We’ll be hosting another of our monthly webinar on 4-15-21 at 2 PM EST. This one covers how to choose the right heat sink attachment for component packages of all sizes and shapes. Our speaker will be Product Engineering Manager, Greg Wong.
Choosing the right heat sink is part of deploying a good thermal management solution, the other part is the attachment method. Whether clip, push pin, z-clip, or other, the attachment has an important impact on how effective the thermal solution is. This webinar will cover these issues including attachments for rectangular packages increasingly used in SoC and SiP packages. A handy technical reference sheet and white paper on attachment types will be provided to those who register. This webinar, presented by ATS Product Engineering Manager, Greg Wong and will address all these issues and more. The webinar is 30 minutes in length with time for questions and answers afterward online and after the webinar concludes. The webinar is no charge to attend, but, we do ask you to register:
By Norman Quesnel, Senior Member of Marketing Staff Advanced Thermal Solutions, Inc. (ATS)
Ultra-low temperature (ULT) freezers, like the VOSTOK series from ATS, run at high power. Many models require more than 1.5 KW to maintain their extremely low (-40 to -86°C) temperature range. Straying from these levels of coldness can compromise the biological materials, such as vaccines, that require these storage conditions.
That is why different ‘coldness security’ features are built
into VOSTOK freezers to help prevent temperature rise. These include door
locks, and protective covers on power switches. Alarm systems call fast
attention to wide range of issues from power failure, to temperature rises, to
ajar doors. Password protection keeps unauthorized users away from system
One of the most important needs for coldness security is a backup cooling system. These separate refrigerator units switch from standby to active cooling modes when a freezer is unexpectedly powered down.
For certain VOSTOK freezers an optional carbon dioxide standby system provides refrigeration for cooling equipment in the event of a power failure or cooling failure to ensure that the temperature inside the refrigeration equipment is maintained within the required range.
When the refrigeration equipment is working normally, the CO2 (liquid nitrogen) backup system is in standby state. When the cooling equipment is powered off, the carbon dioxide (liquid nitrogen) backup system uses its own rechargeable battery to spray liquid CO2 (N2) through the partition into the refrigeration equipment.
The automatically spray-discharged coolant can retain a
temperate of -70°C for three hours. (See Standby System Controller image.) In
this time, auto alert services can respond and correct the issue or relocate
the internal samples.
By Norman Quesnel, Senior Member of Marketing Staff Advanced Thermal Solutions, Inc. (ATS)
The VOSTOK portable, ultra-low temperature (ULT) freezer features a lightweight, non-powered cooling system. When it comes to providing low temperatures, it is as capable as larger cabinets, easily reaching down to -86°C (-123°F).
This is achieved by using Stirling engine technology in place of more common compressor systems (too big, heavy) or using dry ice (not cold enough for many requirements). At just 30 lbs (13.5 K), the portable VOSTOK cooler, PortM80, is one-third lighter than many other portable coolers.
Stirling engines provide a sound method of energy conversion with useful qualities like high efficiency, high reliability, and easy and quiet operation. Stirling technology uses environmentally safe helium as its refrigerant. It has a linear motor and thermosiphon system that minimize moving parts and maximize reliability and working life. Its moving parts don’t wear out because gas bearings eliminate internal friction. The two moving parts, the piston and the displacer, expand and compress helium in the engine, absorbing heat from the thermosiphon, keeping the cabinet cold. They don’t wear out because the inert gas bearings eliminate internal friction.
Because of the unique Stirling technology, the PortM80 freezer easily absorbs vibration and transportation bumps. It can be equipped with multiple Stirling coolers. During pre-cooling, multiple Stirling coolers can be started at the same time to achieve shorter pre-cooling time, and during normal operation, it can be put into a multi-prepared mode.
Thanks in large part to Stirling
cooling the PortM80 freezer is a very useful method for keeping Pfizer’s
COVID-19 vaccine in its safe storage temperature. It safely keeps the vax that
way when it’s transported to locations where large cabinets can be used.
By Norman Quesnel, Senior Member of Marketing Staff Advanced Thermal Solutions, Inc. (ATS) Qpedia 107, Featured Article
Next-gen and brand new technologies are quickly
developing and already impacting life around the globe. These include
artificial intelligence, the Internet of Things, autonomous vehicles, virtual
reality, and smart buildings and cities.
