PCB Iindlela zokwenza iintambo ziyaqhubeka nokuphucuka, kwaye ubuchwephesha bokubamba iingcingo bunokunciphisa ubude bocingo kunye nokukhulula indawo engaphezulu yePCB. Ukubiyelwa kwe-PCB yesiqhelo kunqunyelwe kulungelelwaniso lweengcingo ezingaguqukiyo kunye nokusilela kweengcingo ezi-angled ngokungekho semthethweni. Ukususa ezi zithintelo kunokuphucula kakhulu umgangatho weentambo.

Let’s start with some terminology. Sichaza i-Angle wiring ye-wiring njenge-wiring yocingo usebenzisa amacandelo e-Angle kunye nama-radians. Luhlobo lwentambo yocingo, kodwa aluphelelanga ekusebenziseni kuphela iidigri ezingama-90 kunye nama-45 eedigri zemigca yeAngle. 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. Masilichaze igama elithi iintambo eziguqukayo njengeentambo zentambo ngaphandle kwemilo emiselweyo eyenza ukuba ukubalwa kwakhona kwentsimbi yexesha lokwenyani kufezekise oku kulandelayo. Kuphela zii-arcs ezivela kwimiqobo kunye neetangents zazo eziqhelekileyo ezisetyenziselwa ukwenza ubume bomgca. (Obstacles include pins, copper foil, forbidden areas, holes and other objects) part of the circuit of two PCB models. Iingcingo eziluhlaza nezibomvu zihamba ngeendlela ezahlukeneyo zemodeli yePCB. 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. Umzobo 1B yimodeli ye-PCB isebenzisa ii-arcs kunye nee-angles ezingabonakaliyo. 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. Ibonisa i-PCB yokwenyani ephuhliswe ngo-1972 yinkampani yaseMelika ebizwa ngokuba yiDigibarn yokufaka iintambo ngokugqibeleleyo. This is a PCB board based on Intel8008 computer. I-wiring ye-Angle engenakuphikiswa eboniswe kuMzobo 2 iyafana. Kutheni le nto beya kusebenzisa i-Angle wiring? Ngenxa yokuba olu hlobo lweentambo lunezinto ezininzi eziluncedo. Arbitrary Angle wiring has many advantages. Okokuqala, ukungasebenzisi ii-angles phakathi kwamacandelo emigca kugcina indawo yePCB (iipoligoni zihlala zithatha indawo engaphezulu kuneetangents). Traditional automatic cablers can place only three wires between adjacent components (see left and center in Figure 3). Nangona kunjalo, xa kufakwe iingcingo kuyo nayiphi na i-Angle, kukho indawo eyaneleyo yokubeka iingcingo ezi-4 kwindlela enye ngaphandle kokophula umthetho wokujonga uyilo (i-DRC). Masithi sinendlela ye-chip elungileyo kwaye sifuna ukudibanisa izikhonkwane ze-chip kwezinye izikhonkwane ezibini. Using only 90 degrees takes up a lot of space. Ukusebenzisa i-Angle wiring ngokungafaniyo kunokunciphisa umgama phakathi kwe-chip kunye nezinye izikhonkwane, ngelixa unciphisa ukunyathela. In this case, the area was reduced from 30 square centimeters to 23 square centimeters. Ukujikeleza i-chip nakweyiphi i-Angle nako kunokubonelela ngeziphumo ezingcono. 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. Le ayisiyiyo ithiyori kuphela, kodwa ikwasisisombululo esisebenzayo (ngamanye amaxesha sisisombululo ekuphela kwaso esinokubakho). Shows an example of a simple PCB. Iziphumo zetheyibhile yetopiya, ngelixa iziphumo ezizenzekelayo zecandelo esekwe kwimilo efanelekileyo ziifoto zePCB eyiyo. An automatic cabler based on optimal shape cannot do this because the components are rotated at arbitrary angles. Udinga indawo engaphezulu, kwaye ukuba awujikelezisi izinto, isixhobo kufuneka senziwe sikhulu. 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. Ukuba kukho i-Angle phakathi kwamacandelo ocingo, ke njengoko le Angle inyuka, inqanaba le-crosstalk liyakwehla. 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. Qwalasela ezi ndlela zintathu zilandelayo zokubamba iintambo. 