Kukufundisha kubuni PCB na sura isiyo ya kawaida

Tunatarajia nini kamili PCB is usually a neat rectangular shape. Ingawa miundo mingi ni ya mstatili, nyingi zinahitaji bodi zilizo na maumbo ya kawaida, ambayo sio rahisi kila wakati kuunda. This paper introduces how to design PCB with irregular shape.

Leo, PCBS zinapata kazi ndogo na zaidi na zaidi zinaongezwa kwenye bodi, ambazo, pamoja na kuongezeka kwa kasi ya saa, hufanya miundo kuwa ngumu zaidi. Kwa hivyo, wacha tuangalie jinsi ya kushughulikia bodi ya mzunguko na sura ngumu zaidi.

As figure 1 shows, simple PCI board shapes can be easily created in most EDA Layout tools.

Kielelezo 1: Muonekano wa bodi ya kawaida ya mzunguko wa PCI.

Walakini, wakati maumbo ya bodi yanahitaji kubadilishwa kwa mabanda tata na mapungufu ya juu, sio rahisi kwa wabuni wa PCB kwa sababu kazi katika zana hizi sio sawa na zile zilizo kwenye mifumo ya mitambo ya CAD. The complex circuit board shown in Figure 2 is designed primarily for explosion-proof housing and is subject to many mechanical limitations. Trying to reconstruct this information in EDA tools can take a long time and be unproductive. Inawezekana kwamba mhandisi wa mitambo tayari ameunda makazi, sura ya bodi ya mzunguko, eneo la shimo linaloweka, na mipaka ya urefu inayohitajika na mbuni wa PCB.

Kielelezo 2: Katika mfano huu, PCB lazima iliyoundwa iliyoundwa kulingana na uainishaji maalum wa mitambo ili iweze kuwekwa kwenye vyombo visivyo na mlipuko.

Kwa sababu ya radians na radii kwenye bodi ya mzunguko, ujenzi unaweza kuchukua muda mrefu kuliko inavyotarajiwa, hata ikiwa sura ya bodi ya mzunguko sio ngumu (kama inavyoonyeshwa kwenye Kielelezo 3).

Kielelezo 3: Kubuni radians nyingi na curve tofauti za radius inaweza kuchukua muda mrefu.

These are just a few examples of complex circuit board shapes. However, from today’s consumer electronics, you’d be surprised how many projects try to cram all the functionality into a small package that isn’t always rectangular. Smartphones and tablets are the first things that come to mind, but there are plenty of examples.

Ukirudisha gari la kukodisha, unaweza kuona mhudumu akitumia skana ya mkono kusoma habari za gari na kisha kuwasiliana bila waya na ofisi. The device is also connected to a thermal printer for instant receipt printing. Karibu vifaa hivi vyote hutumia bodi za mzunguko ngumu / rahisi (Kielelezo 4), ambapo bodi za kawaida za PCB zimeunganishwa na mizunguko iliyochapishwa rahisi ili iweze kukunjwa kwenye Nafasi ndogo.

Kielelezo 4: Bodi ya mzunguko ngumu / rahisi inaruhusu matumizi ya juu ya nafasi inayopatikana.

Swali, basi, ni “Je! Unaingiza vipi uainishaji wa uhandisi wa mitambo katika zana ya muundo wa PCB?” Kutumia tena data hii katika michoro za kiufundi huondoa kurudia kwa juhudi na, muhimu zaidi, kosa la mwanadamu.

Tunaweza kutatua shida hii kwa kuagiza habari zote kwenye programu ya Mpangilio wa PCB kwa kutumia muundo wa DXF, IDF au ProSTEP. Hii inaokoa wakati mwingi na inaondoa uwezekano wa makosa ya kibinadamu. Next, we’ll take a look at each of these formats.

Graphics interchange format – DXF

DXF ni moja ya fomati kongwe na inayotumiwa sana kwa kubadilishana data kwa njia ya kielektroniki kati ya vikoa vya mitambo na PCB. AutoCAD ilitengeneza mapema miaka ya 1980. Fomati hii inatumiwa haswa kwa ubadilishaji wa data mbili. Wauzaji wengi wa zana za PCB wanaunga mkono muundo huu, na inarahisisha ubadilishaji wa data. Uagizaji / usafirishaji wa DXF unahitaji utendaji wa ziada kudhibiti matabaka, vyombo tofauti na vitengo ambavyo vitatumika katika mchakato wa ubadilishaji. Figure 5 is an example of importing very complex circuit board shapes in DXF format using Mentor Graphics’ PADS tools:

Figure 5: PCB design tools (such as PADS described here) need to be able to control the various parameters required using DXF format.

