Tag Archives: Advanced Thermal Solutions

Cooling Wide-Bandgap Materials in Power Electronics

Posted on June 15, 2018 by | Leave a comment

Engineers are always looking for an edge in their designs to extract as much power and performance as possible from a system, while attempting to meet industry trends in miniaturization. In the power electronics industry, this has required an examination of the materials being used to overcome inherent limitations from heat, voltage, or switching speed.

Cooling Wide-bandgap materials

Engineers are using wide-bandgap materials to expand the capabilities of power electronics, pushing them beyond the thermal and electrical limits of silicon-based components.(Background image created by Xb100 – Freepik.com)

For years, silicon was the answer for the power electronics market, but in the past decade there has been a growing movement towards wide-bandgap materials, particularly silicon carbide (SiC) and gallium nitride (GaN). Wide-bandgap materials have higher breakdown voltage and perform more efficiently at high temperatures than silicon-based components. [1] Recent research indicated, “For commercial applications above 400 volts, SiC stands out as a viable near-term commercial opportunity especially for single-chip current ratings in excess of 20 amps.” [2] This efficiency allows systems to consume less power, charge faster, and convert energy at a higher rate.

A recent article from Electronic Design explained that SiC power devices “operate at higher switching speeds and higher temperatures with lower losses than conventional silicon.” SiC has an internal resistance that is 100 times lower than silicon and a breakdown electric field of 2.8 MV/cm, which is far higher than silicon’s 0.3 MV/cm, meaning that SiC components can handle the same level of current in smaller packages. [3]

Engineers use the new material to produce systems with higher power-density and energy efficiency. While some industries have adopted new materials quicker than others, recent research from Yole Développement, a semiconductor and advanced packaging company based in France, indicated that there has been a significant growth in the SiC market in recent years. The research placed the market at $200 million as of 2015 and said that the market would reach an inflection point in 2017. [4]

New Electronics wrote that silicon carbide technology had reached a “tipping point” where engineers would focus more attention on new materials than on silicon, “pushed by the space, weight and efficiency requirements of electric vehicles and hybrids and by some particular industrial applications.” [5] All About Circuits added, based on the Yole research, that SiC was the material of choice for “power factor correction (PFC) power supplies, chargers, photovoltaic inverters, and trains.” [6]

As evidence of the industry’s acceptance of wide-bandgap materials, JEDEC Solid State Technology Association, a leader in standards development for the microelectronics industry, announced in September that it formed a committee on Wide Bandgap Power Electronic Conversion Semiconductors with sub-committees for SiC and GaN. “GaN and SiC technologies are poised to benefit from the development of standards focused on quality and reliability, datasheets, and test methods,” said Tim McDonald, Senior Director, GaN Applications and Marketing at Infineon Technologies. [7]

Industry leaders such as Texas Instruments (TI), Infineon, and Wolfspeed have signed on to the JEDEC committee and have already established products based on SiC technology. For instance, Infineon has released CoolSiC™ semiconductor solutions that include MOSFET, Schittky diodes, and hybrid modules. [8] ROHM Semiconductor recently announced that it had produced full SiC power modules that it claims reduces switching losses by 64 percent at 150°C. The company also announced that it is supplying power modules for the Venturi Formula E racing team. [9]

At the recent APEC 2018 show in San Antonio, sponsored by the PSMA (Power Sources Manufacturers Association), TI unveiled a new reference design (pictured below) for an HEV/EV onboard charger that used SiC-isolated gate drivers. [10]

ATS cold plates were on display at the TI booth, as a thermal solution for a new TI design. (Advanced Thermal Solutions, Inc.)

