layer, and dvia is the via between the 1st and 7th layers and the wiring length between the 7th and 8th floors.

tL1-LY1, tL2-LY1, and tL2-LY1 are the propagation times of the three wires on the first layer, tL1-LY7, tL2-LY7, and tL3-LY7 are the propagation times of the three wires on the seventh layer, and tvia is the propagation time of the three wires on the first layer. and is the propagation time between the vias between the 7th layer and the 7th and 8th layers.

In addition, t1total, t2total, and t3total are total reflection times for each of the three reference wires (L1, L2, and L3), and VL1, Vvia, and VL7 are propagation speeds for each of the first, via, and seventh layers.

For example, in the matrix equation of 7th row and 7th column, the upper 3rd row is an equation for the time of each reference line, and the lower 4th row is an equation for the reciprocal of the velocity.

The time for each section obtained using the matrix equation may be reflected in the TDR waveform of the reference line Line1 shown in FIG. 5 .

Next, in the fourth step (S400), a TDR waveform for each of the plurality of reference wires may be measured. This will be described later.

5 is an exemplary TDR waveform showing propagation time for each section.

Referring to the TDR waveform shown in FIG. 5 , if the obtained propagation time factor for each section is reflected in the TDR waveform of the reference line, more accurate position information can be obtained.

Referring to the above example, since the wiring has three different propagation velocities, 3 reference wires are selected and 7 time parameters are obtained by solving the matrix equation of 7 rows and 7 columns.

Using this method, if n types of wires mixed with different propagation speeds are to be investigated, n reference wires are selected and <n*(n-1)+1> rows <n*(n-1 )+1> by solving the matrix equation of the column, n*(n-1)+1 time parameters can be obtained. Here, among the matrix equations of <n*(n-1)+1> rows and <n*(n-1)+1> columns, row n is an equation for the time of n reference wires, and (n-1) ² The row can be an equation for the reciprocal of velocity.

6 is an exemplary view showing a TDR waveform of a normal wiring and a TDR waveform of a defective wiring showing propagation time for each section.

In FIG. 6, Gref is a TDR waveform diagram for a normal wiring, and Gopen is a TDR waveform diagram for a defective wiring.

Referring to FIG. 6 , in the fourth step ( S400 ), a process ( S420 ) of detecting a position of an impedance change may be performed using the obtained propagation times (tLY1,tvia,tLY7) for each section (S410).

In the process of detecting the impedance change position (S420), the impedance change position may be detected based on the propagation time for each section (tLY1,tvia,tLY7).

For example, after obtaining the propagation speed for each structure in the above process, an example of an impedance abnormal reflection position will be described.

For example, it is possible to determine where the line is disconnected with respect to the wiring determined to be a disconnection defect in an electrical inspection or the like through analysis.

As an example, the wiring structure of the board to be analyzed may be a wiring passing through the first layer wiring → Via1-7 → seventh layer wiring → Via7-8, as described above.

As described above, the TDR waveform of the normal wiring of the reference wiring of the substrate to be inspected is the same as Gref in FIG.

Next, the propagation time for each section can be obtained from the propagation speed for each structure obtained in the above process and the wiring length (dLY1, dvia, dLY7) for each section of the reference wiring extracted from the design data of the wiring to be analyzed. is as shown in Figure 6.

Referring to the TDR waveforms Gref and Gopen shown in FIG. 6 , based on the data of the TDR waveform shown in FIG.

In addition, when analyzing using the propagation speed of the seventh layer and the TDR time reflected from the disconnection, it can be specified that there is a disconnection at the position of 7.83 mm in the seventh layer.

Through the test result as described above, it can be seen that the location can be specified with higher accuracy than the location specified from the average propagation speed of the entire reference line.

On the other hand, the impedance change location detection device 100 according to an embodiment of the present invention is a processor (eg, a central processing unit (CPU), a graphics processing unit (GPU), a microprocessor, an application specific integrated circuit (ASIC)) ), Field Programmable Gate Arrays (FPGA), etc.), memory (e.g., volatile memory (e.g., RAM, etc.), non-volatile memory (e.g., ROM, flash memory, etc.), input device (e.g., keyboard, mouse, etc.) , pen, voice input device, touch input device, infrared camera, video input device, etc.), output device (eg display, speaker, printer, etc.) and communication access device (eg modem, network interface card (NIC), integrated network A computing environment in which interfaces, radio frequency transmitters/receivers, infrared ports, USB interfaces, etc.) are interconnected with each other (e.g. Peripheral Component Interconnect (PCI), USB, firmware (IEEE 1394), optical bus structures, networks, etc.) can be implemented as

The computing environment may be a personal computer, server computer, handheld or laptop device, mobile device (mobile phone, PDA, media player, etc.), multiprocessor system, consumer electronic device, mini computer, mainframe computer, any of the foregoing systems or It may be implemented in a distributed computing environment including devices, but is not limited thereto.

In the above, the present invention has been described as an embodiment, but the present invention is not limited to the above-described embodiments, and those skilled in the art in the field to which the invention pertains without departing from the gist of the present invention claimed in the claims Anyone can make a variety of variations.

