Tag Archives: thermal management

ATS Webinar Selecting and Designing Liquid Cold Plates for Deployment in Electronic Systems

Advanced Thermal Solutions (ATS, Inc. www.qats.com) will be hosting a free webinar, led by Dr. Kaveh Azar, on selecting and designing liquid cold plates for deployment in electronic systems on August 26th at 2PM EST.

This webinar provides the best practices for implementing a liquid cooling system at the device level. Topics covered include:

  • When should you cool with liquid?
  • What is the right liquid cooling system to use?
  • What is a cold plate and how and when to best implement them

To join this webinar on August 26th, click to our web site to register here:  Selecting and Designing Liquid Cold Plates for Deployment in Electronic Systems

Vapor Chambers for Thermal Management: A Primer by Thermacore

Thermacore Vapor Chamber Heat Sink Thermacore’s Matt Connors has written up a nice primer on Vapor Chamber technology that’s well worth a read over at Design World Magazine. Among the points he notes:

  • Surface area alone is not enough with highly concentrated heat sources such as high-power electronic components. As the electronic components get smaller and the heat sinks base area increases, a large thermal heat spreading penalty is typically found in the base of the heat sink [ATS: meaning? you can only make a heat sink so big before it doesn’t work efficiently with concentrated heat sources]
  • To stay within the existing heat sink form factor and to reduce the thermal resistance of the larger base, the heat sink’s standard metallic base needs to be replaced with a conducting material. A vapor chamber can be used as the medium to spread heat in the base more efficiently.
  • Vapor chambers are essentially flat or planar heat pipes that use the principles of evaporation and condensation to produce a very high conductivity thermal plane. Vapor chambers are basically evacuated vessels with an internal wick and a working fluid. The wick helps transport the working fluid back to the evaporator surface without using moving parts. Once the fluid evaporates, it travels to the cooler section of the chamber, condenses in the wick, and the cycle continues.

Matt’s got some other choice words as well and his article is a great primer on this topic for our readers.

As Matt notes, vapor chambers are really flat heat pipes.ATS has some resources that can provide you some breadth of information to go with Thermacore’s primer, here’s three ATS Technical White Papers, all for free:

How to implement localized thermal management of electronics through the use of cold plates

Cold plates are “aluminum or other material plates containing internal tubing through which a liquid coolant is forced, to absorb heat transferred to the plate by transistors and other components mounted on it.”

Lytron is one of the best in the business at producing cold plates and their site is chock full of excellent information on the different types and uses.  Including some basic comparisons. The following cold plate graph, from Lytron, compares the normalized thermal resistances of different cold plate technologies, enabling thermal performances to be compared independently of the cold plate part geometries. The lower the thermal resistance, the better the performance of the cold plate. As many cold plates are customized, a range of typical values is shown for each cold plate technology. All cold plate performances are compared using water as the cooling fluid.

cold plate technology comparison for thermal management

Many thermal management applications in electronics require a cold plate to remove the heat from discrete components laid out on a printed circuit board (PCB). In these circumstances, it is more efficient that the liquid does not completely fill the cold plate, but is only transferred to areas that need to be cooled.  With this kind of cold plate design, the required volumetric flow rate of the coolant will be significantly lower than if the entire cold plate was filled with liquid. ATS’s thermal labs white paper, “Localized Cooling  Using Cold Plates” covers the math and method on how to do this.  Our white paper is free to our readers on the qats.com web site, just click to this link to download your own free copy of our white paper, “Localized Cooling  Using Cold Plates“

Laird Technologies Releases Thermoelectric Cooler Thermal Management Application Notes

Laird Technologies is known for a host of technologies including EMI shielding, wireless antenna’s and thermal management products. They have some pretty smart engineers at Laird and they’ve put some of those thoughts on paper to release a new set of Thermal Management application notes for Thermoelectric Coolers.

According to Laird’s official press release:

The application note describes why Thermoelectric Modules (TEMs) and Thermoelectric Assemblies (TEAs) are ideal thermal management solutions for many telecommunication applications such as laser diodes and laser pump diodes, cable television (CATV) laser diodes, avalanche photodiodes (ADPs), GPS backup cellular networks, and Battery Backup Unit (BBU) systems in base stations. A wide range of small-and medium-sized heat pumping TEMs and TEAs are beneficial to telecommunication device requirements by complying with excessively tight space constraints that are associated with most telecommunication equipment. They also provide extremely precise temperature regulation, allowing devices to function at peak performance while reducing overall equipment operating costs.

Sounds like great reading frankly and well worth our reader’s time to go visit.  To get your mitts on these important application notes, visit Laird’s site at this link, “Thermoelectric Assemblies and Modules for Telecommunications Applications“.

Our readers might also want a primer on thermoelectric modules.  ATS released such a white paper/primer on July 20th, 2010. You can download your own free copy from qats.com at this link, “Using Thermoelectric Coolers in Electronics Cooling“

ATS Labs Thermal Management White Paper: Using Thermoelectric Coolers in Electronics Cooling

Thermoelectric coolers (also known as thermoelectric device or thermoelectric module) are semiconductor modules which use the Peltier Effect to create a heat flux between the junctions of two different types of materials. Named after French physicist Athanase Peltier, the Effect shows that a temperature differential is created when DC current is applied across two dissimilar materials. (It is one of the three thermoelectric effects; the others are the Seebeck Effect and Thomson Effect)

A typical thermoelectric cooler is manufactured using two thin ceramic wafers with a series of N and P doped bismuth-telluride semiconductor material sandwiched between them. The ceramic material adds rigidity and the necessary electrical insulation. The N type material has excess electrons, while the P type material has a deficit of electrons. One N and one P make up a couple, as shown in Figure 1.

Thermoelectric Cooler for thermal managementWhen a DC current is applied to the circuit, the thermoelectric device can work as a cooler or heater depending on the currents direction. A thermoelectric cooler (TEC), or solid state heat pump transfers heat from one side of the device to the other side against the temperature gradient. Many products use thermoelectric coolers, including small refrigeration systems, CCD cameras, laser diodes and portable picnic coolers. They are also used in the thermal management of microprocessors, memory modules and other electronic devices.

ATS’s white paper covers much more on this topic, and you can get your own copy for free, by clicking to, “Using Thermoelectric Coolers in Electronics Cooling“.