heatsinks.wordpress.com is moving to a new home!

March 7, 2011

We want to thank all our readers for visiting our blog and making it a huge success!   All of us at Advanced Thermal Solutions have worked hard to provide accurate and relevant information on thermal management.  It’s what we do 24×7 and we are delighted to share what we know with others.  And now we’ll be expanding our blog!

In about a week we’ll be moving to our new home on qats.com We’ll post our new site URL here when we finish our set up.

Until then, we hope you benefit from the many excellent articles posted here at heatsinks.wordpress.com

Heat Sink Selection Made Easy Webinar Available Now in our Archives

February 28, 2011

ATS’s recent webinar, “Heat Sink Selection Made Easy” is now available in the ATS Webinar Archive.   Our webinar covered important topics such as:

  • A comparison of heat sink characterization methods
  • Why heat management is a challenge?
  • What are the various heat sink types and how are they manufactured?
  • A case study showing what information you really need in order to choose the correct heat sink for your application.

Taught by Dr. Kaveh Azar, the 60 minute archived webinar is no charge to our viewers.
You can view our webinar at this link: “Heat Sink Selection Made Easy Archive

What if you don’t have time to even view the webinar, your project timeline is so short?  No worries, ATS can help, just click over to our Heat Sink Design Services to learn how our team can help your team manage even the toughest thermal challenge

Interview with David Copeland, Keynote Speaker for “The Heat is On” MEPTEC Thermal Symposium

February 23, 2011

ATS’s Qpedia Thermal eMagazine is pleased to be a Media Sponsor of the Electronics Thermal Week, co-sponsored by MEPTEC and SEMI-THERM.  As part of that series, we are developing some posts around the speakers, issues and suppliers involved.   This is our kick off article, an interview with David Copeland, the Keynote Speaker for “The Heat is On” MEPTEC Conference being held during Thermal Week.

David Copeland is a Thermal Engineer working in the Packaging Technology department of Oracle’s Microelectronics Group, developing packaging and cooling technology for UltraSPARC processors and the systems which use them. Areas of development include thermal interfaces, heat spreading materials, single-phase and phase-change liquid cooling, and data center cooling. He received his BS from Massachusetts Institute of Technology, MS from Stanford University and DrEng from Tokyo Institute of Technology, all in Mechanical Engineering.

David’s Keynote Topic is: “Energy Reduction and Performance Maximization Through Improved Cooling” We had a chance to catch up with David on the phone, to ask him to let our readers know about why he chose his topic and what he hopes his listeners will take away from his presentation.

ATS:    David, why did you choose this topic?
Today, thermal engineers are given a semiconductor and told to maintain it at a certain temperature, 85 C or whatever, and I think this is true for those in other areas of thermal management as well, such as LED and Photovoltaic.  Here’s a device or component, now create a thermal management solution that keeps the devices junction temperature at the specified point.

But now, it looks like temperature is being a variable rather than a constant.  If you look at the International Technology Roadmap for Semiconductors, they have the high performance microprocessor junction temperature dropping from today’s 95 C to 70 C by the year 2024.   It’s only an average of 2 degrees per year decrease but taken as a whole, it’s a large drop that thermal professionals have to design to.

The other trend we are see is regarding power density.  Power density may more than double over that same time frame of 2011 to 2024.  So, as thermal engineering professionals, we are getting a bit constrained in terms of the higher power density and the lower head room.  Now, if your environment is, say, a 45 degree C environment, that drops your head room down from 50 degrees to 25 degrees, so that’s exactly half the temperature differential.  So the job has become somewhere on the order of 4 to 5 times more difficult.

The magnitude of the thermal resistance of the path from junction to ambient will have to go down by a factor of 4 to 5 over the next 15 years, which is not out of line with what has happened in the past 15 years, its just that our profession doesn’t currently have a lot of easily implementable solutions to get there.

