AN2586 Freescale Semiconductor / Motorola, AN2586 Datasheet
AN2586
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AN2586 Summary of contents
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... Freescale Semiconductor, Inc. Application Note AN2586 Rev. 0, 1/2004 MPC8260 PowerQUICC II Family Power Distribution Trends: A Survey NCSD Applications This application note presents a survey of power distribution circuits that are needed to deliver Austin, Texas sufficient quiet supply to the MPC8260 PowerQUICC II™ family of integrated communications processors, and highlights issues that arise with systems that are based on a high performance processor such as the MPC8260 ...
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Freescale Semiconductor, Inc. Introduction Introduction 1 Introduction One important step for designing a high speed digital system is to pre-plan for the power distribution strategy. The strategy should cover the following aspects: • Power supply circuit design • Power supply ...
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Freescale Semiconductor, Inc. • Bypass capacitors connection to load Also from the perspective of the power delivery network, answers to the following are not known: • What is the optimal topology of the supply and ground layers, given a set ...
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Freescale Semiconductor, Inc. Previous Work Study Previous Work Study • How do we incorporate EMI reduction to our effort this, we need to summarize what others have done so far. 3.1 How to estimate bypass capacitors? Different systems ...
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Freescale Semiconductor, Inc. This excessive amount of current change definitely creates a huge stress on the power delivery network, especially if it was not properly designed. So far we have seen some description of load current consumption and have had ...
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Freescale Semiconductor, Inc. Previous Work Study Previous Work Study The Xmax that is maximum common path impedance we can tolerate at the consumed current is the following: As shown in the following equation, Fpsw is the frequency below which the ...
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Freescale Semiconductor, Inc use a standard SMT capacitor, the series L is around 2nH, which means we need m as follows: This result tells us that we need at least eight capacitors to maintain an adequate bypass till ...
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Freescale Semiconductor, Inc. Previous Work Study Previous Work Study Using a Intusoft simulator, the following (Figure 5) is the voltage measurement as we sweep the AC current source frequency. Note that the AC amplitude is 1Amp, which makes the curve ...
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Freescale Semiconductor, Inc. MOTOROLA MPC8260 PowerQUICC II Family Power Distribution Trends: A Survey For More Information On This Product, Figure 6. Go to: www.freescale.com Previous Work Study 9 ...
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Freescale Semiconductor, Inc. Previous Work Study Previous Work Study To increase the accuracy of the circuit model, include the effective series resistance of each capacitor as well as including some wiring resistance, which acts as a damping factor. We expect ...
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Freescale Semiconductor, Inc. Figure 8 shows the same circuit model that we have so far, but with additional damping resistors that are inherent in each bypass capacitor as well as the power supply delivery network. The step response will resemble ...
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Freescale Semiconductor, Inc. Previous Work Study Previous Work Study Also, the AC response to the 1 Amps sweeping AC at the current source of the load will resemble Figure 9. Note how the damping resistance changed the AC response. 3.1.1 ...
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Freescale Semiconductor, Inc. • Is there any coupling between different power pins? • Is there any coupling inside the die itself between different power blocks? • What is the block power demand circuit model? As mentioned earlier, the scope of ...
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Freescale Semiconductor, Inc. Previous Work Study Previous Work Study Dark blue circles are the ground for I/O and Core. Red circles are the Core power input. Yellow circles are the I/O power input. Green circles are the PLL power input. ...
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... These equations are made discrete in both time and space, with an accuracy level that is consequently lost. When the tools have the discrete equation that can be represented in a matrix format, the tools attempt to solve these matrices given an input and a desired output. Many results can be obtained and used to study the behavior of the design as well the ‘ ...
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Freescale Semiconductor, Inc. Previous Work Study Previous Work Study 3.4 What can be done with the PDN model? When a circuit model is extracted from the layout, the design engineer can do the circuit analysis needed to proof that the ...
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Freescale Semiconductor, Inc. Placing a decoupling capacitor on the power distribution network changes the overall impedance profile of it. When we identify the main peaks of the PDN impedance, we try to add bypass capacitors that are capable of suppressing ...
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Freescale Semiconductor, Inc. References References 7. Shiyou Zhao; Roy, K.; Cheng-Kok Koh.Decoupling capacitance allocation and its application to power-supply noise-aware floor planning. Computer-Aided Design of Integrated Circuits and Systems, IEEE Transactions on , Volume: 21 Issue Jan. 2002 ...
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Freescale Semiconductor, Inc. THIS PAGE INTENTIONALLY LEFT BLANK MOTOROLA MPC8260 PowerQUICC II Family Power Distribution Trends: A Survey For More Information On This Product, Go to: www.freescale.com References 19 ...
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... The PowerPC name is a trademark of IBM Corp. and used under license. All other product or service names are the property of their respective owners. Motorola, Inc Equal Opportunity/Affirmative Action Employer. © Motorola, Inc. 2004 AN2586 For More Information On This Product, Go to: www.freescale.com ...