Mai i nga huringa tauira i runga i nga papa faraoa tae noa ki te hoahoa i a maatau ake te papa poari panui (PCBS), it was like getting off the training wheels. There’s a lot to learn about this process, so let’s get started. Ko te hoahoa PCB e mahia ana i roto i te mahinga hangarau hiko (EE). Ka hangaia e te EE te “roro” mo te mahinga o nga taputapu. Without electronics, you’re left with little more than a pile of metal and plastic.

Things to know before starting PCB design: 1. PCB size – this depends on your product size (or case size). Ko nga waahanga hua e tautuhia ana i te wa o te mahinga hoahoa hangarau hiko. Ka taea e koe te maataki i tetahi riipene whakaata i konei. 2. Paparanga PCB – Ko te maha o nga papa, ko te uaua o te MANUFACTURE o PCB. (Panui: Ahakoa ko te PCB paparanga kotahi he PCB uaua tonu, engari kei konei e korero ana taatau mo te uaua o te hanga PCB. Ka nui ake nga papa o te PCB, ka nui ake te utu ki te mahi.)

Layer 2 is usually used for simple toy products

Ko nga hua e pa ana ki te Iot te tikanga e 4 nga papa

Typically used for floors 6 to 8 of a smartphone or smartwatch.

3. Your PCB manufacturer’s requirements. Be sure to read the guidelines for rhythm, trace size, power isolation, and file naming before you start designing.

Nga korero e hiahia ana koe ki te whakarato ki nga kaiwhakanao PCB:

Number of layers (e.g. 2, 4, 6, etc.)

Rauemi (FR-2 (pepa miro phenolic), FR-3 (pepa miro me te epoxy), FR-4 (karaihe muka me te epoxy… Etc.)

Thickness (0.5 mm, 1.0 mm… Etc.)

Color (red, black, green… Etc.)

Maimoatanga o runga (ENIG (nika / rumaki koura), DIG (rumaki koura totika), OSP (nga rauropi whakarewa waatea, me etahi atu)

Copper weight (1 oz (35 microns), 2 oz (70 microns), 0.5 oz (18 microns)… Etc.)

Kōnae Gerber

PCB design process:

Hoahoa porowhita

For this step, you need to create the schematic. This is a document, like a blueprint, that describes how components relate to each other and work together. To create the schematic file, you will need a software tool. He pai ki a matou a Quadcept na te mea kua aroturukihia mo te hoahoa PCBS mo te whakangao (hei tauira, ka taea te kawe tika i tetahi Pire Rauemi (BoM) mai i te taputapu) ana he kapua, na reira ka ngawari te whakamahi i nga waahi katoa. (They also offer a free community version of the tool for manufacturers and students.)

There are many other options you can choose from:

Altium

ExpressPCB

Pūrere auau

KiCad

Cadence allegro

moenga

Hoahoa awhina rorohiko

PanuiTohu

After you install the selected tools, you need to obtain the component specifications for each selected component. They can often be found on the supplier’s website. Ma te konae tauira te awhina i a koe ki te tuhi i te kaupapa. This component becomes available in the database when you upload the model to the software tool. Then, all you have to do is follow the data manual and connect the wire to each pin in the component. (Panui: ko nga korero mo te mahinga hoahoa ka whakawhirinaki ki te taputapu raupaparorohiko kua tohua).

Each schematic symbol needs to have an associated PCB space area to define the physical dimensions of the component and the location of the through holes on the brazing pad or PCB. You should have selected the components (or are now selecting them), and we describe this process in the EE Design Process video (see video).

Example diagram

A good schematic is really important, as it will be used as a reference document during debugging and is a good communication tool with other engineers. Hei taapiri, ka taea e te kaiwhakanao te whakamatautau i te taputapu ma nga tohu whakamatautau o tenei tuhinga.

PCB layout + Gerber file

To design the PCB layout and create Gerber files, you can use the same software tools we mentioned in circuit design. Kaore i te ahua o te kaupapa, he whakatakotoranga PCB ka toha i nga waahanga tuuturu ki nga waahi tika i runga i te PCB me te whakaatu i nga riu e hono ana i ia waahanga i waenga i nga waahanga PCB. As mentioned at the beginning of this article, the more layers, the more complex the manufacturing required, and the higher the cost.

Divide the PCB into logical parts based on functions (e.g. power supply, audio output, etc.). Then, be sure to group the components of each section into the same area. Ma tenei, ka taea e koe te pupuri i te ara arai poto me te whakaiti i te haruru me te pokanoa.

Ko te mahinga kaiwhakamahi (UI) me mahara ano i te wa e hangaia ana e koe tetahi PCB. Ko nga waahanga penei i nga puoro oro, honohono, rama, me etahi atu me whakatika kia tutuki pai ai te wheako kaiwhakamahi.

