PCB simlarni ulash usullari takomillashishda davom etmoqda va moslashuvchan simlarni ulash usullari sim uzunligini qisqartirishi va ko’proq tenglikni bo’sh joyini bo’shatishi mumkin. An’anaviy tenglikni simlari qattiq simli koordinatalar va o’zboshimchalik bilan burchakli simlarning yo’qligi bilan cheklangan. Ushbu cheklovlarni olib tashlash simlarning sifatini sezilarli darajada yaxshilashi mumkin.

Let’s start with some terminology. Biz ixtiyoriy burchakli simlarni ixtiyoriy burchak segmentlari va radianlardan foydalangan holda simli simlar sifatida aniqlaymiz. Bu simli simlarning bir turi, lekin faqat 90 daraja va 45 graduslik burchakli chiziqli segmentlarni ishlatish bilan cheklanmaydi. 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. Keling, moslashuvchan simlar atamasini aniq shaklsiz simli simlar sifatida aniqlaymiz, bu real vaqt rejimida simlarning shaklini qayta hisoblash imkonini beradi, bu esa quyidagi o’zgartirish imkoniyatlariga erishadi. Chiziq shaklini yaratish uchun faqat to’siqlardan yasalgan yoylar va ularning umumiy teginishlari ishlatiladi. (Obstacles include pins, copper foil, forbidden areas, holes and other objects) part of the circuit of two PCB models. Yashil va qizil simlar PCB modelining turli qatlamlarida ishlaydi. 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. Shakl 1B – yoylar va ixtiyoriy burchaklardan foydalanadigan tenglikni modeli. 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. 1972 yilda Amerikaning Digibarn kompaniyasi tomonidan to’liq qo’l simlari uchun ishlab chiqilgan haqiqiy tenglikni ko’rsatadi. This is a PCB board based on Intel8008 computer. 2 -rasmda ko’rsatilgan ixtiyoriy burchak simlari aslida o’xshash. Nega ular o’zboshimchalik bilan burchakli simlardan foydalanadilar? Chunki bu turdagi simlar ko’p afzalliklarga ega. Arbitrary Angle wiring has many advantages. Birinchidan, chiziq segmentlari orasidagi burchaklarni ishlatmaslik PCB maydonini tejaydi (ko’pburchaklar har doim teginuvchilardan ko’ra ko’proq joy egallaydi). Traditional automatic cablers can place only three wires between adjacent components (see left and center in Figure 3). Biroq, har qanday burchakda simlarni ulashda, dizayn qoidalarini tekshirishni (DRC) buzmasdan, bitta yo’lda 4 ta simni yotqizish uchun etarli joy mavjud. Faraz qilaylik, bizda ijobiy rejim chipi bor va chip pinlarini boshqa ikkita pin bilan bog’lamoqchimiz. Using only 90 degrees takes up a lot of space. Ixtiyoriy burchakli simlardan foydalanish chip va boshqa pinlar orasidagi masofani qisqartirishi mumkin, shu bilan birga oyoq izini kamaytiradi. In this case, the area was reduced from 30 square centimeters to 23 square centimeters. Rotating the chip at any Angle can also provide better results. 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. Bu nafaqat nazariya, balki amaliy echim (ba’zida yagona mumkin bo’lgan echim). Shows an example of a simple PCB. Topologiya kabeli natijalari, optimal shaklga asoslangan avtomatik kabel natijalari haqiqiy PCB fotosuratlari. An automatic cabler based on optimal shape cannot do this because the components are rotated at arbitrary angles. Sizga ko’proq maydon kerak va agar siz komponentlarni aylantirmasangiz, qurilmani kattalashtirish kerak. Layout performance would be greatly improved without parallel segments, which are often a source of 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. Agar sim bo’laklari o’rtasida burchak bo’lsa, bu burchak oshgan sari o’zaro faoliyat darajasi pasayadi. 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. Quyidagi uchta simni ulash usulini ko’rib chiqing. 