This paper describes a methodology for passive thermal management of a microelectromechanical system (MEMS) sensor. The MEMS sensor has a temperature rate dependence that must be minimized while the system containing the sensor experiences thermal transients from a cold power-up. A multi-step packaging concept has been developed to manage the thermal transient at the MEMS sensor. The strategy minimizes heat flow to the sensor through use of thin, high thermal resistance kovar leads and an insulating air gap between sensor and electronics. The thermal mass of the sensor assembly is increased with minimal increases in weight and volume by mounting the sensor on a high heat capacity beryllium block. Lastly, a commercial off-the-shelf (COTS) heat sink diverts as much of the heat dissipation into the ambient air as possible. This paper describes the practical implementation of these concepts. This includes the soldering of the leads to the board, the mounting of the component onto the block, and the positioning of the block relative to the frame. This paper also presents a lumped parameter thermal analysis of the packaging. The analysis predicted a maximum dT/dt of 0.4K/minute where dT/dt is the temporal derivative of the MEMS sensor temperature. Test data validating the model is also presented.
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