PCB cara kabel terus apik, lan teknik kabel fleksibel bisa nyuda dawa kabel lan mbebasake papan PCB luwih akeh. Kabel PCB konvensional diwatesi dening koordinat kawat tetep lan ora ana kabel kanthi sudut sithik. Mbusak watesan kasebut bisa nambah kualitas kabel kanthi signifikan.

Let’s start with some terminology. Kita nemtokake kabel Angle sing kasepakatan minangka kabel kawat nggunakake segmen Angle sing wenang lan radian. Iki minangka jinis kabel kawat, nanging ora diwatesi mung nggunakake 90 derajat lan 45 derajat garis Angle. Topological wiring is wire wiring that does not adhere to grids and coordinates and does not use regular or irregular grids like shape-based wiring. Ayo jelasake istilah kabel fleksibel minangka kabel kabel tanpa bentuk tetep sing mbisakake kalkulasi bentuk kawat wektu nyata kanggo nggayuh kemungkinan transformasi ing ngisor iki. Mung busur saka alangan lan tangen umum sing digunakake kanggo mbentuk bentuk garis. (Obstacles include pins, copper foil, forbidden areas, holes and other objects) part of the circuit of two PCB models. Kawat ijo lan abang mbukak ing macem-macem lapisan model PCB. The blue circles are the perforations. The red element is highlighted. There are also some red round pins. Use only line segments and models with an Angle of 90 degrees between them. Gambar 1B minangka model PCB nggunakake busur lan sudut sawenang-wenang. Wiring at any Angle may seem strange, but it does have many advantages. The way it is wired is very similar to how engineers wired it by hand half a century ago. Nuduhake PCB nyata sing dikembangake ing taun 1972 dening perusahaan Amerika sing diarani Digibarn kanggo kabel tangan lengkap. This is a PCB board based on Intel8008 computer. Kabel Angle sing kasepakatan sing ditampilake ing Gambar 2 sejatine padha. Napa dheweke nggunakake kabel Angle sing sewenang-wenang? Amarga jinis kabel iki akeh mupangate. Arbitrary Angle wiring has many advantages. Kaping pisanan, ora nggunakake sudhut ing antarane segmen garis ngirit ruangan PCB (poligon mesthi njupuk papan luwih akeh tinimbang tangen). Traditional automatic cablers can place only three wires between adjacent components (see left and center in Figure 3). Nanging, nalika kabel ing Angle, ana cukup ruang kanggo nyelehake 4 kabel ing jalur sing padha tanpa nglanggar pamriksa aturan desain (DRC). Umpama kita duwe chip mode positif lan pengin nyambungake pin chip menyang rong pin liyane. Using only 90 degrees takes up a lot of space. Nggunakake kabel Angle sing sewenang-wenang bisa nyuda jarak antarane chip lan pin liyane, nalika nyuda jejak. In this case, the area was reduced from 30 square centimeters to 23 square centimeters. Muter chip ing Angle apa wae uga bisa menehi asil sing luwih apik. In this case, the area was reduced from 23 square centimeters to 10 square centimeters. It shows a real PCB. Arbitrary Angle wiring with rotating chip function is the only wiring method for this circuit board. Iki ora mung teori, nanging uga solusi praktis (kadang solusi mung bisa uga). Shows an example of a simple PCB. Asil cabler topologi, dene asil cabler otomatis adhedhasar bentuk optimal yaiku foto PCB nyata. An automatic cabler based on optimal shape cannot do this because the components are rotated at arbitrary angles. Sampeyan mbutuhake area sing luwih akeh, lan yen ora muter komponen kasebut, piranti kudu digawe luwih gedhe. Kinerja tata letak bakal saya apik tanpa perangan paralel, sing asring dadi sumber crosstalk. The level of crosstalk increases linearly as the length of parallel wires increases. As the spacing between parallel wires increases, crosstalk decreases quadratic. Let’s set the level of crosstalk produced by two parallel 1mm wires spaced d to e. Yen ana Angle ing antarane segmen kawat, mula nalika Angle iki mundhak, level crosstalk bakal mudhun. The crosstalk does not depend on the length of the wire, but only on the Angle value: where α represents the Angle between the wire segments. Coba pikirake telung metode kabel ing ngisor iki. On the left side of Figure 8 (90 degree layout), there is the maximum wire length and the maximum emi value due to parallel line segments. In the middle of Figure 8 (45 degree layout), the wire length and emi values are reduced. On the right-hand side (at any Angle), the wire length is shortest and there are no parallel wire segments, so the interference value is negligible. So arbitrary Angle wiring helps to reduce the total wire length and significantly reduce electromagnetic interference. You also remember the effect on signal delay (conductors should not be parallel and should not be perpendicular to the PCB fiberglass). Advantages of flexible wiring Manual and automatic movement of components does not destroy the wiring in flexible wiring. Kabel kanthi otomatis ngitung bentuk kawat sing optimal (kanthi nggunakake kunci keamanan sing dibutuhake). Kabel sing fleksibel bisa nyuda wektu sing dibutuhake kanggo nyunting topologi, kanthi ndhukung macem-macem rekrut kanggo nemokake kendala. Iki nuduhake desain PCB sing ngliwati bolongan lan titik cabang. Sajrone gerakan otomatis, titik cabang kawat lan bolongan disetel menyang posisi sing optimal. In most computer-aided design (CAD) systems, the wiring interconnection problem is reduced to the problem of sequentially finding paths between pairs of points in a maze of pads, forbidden areas, and laid wires. Yen ditemokake, dalan kasebut tetep lan dadi bagian saka labirin. Kerugian kabel urutan yaiku asil kabel bisa uga gumantung karo urutan kabel. Nalika kualitas topologis isih durung sampurna, masalah “macet” kedadeyan ing wilayah cilik. But no matter which wire you rewire, it’s not going to improve the quality of the wiring. This is a serious problem in all CAD systems using sequential optimization. This is where the bending elimination process is useful. Bending kabel nuduhake kedadeyane yen kabel ing siji jaringan kudu ngubengi obyek ing jaringan liya kanggo ngakses obyek. Rewiring a wire will not correct this. Tuladhane mlengkung ditampilake. A lit red wire travels around a pin in the other network, and an unlit red wire connects to this pin. Hasil pamrosesan otomatis ditampilake. In the second case (on another layer), a lighted green wire is automatically rewired by changing the wiring layer (from green to red). Eliminate wire bending by automatically optimizing wire shape (approximate arcs with line segments just to show any Angle examples without arcs). (top) original design, (bottom) after eliminating bending design. Kabel bengkok abang disorot. Ing wit Steiner, kabeh baris kudu disambungake minangka segmen menyang simpul (titik mburi lan tambahan). Ing sisih ndhuwur saben vertex anyar, telung segmen kudu gabung lan ora luwih saka telung segmen bakal mungkasi. The Angle between the line segments that converge to the vertex shall not be less than 120 degrees. Ora angel banget nggawe Steiner kanthi sifat kondisional sing cukup, nanging durung mesthi minimal. Gray Steiner trees are not optimal, but black Steiner trees are. Ing desain komunikasi praktis, macem-macem jinis alangan kudu dipikirake. Dheweke matesi kemampuan kanggo mbangun wit jembar minimal nggunakake kaloro algoritma lan wit Steiner nggunakake metode geometris. The obstacles are shown in gray and we recommend starting at any end vertex. If there is more than one adjacent terminating vertex, you should choose one that allows you to continue using the second vertex. It depends on the Angle. Mekanisme utama ing kene yaiku algoritma adhedhasar kekuwatan sing ngitung kekuwatan sing tumindak ing simpul anyar lan bola-bali pindhah menyang titik keseimbangan (gedhene lan arah gaya gumantung karo kabel ing titik cabang sing jejer). Yen Angle ing antarane sepasang segmen garis sing nyambung menyang vertex (terminus utawa Kajaba) kurang saka 120 derajat, bisa ditambah titik cabang, lan banjur algoritma mekanik bisa digunakake kanggo ngoptimalake posisi vertex. It’s worth noting that simply sorting all angles in descending order and adding new vertices in that order doesn’t work, and the result is worse. After adding a new node, you should check the minimum of a subnet consisting of four pins:

