Suggestions complètes de conception d'assemblage de PCB d'un fabricant chinois de PCBA

Abstrait

This article presents a detailed methodology for pcb assembly design (PCBA), emphasizing the integration of manufacturing constraints into the electronic design process.

The guide navigates from fundamental concepts like schematic integrity and Bill of Materials (BOM) management to advanced layout considerations such as high-speed signal routing, power plane design, and thermal dissipation techniques. A significant portion is dedicated to the practical application of Design for Manufacturability (DFM) and Design for Assembly (DFA) principles, including panelization, fiducial placement, solder mask considerations, and component clearances.

It also covers the generation of a complete manufacturing data package, including Gerbers, BOM, and Centroid files. The objective is to equip design engineers with the knowledge to create robust PCBAs that meet performance specifications while being optimized for high-yield, low-cost automated assembly.

PCB Assembly design Guide

PCBs, or printed circuit boards, are the unsung heroes of modern electronics. Most users have no idea how the components in the electronic devices they know and love work together. But for engineers, OEMs, and designers, there is a lot to know and a lot to learn about PCBs. This PCB design guide was written to help both new and experienced engineers make smarter design decisions early on, resulting in the perfect components for their products. Let’s start with the basics:

1. What is a PCB?

Le circuit imprimé or PCB is the heart of any electronic device. It has two main functions: Housing electronic components, connecting components for operation The board itself is made of a non-conductive substrate, such as fiberglass, that is coated with copper on one or both sides. The copper conducts electricity and is etched away from the board, leaving the appropriate components to connect to each other through the circuit.

2. PCB Board PCBA. PCA. What is the correct name for a printed circuit board with all the components?

There are many acronyms used by industry experts for printed circuit boards. The most vexing question is, what is the difference between PCB and PCBA? Here is a breakdown of what they mean: PWB – Printed Wiring Board. The first term used when the connection of electronic components was simply point-to-point circuit work. PCB – Printed Circuit Board. Technically, the term PCB refers to the etched wiring board itself without any components mounted on it. Since printed circuit design often affects device functionality, the IPC Technical Executive Committee designated this term in 1999 as a term for new document development.

PCA – Printed Circuit Assembly. For clarity, it is used after the 1999 IPC change. PCBA – Printed Circuit Board Assembly. It is a printed circuit board with all the electronic components mounted on it. PCB is the most popular term when referring to the whole, assembled. When communicating with manufacturers and external suppliers, it is important to clarify what type of PCB is required – basic board or fully connected printed board assembly (PCBA). For an in-depth look at all the acronyms used for printed circuit boards, check out discussions by industry experts and more.

3. How do printed circuit boards work?

PCBAs are designed to provide a central hub for integrating all the electronic components in a device together. The board is created using multiple layers, with conductive paths or lines laminated to the substrate material. These copper traces are used to conduct electricity, acting as a circuit for all the components soldered to the board, thus powering the device, while providing insulation and safe current transfer.

4. What are PCBs made of?

Each PCB hardware component plays a vital role in powering an electronic device. PCB components include:

1. What are PCBs made of? The board itself consists of four key components: Substrate – The foundation of the PCB, the substrate is usually made of fiberglass or some other non-conductive material. The substrate can be single-layer or multi-layer. Copper – Used to carry electrical current, copper in PCBs replaces electrical wires.

Solder Mask – Metal used to create connections between the surface of a PCB and electronic components. The solder mask protects the electronic traces underneath from adverse conditions.

Silkscreen – Layer used to mark the connecting lines of electronic components, warnings, and other features unique to a device.

Before moving to final PCB production, prototypes must be verified to ensure that all components are connected and working properly to power the device.

6. What are the different types of PCBs?

To accommodate the design, application, and complexity of a device, several design decisions need to be made upfront. What type of PCB is needed first? Just like light guides, PCBs can be either rigid or flexible, depending on the design and application of the device.

Rigid PCBs – Designed to not bend or deviate from their original shape or position.

Flexible PCBs – Can be folded, twisted, and bent into the desired configuration. They are thinner, lighter, and can accommodate unique shapes.

Flexible PCB vs. Rigid Cost

From a cost perspective, here’s how the two compare:

Rigid PCBs

Typically a more cost-effective solution because they are easy to mass produce due to automation.

Flexible PCB Printed Circuit Boards Eliminate the need for additional connectors, which can reduce overall production costs. However, they require additional steps to secure components and automated assembly, which makes them cost-prohibitive. When choosing between rigid or flexible PCBs, cost is not the only determining factor – design constraints such as weight and space can also come into play. Layers of PCBs Single-layer PCBs Boards made from a single layer of substrate or base. Typically, one side of the substrate is coated with a thin layer of metal on one side of the base. Single-layer PCBs are ideal for rapid production due to their simple design and ease of automation.

Double-layer PCBs Boards that contain soldered electrical connections on both sides. This is achieved when copper or other conductive materials are applied to both sides of the board. For added flexibility, double-sided PCBs can utilize through-hole or surface mount (SMT) designs. Multi-layer PCBs When used for more complex designs, multi-layer boards include four or more layers. Other benefits of multi-layer PCBs are a smaller footprint and fewer wiring harnesses, which reduces overall weight. These PCBs are ideal for aerospace, handheld devices, battery and signal transmission, and many other applications.

