The PCB Design, Assembly, and Trends Blog
  • Solutions
    • PCB Designers
    • IC Vendors
    • CAD Vendors
  • Products
    • Desktop
    • Ultra BOM
    • Free Reader
    • Online Reader
  • Resources
    • Blog
    • Video Library
    • Library Standards
  • Contact
Login
Sign Up
The PCB Design, Assembly, and Trends Blog

LGA Package Footprints and the Difficulty in Finding Full Package Models

May 6, 2020
in Component Parameters & Applications, PCB Footprints
4 min read
Share160TweetPin
LGA package footprints on a CPU
If you want to put this CPU into your next design, you need to find LGA package footprints for this component.

 

Most HDI (high density interconnect) designers and many high speed designers are familiar with BGA (ball grid array) components, which provide a way to connect dense, high pin-count components to a PCB. These components function as a standard flip-chip BGA, but without solder balls for surface-mounting. LGA (land grid array) packages are designed to fit either into a specific LGA socket, or they can be soldered using standard SMD assembly techniques.

On the design side, you need access to accurate LGA package footprints when placing these components in a PCB layout. What information needs to be included in an LGA, and what is the difference between the socket and the actual component package? When you need to find LGA package footprints for your components, an electronics search engine can help you find the footprints you need for your LGA, as well as for any other components you need.

BGA vs. LGA Package Footprints

Since most designers are familiar with BGA footprints and mounting, they deserve a comparison with LGA components. A BGA component includes solder balls on the bottom of the component, and the solder balls mount directly to pads on the PCB. The designer needs to use an escape routing on the surface layer or through interior layers to reach the BGA pads. This mounting style is popular for many high pin-count components, such as FPGAs or baseband chips in mobile products.

An LGA attaches to a socket, and the socket attaches directly to the board using through-hole mounting or SMD mounting. The LGA socket or the component itself may contain some smaller passives to support the component functions. This means, when designing a PCB with an LGA, LGA package footprints need to include pad or hole locations, which define where traces will be routed to send signals to components. The actual IC then mounts to the LGA socket and snaps in place with a mounting bracket. This is the standard method for placing CPUs in new computers.

BGA vs LGA comparison
LGA socket and BGA package comparison. The LGA socket on the left contains pads where an IC is attached, while the BGA contains solder balls that attach directly to pads on the PCB.

 

If you look at BGA and LGA package footprints, they look very similar, but there are some key differences. Both types of components contain arrangements of pads to match the pitch and layouts required on the PCB. For a BGA, the only other required information is a courtyard outline and possibly a silkscreen outline. Note that you should include an indicator in your PCB footprint for pin 1 on the component.

For an LGA, the component is more complicated and contains some mechanical mounting brackets. The LGA also contains an arrangement of pads or holes for mounting, but it also contains some mechanical brackets to attach the LGA component to the socket. These mechanicals need to be defined in the PCB footprint on a mechanical layer. This is quite important for ensuring you maintain minimum clearances from nearby components.

What to Include in Your LGA Footprint

The pad arrangement for each type of component can be easily created from a datasheet, but a 3D model for an LGA is more complicated than for a BGA. An IC with BGA mounting will only need, at minimum, a simple black box to represent the component. In contrast, a 3D model for an LGA requires the socket, backplate, and top bracket to fully represent the component. 

If you’re not a mechanical designer, you can define the outer limits for LGA footprint packages by extending the component courtyard to match the socket and bracket outline. You can also design simple mechanicals for the socket and bracket that match the outer edges of the component, which will define a simple outline for the LGA socket and bracket. Be sure to check your datasheets when creating your own component footprints and models.

LGA package footprints
AutoCAD model (DXF file) for a 2040540-1 LGA socket (TE Connectivity).

 

A better way to find all the component data you need, including LGA footprint packages, is to use an electronic parts search engine service. You can save yourself time when creating footprints for your components and you’ll know your footprints and 3D models will be correct. DXF, STP, and IGS files can be easily found with the right service and these models can be used to define the mechanical portion of your LGA package footprints.