Thermal Management Concerns for SiC

SiC (and GaN) is clearly not just the future of semiconductor technology, it is also the present, but while wide-bandgap material allows components to perform at higher temperatures, there are thermal management concerns that engineers need to consider when designing the devices into a system. While SiC and other wide-bandgap materials may be able to withstand high temperatures, there are potential performance issues, such as higher rates of switching losses, and researchers still recommend that SiC dies operate at temperatures lower than 100°C for best efficiency. [11]

Higher temperature limits mean that, in theory, less complex cooling systems are required, which also means that SiC component packaging can be smaller since it no longer needs to account for larger, more intricate thermal management designs. It also means potential cost- and energy-savings for designers. But, the higher heat loads and the desire for smaller packaging mean passive, air cooling techniques are unlikely to accommodate the thermal management needs of the system. Liquid cooling is usually required, particularly the use of liquid cold plates to increase the rate of heat transfer to the ambient.

A recent presentation by SatCon Applied Technology showed that, despite higher power outputs, SiC components required smaller thermal contact areas and suggests the use of cold plates (copper in this particular example) to achieve the necessary cooling. [12] This was backed up by research from the European Research Council, which reported that active thermal management systems improved the performance of power electronics systems. [13]

Research from Cal Tech and the Jet Propulsion Laboratory (Pasadena, Calif.) explored the use of novel thermoelectric (TEC) microcoolers at the device level that provided spot cooling at higher heat fluxes than standard passive heat sinks. [14] According to researchers, the use of diamond or aluminum substrates enhanced the thermal performance of the microcoolers and thick-film coolers were able to achieve power densities greater than 100 W/cm2.

As noted in a research report by the National Renewable Energy Lab, while wide-bandgap materials can withstand much higher junction temperatures, those high heat loads can have a detrimental effect on other components in a system. Increasing the temperature of the system as a whole can lead to more failures, switching losses, and other issues for components that are not built to withstand high-temperature operation. Therefore, cooling needs to take not only a device-level but also system-level outlook. [15]

The NREL research suggested the following tactics for cooling SiC: using thermal interface material (TIM) that has low thermal resistance and is “reliable at functional temperatures,” using microchannels in cold plates to lower device junction temperatures, enhancing the surface and including “turbulence promoters” in the module, and incorporating both advanced manufacturing techniques and “multiple mode cooling” at the system level.

This slide from the presentation by the NREL explains how thermal management of wide-bandgap materials encompassed device-level, module-level, and system-level solutions. (NREL)

SiC has found a niche in the automotive world where the material is frequently mentioned in reports of new designs for electric vehicle batteries, as well as brake components and other components in high-heat environments. Some recent studies have gone beyond standard liquid cooling to include jet impingement cooling, which demonstrated significant thermal enhancement. According to a 2015 study, simulations demonstrated that a commercial, off-the-shelf (COTS) cold plate reduced the junction temperature of an SiC power module operating at a design heat load of 151 W from 290°C to 215°C. A COTS microchannel heat exchanger reduced the junction temperature to 215°C and a jet impingement-cooled heat exchanger lowered the junction temperature to 169°C at the same flow rate. [16]

The European Commission’s Community Research and Development Information Service (CORDIS) recently closed its SMARTPOWER project that brought together 15 partners from seven countries to examine the use of SiC and GaN technologies in industrial power devices. [17] The research led to the creation of forced cooling solutions with TEC modules to enhance heat sink thermal performance by as much as 200%, dropping device junction temperature from 250°C to 125°C. The research also developed enhanced TIM composed of vertically-aligned carbon nanotubes that increased heat transfer away from the devices, as part of novel 3-D packaging solutions.

Advanced Thermal Solutions, Inc. (ATS) continues to work on thermal solutions to meet the latest developments in power electronics. ATS recently released a new line of high-performance liquid cold plates that provide 30% improved performance compared to other commercially-available cold plates. An innovative, internal fin array with an optimized aspect ratio makes ATS cold plates, available in aluminum or copper and easily customizable to meet specific size or thermal requirements, the perfect choice for cooling high-powered electronics, including wide-bandgap devices.

ATS cold plates are the perfect solution for cooling high-powered electronics, such as IGBT modules. (Advanced Thermal Solutions, Inc.)

ATS cold plates provide uniform surface temperature across an IGBT or other high-powered device and can be fitted to a variety of components including Semikron SemiTRANS® Case D56, Infineon 62 mm, Fuji Semiconductor M127, M234, and M235, Powerex 62 mm, Mitsubishi 62 mm, and Vincotech 62 mm packages among many others.

