AN2127 Freescale Semiconductor / Motorola, AN2127 Datasheet
AN2127
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AN2127 Summary of contents
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... BDRV bit in the hard reset configuration word. Many board applications are configured such that This document contains information on a new product. Specifications and information herein are subject to change without notice. © MOTOROLA 2002, All Rights Reserved For More Information On This Product, 4 References Go to: www.freescale.com Order this document by: AN2127/D section. for MPC55x and DDI ...
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Freescale Semiconductor, Inc. this results in the selection of full drive strength. Full drive strength for CLKOUT assumes a load and is intended for test purposes only. Unless full drive strength is required for timing considerations, it ...
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Freescale Semiconductor, Inc. 2.6 Slew Rate Slew rate is controlled by the SLRC[0:3] bits in the PDMCR register. Slow slew rate should be used unless insufficient for system timing requirements. The default configuration is for slow slew rate. Slow slew ...
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Freescale Semiconductor, Inc. Trace Capacitor Incorrect Figure 1 Vias for Decoupling Capacitors The remaining capacitors are required for decoupling the low-voltage (3.3-V or 2.6-V) MCU supply. The MPC55x and the MPC56x have different ball maps. Also, some ...
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Freescale Semiconductor, Inc. Figure 2 MPC55x Double-Sided Component Placement Application 2. MPC55x Single-Sided Component Placement Application In this situation, the capacitors should be placed as close as possible, and on the same side of the PCB, as the MCU. Connect ...
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Freescale Semiconductor, Inc. land). The negative side of the capacitors should be connected with multiple vias to the ground plane (see Figure 3). Figure 3 MPC55x Single-Sided Component Placement Application 3. MPC56x Double-Sided Component Placement Application With this approach, the ...
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Freescale Semiconductor, Inc. balls should NOT be tied directly to the power plane, but instead should route up to the top layer and over to the 10 nF capacitors. After routing to the 10 nF capacitors, a connection to the ...
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Freescale Semiconductor, Inc. vias from VDD balls to top side (not connected to power plane) not shown in side view vias to power plane Figure 4 MPC56x Double-Sided Component Placement Application Example 4. MPC56x Single-Sided Component Placement Application In this ...
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Freescale Semiconductor, Inc. which connect all four V balls to the two capacitors. There should also be wide topside strips con- DD necting all four V balls to the capacitors. After the connected to the power and ...
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Freescale Semiconductor, Inc. via to ground plane via to power plane VDD capacitor VSS not shown in side view Figure 5 MPC56x Single-Sided Component Placement Application 3.2 Standard Grounding Most MCU based systems will partition different classes of circuits with ...
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Freescale Semiconductor, Inc Power Supply Battery Figure 6 Typical MCU Application Grounding Example 3.3 Micro-Island Approach to Decoupling and Grounding The micro-island approach to decoupling and grounding is the premier solution for high-speed digital noise isolation, and as ...
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Freescale Semiconductor, Inc. Micro-Island Signals Leaving Micro-Island Resistors Figure 7 Typical Micro-Island Approach to Decoupling and Grounding 3.4 Signal Routing and Terminations High-speed signals should be isolated as much as possible by using spacing and shielding of the signal traces. ...
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Freescale Semiconductor, Inc. Components The use of many vias for power and ground connections is stressed throughout this document. Howev- er, care must be taken to avoid degradation of the power and ground planes by too many via anti-pads obstructing ...
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Freescale Semiconductor, Inc. Circuit EXTAL XTAL Figure 10 Oscillator CIrcuit and Layout 4 References 4.1 MPC500 Family Reference Documentation 1. MPC555 / MPC556 User’s Manual 2. MPC565 / MPC566 Reference Manual 3. MPC561/MPC563 Reference ...
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Freescale Semiconductor, Inc. 4.3 General EMC References 1. Clayton, Paul. Introduction to Electromagnetic Compatibility 2. Johnson, Howard. High-Speed Digital Design: A Handbook of Black Magic 1993. 3. Ott, Henry. Noise Reduction Techniques in Electronic Systems 4. Kimmel Gerke Associates website, ...
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... For More Information On This Product, JAPAN Motorola Japan Ltd. SPS, Technical Information Center 3-20-1, Minami-Azabu, Minato-ku Tokyo 106-8573 Japan 81-3-3440-3569 ASIA/PACIFIC Motorola Semiconductors H.K. Ltd. Silicon Harbour Centre 2 Dai King Street Tai Po Industrial Estate Tai Po, N.T., Hong Kong 852-26668334 Go to: www.freescale.com Home Page http://www.motorola.com/semiconductors Order Number AN2127/D ...