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. I-cablerr ngokuzenzekelayo ibala ubume obulungileyo becingo (kuthathelwa ingqalelo ukhuseleko oluyimfuneko). Ukwenza i-cabling eguqukayo kungalinciphisa kakhulu ixesha elifunekayo lokuhlela i-topology, ixhasa ngokufanelekileyo ukuphindaphinda okuninzi ukuze kuhlangane iingxaki. Oku kubonisa uyilo lwePCB oluhamba ngemingxunya kunye namanqaku esebe. Ngexesha lokuhamba okuzenzekelayo, iingongoma zesebe locingo kunye nemingxunya evulekileyo ihlengahlengiswa kwindawo efanelekileyo. 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. Xa indlela ifunyenwe, ilungisiwe kwaye iba yinxalenye yemaze. Ukungancedi kweentambo ezilandelelanayo kukuba isiphumo se-wiring sinokuxhomekeka kulungelelwaniso lweentambo. Xa umgangatho wethopholoji usekude ngokugqibeleleyo, ingxaki “yokubambeka” yenzeka kwiindawo ezincinci zalapha. 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. Ukugoba ngocingo kubhekisa kwinto yokuba ucingo kwinethiwekhi enye kufuneka lujikeleze into kwenye inethiwekhi ukufikelela kwinto. Rewiring a wire will not correct this. Umzekelo wokugoba ubonakalisiwe. A lit red wire travels around a pin in the other network, and an unlit red wire connects to this pin. Iziphumo zokulungisa ezizenzekelayo zibonisiwe. 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. Iingcingo ezibomvu ezibomvu ziyaqaqanjiswa. Kumthi we-Steiner, yonke imigca kufuneka idityaniswe njengamacandelo kwiivente (iindawo zokuphela kunye nezongezo). Ngaphezulu kwe-vertex entsha nganye, amacandelo amathathu kufuneka ahlangane kwaye kungabikho ngaphezulu kwamacandelo amathathu ekufuneka aphele. The Angle between the line segments that converge to the vertex shall not be less than 120 degrees. Akunzima kakhulu ukwakha iSteiner ngezi zinto zaneleyo zemiqathango, kodwa oko akuthethi ukuba kuncinci. Gray Steiner trees are not optimal, but black Steiner trees are. Kuyilo lonxibelelwano olusebenzayo, iintlobo ezahlukeneyo zemiqobo kufuneka ziqwalaselwe. Banciphisa amandla okwakha ubuncinci bemithi besebenzisa ii-algorithms kunye nemithi yeSteiner besebenzisa iindlela zejiyometri. 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. Eyona nto iphambili apha yindlela yokusebenza esekwe kumandla ebala imikhosi esebenza kwi-vertices ezintsha kwaye izihambisa ngokuphindaphindiweyo kwindawo yokulingana (ubukhulu kunye nolwalathiso lwemikhosi luxhomekeke kwiingcingo kwiindawo zamasebe ezikufutshane). Ukuba i-Angle phakathi kwamacandelo emigca exhunywe kwi-vertex (i-terminus okanye ukongeza) ingaphantsi kwe-120 degrees, inqaku lesebe linokongezwa, emva koko i-algorithm yoomatshini inokusetyenziselwa ukwandisa indawo ye-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. Ikwavumela iindawo apho uxhulumaniso lweendawo zokuphela ezingavumelekanga, kwaye inani leendawo zokugqibela zingangqinelana.

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. Olunye lomaleko kulo mzobo luye lwasinda kwiingcingo. Umzobo 16 ubonisa ikota ye-BGA. Kwangelo xesha, xa usebenzisa indlela “yokubamba umda”, inani lamajelo afunekayo ukuphuma kumda wokutshintsha awutshintshi kumaleko ukuya kuluhlu. Oku kuya kulinciphisa kakhulu inani leendlela. Kwicandelo lobungakanani be-28x28mm, 7 maleko anele. Kumacandelo amakhulu, kukuphumelela. 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. Ngokuzenzekelayo i-Angle topological ikhebula oluzenzekelayo linokukwenza oku. 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.