- smt007 Magazine
Latest IssuesCurrent Issue
Boost Your Sales
Every part of your business can be evaluated as a process, including your sales funnel. Optimizing your selling process requires a coordinated effort between marketing and sales. In this issue, industry experts in marketing and sales offer their best advice on how to boost your sales efforts.
- Events||| MENU
- smt007 Magazine
How to Streamline PCB Thermal DesignApril 1, 2015 | John Parry, Mentor Graphics Corporation
Estimated reading time: 2 minutes
Thermal issues with a PCB design are mostly determined during the component selection and layout phases. After this point, only remedial actions are possible if components are found to run too hot. Addressing thermal issues early in PCB design, starting at the system or enclosure level to understand the flow environment critical for air-cooled electronics, can streamline the process. Assumptions about the airflow uniformity in early design that subsequently prove unachievable can have a disastrous effect on the commercial viability of the product and meeting the market window.
Begin Before Placement and Layout
Substantial work can be done well before layout is completed within the electrical design flow. A simple representation of the enclosure can provide information about the air flow profile over the board. Start by smearing the total board power over the total board surface, which will provide a temperature map that will show any hot regions that are caused by a badly distributed air flow. Treat the board as a block with an isotropic conductivity of between 5 W/mK and 10 W/mK to optimize enclosure-level air flow ahead of the PCB design.
Components inject heat locally into the board so the heat flux density into the board below a component will be higher than the average for the board. As a result, the local board temperature will be higher than that predicted in the simulation. Refine the model before using the board temperature to estimate component temperatures. If the board temperature at any point is close to the maximum component case temperature, this limit will be exceeded once the component heat sources are represented discretely.
Guesstimate Component Power
At this stage, make a best-guess estimate of the individual power budgets for the main heat dissipating components that will be used in the design and the approximate size of those packages. This will enable describing them as footprint heat sources in the simulation, smearing the remainder of heat uniformly over the board surface.
Before Selecting the Package, Use 3D Component Models
Include some form of 3D component model in the simulation before the component selection is finalized. By feeding the thermal results back before this milestone is reached, the thermal performance will more likely be considered in the package selection criteria. Some ICs are available in more than one package style, and not all package styles perform equally well from a thermal point of view. The need for a heatsink later may be eliminated by appropriate package selection.
Component temperature, either in the form of a case temperature or junction temperature depending on how the manufacturer has specified the component, is the key measure used to indicate whether the design is thermally acceptable.
Editor's Note: This article originally appeared in the March issue of SMT Magazine.
Siemens Joins Semiconductor Education Alliance to Address Skills and Talent Shortage in Global Semiconductor Industry02/29/2024 | Siemens Digital Industries
Siemens Digital Industries Software announced today it has joined the Semiconductor Education Alliance to help build and nurture thriving communities of practice across the integrated circuit (IC) design and Electronic Design Automation (EDA) industries, from teachers and schools to universities, publishers, educational technology companies and research organizations.
At DesignCon, the I-Connect007 Editorial Team met with Brad Griffin, product marketing group director for the System Analysis Group at Cadence Design Systems. Brad explains how this analysis tool enables designers to address SI and PI issues early in the design process, before they become costly errors, and why he believes his late co-worker Dennis Nagel would be proud to see his efforts come to fruition.
Sondrel, a leading provider of ultra-complex chips for leading global technology brands, announces that it has secured two new contracts to supply Design Consultancy Services for a Network processor chip and a Radio Transceiver chip.
With the seemingly endless ways that electronic products are worming their way into our lives, what was once “nice to own” is increasingly considered indispensable. The capabilities of these products have been driven by relentless improvements at every level of the manufacturing chain, from individual transistors (which are approaching Angstrom levels) to systems the size of buildings supporting Bitcoin mining and increasingly distributed AI products.
Indium Corporation to Showcase Proven EV Products and High-Reliability Alloys at Productronica China02/28/2024 | Indium Corporation
As a materials pioneer and trusted partner in electric vehicle (EV) and e-Mobility manufacturing, Indium Corporation is proud to showcase its high-reliability alloys and soldering solutions at Productronica China, March 20-22, in Shanghai.