As wide-bandgap materials proliferate across the power industry, ATS has liquid cooling solutions that will ensure optimal thermal management. For example, the TI reference design mentioned above used a customized ATS cold plate to provide the necessary cooling.

Learn more about ATS liquid cold plates and its array of liquid cooling solutions at https://www.qats.com/Products/Liquid-Cooling/Cold-Plates.

References
1. https://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/50531/1/04267750.pdf
2. http://jss.ecsdl.org/content/2/8/N3055.short
3. http://www.electronicdesign.com/analog/making-jump-wide-bandgap-power
4. https://www.i-micronews.com/compound-semi-expertise/8113-yole-analysis-the-sic-power-electronics-market-will-reach-an-inflection-point-in-2017-but-growth-brings-supply-chain-worries.html
5. http://www.newelectronics.co.uk/electronics-technology/silicon-carbide-technology-reaches-tipping-point/151641/
6. https://www.allaboutcircuits.com/news/sic-chips-kickstart-a-new-era-in-power-electronics/
7. https://www.jedec.org/news/pressreleases/new-jedec-committee-set-standards-wide-bandgap-power-semiconductors
8. https://www.infineon.com/cms/en/product/power/silicon-carbide-sic/
9. http://www.rohm.com/web/global/groups/-/group/groupname/SiC%20
Power%20Devices
10. https://www.qats.com/cms/2018/04/19/ats-power-solutions-on-display-at-apec-2018/
11. https://hal.archives-ouvertes.fr/hal-01473614/file/REYNES_Thermal%20Management%20Optimization.pdf
12. http://www.sandia.gov/ess/docs/pr_conferences/2005/Casey.pdf
13. https://www.sciencedirect.com/science/article/pii/S0026271414002650
14. https://pdfs.semanticscholar.org/ef32/8d5d3e0f617ada86cc02d
96398be97d48775.pdf
15. https://www.nrel.gov/docs/fy15osti/63002.pdf
16. https://www.researchgate.net/publication/273394047_Liquid_Jet_Impingement
_Cooling_of_a_Silicon_Carbide_Power_Conversion_Module_
for_Vehicle_Applications
17. https://cordis.europa.eu/project/rcn/99996_en.html

For more information about Advanced Thermal Solutions, Inc. (ATS) thermal management consulting and design services, visit https://www.qats.com/consulting or contact ATS at 781.769.2800 or ats-hq@qats.com.

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Industry Developments: Heat Exchangers for Electronics Cooling

Posted on May 25, 2017 by | 1 comment

By Norman Quesnel, Senior Member of Marketing Staff
Advanced Thermal Solutions, Inc.

(This article will be featured in an upcoming issue of Qpedia Thermal e-Magazine, an online publication dedicated to the thermal management of electronics. To get the current issue or to look through the archives, visit http://www.qats.com/Qpedia-Thermal-eMagazine. To read other stories from Norman Quesnel, visit https://www.qats.com/cms/?s=norman+quesnel.)

Heat exchangers are thermal management tools that are widely used across a variety of industries. Their basic function is to remove heat from designated locations by transferring it into a fluid. Inside the heat exchanger, the heat from this fluid passes to a second fluid without the fluids mixing or coming into direct contact. The original fluid, now cooled, returns to the assigned area to begin the heat transfer process again.

The fluids referred to above can be gases (e.g. air), or liquids (e.g. water or dielectric fluids), and they don’t have to be symmetrical. Therefore, heat exchangers can be air-to-air, liquid-to-air, or liquid-to-liquid. Typically, fans and/or pumps are used to keep these heat transfer medium in motion and heat pipes may be added to increase heat transfer capabilities.

Figure 1 shows a basic heat exchanger schematic. A hot fluid (red) flows through a container filled with a cold fluid (blue) but the two fluids are not in direct contact.