Once the layout is designed, a Gerber file is generated. Ka whakamahia e to kaiwhakanao PCBA tenei konae. There are many companies that offer these services, and from HWTrek’s expert library we recommend Kingbrother, NexPCB, and HQPCB.

Sample Gerber files

Ko te whakanoho i nga waahanga ki te PCB he mea nui. Some components can interfere with each other and cause unexpected behavior. For example, if you have both Bluetooth and Wi-Fi modules, they have the same 2.4ghz bandwidth and can interfere with each other if incorrectly placed.

PCB production

When you send the Gerber file to the PCB manufacturer, they can print the board. Koinei te maatauranga ki te hanga ake i te turanga mo te taapiri i nga waahanga ki te PCB me te hanga i te PCBA (huihuinga poari ara iahiko).

Unassembled PCBS

PCBA (Assembly)

Te whakareri rauemi

I tenei wa i roto i to hoahoa EE, kua tohua e koe nga waahanga. You can ask the PCBA manufacturer to order the required components for you, or do it yourself if you choose a supplier. He mea nui e hiahiatia ana:

Lead time: As these components come from different suppliers, keep the lead time in mind. For some components, it can take up to 8-16 weeks.

Packaging: Order components from reels that are automatically picked up by SMT machines instead of packaging them individually.

Te rahinga ota iti: Tirohia te rahinga ota iti mo te waahanga. Mena ka hokona e koe i raro iho i te mea iti, tirohia nga waahanga kua tohua. For small batches (up to 50), you can order online from DigiKey or Mouser. Mo etahi atu waahanga, tena koa rapu tohutohu mai i to kaihanga.

Loss: Order 10% more to cover loss (not for expensive components)

Install components on the PCB

There are two main ways to place components on a PCB surface:

Through-holes (through-holes) are manual methods of assembling assemblies with wires into holes on the surface of a PCB. It is also commonly known as DIP or dual in-line packaging process. (See SMT in progress in this video)

Ko te SMT (hangarau maunga mata) te tikanga tino whanui i te mahinga papatipu. It is done by fast, accurate SMT machines that save you time, money and avoid human error.

Nga mea hei mahara:

Your component type number must not exceed the number of reels that the manufacturer’s SMT machine can support.

Optimize and consolidate your components so that only one SMT runs.

Check manufacturer supported footprint pad sizes. Otherwise, the SMT machine will not install components correctly.

Some larger components cannot be installed by machine and still require manual through-hole work. Therefore, both technologies can be used on the same board.

Any components you need to manually add via the through-hole method add to the manufacturing cost.

Rewa rewa

Reflow soldering is the process of making components “stick” to the PCB. Ka whakamanahia e te PCBA te papa ara iahiko na roto i te oumu hou, i te rama pura ranei kia rewa noa te reima, ka mau tonu i te waahanga ki te papa ara iahiko.

The trickiest part here is not to overheat or damage the components, because the thermal characteristics of each package are different. Ko te kaiwhakanao PCBA pono te kawenga mo tenei mahi, ana ko taau noa e whakarato ana he waahanga waahanga.

Tukanga Whakatika.

Other welding methods:

Ko te rewa ngaru te nuinga e whakamahia ana mo nga waahanga taapiri-a-ringa ma te tikanga puta-poka. I tenei keehi, ka haere tuatahi to PCBA ki roto i te oumu whakaoho hurihuri, katahi ka taapirihia etahi atu waahanga i muri i te waa ka uru ki roto i te miihini miihini ngaru.

Ka taea te whakamahi i te maitai maitai mo nga ahuatanga motuhake, engari kaua mo te mahi papatipu.

Te whakamatautau me te tirotiro kounga

I tenei waahanga, ka whakamatautauhia nga tauira PCBA kia pai ai te kounga. Ko nga he noa: ko nga ara iahiko poto kei nga waahanga kua honoa, nga waahanga pohehe me nga waahanga o te ara iahiko kaua e hono. Nga whakamatautau noa:

ICT (Whakamatau Ipurangi). When designing a PCB, some test points are usually reserved for debugging, programming, and other purposes. Ka whakamahia e te miihini ICT enei tohu whakamatautau mo te whakamatautau tuwhera / poto i te ara iahiko poto ka tirohia ko nga uara o nga waahanga hāngū (parenga, whakaurunga, pūnga) kei roto i te whānuitanga whakatakotoranga.

AOI (Tirohanga whatu aunoatia). Manufacturers use a “gold sample” (reference PCBA) to compare with other samples. Mo tenei whakamatautau, me whakarato e te kaihanga taputapu nga whakaritenga me nga manawanui ki te kaiwhakanao ki te whakarite i nga waahanga.

X hihi. The PCBA manufacturer will use X-rays to check the welding conditions of the BGA (ball Grid Array) components. Tirohia te whakamatautau X-hihi i roto i tenei riipene.