The other thing we need to consider is microprocessor leakage current.  The relative sensitivity of temperature to leakage current is becoming very strong.  For example, in some process nodes you might have had to drop the temperature by 40 to 50 degrees in order to successfully cut the leakage power in half.   And now that number is getting to be more like 20 to 25 degrees.  So that means that the ability to make a given percentage cut in power consumption is slightly easier now with improved thermal management because you have to go down a lower temperature differential to get the same energy savings.  Of course the concentrated Photovoltaic and LED lighting also have their own performance vs. temperature curves as well in terms of efficiency.  Everything runs better when it’s cooler.  But, how much cooler can you afford to make your device or system and still come out ahead; that’s the question.

Read the rest of this entry »

ATS Thermal Team Shares Heat Sink Secrets in Thursday 2/24 Webinar

February 23, 2011

How do ATS engineers determine the best heat sink for an application?   Well, we’ll tell you if you attend our industry hit webinar, “Heat Sink Selection Made Easy” being held Thursday, February 24, 2PM EST.

Here’s what we’ll be covering:

Choosing the right heat sink the first time is essential. With so many application requirements and heat sink options, this can be a daunting task. In this webinar, attendees will learn about the importance of system airflow and its impact on heat sink design; attachment methods and how to solve thermal and mechanical design challenges; and how to make the right off-the-shelf or custom heat sink choice for your application and budget.

And here’s what our attendees are saying about our webinars:

“I enjoy your webinars.  I usually don”t catch them live but view the archived versions (very helpful with schedule conflicts).  I also attended one of Dr. Azar”s thermal management classes and was very impressed with his and your company”s work.”

“Thanks again to you and Dr. Azar on a nicely done Webinar on Thermal management overview.”

“I really value the knowledge that is shared within the thermal field by ATS.”

To join us simply click to “Heat Sink Selection Made Easy” being held Thursday, February 24, 2PM EST

Heat Sink Types: The Pros and Cons (part 2 of 2)

February 22, 2011

In Part 1 of our 2 part series on Heat Sink Types, we covered the following heat sink types: Extruded, Stamped, Bonded Fin, and Folded Fin.  Here in part 2, we’ll  look at active heat sinks, forged, swaged, single fin assembly and skived.  At the end, we’ll have a concise cheat sheet for you for easy reference.

Active Heat Sinks are those that have some kind of air mover on them.  This might be a fan or blower, and generally it is attached in some way to the heat sink.   The air move provides local air helping to cool down a semiconductors hot spot.   Many active heat sinks are often seen cooling high end graphics processors (GPUs) on graphics boards.  The performance of this kind of heat sink is high.  Generally speaking though it’s not a terrific solution long term.   Air movers are made up of moving parts (fan, bearings, motor) and while rated as long as they can, the truth is these air movers can break, rendering the underlying heat sink less than effective.   These solutions can tend to be costly as well.

Forged Heat Sinks conjure up the image of a blacksmith forming metal into a heat sink, but, in today’s modern world, forging is done by compressing a metal, in this case aluminum or copper.   Forged heat sinks may be used in a wide variety of applications.  They are medium performing heat sinks that are generally inexpensive to make.  Their only real limitation is they are somewhat limited in design and air flow management.

Swaged Heat Sinks are made by a swaging manufacturing process, which is a cousin to the forging process.  The swaging process involves forming the metal to a die.  Swaged heat sinks generally are very good performers and good for high power applications, that is,  power supplies, and other such equipment power equipment.  Swaged heat sinks tend to be bulky with a limited ability to manage air flow.

Single Fin Assembly Heat Sinks are versatile for all applications.  Their performance can scale from low to high performing.  Some of the reasons why thermal engineers use them is because single fin assembly heat sinks are light weight and feature low profiles, so they be deployed in tight spaces.  The main drawback is that they can be on the pricey side.

Skived Heat Sinks are those that are produced using the skiving process.  The skiving process basically takes a block of metal, often copper, and then create fins by making very fine cuts from that block.   Skived heat sinks can be used in many applications requiring medium to high performance.   The skiving process produces heat sinks with very high fin density, creating a good deal more surface area for heat dissipation.  A drawback though is the thick base often seen in skived heat sinks, higher weight and the heat sinks needing to be placed properly for air flow direction

That wraps up our 2nd part of this two part series.  To get a copy of the companion cheat sheet for this information, simply click this link:  “Heat Sink Types Cheat Sheet

Need a heat sink like the ones we discussed here?  Then please check out our eSHOP to purchase online, visit our heat sink section to see our complete list, or email us at sales.hq@qats.com with your questions and we’ll respond as quick as we can!

