How to quote and order PCB assembly

How to quote and order PCB assembly

/在： /通过：
 

When electronic companies look for a PCB manufacturer, one key consideration is pricing. Naturally, companies aim to find a PCB assembly factory with the most suitable price, which helps save significant production costs. But what qualifies as the right price? Understanding the entire PCB assembly quotation process provides the answer. This article explains how PCB assembly is priced and how to complete an order.

What Determines PCB Assembly Costs?

  • PCB Manufacturing Costs
    The quote typically starts with the cost of manufacturing the PCB itself. This includes fees related to producing the bare board, which can vary based on factors such as the number of layers, board size, and material type.

  • Component Costs
    Component costs refer to the prices of all the electronic parts that will be mounted on the PCB. This includes resistors, capacitors, integrated circuits, connectors, and other components specified in the design. Prices fluctuate based on market supply, quantity, and component specifications.

  • Assembly Costs
    Assembly costs cover the labor and equipment needed to place and solder components onto the PCB. This can include surface-mount technology (SMT), through-hole soldering, and any specialized processes required for the specific circuit board design.

  • Testing and Inspection
    Testing and inspection costs ensure that the assembled PCBs meet quality and performance standards. This may involve automated optical inspection (AOI), functional testing, and other quality control measures. The complexity of testing and the scope of inspections affect the overall cost.

  • Tooling and Setup Fees
    These fees account for the initial setup costs of the assembly process, including creating solder masks, programming pick-and-place machines, and other preparatory work. Setup costs are usually one-time charges, but they can vary depending on the board’s complexity and the production volume.

  • Additional Services
    Additional services may include packaging, shipping, and any value-added services such as custom labeling or conformal coating. These costs are typically listed separately in the quotation.

Documents Required for Obtaining a PCBA Quote

When requesting a PCBA quote, it’s typically necessary to provide a set of essential documents to ensure the accuracy of the quotation and smooth production. Below are some commonly required documents:

  1. Bill of Materials (BOM):
    The BOM is indispensable for a PCBA quote. It lists all the components on the PCB, including their names, models, quantities, and supplier information. The BOM helps suppliers accurately calculate material costs and ensure the correct components are procured.

  2. Gerber Files:
    Gerber files are exported from PCB design software and contain information about the PCB’s circuit layers, solder mask, stencil, pads, and silkscreen. These files are the foundation for PCB manufacturing and assembly, guiding the supplier in producing the bare board and setting up the assembly process.

  3. Assembly Drawings:
    Assembly drawings provide detailed instructions for PCB assembly, including the placement of components, polarity, and soldering methods. Any special assembly requirements or change notifications should also be noted in the assembly drawings.

  4. Dimensions for Non-Standard Components:
    For non-standard components, size specifications may need to be provided to ensure proper assembly. This information helps suppliers avoid errors during assembly and maintain product quality and reliability.

  5. Software Design Files (if applicable):
    If the PCBA involves embedded systems or software programming, relevant software design files, such as source code and compiled configurations, may be required. These files assist suppliers in understanding the software’s functionality and performance requirements for appropriate testing and verification.

  6. 3D PCBA Model Files (if applicable):
    In some cases, a 3D PCBA model file may be needed to assess dimensions and assembly. These files help suppliers better understand the product’s structure and assembly requirements during design and production.

Factors Influencing PCB Assembly Costs

The process of assembling electronic components onto a PCB to create a functional device is known as printed circuit board assembly (PCBA). Variables such as PCB size and complexity, quantity and caliber of components, volume, and testing requirements are just a few factors that affect PCBA costs.

  1. PCB Size and Complexity
    The size and complexity of the PCB are primary determinants of PCBA costs. Larger boards require more resources and processing time, thus increasing production costs. Additionally, producing PCBs with more layers, intricate designs, or special materials demands more expensive manufacturing processes.

  2. Component Type and Quantity
    The type and quantity of components used in the PCBA process significantly influence overall costs. Through-hole components are generally less expensive than high-end parts that utilize surface-mount technology (SMT), such as ultra-small chips or ball grid arrays (BGA). The more components used in assembly, the higher the total cost.

  3. Assembly Technology
    PCBA prices can vary based on the assembly method employed. Manual assembly is more costly than automated processes because it requires more time and labor. In contrast, automated techniques such as pick-and-place machines and SMT reduce costs while improving efficiency.

  4. Manufacturing Volume
    The required production volume is a key cost factor. Unit costs decrease as quantity increases, because fixed expenses are spread across a larger number of units, lowering the per-unit cost.

