M. Cazzaniga, Patrice Joubert Doriol, Emmanuel Blanc, V. Liberali, D. Pandini
{"title":"Evaluating the impact of substrate on power integrity in industrial microcontrollers","authors":"M. Cazzaniga, Patrice Joubert Doriol, Emmanuel Blanc, V. Liberali, D. Pandini","doi":"10.1109/PATMOS.2013.6662162","DOIUrl":"https://doi.org/10.1109/PATMOS.2013.6662162","url":null,"abstract":"The combination of increasing working frequencies and shrinking transistor size following the Moore's Law, dictate the design and fabrication of complex System-on-Chip (SoC) designs, where the digital processing core, SRAMs and embedded flash memories, analog IPs and I/O cells, are integrated onto the same die. Therefore, noise integrity has become a critical concern for high-speed SoC designers, and requires a holistic approach encompassing power and signal integrity along with electromagnetic interference. Although it is a common design practice that the digital core, the analog circuitry, and the I/O cells have separated power distribution networks, the noise injected from the digital core to other SoC regions may propagate through the common silicon substrate. Another important, yet often overlooked, impact of substrate is on power integrity (i.e., static and dynamic IR-drop on both power and ground distribution networks). In fact, in a standard digital design flow, power integrity analysis is usually performed without considering the common substrate network, thus leading to a pessimistic IR-drop estimation that often requires unnecessary routing resources and extra buffering. In this work we present the results for static and dynamic IR-drop analysis on an industrial microcontroller, taking into account the substrate contribution. We show a reduction of the static IR-drop ascribed to the substrate resistivity. Similarly, we demonstrate that the substrate also reduces the dynamic IR-drop because of the increased decoupling capacitance due to the well parasitic junction capacitances. Finally, we highlight the possibility to trade off extrinsic on-chip decoupling capacitances with the well junction capacitances.","PeriodicalId":287176,"journal":{"name":"2013 23rd International Workshop on Power and Timing Modeling, Optimization and Simulation (PATMOS)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125491454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design methodology for low-power embedded microprocessors","authors":"A. Manuzzato, F. Campi, V. Liberali, D. Pandini","doi":"10.1109/patmos.2013.6662187","DOIUrl":"https://doi.org/10.1109/patmos.2013.6662187","url":null,"abstract":"Power constraints are becoming a strong limiting factor in IC design. Lowering supply voltage is an appealing option to control power dissipation, but voltage scaling has a strong impact on performances. It is possible to design specific circuits for near- or even sub-threshold supply voltage, but many design environments cannot afford the development costs for libraries specifically designed and optimized for a sub-threshold regime. This work explores flow and design options for low-voltage targeting a standard library. After extending the library characterization to cover a low-voltage range, synthesis exploration has been performed on reference designs to assess the energy efficiency for different operating voltages/frequencies. The resulting netlists have been analyzed in terms of power dissipation and area after placement and routing. Results for two test cases show the available energy efficiency gain as well as the frequency range for which each reference supply voltage offers a convenient performance, and the design options impacting this choice. The energy efficiency obtained for two operating voltage configurations are compared against the reference designs, showing the different power/performance trade-offs achievable by scaling the supply voltage.","PeriodicalId":287176,"journal":{"name":"2013 23rd International Workshop on Power and Timing Modeling, Optimization and Simulation (PATMOS)","volume":"7 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134379881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}