Another advanced technology essential to all
these technologies is 5G communications.
5G is the 5th generation of mobile networks, a
significant evolution of today’s 4G LTE networks. 5G is being designed to meet
the exploding growth in data and connectivity needs of today’s modern, highly
populated society. It brings three major advances. First, it provides bigger channels
to speed up data downloads and uploads. It also reduces latency which improves
response times. And it connects many more devices at one time once, allowing
more sensors and smart devices. 
5G electronics hardware ranges from base stations to transceivers to handsets. And transitioning these to 5G has some drawbacks and limitations. Many are due to 5G’s faster, smaller wave transmissions. 5G frequencies are found in low-band, mid-band, and high-band ranges, which can be matched to various conditions and applications. Much of the 5G spectrum is in extremely high frequency (EHF) or millimeter wave (mmWave) frequencies.
Faster millimeter wave
frequencies are more susceptible to the environment. They have difficulty passing through walls and windows,
so indoor coverage is limited. And millimeter
wave communications can be susceptible to rain, fog and other atmospheric
interference. They also need shorter distances between the devices sharing
them. As a result, millimeter wave networks require more cells and base
stations, particularly in densely-populated areas with millions of connections.
Because each spectrum band has different radio properties, infrastructure hardware, such as towers and antennas vary accordingly. In the low band spectrum, the infrastructure and placement are relatively similar to current 4G deployments. In 5G’s mmWave range, towers are shorter, discrete, and more densely placed. Their antennas are designed for short distances and use techniques like beam-forming to overcome propagation shortfalls. Some antennas are designed to support new 5G-related technologies like massive MIMO that produce greater capacity out of the same spectrum. 
And, as with most high power electronic devices, thermal issues could also adversely impact performance. Much of the outdoor electronics in 5G network architecture must deal with heat (and cold) extremes, not only environmental but from their own high power, condensed packages and structures. And, some 5G handsets have shown susceptibility to higher ambient temperatures.
Fortunately, in most cases, thermal management techniques are already available to solve heat issues facing 5G communications devices.
Stations and Cells
Base stations, macro cells, micro cells, small cells and other
devices are all part of the dynamic cell phone infrastructure. Macro cells that
cover a wide area, micro cells are used for densification of coverage in highly
populated areas, and pico cells boost coverage within buildings These will need
upgrading or replacing to accommodate 5G. And many more will be needed to pass
along shorter reach mmWave signals. 
Relatively short-range mm wave frequencies need some kind of low-power antenna every 1,500 feet or so. This is a higher saturation than with macro cell sites now at work in many suburbs. The small, individual millimeter-wave cells are much less powerful than larger cell sites, but the high frequencies drop off so quickly with distance that you need more of them.
One of the major base station OEMs is Nokia. Their models typically include one or more cooling methods, depending on their application and location. The liquid-cooled Massive MIMO base station (below) is a third lighter and half the thickness of its predecessor. The smaller scale lets it better blend in with walls and buildings. By adding liquid cooling Nokia was able to remove internal cooling fins which had taken up a lot of space. 
A typical 5G base station can consume twice or
more the power of a 4G base station, and energy costs can grow even more at
higher frequencies, due to a need for more antennas and a denser layer of small
5G macro base stations may require several new,
continuously running, power-hungry components, including microwave or
millimeter wave transceivers, field-programmable gate arrays (FPGAs), faster
data converters, high-power/low-noise amplifiers and integrated MIMO
5G requires multiple, multi-element antennas. Current strategies for thermally managing mmWave antennas include forced air and liquid cooling. Despite being effective in removing the heat, active cooling systems with fans or pumps require the use of electricity and can make the system more complex and hard to maintain.
On the other hand, passive thermal management is a relatively cheaper and more energy-efficient solution. However, since the heat is removed only passively via natural convection using only heat spreaders or heat sinks, it is not easy to achieve thermal performance similar to that of the active counterparts unless there is sufficient surface area that is in contact with outside. 
addition to modifying and creating various cell stations to carry 5G, carriers
are also deploying edge computing resources to support such things as
low-latency applications and IoT services. Edge technologies
could one day make it feel like every 5G device is a supercomputer. Critical
data is processed extremely fast at the brink of the network, by edge devices.
