How to Find the Right PCB Assembly Factory in China: A Complete Guide

Searching for a PCB assembly factory in China can feel overwhelming. Thousands of factories in Shenzhen alone. Each one claiming to be “the best.” Prices ranging wildly. And you’re thousands of miles away.

After touring multiple facilities in the Pearl River Delta (PRD) – the world’s electronics manufacturing heartland – I’ve put together this practical guide to help you navigate the process.

Here is what we will cover:

  1. What files you need to get an accurate quote

  2. What fabrication processes a capable factory should offer

  3. How to identify which factory is right for you

Let’s dive in.


Part 1: What Files Do You Need for PCB Assembly?

Before any factory can quote or assemble your boards, you must provide a complete documentation package. Incomplete or incorrect files are the #1 cause of delays, incorrect quotes, and assembly errors.

Here is the standard checklist:

Required Files (Every Project Needs These)

File Type Format What It Contains Why It’s Needed
Gerber Files .zip (RS-274X) PCB layer data: copper traces, solder mask, silkscreen, pad locations Fabrication of the bare PCB
BOM (Bill of Materials) Excel/CSV Component list: part number, value, package, quantity, reference designator Sourcing components and assembly planning
Pick & Place (Centroid) File .txt or .csv X/Y coordinates and rotation for every component Tells SMT machines exactly where to place each part
PCB Specification Text/PDF Layer count, dimensions, quantity, thickness, pad finish (HASL/ENIG/OSP), color Defines how the PCB should be manufactured

Recommended Files (Avoid Mistakes)

File Type Format Purpose
Assembly Drawing PDF Shows component orientation, polarity marks, special assembly notes
Schematic PDF Circuit diagram – used for functional test development and debugging
Testing Plan PDF Functional test steps, expected voltages/signals, pass/fail criteria

How to Generate Gerber Files

Gerber files are the industry standard for PCB fabrication. They tell the factory exactly how to manufacture your bare circuit board. Here is how to export them from common EDA software:

Software Export Function Notes
Altium File → Fabrication Outputs → Gerber Files Select all layers (Copper, Solder Mask, Silkscreen, Drill). Use RS-274X format
KiCad File → Plot → Generate Gerber Files Check “Use Protel filename extensions”. Also generate drill files (.drl)
Eagle File → CAM Processor → Load job file → Process Job Use “gerb274x.cam” job file for standard Gerber output
EasyEDA Fabrication Output → Gerber One-click generation. Download as .zip file
OrCAD Manufacture → Artwork → Create Artwork Set format to RS-274X. Generate all layer films
DipTrace File → Export → Gerber Select all necessary layers. Include drill file

What a Gerber package should include:

  • Copper layers (Top, Bottom, Inner 1, Inner 2, etc.)

  • Solder mask layers (Top, Bottom)

  • Silkscreen layers (Top, Bottom)

  • Paste mask layers (Top, Bottom) – for stencil fabrication

  • Drill file (Excellon format)

  • Readme file (layer stackup, dimensions, special instructions)


How to Generate a BOM (Bill of Materials)

The BOM is a complete list of components needed to assemble your board. Accurate BOMs prevent sourcing errors and assembly delays.

Software Export Function Notes
Altium Reports → Bill of Materials Export as Excel (.xlsx) or CSV. Use built-in templates
KiCad File → Fabrication Outputs → BOM Export as .csv or .html. Use plugins for advanced formatting
Eagle Run ULP → bom.ulp Exports as .txt or .csv. Can group identical components
EasyEDA Fabrication Output → BOM One-click export. Includes manufacturer part numbers if available
OrCAD Tools → Bill of Materials Export as .txt, .csv, or .xls
CircuitStudio Reports → Bill of Materials Export to Excel. Customizable columns

What a good BOM should include (minimum):

Column Example Why It’s Needed
Reference Designator R1, R2, C3, U1 Tells factory where to place each component
Part Number (MPN) CRCW040210K0FKED Manufacturer part number – ensures correct component
Value / Specification 10kΩ, 1%, 0402 Electrical and physical specifications
Package / Footprint 0402, SOP-8, QFN-32 Physical size and pad layout
Quantity 100 Total number needed for your order
Description Resistor, chip Quick identification

How to Generate a Pick & Place (Centroid) File

The Pick & Place file tells SMT machines exactly where to put each component on the board.

Software Export Function Notes
Altium File → Assembly Outputs → Generates Pick and Place Exports as .txt or .csv. Includes X/Y coordinates and rotation
KiCad File → Fabrication Outputs → Footprint Position (.pos) Select “Single file for board” and millimeters for units
Eagle ULP → run mountsmd.ulp Generates .txt file with component positions
EasyEDA Fabrication Output → Pick and Place File One-click download. Coordinates in mm or inches
OrCAD Auto → Reports → Place Component Report Export as .txt or .csv
DipTrace File → Export → Pick and Place Select units (mm recommended) and rotation format

What a Pick & Place file should include:

Column Example Purpose
Reference R1 Identifies the component
Layer Top / Bottom Which side of the board
X Coordinate 10.50 Horizontal position in mm
Y Coordinate 25.30 Vertical position in mm
Rotation 0°, 90°, 180°, 270° Component orientation
Package 0402 Footprint size (optional but helpful)

Quick Reference: Files Needed for PCBA

Here is a summary of all files you should prepare before contacting a factory:

File Required? Format Generated By
Gerber files ✅ Yes .zip (RS-274X) PCB design software
Drill file ✅ Yes .drl, Excellon PCB design software (often included in Gerber .zip)
BOM ✅ Yes .xlsx, .csv PCB design software or manual entry
Pick & Place file ✅ Yes .txt, .csv PCB design software
PCB specification ✅ Yes PDF, text Manual – write down layer count, thickness, color, finish
Assembly drawing Recommended PDF PCB design software + manual annotations
Schematic Recommended PDF PCB design software
Testing plan For functional test PDF Manual – describe test steps and pass/fail criteria

Pro tip: Always zip all files together and label the folder with your project name, date, and revision number (e.g., ProjectX_PCBA_v2.1_20250405.zip).


Part 2: What Fabrication & Assembly Processes Should a Factory Offer?

Not all factories are created equal. A capable PCBA factory should offer the following processes. Use this as your checklist when evaluating suppliers.

PCB Types They Should Support

PCB Type Typical Applications Why It Matters
FR4 Rigid Board Standard electronics – consumer, IoT, industrial The baseline – every factory should support this
Aluminum Board LED lighting, power electronics High-thermal applications
Flexible Board (FPC) Wearables, cameras, medical devices Growing demand for compact, bendable designs
Rigid-Flex Board Aerospace, medical implants, high-reliability Complex products that need both rigid and flexible sections

SMT Assembly Capabilities

Package Type What It Means Minimum Capability
Standard passives 0805, 0603, 0402 All factories should handle these
Small passives 0201 (0.6mm x 0.3mm) Good factories support this. Essential for compact designs
IC packages SOIC, QFP, QFN, PLCC Standard – should be supported
Advanced packages BGA, PoP (Package-on-Package) Required for smartphones, advanced processors, memory chips

Through-Hole & Assembly Capabilities

Process Description When You Need It
Through-Hole Assembly Components with leads inserted into holes Connectors, large capacitors, transformers, relays
Wave Soldering Simultaneous soldering of all thru-hole components High-volume thru-hole production
Hand Soldering Manual soldering for rework or small batches Prototypes, touch-up, odd-shaped components
Sub-Assembly Partial assembly – e.g., PCBA mounted into enclosure When you need more than just a bare board
Box Build Assembly Complete product assembly including casing, wiring, labeling Full product manufacturing

Soldering Standards

Standard What It Means
Lead-Free / RoHS Compliant Mandatory for products sold in EU, US, many other markets
IPC-A-610 International standard for PCB assembly acceptability – look for Class 2 (general electronics) or Class 3 (high-reliability for medical/aerospace)

Quality Control & Testing Processes

A professional factory should offer a multi-stage QC process:

Stage Process What It Detects
Incoming IQC (Incoming Quality Control) Damaged or counterfeit components, PCB defects
SMT Line SPI (Solder Paste Inspection) Incorrect paste volume, alignment issues
SMT Line Pre-reflow AOI Missing components, polarity errors
SMT Line Post-reflow AOI Solder bridges, insufficient solder, tombstoning
SMT Line X-Ray Inspection (for BGA/QFN) Hidden voids or shorts under components
Post-Assembly ICT (In-Circuit Test) Shorts, opens, incorrect component values
Post-Assembly Functional Test Board works as designed – powered up and tested
Outgoing OQC (Outgoing Quality Control) Final visual and packing check

Optional Value-Added Services

These services separate good factories from great ones:

Service Why It Matters
Turn-Key Component Sourcing Factory procures all parts – one invoice, one point of contact
Design for Manufacturing (DFM) Review Catches design errors before production – saves time and money
Conformal Coating Protects boards from moisture, dust, chemicals
Flying Probe Test Fixtureless testing – ideal for prototypes and small batches
Drop Shipping Factory ships directly to your end customers

Certifications to Look For

Certification Industry Why It Matters
ISO9001:2015 All industries Basic quality management system – ensures consistent processes
IATF16949:2016 Automotive Strictest quality standard – required for car electronics
ISO13485 Medical devices Quality management for medical products – rigorous traceability
UL / CE / FCC Various Product safety and compliance – factory should have experience with these certifications

Part 3: Which Factory Is the Right One for You?

Now that you know what files to prepare and what processes to look for, here is how to match your specific needs to the right type of factory.

