Skip to main content

An Introduction to Electronic Component Naming Conventions

Published Date
Author Cadence PCB Solutions

Key Takeaways

  • Electronic component naming conventions are used to describe the semiconductor devices, passive components, and connectors used in a circuit design.

  • In electronic component naming conventions, the component family is of great importance for naming through-hole as well as surface mount land patterns.

  • The lead spacing or hole-to-hole location where component leads are inserted forms the first number in the naming convention for standard through-hole components.

PCB

PCBs are hardware realizations of circuits designed by engineers. Circuit blueprints are physically constructed using electronic components such as resistors, capacitors, inductors, diodes, and integrated circuits. When all the electronic components function as intended, the required output can be obtained from the circuit board.

In the PCB design schematic stage, electrical connections between the various electronic components in a circuit are established. The schematic follows a certain electronic component naming convention for easy understanding and identification. In this article, we will discuss the electronic components used in a PCB and their naming conventions.

Common Electronic Components

Electronic components are essential for fabricating a PCB; when electronic components are connected as per a circuit diagram, they form a meaningful PCB. If any electronic component fails to perform its role, the board may fail to achieve the target function or output.

In PCBs, electronic components belonging to the same class may vary in their type, dimension, geometry, package, or electrical specification. Here are some common electronic components in PCBs:

Resistors - The most common electronic component in a PCB. They are used to limit the current flow in a path. There are different types of resistors available, including carbon film resistors, metal film resistors, and chip resistors.

Capacitors - The second most common electronic component in a PCB. Capacitors can be polarized or non-polarized. Some commonly used capacitor types are mica capacitors, tantalum capacitors, and ceramic capacitors.

Inductors - Inductors are used to store electrical energy in the form of magnetic energy. The simplest inductor can be obtained by wounding a wire into a coil.

Diodes - Diodes are semiconductor electronic components employed for allowing current flow in one direction while blocking reverse current flow. They are also used for voltage regulation and lightning purposes. Commonly used diodes include signal diodes, power diodes, Zener diodes, and light-emitting diodes.

Transistors - Transistors are three-terminal devices used either as semiconductor switches or as linear amplifiers.

Integrated circuits - Most circuit boards require bridge rectifiers, oscillators, amplifiers, and timers. These circuits are available in the form of integrated circuits.

Transformers - Employed in circuit boards for galvanic isolation, voltage boosting, or voltage reduction.

The list of electronic components used in PCBs is endless—this list is by no means exhaustive. In a PCB schematic, each component is given a unique name for easy identification, which helps readers understand the circuit component type, dimension, and geometry. We will explore these unique names next.

Electronic Component Naming Conventions

Electronic component naming conventions are used to describe the semiconductor devices, passive components, and connectors used in circuit design. Electronic component naming conventions assign a unique name to the PCB footprints that the electronic components are being soldered to. PCB footprint naming conventions for through-hole components and surface mount components are different. The IPC standards IPC 7251 and IPC 7351 give the reference standards for naming through-hole and surface mount components, respectively.

In electronic component naming conventions, the component family is of great importance both in naming the through-hole as well as surface mount land patterns. In the naming convention of standard through-hole components, the component family covers 3-6 characters of the PCB through-hole footprint name, as per IPC 7251B. The lead spacing or hole-to-hole location where the component leads are inserted forms the first number in the naming convention. The component dimensions are significant in describing the names for the pad arrangement in the PCB.

All component dimensions are presented in millimeters, with two places shifted to the right of the decimal places and without any leading zeros. The numbers that follow the lead spacing correspond to component dimensions. Several other characters are included as component body identifiers to increase the uniqueness of the naming. Some of the common component body identifiers used in electronic component naming conventions are given below, in their priority order.

P = Pitch for components with more than two leads

W = Component lead diameter (or maximum lead width)

L = Body length for horizontal mounting

D = Body diameter for round component body

T = Body thickness for rectangular component body

H = Height for vertically mounted components

Q = Pin quantity for components with more than two leads

R = Number of rows for connectors

A, B & C = The fabrication complexity level as defined in the IPC-2221 and IPC-2222

Decoding Electronic Component Naming

Let’s decode the naming convention of a standard through-hole resistor. RESAD800W52L600D150B describes resistor (RES) of axial diameter (AD), horizontal mounting type (AD) of lead spacing 8.00, lead width 0.52, body length 6.00, and body diameter 1.50. The standard naming convention followed is:

RESAD + Lead Spacing + W Lead Width + L Body Length + D Body Diameter

Circuit designers follow the electronic component naming conventions described by IPC standards in their schematics to ensure easy comprehension of their designs. Cadence’s PCB design and analysis software can aid in this process.

Leading electronics providers rely on Cadence products to optimize power, space, and energy needs for a wide variety of market applications. If you’re looking to learn more about our innovative solutions, talk to our team of experts or subscribe to our YouTube channel.