Secondary systems and less urgent data are sent to the cloud and processed
When designing 5G into a router or other fixed-access device, thermal issues will be a greater cause for concern than for products that use LTE for wireless communications, even though the energy-per-bit might be less than LTE because of 5G’s greater bandwidth.
An example here is the Cradlepoint W2000-Series
5G wideband adapter. The edge device was thermally modeled and then equipped
with heat pipes to cool some internal components. Its aluminum case has
integral fins and a white, reflective coating. 
Another edge computing hardware focus involving 5G is to
support autonomous vehicles. Near real-time data transfer will be required for
safe driving because transfer of large amounts of data to a centralized data
processing plant will take too long, and this facility must use high-power AI
algorithms to process the data efficiently and accurately.
Edge devices onboard vehicles will face harsh environments and extreme temperatures. This means a need for both solid thermal management and physical protection as well. Such a use case could call for thermal management with a chassis. An example is the Arrow SAM Car chassis developed to both cool and protect electronics used for controlling a car.
5G phones will be in great
demand on a global basis in the near future. Ahead of all the 5G infrastructure
installs, many 5G phone models are already available from major providers. This
is not happening without growing pains. Some of the first 5G phones were found
to be very susceptible to hot weather. Because of the overheating they would
drop from 5G to 4G. This wasn’t isolated, but seen on tests of 5G phones from
several major providers. 
Thermal issues increasingly challenge smartphone makers as processors
get more and more powerful while phones get thinner and thinner. Some
solutions, short of putting vents everywhere, involve thermal paste. Other
conventional solutions could be heat absorbing materials and small heat pipes.
Samsung, Apple, and other companies can perform advanced thermal analysis to see exactly where hot spots occur, and devise strategies to mitigate them. These can range from better internal cooling solutions to thicker chassis or better thermal interface materials. Internal fans may be impractical for standard 5G phones, but even a very small fan could help with heat problems, at the cost of thickness, a bit of noise, and a little power. 
Data management may offer other remedies. Firmware could be
developed to manage power levels and their associated heat. As mentioned above,
it may be possible to have 5G phones offload some processing to nearby edge
devices. While this may reduce heat in the phone, it may not be possible if
different providers are running the edge gear and the phone’s operations.
Gaming smartphones are made to be super quick and super powerful, even compared to smartphones that already function at high speeds. Most phones can run hot when gaming intensively. But gaming phones have one advantage. They don’t need to look especially stylish, and so can get away with putting an air-cooling fan inside.
Nubia’s Red Magic 5G gaming
phone features a small internal spinning fan to drive cool air in and hot air
out. Nubia reports this results in cooling the phone by as much as 18 degrees
Celsius, both while in heavy use and while charging at a fast 55W rate. 
From base stations to cell phones, 5G communications can dramatically improve mobile communications among billions of connected users. And more than this, 5G is a core technology supporting the evolutions in computing, life science, transportation and a near limitless range of applications. Like all technologies, it has some obstacles to get past, including high temperatures and their adverse effects. But 5G is too strong of a technical global game changer not to find solutions to problems along the way.
ATS is hosting a free engineering webinar on Thursday, 3-18-21 titled “Heat Pipes & Vapor Chambers – How They Work and Their Deployment in Electronics Thermal Management”. In this in depth webinar, attendees will learn:
Equations and analytical modeling for heat pipes
References for more in-depth study
Learn about what a heat pipe and vapor chamber is and its function
Deployment examples and the thermodynamic cycle relative to deployment
Why use heat pipes and what the advantages are
Discussion of wick structure, the “pump” in a heat pipe or vapor chamber
The fluid, filling amount and fluid types
And much more.
The webinar is 60 minutes with a 30 minutes Q&A period. All questions will be answered either during the webinar or later.
Attendance is no cost but we do ask you to register at the link below:
We’ll be hosting another of our monthly webinar on 4-15-21 at 2 PM EST. This one covers how to choose the right heat sink attachment for component packages of all sizes and shapes. Our speaker will be Product Engineering Manager, … Continue reading →