PCB Assembly and Electronic Manufacturing: Frequently Asked Questions

PCB assembly (PCBA, Printed Circuit Board Assembly) is the placement and soldering of electronic components onto a printed circuit board using surface-mount (SMD) and through-hole (THT) methods. The result is a board with its components mounted, ready to work.

At the facility in Maslak, Istanbul, SMT Labs runs an automated line from prototype to volume production. The flow is solder-paste printing, SPI, high-speed pick & place, multi-zone reflow soldering and post-placement AOI.

• SMD: from 0201 and 01005 packages to QFN, QFP and BGA/µBGA
• THT: connectors, relays, power parts; selective and hand soldering
• Single and double-sided boards in one flow

In SMD (surface-mount) assembly, components are placed on the board surface and soldered in a reflow oven; it is ideal for small packages, high density and automation. In THT (through-hole) assembly, component leads pass through holes in the board and are soldered; it is preferred for mechanically loaded connectors, relays and power parts.

Most modern boards are mixed. SMT Labs combines SMD and THT on the same board in a single order, with THT supported by selective and hand-solder stations.

Our placement range runs from the 0201 package to BGA and µBGA. Very small passives such as 01005, and fine-pitch parts such as QFN, QFP and LGA, are placed as standard.

Solder quality under hidden-connection parts such as BGA and µBGA is checked by X-ray; a reball is applied where needed.

Yes. We work across every volume range, from a single prototype to low-volume series and high-volume production. The target lead time for sample boards is about 10 business days.

Prototype and series run on the same line with the same parameters, so a design proven in the prototype moves to series production without surprises.

We supply printed circuit boards from one to 64 layers. Materials include standard FR4, high-Tg FR4, aluminium-backed (MCPCB) for heat dissipation, and flex / rigid-flex for bendable applications.

Surface finishes include HASL, lead-free HASL, ENIG and HDI. When you combine PCB fabrication with assembly and component sourcing, a single Gerber + BOM submission returns an assembled board.

The assembly price is not set from a fixed list but calculated with project-specific parameters. Once you send your Gerber, BOM and Pick & Place files, we return an exact price and lead time within 24 hours.

The main factors that drive the price:

• Board quantity (unit cost drops sharply in series production)
• Component count and variety (many different packages mean more feeder changes and setup time)
• SMD / THT ratio, fine pitch and BGA density
• Single or double sided, stencil need
• Leaded / lead-free solder profile
• Extra quality control such as AOI, X-ray, ICT or functional test

No. PCB assembly and fabrication require a multi-variable calculation based on quantity, layer count, component type, test scope and lead time, so we do not publish a fixed price list. Each project is quoted separately from your files.

If your files are complete, your price and lead-time quote is sent within 24 hours. In the same window our engineering team also reviews the Gerber and BOM for DFM and reports any risky points with the quote.

For prototypes and low-volume work, one-time fixed costs such as stencil making, writing the placement program and setting up feeders are divided across a small number of boards, which raises the unit price. As quantity grows, these fixed costs spread out and the unit cost drops quickly.

Yes. If you consign the components, the quote covers only the assembly labour and any stencil / setup fee; no material cost is added. If you hand us the BOM, we take on sourcing original parts from three continents and the material cost is included in the quote.

A mixed model is also possible: you send the critical parts, we source the rest.

The fastest route is to send the Gerber + BOM + Pick & Place files and the target quantity. If you have no design files yet, we can give an indicative price from clear photos of the existing board, an approximate component count and the quantity.

Three files are enough: Gerber for board fabrication and stencil, an LCSC-compatible BOM for the component list, and a Pick & Place (CPL) file for placement coordinates.

Including a fab drawing in the Gerber package, and providing stackup, impedance requirement and quality class (Class 2/3), speeds up the quote.

If files are missing, we derive what we can from the existing board and report the gaps with DFM notes. If there is no Pick & Place, coordinates can be derived from the Gerber and BOM; in that case an extra verification step is added.

Send the BOM as Excel (.xlsx) or CSV, with each row containing the reference designator, manufacturer part number (MPN), package and quantity. Adding the LCSC part number speeds up sourcing and finding alternatives.

The process runs in four steps:

• 1. Send the files: Gerber, BOM and Pick & Place (or a photo of the existing board and the quantity).
• 2. Quote in 24 hours: DFM notes, price and lead time.
• 3. Approval and sourcing: PCB, stencil and component supply; an approved alternative for out-of-stock parts.
• 4. Production and shipping: assembly, AOI and testing are completed; boards ship from the Istanbul central warehouse across Turkey.