7. What are the advantages of using a printed circuit board?

PCBs offer a number of benefits to engineers, OEMs, and designers of electronic devices, including: Minimal space requirements – Because all electronic connections are on the board, there is no need for multiple wires to carry current and take up valuable space on the device. Simplified installation and troubleshooting – All components are mounted on the PCB and clearly labeled for easy access during assembly and maintenance.

Simplified assembly – PCBs allow for quick assembly compared to other means (e.g., wired connections). Secure placement and connectivity – With PCBs, all electronic components are soldered to the board to ensure they stay in place. Manufacturing efficiency – When mass production is required, PCBs are more cost-effective than other connection methods. Reliable operation – The design of PCBs ensures stable operation because connections are made through copper wires that will not come loose.

8. What color is the circuit board?

It may seem like it’s the substrate that determines the color of the PCB, but it’s actually the solder mask. The substrate is usually green, but the solder mask over it can be blue, yellow, orange, purple, red, black, white, and of course, green.

9. Is the color of the PCB important?

There are many reasons to choose one, such as a specific color for the PCB substrate – whether it is branding, or if the system is pre-produced in one color and the boards produced are another color. In addition, some colors are easier to see contrast than with the naked eye, which can be an advantage when inspecting the board. However, if lighting is to be used, choosing a white surface for the PCB can help reflect light. In some cases, this additional control can provide more LED choices to optimize the design.

Depending on the application, sometimes it may be necessary to reflect light. In these applications, white PCBs are ideal. White PCBs are often used in LED light engines or LED lighting systems. On the other hand, there may be applications where light reflection is not desired, such as DJ equipment used in a dark nightclub. The color of the substrate is just one of the factors to consider during the schematic stage of PCB design.

1. What is the PCB design process like? There are eight processes involved in the manufacture of printed circuit boards, which can vary in complexity depending on the design of the device: PCB Design Basics (Simple List)
2. Concept of the Electronic Device
3. Electronic Schematic Creation
4. PCB Layout Design
5. Final Bill of Materials (BOM)
6. Prototype the PCB
7. Evaluate the Prototype
8. Install Firmware/Programming
9. Full Production The production process consists of the following steps:
10. Conception de circuits imprimés
11. Print the Copper of the Inner Layers
12. Remove Excess Copper
13. Inspection and Layer Alignment
14. Lamination of the Layers
15. Drilling
16. PCB Plating
17. RoHS Compliance

11. How Long Does It Take to Design and Produce a Custom PCB?

The turnaround time for custom PCBs depends on the vendor selected, as well as the complexity and volume of the project.

Our PCB capabilities start with design and end with final completion, and we are able to deliver turnaround services in as little as four weeks.

Dedicated warehouse space and advanced tools such as 3D printers enable our team to provide rapid prototyping and speed up the process.

6 Regularly Asked Concerns (Frequently Asked Questions) 

Résumé:

Le voyage d'un schéma électronique à un schéma totalement utile circuit imprimé La mise en place (PCBA) est pleine de défis possibles qui peuvent entraîner des modifications coûteuses et des retards de fabrication. Cet aperçu sert de feuille de route essentielle, reliant le vide important entre la conception numérique et la fabrication physique pour garantir le succès de votre projet dès le premier modèle.

En se concentrant sur des étapes pratiques et réalisables, cet article démystifie l'ensemble du processus de style PCBA. Nous allons au-delà de la théorie fondamentale des circuits pour couvrir les éléments essentiels qui garantissent que votre carte peut être construite efficacement et de manière fiable.

Sujets clés abordés dans ce guide:

• Fondations de PCBA Style : Apprenez à bien démarrer votre projet en développant un schéma propre et une nomenclature spécifique (Nomenclature). Nous couvrons les meilleures techniques pour la sélection des composants, en tenant compte de facteurs tels que la disponibilité, le coût et le type d'emballage pour l'assemblage automatisé.

• Stratégique Conception de circuits imprimés et Positionnement des composants: Découvrez comment positionner les composants pour des performances et une fabricabilité optimales. Cette section détaille les techniques de gestion de la dissipation thermique, garantissant l'intégrité du signal pour les circuits à haute vitesse et organisant votre format pour améliorer la procédure de configuration.

• Maîtriser le style pour la fabricabilité (DFM et DFA) : C'est le cœur de l'efficacité PCBA mise en page. Nous fournissons une liste détaillée pour Style pour la fabricabilité (DFM) et Mise en page pour la configuration (DFA), couvrant les réglementations essentielles pour les dégagements d'éléments, la mise en page des empreintes, les exigences de masque de soudure, les techniques de panneau et l'utilisation appropriée des marqueurs fiduciaires.

• Le dernier bundle d'informations de production: Évitez les erreurs de communication avec votre fournisseur. Cet aperçu explique précisément comment générer un bundle d'informations complet et précis, y compris Gerber documents de fabrication, une version mise à jour Nomenclature pour l'achat et un Centroïde (Choisir et placer) fichier pour l'assemblage automatisé.

En comprenant les idées contenues dans ce guide, vous serez équipé pour concevoir des PCBA robustes, abordables et hautes performances. Vous apprendrez à anticiper les obstacles à la production, à prévenir les problèmes de configuration courants et à optimiser le parcours de la mise en page à un produit fini.