Step 1: Understand Your Own Requirements

Ask yourself these questions before contacting any factory:

Question Your Answer Implication
What is your order quantity? 1–100 units Look for prototype-friendly factories. Avoid high-volume-only factories
100–1,000 units Look for small-batch specialists
1,000–10,000 units Most mid-sized factories can handle this
10,000+ units Look for high-volume factories with multiple SMT lines
What is your PCB technology? FR4, simple design Most factories qualify
Flex, rigid-flex, HDI Need a factory with advanced capabilities
What components are you using? 0402, 0201, BGA, PoP Need a factory with advanced SMT equipment
Through-hole connectors Need a factory with wave soldering capability
What certifications do you need? ISO9001 only Most certified factories qualify
IATF16949 (automotive) Need automotive-certified factory
ISO13485 (medical) Need medical-certified factory
Who provides components? You supply all parts Look for factories with no handling fee for customer-supplied parts
Factory supplies all parts Need a factory with strong turn-key sourcing capabilities
Do you need testing? Just visual inspection Basic QC is sufficient
Functional testing, ICT, X-Ray Need a factory with advanced testing equipment

Step 2: Match Your Needs to Factory Types

Here is a simple decision matrix:

Your Profile Recommended Factory Type What to Look For
Hardware startup / Maker (1–100 units, simple FR4, tight budget) Prototype-focused small factory Low MOQ (1–5 pcs), accepts customer-supplied parts, quick turnaround, no handling fee
SMB / Growing brand (100–5,000 units, mixed components) Mid-sized factory with flexible lines Dedicated project manager, turn-key option, functional testing, ISO9001
Medical device company (Low volume, high reliability) ISO13485 certified factory Class 3 IPC-A-610, full traceability, X-Ray, burn-in testing, documentation package
Automotive supplier (Medium to high volume) IATF16949 certified factory PPAP documentation, strict process control, 100% testing
High-volume consumer electronics (50,000+ units, cost-sensitive) Large factory with multiple SMT lines Economies of scale, automated testing, wave soldering for thru-hole

Step 3: Red Flags to Watch Out For

During your factory evaluation, watch for these warning signs:

Red Flag Why It’s a Problem
“We can do everything” without asking for your files No factory is good at everything. They should ask questions about your specific needs
No clear quality control process If they can’t explain their QC steps, they probably don’t have them
No certifications displayed or offered ISO9001 is basic. If they don’t have it, walk away
Vague pricing You should get a line-item quote: PCB + stencil + components + assembly + testing
No dedicated project manager You will waste time chasing different people for updates
Push back on small orders If they say “minimum 10,000 units” and you need 100, find another factory

Step 4: The Reality of Remote Sourcing

Here is the honest truth:

You cannot verify a factory’s quality from your desk.

Photos on websites can be outdated. Samples can be perfect while mass production cuts corners. Claims of “ISO certification” might be fake.

Even after you match all the criteria above, you still need someone on the ground to:

  • Conduct an in-person factory audit before you commit

  • Perform in-process inspections during your production run

  • Verify pre-shipment quality before your boards leave China


How We Help: Your Local Partner in Shenzhen

You don’t need to fly to China to get factory-floor visibility. We are based in Shenzhen, and we act as your local eyes and ears.

What We Do

Service What You Get
Factory Sourcing We match your requirements (quantity, PCB type, components, certifications, budget) to 3–5 qualified factories from our vetted network of 500+ suppliers
Factory Audit On-site evaluation within 24–48 hours – we verify equipment, ESD controls, certifications, staff competency, and take photo/video evidence
Production Follow-Up We monitor first article inspection, check component placement, verify BOM compliance, and send real-time updates via WhatsApp/WeChat
Pre-Shipment Inspection AQL Level II sampling per ANSI/ASQ Z1.4, IPC-A-610 Class 2 or 3 visual check, functional test verification, packing check
Full Transparency Detailed report with photos and videos. Live video call during any inspection – you watch from your office

What We Cover

We serve the entire Pearl River Delta electronics manufacturing region:

City Response Time
Shenzhen Same-day
Dongguan Same-day
Huizhou Same-day
Guangzhou 24–48 hours
Foshan 24–48 hours
Zhuhai 24–48 hours
Zhongshan 24–48 hours
Jiangmen 24–48 hours

Our Commitment

  • No hidden fees – transparent per-service or percentage-based pricing

  • Electronics specialists – we understand PCBA, components, assembly, and certifications like CE, FCC, RoHS

  • One point of contact – we coordinate with suppliers so you don’t have to

  • English and Chinese support – no language barriers


Summary: Your Action Plan

Here is a quick checklist to guide your next steps:

Step Action
1 Prepare your files – Gerbers, BOM, pick & place, PCB spec, testing plan (if available)
2 Define your requirements – quantity, PCB type, components, certifications, budget
3 Identify your factory type – prototype, SMB, medical, automotive, or high-volume
4 Contact us for factory matching – we will find 3–5 qualified suppliers from our vetted network
5 Review audit reports – we visit the factories and send you photo/video evidence
6 Approve production – we monitor quality throughout the process
7 Receive your boards – with confidence, knowing we verified quality on the ground

Ready to Find the Right PCB Assembly Factory?

Stop guessing. Stop worrying about hidden defects.

👉 Click here to work with your local partner in China’s electronics hub

Get:

  • ✅ Precision factory matching (3–5 qualified suppliers based on YOUR needs)

  • ✅ On-site audits within 24–48 hours

  • ✅ Production follow-up and pre-shipment inspection

  • ✅ Full transparency with photos, videos, and live calls

Free consultation – no obligation.

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