The client requested a design for warming and cooling a headset. The device was to be installed in a headset with proper weight and size compatible with the size of the headset.
The main challenge in this project was the power source. Since a headset is a portable device, the power source also needs to be portable too.
In order to make an efficient design that could be used in different headsets, the MEEE design engineer suggested using a set of Peltier thermoelectric modules. A Peltier cooler, heater, or thermoelectric heat pump is a solid-state active heat pump which transfers heat from one side of the device to the other, with consumption of electrical energy, depending on the direction of the current.
Regarding the power requirement, the designer used Lipo batteries that could supply the requested voltage.
The small size of the enclosure enforced limitation on the number of batteries. By choosing the proper Peltier module, and defining the max and min ambient temperature, the current and voltage were calculated, and the electronic circuit for controlling voltage and current to achieve both the heating and cooling requirement was designed. The electronic circuit was designed in a way that consumed the minimum energy for powering Peltier modules,
Following the above calculations, six TE-31-1.0-1.3 Peltier module and lithium-ion polymer batteries with 3.7V LP503562 1200mah were used. This battery type was chosen so that the quality matched CE FCC ROHS certifications.
The TE-31-1.0-1.3 Peltier module had the following specifications
One of the advantages of using this module was its wide range of operating temperature that was between -40 to + 80 C.
The final board was designed to work with 12volt DC and therefore four 3.7V 503562 Lipo batteries with each weighing 23gr were used to supply the board and Peltier modules. Also, and an electronic circuitry was made to control the temperature for every ambient temperature. The design was tested and the result was quite satisfying and submitted to the client for the prototyping.