Yes. The stainless-steel stencil needed for solder-paste printing is made in-house from your Gerber data. For prototype work the stencil cost appears in the quote as a one-time setup cost.

You can send your panel data or leave the assembly-ready panelisation to us. The panel decision (v-cut, tab-route, edge rails, fiducials) is confirmed in the DFM report.

Yes. We start the conversation with whatever documentation you have. If the design is incomplete, the engineering support team clarifies the gaps (component selection, footprint, DFM), then we move to production. If you prefer, we run PCB, components, assembly, firmware loading and test as a single turnkey project.

Yes. When you send the BOM, we source every part from original suppliers through a network across three continents. Each BOM line is priced by MPN and quantity; stock, lead time and price come back in one table.

If a part is out of stock or its lead time delays the project, we propose an approved alternative MPN that is equivalent electrically, mechanically and in footprint, and report the impact (price, lead time). You make the call; no part is changed without your approval.

Sourcing is done from authorised distributors and verified sources. Source and batch information is shared on request; moisture-sensitive devices are stored and handled dry, per MSL rules.

Import, customs clearance, origin and conformity paperwork run on the SMT Labs side, so long and variable customs processes leave your agenda. The quote shows part cost, freight, customs and related taxes as separate, transparent line items.

Yes. We can source the components and deliver them to you. But when sourcing and assembly are combined, the risk of missing parts, wrong packaging and moisture/ESD handling is managed in one place, with responsibility at a single point.

Quality control is built into the production flow. Post-print SPI (solder-paste inspection) and post-placement AOI (automated optical inspection) are standard; X-ray for connections under BGA/µBGA, and ICT and functional test for electrical verification, are offered as options.

• SPI: paste volume and alignment
• AOI: placement, polarity, solder quality
• X-ray: solder under BGA/µBGA
• ICT / functional test: electrical and functional verification

Production follows the IPC-A-610 Class 2 and Class 3 acceptance criteria. The class is chosen by the board's application: Class 2 for general industrial products, Class 3 for uses where uninterrupted performance is critical (defence, aerospace, medical).

Connections under hidden-connection parts such as BGA and µBGA are imaged by X-ray; voids, bridging and open circuits are caught this way. If a fault is found, a reball is applied and the result is re-verified by X-ray.

Yes. Production is recorded at batch level and, where needed, at component level; which lot-numbered part went onto which board is traceable back. This makes root-cause analysis possible for field issues.

Our quality management approach aligns with ISO 9001, environment with ISO 14001, occupational health with ISO 45001 and information security with ISO 27001; material compliance follows RoHS and REACH. Accredited certificates will be added to the quality policy page as they are issued.

Yes. The outputs of AOI and the selected electrical/functional tests are shared with the shipment on request. The test scope is defined at the quote stage.

Yes. Production takes place at the facility in Maslak, Istanbul; boards are packed and shipped anywhere in Turkey with the courier you choose. Sample and series deliveries are managed from one address.

The target lead time for sample boards is about 10 business days. The exact date is stated in the quote based on component availability, panel structure, test scope and board complexity.

Boards are packed in ESD-protected bags and boxes; boards carrying moisture-sensitive parts get dry packing per MSL rules. Custom labelling and serial-number registration are done on request.

Consolidation, import and customs clearance of parts bought from overseas suppliers are within our logistics service. Parts from different sources are merged at one point and sent as a single shipment, so lead time and cost stay predictable.

In piece-by-piece (partial) service you coordinate PCB, components, assembly and box-build. In turnkey, SMT Labs takes on that coordination, the fit risk and single-lead-time delivery; PCB fabrication, component sourcing, SMD/THT assembly, firmware loading, functional test and box-build are brought into one project plan.

Yes. A mutual non-disclosure agreement is signed with customers who request it; design files, BOM and production data are kept accessible only to the relevant team, for the duration of the project.

We work where reliability and precision are critical: defence, aerospace, automotive and transport, communication technologies, robotics and automation, energy and power electronics, medical and consumer electronics.

Yes. We run contract electronics manufacturing (EMS) agreements with repeatable processes. The sample batch is simplified with DFM feedback, the approved design moves to series with the same parameters, and revisions are tracked with a version record.

SMT Labs operates within SMT Global Mühendislik A.Ş. in Maslak, Istanbul (Giz 2000 Plaza). Our team has more than 15 years of hands-on experience in electronic manufacturing and import; that experience shows up as the right DFM and process decisions, and production that is right the first time.

For a quote, upload your Gerber, BOM and Pick & Place files through the form on our contact page; price and lead time come back within 24 hours. Phone, email and WhatsApp details are on the same page.