Use a Search Engine for LGA Footprints

Instead of staring at a datasheet and drawing outlines in a CAD application, you should try using a comprehensive parts search engine to find your component data. You’ll be able to quickly find schematic symbols, PCB footprints, 3D models, specifications, and sourcing information for your components. This helps you qualify new components before you start a new design, and you can quickly bring component data directly into your ECAD software.

This lets you see component specs directly in your search results, and you can quickly narrow down to some candidate components before you start combing through datasheets. You can also take advantage of integrated search features in your CAD applications to quickly fund verified models and datasheets for your components.

Next time you need LGA package footprints for a new design, try finding the components you need from a parts search service like Ultra Librarian. You’ll have access to a range of 2D and 3D LGA package models from major manufacturers, and you’ll see real-time sourcing information from worldwide distributors. You can then import your data into popular ECAD applications and use your new components in your designs.

Footprint and 3D electronic component model creation takes dedicated resources and time, but Ultra Librarian helps streamline these processes. Working with Ultra Librarian will set up your team for success and ensure your finished product matches your design. Register today for free!

The Ultra Librarian Team

Ultra Librarian offers the world's largest PCB CAD library, putting cutting-edge materials at your fingertips so you can build better products faster—all for free.

Related Posts

Dual full-bridge MOSFET driver
Component Parameters & Applications

Selecting a Highly Efficient, Dual Full-Bridge MOSFET Driver

Motor control solutions can be intimidating for new designers, but they have surprisingly simple topology and driving mechanisms.

March 4, 2021
CAN bus transceiver signals
Component Parameters & Applications

TJA1050 vs. MCP2551: Surface Mount, High-Speed CAN Transceivers

CAN bus transceiver signal lines If you design and develop electronics systems, you likely encounter buzzwords such as IoT, Industrial...

March 2, 2021

If you're looking for any of our component footprints or models, we have readily available and free options for you and your design team. Search our library for the solution you've been looking for.

Search our Library

Free Design Resources

Ultra Librarian is the worlds largest online – and always free – PCB CAD library. Build products better, faster, and more accurately with easy access to vendor-verified symbols, footprints, and 3D models. Register today to start searching the right components for your next design.

Register Today

Recommended

Creating a custom schematic symbol in a SPICE program.

Component Footprints for Hardware Start-Ups

August 18, 2020
Reference Design Cloud with TINAMIC and Ultra Librarian for Motion Control Components

EMA Launches Ultra Librarian Reference Design Cloud Starting with TRINAMIC Motion Control Components

November 13, 2018
Trinamic Reference Design PR

Interactive Reference Designs are Now Available From Trinamic in Cadence Systems Formats on Ultra Librarian

February 23, 2021
Variants of the 74HC595 in the Ultra Librarian search engine.

74HC4051: Analog Switch for Multiplexer-Demultiplexer

October 22, 2020

Search Our Blog

No Result
View All Result

Categories

  • Announcement
  • Component Parameters & Applications
  • ECAD/MCAD Workflow & Team Management
  • Partner Content
  • PCB Design & Layouts
  • PCB Footprints
  • STEP Models & 3D Integrations
  • Uncategorized
Next Post
LGA Package Footprints and the Difficulty in Finding Full Package Models

How to Use an E Parts Finder to Speed Up Your Component Selection

LGA Package Footprints and the Difficulty in Finding Full Package Models

SMD Component Datasheets: Mastering Enclosure Constraints and Connectivity

Ultra Librarian

  • Legal
  • Standards
  • FAQ
  • Blog
  • Advertise
  • Submit Feed

CAD Tools

  • Altium
  • Cadence
  • Eagle
  • KiCad
  • OrCAD Cloud
  • PADS
  • Pulsonix
  • Quadcept

IC Partners

  • Analog Devices
  • Browse by Manufacturer
  • Digi-Key
  • TE Connectivity
  • Texas Instruments
  • Toshiba

  

© Copyright Ultra Librarian 2020

No Result
View All Result
  • Solutions
    • PCB Designers
    • IC Vendors
    • CAD Vendors
  • Products
    • Desktop
    • Ultra BOM
    • Free Reader
    • Online Reader
  • Resources
    • Blog
    • Video Library
    • Library Standards
  • Contact