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 avtomatik ravishda simning optimal shaklini hisoblab chiqadi (zarur xavfsizlik oralig’ini hisobga olgan holda). Moslashuvchan kabellar, shuning uchun ham topologiyani tahrir qilish uchun zarur bo’lgan vaqtni sezilarli darajada qisqartirishi mumkin, bu esa cheklovlarni qondirish uchun bir nechta rekablingni yaxshi qo’llab -quvvatlaydi. Bu teshiklar va novdalar orqali harakatlanadigan PCB dizaynini ko’rsatadi. Avtomatik harakatlanish vaqtida simlarning tarmoqli nuqtalari va teshiklari optimal holatga o’rnatiladi. 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. Agar yo’l topilsa, u aniqlanadi va labirintning bir qismiga aylanadi. Ketma -ket simlarni ulashning kamchiliklari shundaki, ulanish natijasi simi tartibiga bog’liq bo’lishi mumkin. Qachonki topologik sifat hali mukammallikdan uzoq bo’lsa, “qotib qolish” muammosi mahalliy kichik joylarda paydo bo’ladi. 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. Simlarning bükülmesi, bir tarmoqdagi sim, ob’ektga kirish uchun boshqa tarmoqdagi ob’ekt atrofida aylanishi kerak bo’lgan hodisani anglatadi. Rewiring a wire will not correct this. Bükme namunasi ko’rsatilgan. A lit red wire travels around a pin in the other network, and an unlit red wire connects to this pin. Avtomatik ishlash natijalari ko’rsatiladi. 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. Qizil egilgan simlar ajratilgan. Shtayner daraxtida barcha chiziqlar tepaliklarga segment sifatida ulanishi kerak (oxirgi nuqtalar va qo’shimchalar). Har bir yangi tepalikning tepasida uchta segment bir -biriga yaqinlashishi va uchdan oshmasligi kerak. The Angle between the line segments that converge to the vertex shall not be less than 120 degrees. Bu etarli shartli xususiyatlarga ega bo’lgan Shtaynerni qurish juda qiyin emas, lekin bu minimal bo’lishi shart emas. Gray Steiner trees are not optimal, but black Steiner trees are. Amaliy aloqa dizaynida har xil to’siqlarni hisobga olish kerak. Ular geometrik usullar yordamida algoritmlar yordamida ham, Shtayner daraxtlari yordamida ham minimal daraxtlarni qurish imkoniyatini cheklaydi. 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. Bu erda asosiy mexanizm-kuchga asoslangan algoritm bo’lib, u yangi cho’qqilarga ta’sir qiluvchi kuchlarni hisoblab chiqadi va ularni qayta-qayta muvozanat nuqtasiga o’tkazadi (kuchlarning kattaligi va yo’nalishi qo’shni tarmoq nuqtalaridagi simlarga bog’liq). Agar tepalikka (nuqta yoki qo’shimchaga) ulangan chiziqli segmentlar orasidagi burchak 120 darajadan past bo’lsa, tarmoq nuqtasini qo’shish mumkin, so’ngra tepalik holatini optimallashtirish uchun mexanik algoritmdan foydalanish mumkin. 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. Bu shuningdek, so’nggi nuqta ulanishlari taqiqlangan joylarga ruxsat beradi va tugunlar soni o’zboshimchalik bilan bo’lishi mumkin.

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. Diagrammadagi ba’zi qatlamlar simdan chiqib ketgan. 16 -rasmda BGA ning chorak qismi ko’rsatilgan. Shu bilan birga, “markazdan periferiyaga” simlarni ulash usuli qo’llanilganda, periferiyaga chiqish uchun zarur bo’lgan kanallar soni qatlamdan qatlamga o’zgarmaydi. Bu qatlamlar sonini sezilarli darajada kamaytiradi. 28×28 mm o’lchamdagi komponentlar uchun 7 ta qatlam etarli. Kattaroq komponentlar uchun bu g’alaba qozonadi. 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. O’zboshimchalik bilan burchakli topologik avtomatik kabellar buni qila oladi. 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.