Heat Exchanger

Figure 1. In a Simple Heat Exchanger Heat Transfers from the Hot (Red) Fluid to the Cold (Blue) Fluid, and the Cooler After Fluid Re-Circulates to Retrieve More Heat. [1]

One example of a common heat exchanger is the internal combustion engine under the hood of most cars. A fluid (in this case, liquid coolant) circulates through radiator coils while another fluid (air) flows past these coils. The air flow lowers the liquid coolant’s temperature and heats the incoming air.

Applied to electronics enclosures, heat exchangers draw heated air from a cabinet, cool it, and then return the cooled air to the cabinet. These heat exchangers should be designed to provide adequate cooling for expected worst case conditions. Typically, those conditions occur when the ambient is the highest and when electrical loads through the enclosure are very high. Under typical conditions, heat exchangers can cool cabinet interiors to within 5°F above the ambient air temperature outside the enclosure.

Air-to-Air

Air-to-air heat exchangers have no loops, liquids or pumps. Their heat dissipation capabilities are moderate. Common applications are in indoor or outdoor telecommunications cabinetry or in manufacturing facilities that don’t have a lot of dust or debris.

Air-to-air heat exchangers provide moderate to good cooling performance. They don’t allow outside air to enter or mix with the air inside the enclosure. This protects the enclosure’s contents from possible contamination by dirt or dust, which could damage sensitive electronics and electrical devices and cause malfunctions.

An example of higher performance, air-to-air heat exchangers is the Aavid Thermacore HX series. These heat exchangers feature rows of heat pipes that add effective, two-phase heat absorbing properties when moving hot air away from a cooling area. The liquid inside the heat pipes turns to vapor. This transition occurs inside a hot cabinet. (See Figure 2)

The vapor travels to the other end of the heat pipe, which is outside the cabinet. Here it is cooled by a fan, transitions back to liquid form, and cycles back inside the cabinet environment.

Heat Exchangers

Figure 2. An Air-to-Air Heat Exchanger with Heat Pipes Extending Inside (top) and Outside (bottom) a Cabinet. Internal Heat is Transferred Outside the Enclosure. (Aavid Themacore) [1]

Other air-to-air heat exchangers feature impingement cooling functionality that can provide better performance than using heat pipes. Aavid Thermacore’s HXi Impingement core technology uses a folded fin core that separates the enclosure inside and outside. A set of inside fans draws in the hotter, inside air and blows it toward the fin core. This inside impingement efficiently transfers the heat to the fin core. Similarly, a set of outside fans draws in the cooler, ambient air and blows it toward the outer side of the fin core removing the waste heat. See Figure 3 below.

Heat Exchangers

Figure 3. Air-to-Air Heat Exchangers with Double-Sided Impingement Cooling Technology Can Move Twice the Heat Load of Conventional Exchangers. (Aavid Themacore) [3]

Liquid-to-Air

In some electronic cabinets, high power components can’t be cooled by circulating air alone or the external ambient air temperature is not cool enough to allow an air-to-air heat exchanger to solve the problem unaided. In these applications, liquid-to-air heat exchangers provide additional cooling to maintain proper cabinet temperatures.

For example, in a situation where heat is collected through a liquid-cooled cold plate attached directly to high power components. Even with the cold plate, the ambient air external to the cabinet is not cool enough to maintain the internal cabinet temperature at an acceptable or required level. Here, a liquid coolant in an active liquid-to-air heat exchanger can be used to cool the enclosure.

Heat Exchangers

Figure 4. Tube-to-Fin, Liquid-to-Air Heat Exchangers Provide High-Performance Thermal Transfer. [4] (Advanced Thermal Solutions, Inc.)

Advanced Thermal Solutions, Inc. (ATS) tube-to-fin, liquid-to-air heat exchangers have the industry’s highest density of fins. This maximizes heat transfer from liquid to air, allowing the liquid to be cooled to lower temperatures than other exchangers can achieve. All tubes and fins are made of copper and stainless steel to accommodate a wide choice of fluids.