A few years ago, 3d functionality began to appear in PCB tools, and there was a need for a format that could transfer 3D data between machines and PCB tools. Kutoka kwa hii, Mentor Graphics ilitengeneza muundo wa IDF, ambayo imekuwa ikitumika sana kuhamisha bodi ya mzunguko na habari ya sehemu kati ya PCBS na zana za mashine.

Wakati muundo wa DXF una ukubwa wa bodi na unene, fomati ya IDF hutumia nafasi za X na Y za sehemu, nambari ya sehemu, na urefu wa z-mhimili wa sehemu hiyo. This format greatly improves the ability to visualize a PCB in a 3D view. Additional information about forbidden areas, such as height restrictions on the top and bottom of the board, may also be included in the IDF file.

Mfumo unahitaji kuweza kudhibiti kile kitakachomo kwenye faili ya IDF kwa njia sawa na Mipangilio ya parameter ya DXF, kama inavyoonyeshwa kwenye Kielelezo 6. Ikiwa vifaa vingine havina habari ya urefu, mauzo ya nje ya IDF yanaweza kuongeza habari iliyokosekana wakati wa uundaji.

Figure 6: Parameters can be set in the PCB design tool (PADS in this example).

Faida nyingine ya kiolesura cha IDF ni kwamba chama chochote kinaweza kusonga sehemu kwenda mahali kipya au kubadilisha umbo la bodi, na kisha kuunda faili tofauti ya IDF. Ubaya wa njia hii ni kwamba unahitaji kuagiza tena faili nzima inayowakilisha mabadiliko kwenye bodi na vifaa, na katika hali zingine inaweza kuchukua muda mrefu kwa sababu ya saizi ya faili. In addition, it can be difficult to determine from the new IDF file what changes have been made, especially on larger boards. Users of IDF can eventually create custom scripts to determine these changes.

HATUA na ProSTEP

Ili kusambaza vizuri data-dimensional tatu, wabuni wanatafuta njia iliyoboreshwa, muundo wa STEP ulitengenezwa. Fomati ya STEP inaweza kusambaza vipimo vya bodi ya mzunguko na mipangilio ya vifaa, lakini muhimu zaidi, vifaa havina sura rahisi na tu urefu wa urefu. Mfano wa sehemu ya STEP ni uwakilishi wa kina na ngumu wa vifaa katika hali ya pande tatu. Both circuit board and component information can be transferred between the PCB and the machine. Walakini, bado hakuna utaratibu wa kufuatilia mabadiliko.

Ili kuboresha ubadilishaji wa faili wa STEP, tulianzisha muundo wa ProSTEP. This format moves the same data as IDF and STEP and has a big improvement – it can track changes and also provide the ability to work within the discipline’s original systems and review any changes once a baseline has been established. In addition to viewing changes, PCB and mechanical engineers can approve all or individual component changes in layout, board shape modifications. They can also suggest different board sizes or component locations. This improved communication creates an ECO (Engineering Change Order) between ECAD and the mechanical team that never existed before (Figure 7).

Kielelezo 7: Pendekeza mabadiliko, angalia mabadiliko kwenye zana asili, idhinisha mabadiliko, au pendekeza tofauti.

Leo, mifumo mingi ya ECAD na mitambo ya CAD inasaidia matumizi ya fomati ya ProSTEP kuboresha mawasiliano, kuokoa muda mwingi na kupunguza makosa ya gharama kubwa ambayo yanaweza kusababisha muundo tata wa elektroniki. Kwa zaidi, wahandisi wanaweza kuokoa wakati kwa kuunda sura tata ya bodi ya mzunguko na vizuizi vya ziada na kisha kusambaza habari hiyo kwa njia ya kielektroniki ili kuzuia mtu kutafsiri vibaya vipimo vya bodi ya mzunguko.

hitimisho

Ikiwa haujatumia yoyote ya aina hizi za DXF, IDF, STEP, au ProSTEP kubadilishana habari, unapaswa kuangalia matumizi yao. Fikiria kutumia edi hii kuacha kupoteza wakati kurudia maumbo ya bodi ngumu.