  5. Testing Requirements
    Costs can fluctuate based on the testing specifications for the PCBA. Testing is a critical step to ensure that the final product meets necessary standards. For example, in-circuit testing (ICT) and functional testing (FCT) are more expensive than simpler techniques like visual inspections. Additionally, more rigorous testing requirements may extend production time, which can further raise overall costs.

  6. Packaging Costs
    Another factor affecting PCBA costs is packaging, particularly the packaging requirements for various electronic components. For instance, BGAs require more time and precision to package, as they must be carefully connected to power supplies. Furthermore, BGAs often need X-ray inspection to check for issues such as short circuits, which increases assembly costs.

  7. Labor Costs by Region
    Labor costs vary by region, which significantly impacts PCBA costs. For example, assembly services in low-cost countries can save around 50% on labor costs. However, when choosing labor from other countries, it’s crucial to consider the level of PCBA assembly expertise, especially for more complex projects such as multilayer PCBA.

  8. Lead Time
    PCBA costs may vary depending on the required delivery time. If a manufacturer needs to prioritize an order and allocate more resources to meet a tight deadline, the overall price may increase. Conversely, longer lead times provide manufacturers with more flexibility, potentially reducing costs.

Steps for Quoting PCB Assembly

  • Clarify Requirements:

    • Determine the type of PCB (e.g., single-sided, double-sided, multilayer).
    • List all components to be assembled, along with their specifications and models.
    • Define the assembly quantity and production timeline.

  • Gather Market Information:

    • Research the price range for PCB assembly services in the market.
    • Understand different suppliers’ service quality, delivery timelines, and reputation.

  • Evaluate Costs:

    • Calculate the cost of raw materials, including the PCB board, components, and solder paste.
    • Estimate processing fees, covering steps such as surface mounting, soldering, testing, and assembly.
    • Consider additional costs like shipping and taxes.

  • Prepare the Quote:

    • Based on the cost evaluation, create a reasonable quote.
    • Ensure the quote includes all expenses, with each item’s specific cost clearly listed.
    • If necessary, offer multiple pricing options for different quantities or configurations for the client’s consideration.

  • Communication and Negotiation:

    • Discuss the quote details with the client, addressing any concerns or questions.
    • Adjust the quote based on client feedback to meet their needs.

Ordering PCB Assembly

Ordering PCB assembly involves several key steps to ensure that your PCB is correctly assembled and meets your specific requirements. Follow these steps when placing an order:

  1. Define Your Requirements:
    Before ordering, determine your needs, including the number of boards required, the types of components, delivery timeline, and any additional specific requests.

  2. Request a Quote:
    Once you’ve established your requirements, request a quote from your chosen service provider. As previously mentioned, the quote should detail the costs of labor, components, and any additional services required.

  3. Review the Quote:
    Examine the PCB assembly quote to ensure it aligns with your specifications and budget. If necessary, request changes or clarifications from the service provider.

  4. Place the Order:
    If satisfied with the quote, proceed with the order. Make sure to provide all necessary documents, such as your BOM, Gerber files, and any other required specifications.

  5. Payment:
    PCB assembly providers typically require upfront payment before starting the assembly process. Be sure you understand the payment terms and conditions and arrange payment accordingly.

  6. Quality Control:
    After assembly is complete, quality control is essential to ensure that the PCB meets your specifications. This includes checking for defects, verifying correct component placement, and conducting necessary tests.

  7. Delivery:
    Once quality control is completed, the service provider will ship the assembled PCBs to your preferred location.

Key Considerations

  • Quality Control: Focus on quality control throughout the quoting and ordering process. Ensure that the supplier has a robust quality management system and adequate testing capabilities to guarantee product quality.

  • Delivery Timeline: Plan the delivery schedule carefully to avoid project delays due to production setbacks. Stay in close communication with the supplier to keep track of production progress and address any potential issues promptly.

  • After-Sales Service: Choose a supplier that offers reliable after-sales service, ensuring you can receive support if issues arise during the product’s use.

Conclusion

Quoting and ordering PCB assembly is a multi-step process involving several factors. Quoting involves clarifying requirements, gathering market information, evaluating costs, preparing a quote, and negotiating with the supplier. Ordering involves selecting a supplier, providing necessary documents, confirming the order, making a deposit, tracking production progress, and final acceptance and payment. Throughout the process, it is crucial to pay attention to quality control, delivery timelines, and after-sales support to ensure success.