Available with or without fans, ATS heat exchangers are available in a range of sizes and heat transfer capacities up to 250W per 1°C difference between inlet liquid and inlet air temperatures. They can be used in a wide variety of automotive, industrial, HVAC, electronics and medical applications. [4]

Heat Exchanger

Figure 5. Small, Light-Weight Liquid-to-Liquid Heat Exchanger Provides Efficient Cooling Performance. [5]

Lytron’s liquid-to-liquid heat exchangers are only 10-20% the size and weight of conventional shell-and-tube designs. Their internal counter-flow design features stainless steel sheets stamped with a herringbone pattern of grooves, stacked in alternating directions to form separate flow channels for the two liquid streams. This efficient design allows 90% of the material to be used for heat transfer. Copper-brazed and nickel-brazed versions provide compatibility with a wide range of fluids. [5]

Nanofluids

The development of nanomaterials has made it possible to structure a new type of heat transfer fluid formed by suspending nanoparticles (particles with a diameter lower than 100nm). A mixture of nanoparticles suspended in a base liquid is called a nanofluid. The choice of base fluid depends on the heat transfer properties required of the nanofluid. Water is widely used as the base fluid. Experimental data indicates that particle size, volume fraction and properties of the nanoparticles influence the heat transfer characteristics of nanofluids. [5]

When compared to conventional liquids, nanofluids have many advantages such as higher thermal conductivity, better flow, and the pressure drop induced is very small. They can also prevent sedimentation and provide higher surface area. From various research, it has been found that adding even very small amounts of nanoparticles to the base fluid can significantly enhance thermal conductivity.

Heat Exchangers

Figure 6. 3D Design of Curved Tube Heat Exchanger. Increased Turbulence and Velocity Increases Heat Transfer Rate. [6]

A recent paper by Fredric et al. proposes a theoretical heat exchanger with curved tubes and with nanofluids as the coolant. Nanofluids in place of regular water provide improved thermal conductivity due to the increased surface area. The heat transfer rate is further improved using curved tubes in place of straight tubes because the used of curved tubes increases the turbulence and fluid velocity, which helps increase the heat transfer rate. [6]

References
1. Advanced Thermal Solutions, Inc., https://www.qats.com/Products/Liquid-Cooling/Heat-Exchangers.
2. Aavid Thermacore, http://www.thermacore.com/documents/system-level-cooling-products.pdf.
3. Aavid Thermacore, http://www.thermacore.com/products/air-to-air-heat-exchangers.aspx.
4. Advanced Thermal Solutions, https://www.qats.com/Products/Liquid-Cooling/Heat-Exchangers.
5. Kannan, S., Vekatamuni, T. and Vijayasarathi, P., “Enhancement of Heat Transfer Rate in Heat Exchanger Using Nanofluids,” Intl Journal of Research, September 2014.
6. Fredric, F., Afzal, M. and Sikkandar, M., “A Review on Shell & Tube Heat Exchanger Using Nanofluids for Enhancement of Thermal Conductivity,” Intl. Journal of Innovative Research in Science, Engineering and Technology, March 2017.

For more information about Advanced Thermal Solutions, Inc. thermal management consulting and design services, visit www.qats.com or contact ATS at 781.769.2800 or ats-hq@qats.com.

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Utilizing Fans in Thermal Management of Electronics Systems

Posted on March 6, 2017 by | 12 comments

Fans in Thermal Management

There are different types of fans that are used in thermal management of electronics with tube axial fans being the most common. (Wikimedia Commons)


The ongoing trend in the electronics industry is for increasingly high-powered components to meet the ever-growing demands of consumers. Coupled with greater component-density in smaller packages, thermal management is more and more of a priority to ensure performance and reliability over the life of an electronics system.

As thermal needs have grown, engineers have sought out different cooling methods to supplement convection cooling. While options such as liquid cooling have grown in popularity in recent years, still one of the most common techniques is to add fans to a system.

Through the years, fan designs have improved. Fan blades have been streamlined to produce great flow rate with less noise and fans have become more power-efficient to meet the desires of customers trying to use less resources and save costs.