And don’t forget our QoolPCB program, Cool an entire PCB, all heat sinks included,  for $50!!

Heat Sink Types: The Pros and Cons (part 1 of 2)

February 21, 2011

At ATS we design many heat sinks.  In fact, as of today, we have over 4000 different heat sink designs in our library, plus all our off the shelf designs.   It’s likely we have designs that, with minor modifications will fit any thermal challenge.   But despite having over 4000+ designs in our  library, there are some very basic designs that form the basis for all the variations in the market.  In this two-part series, we want to cover these basic designs and give you the pros and cons.  At the end of our series, we’ll have a concise cheat sheet for you for easy reference.  Here in part 1 we’ll talk about the following heat sink types: Extruded, Stamped, Bonded Fin, and Folded Fin.

Extruded heat sinks are the “utility infielder” of our industry.  They are relatively inexpensive, once a design is made the manufacturing is highly automated, and, in most cases, aluminum is the material used.  Aluminum is cheap and a relatively good thermal conductor.   They are used for most general applications, depending on the design, fin pitch and base thickness they can be low to high performers, and, as I mentioned earlier, they are cost effective.  The basic con is they are limited in their dimensions being that they are based on an aluminum extrusion with a given width.

Stamped heat sinks are literally made from a piece of metal being stamped out in a press.  A tool is made to the form of the heat sink, then, metal is moved through a stamping machine and the stamp creates the heat sinks.  This too is a highly automated process and, as you might guess, once the heat sink design is complete and the prototypes OK’d, then the actual production is a relatively “simple”.   Stamped heat sinks are generally use for low power applications since they are typically low in performance.  They are cheap, even less expensive than extruded heat sinks.

Bonded fin heat sinks are generally geared towards physically large applications that require moderate performance.   Bonded fin heat sinks are made by bonding individual fins of metal to a base.  The bonding can be done by a thermal epoxy (somewhat cost-effective) or by brazing (expensive).    The main advantage to this type of heat sink is it can be used for large applications, such as a DC-DC Brick, or an electric welder.  The main drawback is manufacturing process isn’t automated on the scale of stamped, extruded, or folded fin heat sinks, resulting in a high cost for bonded fin.

Folded fin heat sinks are best when there is ducted air, that is, air flow is directed through a duct of some kind directly at the heat sink.   Fin pitch can be optimized in the manufacturing process making this kind of heat sink, with ducted air flow, very high performing. Also, because the heat sink material is folded, there can be a big increase in surface area over which heat can be dissipated.  Fold fin heat sinks have high heat flux density [1].  The drawbacks to this type of heat sink are the cost including manufacturing and ducting necessary in your system.    In some cases, plastic can be used to create a folded fin heat sink.

In part 2 of our 2 part series on heat sink types, we’ll  look at active heat sinks, forged, swaged, single fin assembly and skived.

Need a heat sink like the ones we discussed here?  Then please check out our eSHOP to purchase online, visit our heat sink section to see our complete list, or email us at sales.hq@qats.com with your questions and we’ll respond as quick as we can!

And don’t forget our QoolPCB program, Cool an entire PCB, all heat sinks included,  for $50!!



[1] Heat Flux or Thermal Flux is the rate of heat energy transfer through a surface.   Heat flux density is the heat flux unit per area http://en.wikipedia.org/wiki/Heat_flux

Rapid Prototyping and High Volume Manufacturing Through ATS Manufacturing Division

February 10, 2011

ATS manufacturing services include high precision, high capacity capabilities in metal and plastics fabrication that includes:

§ Metal and Plastic Extruding
§ Metal Stamping
§ CNC Machining
§ Sheet Metal and Plastic Forming
§ Plastic Welding

Your project can be submitted on-line through our on-line quote tool!

You can learn more about ATS’s manufacturing services here Rapid Prototyping and High Volume Manufacturing Through ATS Manufacturing Division

You may also contact us at 781-769-2800, email: sales.hq@qats.com or visit qats.com