Free Trials

Download a free trial to find out which Altium software best suits your needs

How to Buy

Contact your local sales office to get started on improving your design environment


Download the latest in PCB design and EDA software

  • Altium Designer

    Complete Environment for Schematic + Layout

  • CircuitStudio

    Entry Level, Professional PCB Design Tool

  • CircuitMaker

    Community Based PCB Design Tool


    Agile PCB Design For Teams

  • Altium 365

    Connecting PCB Design to the Manufacturing Floor

  • Altium Concord Pro

    Complete Solution for Library Management

  • Octopart

    Extensive, Easy-to-Use Component Database

  • PDN Analyzer

    Natural and Effortless Power Distribution Network Analysis

  • See All Extensions

    World-Renowned Technology for Embedded Systems Development

  • Live Courses

    Learn best practices with instructional training available worldwide

  • On-Demand Courses

    Gain comprehensive knowledge without leaving your home or office

  • Altium 365 Viewer

    View & Share electronic designs in your browser

  • Altium Designer 20

    The most powerful, modern and easy-to-use PCB design tool for professional use


    Annual PCB Design Summit

    • Forum

      Where Altium users and enthusiasts can interact with each other

    • Blog

      Our blog about things that interest us and hopefully you too

    • Ideas

      Submit ideas and vote for new features you want in Altium tools

    • Bug Crunch

      Help make the software better by submitting bugs and voting on what's important

    • Wall

      A stream of events on AltiumLive you follow by participating in or subscribing to

    • Beta Program

      Information about participating in our Beta program and getting early access to Altium tools

    All Resources

    Explore the latest content from blog posts to social media and technical white papers gathered together for your convenience


    Take a look at what download options are available to best suit your needs

    How to Buy

    Contact your local sales office to get started improving your design environment

    • Documentation

      The documentation area is where you can find extensive, versioned information about our software online, for free.

    • Training & Events

      View the schedule and register for training events all around the world and online

    • Design Content

      Browse our vast library of free design content including components, templates and reference designs

    • Webinars

      Attend a live webinar online or get instant access to our on demand series of webinars

    • Support

      Get your questions answered with our variety of direct support and self-service options

    • Technical Papers

      Stay up to date with the latest technology and industry trends with our complete collection of technical white papers.

    • Video Library

      Quick and to-the-point video tutorials to get you started with Altium Designer

    Understanding Solder Bridge Shorts: Bake Your Cookie and Eat It Too

    December 8, 2017

    Cookies on a baking sheet

    I love the idea of baking. Especially around the holidays, there’s something thrilling and therapeutic in planning to bake up elaborate platters of cookies and bring them to parties. In reality, what I like is to eat cookie dough. The actual rolling or spooning out cookies onto a pan and waiting for them to bake is an exercise in both tedium and restraint. When I lose my patience, I try to cram as many cookies onto the tray as possible; of course, this results in a single, giant cookie that, begrudgingly, I have to eat all myself.

    Whether you’re wallowing in the winter planning of too-many holiday cookies, or just wishing for a more convenient way to plan out your space-constraints, the goal is always going to be designing the layout of your baking sheet to avoid scrapping that whole tray of cookies. If you spent the time making them, you should earn the reward of eating them. That lesson ought to be true for a lot of things though, shouldn’t it?

    Unfortunately, if I overcrowd my PCB it doesn’t just turn into a cookie. No, being impatient and not working within space constraints can be much more costly than ruining a batch of cookies. Size and complexity of design are major factors that affect PCB manufacturing costs; however, more than that, overcrowded designs can lead to malfunctions and PCB shorts. Being able to manage your design to effectively work within space constraints will save (and probably earn) you more money and time that could be better spent on other things (like, for example, eating more holiday cookies).

    Electrical shorts

    The most common issue with high-density designs is frequent electrical shorts. An unfortunate reality (an inconvenient truth?) is that oftentimes electrical shorts can occur despite how well you designed your PCB. Solder bridges are likely so long as you have a high-density design; however, high-density designs are often unavoidable with the increasing demands from PCBs.