While much has changed in the presentation of fans, there are many basic concepts that engineers must consider when deciding how to implement fans in a project.

This is part one of a two-part series on how to select the best fan for a project. Part one will cover the types of fans that can be used. Part two, which can be found at https://www.qats.com/cms/2017/03/10/analysis-of-fan-curves-and-fan-laws-in-thermal-management-electronics, will cover fan laws and analyzing fan curves.

COMMON TYPES OF FANS AND BLOWERS

As described by Mike Turner of Comair Rotron in an article for Electronics Cooling Magazine, “All You Need to Know About Fans,” fans are essentially low pressure air pumps that take power from a motor to “output a volumetric flow of air at a given pressure.” He continued, “A propeller converts torque from the motor to increase static pressure across the fan rotor and to increase the kinetic energy of the air particles.”

In a white paper from Advanced Thermal Solutions, Inc. (ATS) entitled, “Performance Difference Between Fans and Blowers and Their Implementation,” it was added that fans are at their core, dynamic pumps. The article added, that in dynamic pumps “the fluid increases momentum while moving through open passages and then converts its high velocity to a pressure increase by exiting into a diffuser section.”

The biggest difference between a fan and a blower is the direction in which the air is delivered. Fans push air in a direction that is parallel to the fan blade axis, while blowers move air perpendicular to the blower axis. Turner noted that fans “can be designed to deliver a high flow rate, but tend to work against low pressure” and blowers move air at a “relatively low flow rate, but against high pressure.”

The three types of fans are centrifugal, propeller, tube axial, and vane axial:

• In centrifugal fans, the air flows into the housing and turns 90 degrees while accelerating due to centrifugal forces before being flowing out of the fan blades and exiting the housing.
• Propeller fans are the simplest form of a fan with only a motor and propellers and no housing.
• Tube axial fans, according to Turner, are similar to a propeller fan but “also has a venture around the propeller to reduce the vortices.”
• Vane axial fans have vanes trailing behind the propeller to straighten the swirling air as it is accelerated.

The most common fans used in electronics cooling are tube axial fans and there are a number of manufacturers creating options for engineers. A quick search of Digi-Key Electronics, offered options such as Sunon, Orion Fans, Sanyo Denki, NMB Technologies, Delta Electronics, Jameco Electronics, and several more.

Fans in Thermal Management

A fan is added to a heat sink on a PCB in order to increase the air flow and heat dissipation from the board component. (Advanced Thermal Solutions, Inc.)

FACTORS TO CONSIDER WHEN PICKING A FAN

When selecting a fan, engineers must consider the specific requirements of the system in which they are working, including factors such as the necessary airflow and the size restrictions of the board or the chassis. These basic factors will allow engineers to search through the many available options to find a fan that fits his or her needs.

In addition, engineers may look towards combining multiple fans in parallel or in a series to increase the flow rate across the components without increasing the size of the package or the diameter of the fan.

Parallel operation means having two or more fans side-by-side. When two fans are working in parallel, then the volume flow rate will be increased, even doubled when the fans are operating at maximum. Turner added. “The best results for parallel fans are achieved in systems with low resistance.”

In a series, the fans are stacked on top of each other and results in increased static pressure. Unlike parallel operations, fans in a series work best in a system with high resistance.

The ATS white paper noted, “In real situations, the fans may interfere with each other. The end results is a lower than expected performance.” Turner warns that in either parallel or series configurations there is a point in the combined performance curve that should be avoided because it creates unstable and unpredictable performance, but analyzing fan performance and fan curves will be covered in more detail in part two of the blog.

Efficiency is a major factor when selecting a fan. As noted in an article from Qpedia Thermal eMagazine, “A large data center contains about 400,000 servers and consumes 250 MW of power. It has been estimated that about 20% of the total power supplied to a high end server is consumed by fans.”

