Search Results

The electronic content in automotive has increased over recent years and expected to contribute about 50% of the total vehicle cost by 2030. The semiconductor research indicates that focus is on enhancing the functionality of single device and miniaturizing of components to reduce the electronic module size. It is to be ensured, that devices in automotive electronic modules should be within its allowable temperature limit while operating at harsh environment. The accurate virtual simulations using CAE tools prior to proto build can assist in understanding the design risks upfront and aids in arriving at a reliable thermal mitigation solution. The prediction accuracy of thermal simulation is driven by the inputs and modeling approach used in the analysis. Current automotive electronic product development trend indicates, chip development and thermal design of electronics module goes in parallel.

Advanced Driver Assistance Systems (ADAS) rely on camera sensors to work effectively to provide warning signs to prevent forward and rearward collision, lane departure, pedestrian detection, traffic sign recognition, automatic headlight control and assists for autonomous driving. Generally, vision based ADAS systems have wide angle cameras installed on front, rear and sides of the vehicle. These camera-based vision sensors are subjected to severe thermal environments that can impact its sensing performance and image quality. Hence it is imperative to thermally qualify the camera module to ensure reliable performance without loss in functionality. The thermal environment experienced by these cameras vary based on their mounting location. Intelligent forward view cameras are mounted in windshield region of the vehicle and encounter sun load in order of 1000 W/m2.

Current generation automobiles are controlled by electronic modules for performing various functions. These electronic modules have numerous semiconductor devices mounted on printed circuit boards. Solders are generally used as thermal interface material between surface mount devices and printed circuit boards (PCB) for efficient heat transfer. In the manufacturing stage, voids are formed in solders during reflow process due to outgassing phenomenon. The presence of these voids in solder for power packages with exposed pads impedes heat flow and can increase the device temperature. Therefore it is imperative to understand the effect of solder voids on thermal characteristics of semiconductor devices. But the solder void pattern will vary drastically during mass manufacturing. Replicating the exact solder void pattern and doing detail simulation to predict the device temperature for each manufactured module is not practical.

Automotive Electronic Control Unit (ECU) has semiconductor devices performing various time dependent functions. It is essential to understand the transient thermal behavior of these devices for designing a reliable system. Detailed thermal model (DTM) is the need of the hour to understand the characteristics by performing a transient system level simulation. The information to build DTM is not readily available in the public domain due to intellectual property protection from the device suppliers. To overcome this, the present work showcases the procedure to develop Transient Thermal Network Model (TTNM) using resistance and capacitance values extracted from the impedance curve provided by the semiconductor manufacturer. TTNM model is developed for a typical DPAK and D2PAK device and validated by comparing impedance curve derived from simulation with datasheet.

In hybrid electric vehicles (HEVs) and full electric vehicles (EVs), efficient electrical power management with proper supply of power at the required voltage levels is essential. A DC (Direct Current)-DC converter is one of the key electrical units in a HEV/EV. The DC-DC converter dealt in the present work is intended to create the DC voltages necessary to power the accessories. The electronic circuit in this DC-DC converter consists of high power devices like Metal-Oxide Semiconductor Field-Effect Transistors (MOSFETs), inductors, transformers, etc. mounted on a printed circuit board (PCB). The DC-DC converter interacts with a high voltage battery pack and supplies a low voltage power to the accessory battery. Due to this power handling operation, the devices in the convertor experience high temperatures. The temperature rise of the devices beyond the permissible limits could be detrimental to an efficient and safe operation of the converter.