PCB njia za wiring zinaendelea kuboreshwa, na mbinu rahisi za wiring zinaweza kupunguza urefu wa waya na kutoa nafasi zaidi ya PCB. Wiring ya kawaida ya PCB imepunguzwa na kuratibu za waya zisizohamishika na ukosefu wa waya zilizopigwa kiholela. Kuondoa mapungufu haya kunaweza kuboresha ubora wa wiring.

Let’s start with some terminology. Tunafafanua waya wa kiholela kama wiring ya waya kwa kutumia sehemu za Angle na radians. Ni aina ya wiring ya waya, lakini sio mdogo kwa kutumia digrii 90 tu na sehemu za laini ya Angle ya digrii 45. 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. Wacha tufafanue neno wiring rahisi kama wiring ya waya bila sura iliyowekwa ambayo inawezesha hesabu ya sura ya waya wa wakati halisi kufanikisha uwezekano wa mabadiliko yafuatayo. Arcs tu kutoka kwa vizuizi na tangents zao za kawaida hutumiwa kuunda sura ya mstari. (Obstacles include pins, copper foil, forbidden areas, holes and other objects) part of the circuit of two PCB models. Waya wa kijani na nyekundu hutembea kwa tabaka tofauti za mfano wa 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. Kielelezo 1B ni mfano wa PCB kwa kutumia arcs na pembe za kiholela. 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. Inaonyesha PCB halisi iliyotengenezwa mnamo 1972 na kampuni ya Amerika inayoitwa Digibarn kwa wiring kamili ya mkono. This is a PCB board based on Intel8008 computer. Wiring ya Angle ya kiholela iliyoonyeshwa kwenye Kielelezo 2 ni sawa. Kwa nini watumie wiring ya Angle ya kiholela? Kwa sababu aina hii ya wiring ina faida nyingi. Arbitrary Angle wiring has many advantages. Kwanza, kutotumia pembe kati ya sehemu za laini huokoa nafasi ya PCB (poligoni daima huchukua nafasi zaidi kuliko tangents). Traditional automatic cablers can place only three wires between adjacent components (see left and center in Figure 3). Walakini, wakati wa wiring kwenye Angle yoyote, kuna nafasi ya kutosha kuweka waya 4 kwenye njia ile ile bila kukiuka ukaguzi wa sheria za muundo (DRC). Tuseme tuna chip ya hali nzuri na tunataka kuunganisha pini za chip na pini zingine mbili. Using only 90 degrees takes up a lot of space. Kutumia wiring ya Angle holela kunaweza kufupisha umbali kati ya chip na pini zingine, wakati unapunguza alama ya mguu. 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. Hii sio nadharia tu, bali pia suluhisho la vitendo (wakati mwingine suluhisho pekee linalowezekana). Shows an example of a simple PCB. Matokeo ya cable ya topolojia, wakati matokeo ya kiatomati ya kiotomatiki kulingana na umbo bora ni picha za PCB halisi. An automatic cabler based on optimal shape cannot do this because the components are rotated at arbitrary angles. Unahitaji eneo zaidi, na ikiwa hautageuza vifaa, kifaa kinapaswa kufanywa kikubwa. 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. Ikiwa kuna Angle kati ya sehemu za waya, basi wakati Angle hii inapoongezeka, kiwango cha crosstalk kitapungua. 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. Fikiria njia tatu zifuatazo za wiring. 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. Cabler huhesabu moja kwa moja sura bora ya waya (kwa kuzingatia idhini muhimu ya usalama). Ufungaji rahisi unaweza kupunguza muda unaohitajika kuhariri topolojia, ikiunga mkono vizuri urejeshi mwingi ili kukidhi vizuizi. Hii inaonyesha muundo wa PCB ambao unapita kupitia mashimo na alama za tawi. Wakati wa harakati za moja kwa moja, vidokezo vya tawi la waya na mashimo-hubadilishwa kwa nafasi nzuri. 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. Njia inapopatikana, inarekebishwa na inakuwa sehemu ya maze. Ubaya wa wiring mtiririko ni kwamba matokeo ya wiring yanaweza kutegemea mpangilio wa wiring. Wakati ubora wa mada bado haujakamilika, shida ya “kukwama” hufanyika katika maeneo madogo ya hapa. 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. Kuinama kwa waya kunamaanisha uzushi kwamba waya katika mtandao mmoja lazima itembee karibu na kitu kwenye mtandao mwingine kupata kitu. Rewiring a wire will not correct this. Mfano wa kuinama umeonyeshwa. A lit red wire travels around a pin in the other network, and an unlit red wire connects to this pin. Matokeo ya moja kwa moja ya usindikaji yanaonyeshwa. 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. Waya nyekundu bent ni yalionyesha. Katika mti wa Steiner, mistari yote lazima iunganishwe kama sehemu kwa vipeo (ncha za mwisho na nyongeza). Juu ya kila kitambulisho kipya, sehemu tatu lazima ziungane na hakuna zaidi ya sehemu tatu lazima ziishe. The Angle between the line segments that converge to the vertex shall not be less than 120 degrees. Sio ngumu sana kuunda Steiner na mali hizi za kutosha, lakini sio lazima iwe ndogo. Gray Steiner trees are not optimal, but black Steiner trees are. Katika muundo wa mawasiliano wa vitendo, aina tofauti za vizuizi lazima zizingatiwe. Wanapunguza uwezo wa kujenga miti ya chini ya upana kwa kutumia algorithms zote na miti ya Steiner kwa kutumia njia za kijiometri. 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. Utaratibu kuu hapa ni algorithm inayotegemea nguvu ambayo huhesabu vikosi vinavyofanya kazi kwa vipeo vipya na kurudia kuzielekeza kwenye hatua ya usawa (ukubwa na mwelekeo wa vikosi hutegemea waya kwenye sehemu za tawi zilizo karibu). Ikiwa Angle kati ya jozi ya sehemu za laini zilizounganishwa na vertex (terminus au nyongeza) ni chini ya digrii 120, hatua ya tawi inaweza kuongezwa, na kisha algorithm ya mitambo inaweza kutumika kuboresha nafasi ya 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. Inaruhusu pia maeneo ambayo uunganisho wa vituo vya mwisho ni marufuku, na idadi ya nodi za mwisho zinaweza kuwa za kiholela.

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. Baadhi ya tabaka kwenye mchoro zimeponyoka wiring. Kielelezo 16 kinaonyesha robo ya BGA. Wakati huo huo, wakati wa kutumia njia ya wiring “kituo cha pembezoni”, idadi ya njia zinazohitajika kutoka pembezoni hazibadilika kutoka safu hadi safu. Hii itapunguza sana idadi ya matabaka. Kwa saizi ya sehemu ya 28x28mm, tabaka 7 zinatosha. Kwa vifaa vikubwa, ni kushinda-kushinda. 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. Holela ya angani ya kiufundi ya kiufundi inaweza kufanya hivyo. 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.