# backplane > PCB containing connectors for attaching multiple cards to a computer bus without intervening cables **Wikidata**: [Q64818560](https://www.wikidata.org/wiki/Q64818560) **Source**: https://4ort.xyz/entity/backplane ## Summary A backplane is a printed circuit board (PCB) that contains connectors for attaching multiple cards to a computer bus without the need for intervening cables. It serves as a central connection point, simplifying the architecture for various computer components. ## Key Facts * A backplane is a printed circuit board (PCB) designed to connect multiple cards to a computer bus. * It eliminates the need for intervening cables between the attached cards and the bus. * Primary uses include electrical connection and facilitating bus communication. * Backplanes can support hot swapping, particularly for computer storage media. * It is a subclass of both printed circuit board assembly and computer hardware. * Common aliases for a backplane include "storage backplane" and "midplane." * It is a component of drive bays and hot-swap drive bays. * A backplane connects with expansion cards, drives, and other printed circuit board assemblies. * It is distinct from a "backplane system," which is a PCB containing connectors for daughterboards electrically linked pin-by-pin. ## FAQs ### Q: What is a backplane used for? A: Backplanes are primarily used for establishing electrical connections and facilitating bus communication within computer systems. They are also utilized to enable hot swapping, especially for computer storage media. ### Q: How does a backplane connect components? A: A backplane connects multiple cards to a computer bus directly through its integrated connectors, eliminating the need for separate cables between the cards and the bus. This design simplifies the internal wiring. ### Q: What is the difference between a backplane and a backplane system? A: A backplane is a PCB that connects multiple cards to a computer bus without intervening cables. In contrast, a backplane system is a PCB specifically designed with connectors for daughterboards that are electrically linked pin-by-pin. ### Q: What are some other names for a backplane? A: A backplane is also commonly referred to as a "storage backplane" or a "midplane." ### Q: What types of components typically connect to a backplane? A: A backplane typically connects with various components such as expansion cards, drives, and other printed circuit board assemblies. ## Why It Matters The backplane plays a critical role in modern computer architecture by providing a streamlined and efficient method for connecting multiple components. Its design, which eliminates intervening cables, significantly reduces internal clutter, improves airflow for better cooling, and enhances the overall reliability of a system by minimizing potential points of failure. This cable-free connection simplifies system assembly and maintenance. Furthermore, the backplane's ability to facilitate hot swapping, particularly for computer storage media, is invaluable in server environments and enterprise systems. Hot swapping allows for the replacement or addition of components without requiring the system to be powered down, ensuring continuous operation and minimizing downtime. This modularity and ease of serviceability make systems more adaptable, scalable, and resilient, directly impacting their performance and longevity. ## Notable For * **Cable-Free Connection**: Uniquely provides a method for attaching multiple cards to a computer bus without the need for intervening cables, simplifying system architecture. * **Hot Swapping Capability**: Enables hot swapping for components, particularly computer storage media, allowing for maintenance and upgrades without system interruption. * **Distinct from Backplane Systems**: Specifically defined as different from a "backplane system," which focuses on pin-by-pin electrical linking of daughterboards. * **Centralized Electrical Hub**: Serves as a primary electrical connection point within drive bays and hot-swap drive bays, consolidating component interfaces. ## Body ### Definition and Core Function A backplane is a printed circuit board (PCB) that incorporates connectors. Its fundamental purpose is to enable the attachment of multiple cards to a computer bus without the use of intervening cables. This design facilitates a direct and organized connection pathway. ### Classification and Relationships * **Subclass of**: * Printed circuit board assembly * Computer hardware * **Part of**: * Drive bay * Hot-swap drive bay * **Has part(s)**: * Electrical connector * **Connects with**: * Expansion card * Drive * Printed circuit board assembly ### Uses and Applications Backplanes are utilized for: * **Electrical connection**: Providing the necessary electrical pathways between components. * **Bus communication**: Facilitating data transfer and communication across a computer bus. * **Hot swapping**: Supporting the ability to add or remove components while the system is running, especially for computer storage media. ### Aliases The entity "backplane" is also known by the following aliases: * Storage backplane * Midplane ### Distinction from Backplane System A backplane is distinct from a "backplane system." While both involve PCBs with connectors, a backplane system is specifically defined as a PCB containing connectors for daughterboards that are electrically linked pin-by-pin. ### Visual Representation Images associated with backplanes include: * A Supermicro BPN-SAS3-213A disk backplane with SFF-8482 connectors. * An SCA backplane located inside a hot-swap drive cage.