Clearly, finding a fan that can work efficiently with lower power will save a considerable about of resources. The article details several methods for creating efficiency in designing a system that includes fans:

“Fan power consumption is traditionally reduced by controlling the motor speed to produce only the airflow required for adequate cooling, rather than operating continuously at full speed. Significant energy savings can be achieved beyond this technique through fan efficiency increase. Optimizing the motor and electronic driver, increasing fan aerodynamic efficiency through careful redesign, and optimizing fan-system integration are three ways of achieving this.”

Read more about the techniques for achieving efficiency at https://www.qats.com/cms/wp-content/uploads/2015/03/Designing_Efficient_Fans_for_Electronics_Cooling
_Applications.pdf.

CLICK HERE FOR PART II.

To learn more about Advanced Thermal Solutions, Inc. consulting services, visit www.qats.com or contact ATS at 781.769.2800 or ats-hq@qats.com.

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Posted in cooling, Fan, Fans, PCB, thermal management

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Case Study: LED Solution for Outdoor Canopy Array

Posted on November 30, 2016 by | 1 comment

Advanced Thermal Solutions, Inc. (ATS) was approached by a company interested in a new design for an outdoor LED unit that would be installed in gas station canopies. The original unit was bolted together and contained a molded plastic shroud that held the LED array, the PCB, and an extruded aluminum heat sink.

ATS engineers designed an aesthetically pleasing alternative that utilized natural convection cooling, while increasing the number of the LEDs in the array and its power. The engineers met the customer’s budget and thermal performance requirements.

• Challenge: Create an outdoor canopy device that would increase the number of LED in the array, increase power to maximum of 120 watts, and increase lumens, while cooling the device through natural convection.

• Chip/Component: The device had to hold an LED array and the PCB that powered it.

• Analysis: Analytical modeling and CFD simulations determined the optimal fin efficiency to allow air through the device and across the heat sink, the spreading resistance. The weight of the device was also considered, as it would be outside above customers.

• Solution: An aesthetically-pleasing, one-piece, casted unit with built-in electronics box for LED array and PCB was created. There was one inch of headroom between the heat sink and the canopy to allow for heat dissipation and the casting would allow heat transfer as well as allow air to flow through the system.

• Net Result: The customer was able to add LEDs to the array and increase power. The new unit also simplified the manufacturing process and cut manufacturing costs.

For more information about Advanced Thermal Solutions, Inc. thermal management consulting and design services, visit www.qats.com or contact ATS at 781.769.2800 or ats-hq@qats.com.

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ATS holding webinar on Thermal Management of Medical Electronics

Posted on November 11, 2016 by | Leave a comment
Medical Webinar

DR. Kaveh Azar, founder, CEO and President of Advanced Thermal Solutions, Inc. (ATS), will present a free webinar on “Thermal Management in Medical Electronics” on Dec. 15, 2016.

On Thursday, Jan. 26, Advanced Thermal Solutions, Inc. (ATS) will host a free, online webinar on “Thermal Management of Medical Electronics”. The hour-long webinar will begin at 2:00 p.m. and there will be 30 minutes of question and answer time after its completion.

The webinar will be presented by thermal management expert Dr. Kaveh Azar, the CEO, President and founder of ATS. Dr. Azar will speak about the unique challenges that are present in finding a thermal solution for medical electronics and the importance of including thermal management in the design process.

The object of all thermal management is to ensure that the device junction temperature, the hottest point on a semiconductor, stays below a set limit. While this is true for all electronic systems, medical electronics pose unique thermal challenges that have to be overcome to meet the junction temperature requirements.

Medical electronics could have stringent material selection. For example, copper is a common metal chosen in thermal management, but can cause irritation or a neurodegenerative condition for patients and has to be used carefully. In addition, medical electronics may have spatial constraints, such as forceps that have only 2-4 millimeters of width, which is a constrained space with very little airflow.

Other challenges presented by medical electronics include the need for constant, reliable repeatability; temperature reliability within a range; and in some cases specific FDA requirements.

Dr. Azar will address each of these issues and more. To register for the free webinar on Thursday, Jan. 26, visit http://www.qats.com/Training/Webinars.

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Posted in Consulting, Medical, thermal management, Webinar

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