100: impedance change position detection device
110: reference wiring selection unit
120: total reflection time measuring unit
130: propagation speed acquisition unit for each section
140: impedance displacement position detection unit
150: memory unit

Claims (16)

a reference wire selection unit that selects a plurality of reference wires from among a plurality of wires of the substrate, and the plurality of reference wires includes a plurality of sections;
a total reflection time measurement unit extracting wire lengths for each section of the plurality of reference wires and measuring a total reflection time for each of the plurality of reference wires;
a section-by-section propagation speed obtainer for obtaining a propagation speed at each section using the wire length for each section and the total reflection time; and
an impedance displacement position detection unit for detecting a position of impedance change using the propagation speed for each section;
Impedance change location detection device comprising a.
The method of claim 1, wherein the plurality of reference wires
Including the plurality of sections in which different propagation speeds are mixed
Impedance change position detection device.
The method of claim 1, wherein the total reflection time measuring unit,
Extracting the wire length for each section for each of the plurality of reference wires based on distance data stored in a memory unit
Impedance change position detection device comprising a.
The method of claim 3, wherein the total reflection time measuring unit,
Obtaining a TDR waveform for each of the plurality of reference wires, and obtaining the total reflection time based on the TDR waveform
Impedance change position detection device.
The method of claim 1, wherein the propagation speed acquisition unit for each section,
Obtaining a reflection time for each section of the plurality of reference wires using the wire length for each section and the total reflection time;
Obtaining the propagation speed for each section for each of the plurality of reference wires using the wire length for each section and the reflection time for each section
Impedance change position detection device.
The method of claim 5, wherein the propagation speed acquisition unit for each section,
For the plurality of reference wires, solving a matrix equation including the wire length for each section and the total reflection time as matrix parameters to obtain the reflection time for each section
Impedance change position detection device.
The method of claim 6, wherein the impedance displacement position detection unit,
Detecting the impedance change position based on the propagation speed for each section and the reflection time for each section
Impedance change position detection device.
The method of claim 5, wherein the propagation speed acquisition unit for each section,
For the plurality of reference wirings, the reflection time for each section is obtained by solving the following matrix equation including the wiring length for each section and the total reflection time as matrix parameters;
<Matrix equation>

Here, each of L1, L2, and L3 is three reference wires, and LY1 is the first layer of the board. LY7 is the 7th layer of the board, Via is the via of the board, dL1-LY1, dL2-LY1, dL3-LY1 are the three wiring lengths of the 1st layer, and dL1-LY7, dL2-LY7, dL3-LY7 are the 7th layer 3 wire length, dvia is the wire length of the via, tL1-LY1, tL2-LY1, tL2-LY1 are the propagation times of the 3 wires on the 1st layer, tL1-LY7, tL2-LY7, tL3-LY7 are the 7th layer is the propagation time of the three wires, tvia is the propagation time of the via, t1total, t2total, and t3total are the reflection times for each of the three reference wires L1, L2, and L3, and VL1, Vvia, and VL7 are the first layer, via , which is the propagation speed for each of the 7 layers
Impedance change position detection device.
A first step of selecting a plurality of reference wires from among a plurality of wires of a substrate, wherein the plurality of reference wires include a plurality of sections;
a second step of extracting wire lengths for each section of the plurality of reference wires and measuring a total reflection time for each of the plurality of reference wires;
a third step of obtaining a propagation speed for each section using the wire length for each section and the total reflection time; and
a fourth step of detecting a position of impedance change using the propagation speed for each section;
Impedance change position detection method comprising a.
10. The method of claim 9, wherein the plurality of reference wires
Including the plurality of sections in which different propagation speeds are mixed
Impedance change location detection method.
The method of claim 9, wherein the second step,
Extracting the wire length for each section for each of the plurality of reference wires based on distance data stored in the memory unit 150
Impedance change location detection method.
The method of claim 11, wherein the second step,
Obtaining a TDR waveform for each of the plurality of reference wires, and obtaining the total reflection time based on the TDR waveform
Impedance change location detection method.
The method of claim 9, wherein the third step,
obtaining a propagation time for each section of the plurality of reference wires using the wire length for each section and the total reflection time; and
obtaining the propagation speed for each section of the plurality of reference wires using the wire length for each section and the propagation time for each section;
Impedance change location detection method comprising a
The method of claim 13, wherein the third step,
For the plurality of reference wires, solving a matrix equation including the wire length for each section and the total reflection time as matrix parameters to obtain the propagation time for each section
Impedance change location detection method.
The method of claim 9, wherein the fourth step,
Impedance change position detection method for detecting the impedance change position based on the propagation speed for each section and the propagation time for each section.
The method of claim 13, wherein the third step,
For the plurality of reference wires, the propagation time for each section is obtained by solving the following matrix equation including the wire length for each section and the total reflection time as matrix parameters;
<Matrix equation>

Here, each of L1, L2, and L3 is three reference wires, and LY1 is the first layer of the board. LY7 is the 7th layer of the board, Via is the via of the board, dL1-LY1, dL2-LY1, dL3-LY1 are the three wiring lengths of the 1st layer, and dL1-LY7, dL2-LY7, dL3-LY7 are the 7th layer 3 wire length, dvia is the wire length of the via, tL1-LY1, tL2-LY1, tL2-LY1 are the propagation times of the 3 wires on the 1st layer, tL1-LY7, tL2-LY7, tL3-LY7 are the 7th layer is the propagation time of the three wires, tvia is the propagation time of the via, t1total, t2total, and t3total are the reflection times for each of the three reference wires L1, L2, and L3, and VL1, Vvia, and VL7 are the first layer, via , which is the propagation speed for each of the 7 layers
Impedance change location detection method.

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