On-chip temperature control circuit using common devices

Methods and apparatus for extending the effective thermal operating range of a memory

Abstract: Systems, methods, and apparatus are provided for thermal regulation of a non-volatile memory IC. The systems and apparatus may include a thermal sensor on a memory IC; and a heating element coupled to the thermal sensor and adapted to heat the memory IC in response to a signal from the thermal sensor. The methods may include sensing a temperature of a memory IC using an integrated thermal sensor on the memory IC and heating the memory IC, using an integrated heating element operatively coupled to the thermal sensor, if the sensed temperature is below a threshold temperature.

Application of phase change materials for passive thermal control of plastic quad flat packages (PQFP): a computational study

Abstract: A transient three-dimensional analysis was performed for passive thermal control of a plastic quad flat package (PQFP) by incorporating phase change material (PCM) under the printed wiring board (PWB). Governing conservation equations for mass, momentum and energy were solved by an implicit finite volume numerical technique. The effects of phase change were modelled by a single domain enthalpy-porosity technique. To study the effects of thermal conductivity of the board, a total of four cases were considered with two different board materials. It was found that passive cooling with PCM can arrest the temperature rise for a substantial time, for the power level considered. A higher board thermal conductivity resulted in a reduction in temperature levels. The melt region for a lower thermal conductivity of the board was found to be localized near the package footprint, while, for a higher board conductivity, the melt region extends along the board.

Static and dynamic thermal behavior of IGBT power modules

Abstract: The trend in power electronics continues towards greater packaging density, speed and high power dissipation. This technology trend resulted in increased operating temperatures, which have in turn lead to an increase 01' the failure rate aud a reduction 01' the reliability, Thus, thermal simulations are playing an essential role in the design 01' high power systems such as vehicles, ships, space crafts, etc, In this thesis, thermal analysis for a 1200A, 3300V IGBT module has been announced at two levels such as a module and a system level. For the module level analysis, the thermal behavior 01' the IGBT module was investigated and analyzed through 3-Dimensional Finite Element Methoel (3D-FEM), SOLIDIS-1SE ancl ANSYS 5.4 in the static and dynamic conditions. For the system level analysis, the total system that consists 01' the IGBT module and a water-cooled heat sink is analyzed in two stages because 01' limited computer rnemory and long solution times. First, by using a Computational Fluid Dynamics (CFD) simulator 1.0 predict the water flow features, the heat sink is modeled. Next, the results 01' the heat sink was applied 1.0 the heat coneluction simulator as boundary conditions. The numerical results 01' the total system are accurate. '1'0 verify the simulation results, measurernent system coupled with infrared system and electrical method has been constructed. Static and dynamic thermal characteristics are measurecl uncler the cyclic self heating conditions. These measurements are cornpared with the simulation results 01' the IGBT module and the total system.

P.m.t.

Abstract: SE HA DESARROLLADO UN NUEVO ENTORNO DE MODELADO ORIENTADO A LA INDUSTRIA DE PROCESOS, EL CUAL GENERA EL MODELO DE SIMULACION DE UNA PLANTA, DESCRITA GRAFICAMENTE A PARTIR DE LA REUTILIZACION DE LOS MODELOS DEFINIDOS "A PRIORI" QUE DEFINEN MODULARMENTE LA DINAMICA DE LOS ELEMENTOS QUE INTEGRAN EL SISTEMA A MODELAR, EL TRABAJO APORTA UNA NUEVA METODOLOGIA PARA ANALIZAR Y MODELAR AUTOMATICAMENTE LAS DINAMICAS EXTERNAS QUE APARECEN COMO FRUTO DE LA INTERACCION ENTRE LOS SUBPROCESOS. LAS HERRAMIENTAS DE MODELADO IMPLEMENTADAS PERMITEN: A) LA "REPRESENTACION DEL CONOCIMIENTO" QUE EL EXPERTO TIENE SOBRE LA DINAMICA DEL SUBPROCESO FISICO A DIFERENTES NIVELES DE ABSTRACCION. B) PROCESAR DICHA INFORMACION EN FUNCION DE LAS CONDICIONES DE OPERACION DONDE SE DESEA REUTILIZAR EL MODELADO.

The Application of Thermoelectric Spot Cooling to Electronic Equipment

Abstract: Summary Recent developments in the construction of thermoelectric coolers have resulted in improved coolers suitable for use in electronic equipment. The continual effort to improve the techniques of cooling electronic equipment led to the investigation of thermoelectric spot cooling of temperature-limiting component parts located within local areas of an electronic equipment. The investigation consisted of the evaluation and application of nine spot coolers constructed to specifications determined by an analysis. Thermal evaluation of the nine spot coolers showed that each spot cooler either met or exceeded the design requirement of pumping 5 w over a 30°C temperature difference. The coefficient of performance exceeded 0.5 for each of the spot coolers operated under the design condition. In addition to the satisfactory thermal performance, a spot cooler passed the mechanical shock and vibration requirements for satellite equipments used in Project Mercury. The information on spot cooler thermal performance was employed in an analytical application of spot cooling to a free-convection and radiation-cooled equipment and a forced-convection-cooled equipment. The results indicate that free-convection - and radiationcooled equipment can be operated in higher temperature environments with spot cooling; moreover, the cooling requirements for forced-convection-cooled equipment can be reduced.