Coordinate files are standard files used by processing equipment programs to locate the coordinates of PCBA mounted components. Automated equipment used for PCBA processing, such as surface mount machines, SPI, first piece inspection machines, AOI, etc., almost all require positioning point coordinates. Coordinate files are mainly used to locate the coordinates of components, and engineers need to use this file when making programs.

Coordinate files can also be exported from PCB files. The following image is a standard coordinate file, also known as Pick&Place files, which are mostly in txt format.

After all the processes of PCBA processing are completed, customers generally have various testing project requirements, including testing project parameters, technical indicators, etc. In addition, customers usually provide testing guidance documents that include guidance and technical requirements for the professional parameters required for testing.

The following is a functional test file for a certain power circuit board. When designing and manufacturing a test stand, the product must pass all tests according to the test document to be considered functionally qualified.

When matching the above files with PCB processing requirements, we focus on the BOM file.

BOM is an essential reference document for material procurement and product production, including information such as material model, brand, description, packaging, part number, quantity, circuit board version, auxiliary consumables, specific component specifications, and production instructions. Its accuracy directly affects product quality.

A complete and detailed BOM can make quotations fast and accurate, ensuring fewer errors in component procurement and production processes, and greatly improving product delivery rates. The following are the main steps for checking and analyzing BOM.

The engineer first confirms whether the component models are complete and whether the packaging brand description is consistent (this information can be verified by checking the specification sheet). Engineers also need to confirm whether the corresponding models and tag numbers are compatible, mainly for components such as capacitors, resistors, diodes, and transistors. As the number of these components increases, they are easily overlooked by engineers, resulting in mismatched quantities and causing difficulties in actual procurement work.

For example, the screenshot below shows that the actual tag number is 26, but only 25 is displayed on the BOM table. In this case, we usually need to inform the customer to operate according to the original tag number table.

At the same time, engineers must confirm that the tag number is not duplicated and that it does indeed exist on the circuit board. Therefore, all of these situations should be separately verified during the first article inspection.

There are also some aspects that are easily overlooked, such as the specific models of some resistors that are not included in the BOM, only parameter descriptions. Inconsistent content descriptions can easily lead to PCB manufacturers buying the wrong materials or causing interference to the production line. The following figure shows the situation of inconsistent capacitor value descriptions.

The most significant impact on production among inconsistent information is the conflicting information regarding material packaging and circuit board layout.

In order to prevent such problems from occurring in the actual production process, it is usually necessary for warehouse personnel to verify that the parameters of necessary passive components are consistent with the BOM. In the final incoming inspection stage, the circuit board and materials need to be obtained and placed on a blank circuit board to check for packaging size issues.

Assuming that the material size is found to be inconsistent with the bare board, it is necessary to promptly propose and communicate a solution with the customer. If the customer needs to replace the board, replace it, and if the customer needs to find alternative materials, update the material. For example, in the following picture, the size of the cement resistor is too large and the spacing between the circuit boards is too small, resulting in unreasonable installation.

At the same time, there are also many hidden problems, namely, the size of the material pins is not consistent with the size of the circuit board aperture, which leads to the inability to insert components into the PCB board. All these details must be eliminated one by one before the factory starts up. If these problems are not eliminated before production, it will lead to the shutdown of the production line, seriously affecting efficiency and progress.

To check whether the parameters of the actual incoming materials and passive components are consistent, it is necessary to use multimeters, bridges, oscilloscopes, etc. to measure passive components such as resistors, capacitors, and inductors. Common problems include mismatched resistance values and insufficient capacitor withstand voltage. The main reason for these problems is that the component supplier did not classify and control the incoming materials properly.

Handle specific annotations in BOM, such as component program burning, specific component installation, etc.

For example, in the screenshot below, the BOM clearly states that the single-sided machine DD2 needs to download the file first, so we need to download the program file first before proceeding with the next testing process.

As shown below, the installation requirements for D1 LED specify the installation height of the LED and require it to be flush with the edge of the circuit board.

Confirm auxiliary materials and consumables, such as three proof paint, adhesive red glue, welding connection lines, labels, additional materials and consumables required for production assembly, etc.

After checking the BOM list, entering the material procurement stage, it is usually necessary to first confirm the market inventory of active components, especially the new main ICs, MCUs, etc. of large brands. Due to the irreplaceability of active components, long delivery cycles from component factories, and high value of individual products, material procurement plays a crucial role in overall project delivery and cost control.

Problem 1: Shortage in the component market and long delivery cycles for component factories

Suggestion: It is normal for the new material to be out of stock within three years, but it can be tried within five years. If the original packaging is unopened and the storage environment is good, it can be used within five years. However, it is recommended to first make a sample to see if the tin plating is good, and ensure that the sample is OK before mass production.

Suggestion: Compared to outdated products, component factories update their materials, and new components can replace outdated products in terms of functionality, with lower power consumption and stronger performance. In addition to reading the specification sheet, we can also browse some website information, such as DIGIKEY, MOUSER, and other official websites that have many updated material tips for corresponding products.

Suggestion: When encountering this problem in the procurement of active and passive components, they need to be handled separately. If encountering this problem in the procurement of active components, customers generally need to cooperate with PCBA manufacturers to provide alternative components or modify or adjust solutions.

If we encounter this problem when purchasing passive components, we can provide multiple well-known brands of passive components with the same parameters as substitutes, such as resistors, capacitors, inductors, etc. As for connectors, many of our domestic connectors can also meet the needs of customers' products, reduce procurement costs, accelerate delivery time, and stabilize product availability.

Meanwhile, in the process of continuous communication with customers, we can provide suggestions based on their future order needs and prepare some components in advance to cope with market fluctuations and material shortages.

Finally, as an engineer handling BOM and purchasing components, it is essential to have a basic knowledge of electronic components, be patient, understand the local component market situation, be proactive when purchasing components, adopt different negotiation strategies for components with different unit prices and quantities, and continuously accumulate high-quality supply channels.

If pursuing cost-effective FPC manufacturing services, choosing a Chinese manufacturer is the best choice. As a manufacturing powerhouse, China has abundant resources, cheap labor, and a large number of technical personnel. We recommend Haibo, a Chinese FPC assembly service provider with over 10 years of experience, who has performed outstandingly in various aspects

Efficient and reasonable quotation:There is an efficient quotation process to assist you in making decisions, providing reasonable prices and highly competitive quotes in China.
High quality and reliable products:Produce high standard printed circuit boards, manufacture and test according to specifications, international standards, and internal controls, and conduct pre production inspections to ensure robust processes.
Quick and on-time delivery:The assembly equipment is in good condition, with high productivity, minimal downtime, short delivery time, and also provides urgent services.
Timely and effective response:Always respond to customer needs, provide accurate information, answer questions through multiple channels, and offer one-stop services.
Strong technical strength:China's FPC manufacturing technology is leading, and Haibo has a complete SMT solution that covers assembly, inspection, and other capabilities. It also provides prototype production and customization services.