1. If a vertex is added to the vicinity of another newly added vertex, check for the smallest four-pin network.

2. If the four-pin network is not minimal, select a pair of “diagonal” (belonging to the quadrilateral diagonal) endpoints or virtual terminal nodes (virtual terminal nodes – wire bends).

3. The line segment that connects the endpoint (virtual endpoint) to the nearest new vertex is replaced by the line segment that connects the endpoint (virtual endpoint) to the distant new vertex.

4. Use mechanical algorithms to optimize vertex positions.

This method does not guarantee to build the smallest network, but compared with other methods, it can achieve the smallest network length without grazing. Uga ngidini area sing dilarang koneksi endpoint, lan nomer simpul endpoint bisa uga kasewenang-wenang.

Flexible wiring at any Angle has some other interesting advantages. For example, if you can automatically move many objects with the help of automatic real-time wire shape recalculation, you can create parallel serpentine lines. This cabling method makes better use of space, minimizes the number of iterations, and allows for flexible use of tolerances. If there are two serpentine lines interlaced with each other, the automatic cabler will reduce the length of one or both, depending on rule priority.

Consider the wiring of BGA components. In the traditional peripheral-to-center approach, the number of channels to the periphery is reduced by 8 with each successive layer (due to a reduction in perimeter). For example, a 28x28mm component with 784 pins requires 10 layers. Sawetara lapisan ing diagram wis uwal saka kabel. Gambar 16 nuduhake seprapat BGA. Sanalika, nalika nggunakake metode kabel “tengah kanggo pinggiran”, jumlah saluran sing dibutuhake kanggo metu menyang pinggiran ora bakal ganti saka lapisan menyang lapisan. Iki bakal nyuda akeh lapisan. Kanggo ukuran komponen 28x28mm, cukup 7 lapisan. Kanggo komponen sing luwih gedhe, win-win. Figure 17 shows a quarter of the BGA. An example of BGA wiring is shown. When using the “center to periphery” cabling approach, we can complete the cabling of all networks. Kabler otomatis topologis Arbitrary Angle bisa nindakake iki. Traditional automatic cablers cannot route this example. Shows an example of a real PCB where the engineer reduced the number of signal layers from 6 to 4 (compared to the specification). In addition, it took engineers only half a day to complete the wiring of the PCB.