    When you decrease the size of pads and the distance between them, there is more solder paste in a smaller volume. That paste is more likely to spill out of the appropriate stencil defined areas and create solder bridges to neighboring pads. Like accidentally baking a giant cookie, the only way to avoid those bridges is by having buffer space between the pads that is enough to protect them from a little bit of spillover from their neighbors. It isn’t designing for failure, but rather allocating design resources into understanding shortage risk and managing it appropriately.

    Guy watching smoke come out of the oven.
    Overheating your PCB and components is just as bad a burning cookies, and more expensive to redo.


    Other manufacturing stages can also be more difficult with higher density PCB designs. Stencil issues compound the risk of solder bridging, especially in tight arrays of small components. When there is high component density, you have the highest risk of solder paste smearing or misalignment which results in inadequate buffer space. Having buffer space enables your PCB design to prevent solder paste bridges from forming. Without that buffer space, solder bridges become more likely and encourage the occurrence of errors like shorting.

    Pick and place machine accuracy also limits the density you can use in your PCB design. If the accuracy of the machine is very high, you’ll have more flexibility to pack in your components. However, also consider the tooling used on the pick and place. Placement tools can extend beyond the edge of the component, which can add difficulty to tightly-packed or small component placing.

    Depending on the place I’m living, sometimes I need a stepstool to reach whatever I’ve stored in the top cupboards. This might impede my cookie-baking speed, but it won’t ultimately keep me from baking. Component height also becomes an issue if the pick and place can’t reach the location next to a taller component like in the case of resistors next to headers. Imagine if you were decorating a cookie and put giant marshmallows down, then needed to draw in delicate icing without moving the cookie. I usually eat the cookie before the decorating process, but I can’t just eat a PCB.

    Marshmallow snowman cookie
    Variable height components make cookies as tricky as a PCB

    Inspection, rework, and repair

    After manufacturing, the challenges of a high-density design aren’t over. Inspection is more challenging because edges of components aren’t easily visible when they are close together like they are in high-density designs. You may be blinded from viewing solder joints and verifying standoff heights. If you have varying heights, then the components might actively block each other from view.

    Finding the issues in a high-density design isn’t the entire problem either—when you have components so close together, you can encounter other processes that will slow down or can even cause errors of their own. You might have to remove other components to get at whichever component you need to fix, and even with the tiniest tweezer and most stable hands, reheating sections of the board will assuredly remelt the solder and cause slippage. You may also need to add a heat shield for nearby components since there’s less total room for heat to dissipate.

    Operational requirements on spacing

    Before any scenarios in which errors, bridges, or shorts occur exist, the foremost demand on component spacing is from operational requirements. There are formalized specifications for spacing: the most commonly cited is IPC-D-279, section 3.3.9, but there are also manufacturer recommendations, like this chart from OCM, often for a specific packaging, or application. Once you have varied component and packaging types, the specifications often aren’t extensive enough to provide the necessary guidelines.

    The requirements for component spacing depend on the function of the board, the operating parameters, and its environment. Consider isolation requirements (based on voltage, RFI, or EMC) before you try and reduce spacing, or you’ll be shortening the life of the entire product, and possibly introducing safety issues, to save a little bit of upfront cost. You might also encounter handling and safety requirements that will determine edge spacing. Initially, that buffer seems like an easy place to cut excess, but cutting your buffer could have catastrophic impacts on the lifespan on the board.

    Spoon and bowl with spilled icing
    Spilled icing is delicious. Spilled solder paste is disastrous.

    On top of all the other information that you need to keep track of while designing, component spacing and being aware of solder bridge shorts may seem like a troubling task. Trust me, coming from someone who often forgets to preheat the oven before putting anything into it, I understand the difficulty of keeping track of multiple instructions. But when you are doing high-density design, use Altium Designer with its robust design rules checking, can make sure “keep out,” areas and other physical restrictions for components are all accounted for, and that can import manufacturer rules to check for compatibility before designing.

    All this and other great design tools can be at your fingertips to make your design life more manageable. Learn more about solder bridge shorts and component spacing by talking to an Altium Expert today.

    Check out Altium in action...

    Powerful PCB Design

    most recent articles

    Back to Home