AN2536 Freescale Semiconductor / Motorola, AN2536 Datasheet
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... Freescale Semiconductor, Inc. Application Note AN2536/D Rev. 0, 07/2003 MC9328MX1/MXL HighSpeed Layout Design Guidelines Contents 1 Introduction 1 Introduction . . . . . . . . . 1 Design of memory systems becomes more complex as the operation frequency increases Design consideration . . 1 2.1 Board material effect . . 1 low power environment. A number of criteria should be considered to achieve maximum 2 ...
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Freescale Semiconductor, Inc. Design Consideration Where Q and Q are charges distance between the charges (m force (N) and dielectric (F/m). Each PCB substrate has a different relative dielectric constant. The dielectric constant ...
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Freescale Semiconductor, Inc. Using the typical values mil mil 1.4 mil, microstrip impedance (Z) yields the results show in Figure 2 through Figure 4. The measurement unit in Equation 3 is ...
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Freescale Semiconductor, Inc. Design Consideration Figure 4. Impedance vs. Trace Thickness (T) Stripline Impedance A circuit trace routed on an inside layer of the PCB with two low-voltage reference planes (i.e., power and / or GND) constitutes a stripline layout. ...
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Freescale Semiconductor, Inc. Figure 6. Stripline Trace Impedance vs. Trace Height (H) Figure 7. Stripline Trace Impedance vs. Trace Thickness (T) In Figure 5 through Figure 7, we found the impedance is inversely proportional to trace width and directly proportional ...
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Freescale Semiconductor, Inc. Design Consideration Figure 8. Propagation Delay vs. Dielectric Constant For Microstrip and Stripline Traces. As 2.2 On-Board Noise Source Crosstalk Crosstalk is the unwanted coupling of signals between parallel traces. Proper routing and layer stack-up through microstrip ...
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Freescale Semiconductor, Inc. • Place a ground plane next to the outer layer to minimize noise. If you use an inner layer to route the clock trace, sandwich the layer between reference planes. • Terminate clock signals to minimize reflection. ...
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Freescale Semiconductor, Inc. Design Consideration noise is filtered by a large 10-uF capacitor after the ferrite bead. Usually, elements on the PCB add high- frequency noise to the power plane. To filter the high-frequency noise at the device, place decoupling ...
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Freescale Semiconductor, Inc. • Use ferrite beads to isolate the PLL power supply from digital power supply. Ground Bounce As digital devices become faster, their output switching times decrease. Faster switching times cause higher transient currents in outputs as they ...
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Freescale Semiconductor, Inc. Design Consideration • Eliminate pull-up resistors or use pull-down resistors. • Use multi-layer PCBs that provide separate VCC and ground planes to utilize the intrinsic capacitance of GND-VCC plane. • Add ohm resistors in ...
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Freescale Semiconductor, Inc. of the bounce can be large enough to trigger other devices on the PCB. In synchronous designs, ground bounce is less often a problem because synchronous outputs have enough time to settle before the next clock edge. ...
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Freescale Semiconductor, Inc. Design Consideration Figure 16. Thevenin Parallel Termination Active Parallel Termination—An active parallel termination scheme, the terminating resistor (R tied to a bias voltage ( this scheme, the voltage is selected so that the output drivers ...
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Freescale Semiconductor, Inc. constant. Therefore, for high-speed designs, you should perform the pre-layout signal integrity simulation with silicon input/output buffer information specification (IBIS) models before using the series termination scheme. 3 MC9328MX1/MXL Case Study The critical high speed signals are ...
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Freescale Semiconductor, Inc. MC9328MX1/MXL Case Study Figure 21. Recommend Layout of Memory Devices Following is the requirement list we applied to this development board: • Place the 32 kHz and 16 Mhz crystals close to the core and use short ...
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Freescale Semiconductor, Inc. NET = A2 (The whole trace incl. the route to Socket) COUNTS ------------------------------------------------------------ segments ........... 34 IC drivers ......... 0 IC receivers ....... 7 resistors .......... 0 capacitors ......... 0 INTERCONNECT STATISTICS ------------------------------------ ------- total metal delay ...
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Freescale Semiconductor, Inc. MC9328MX1/MXL Case Study capacitance no larger than 20pF. With ADS ver 1.1, a standard memory test program is executed (refer to Section 5, “References,” on page 22). It shows smooth execution MHz with a ...
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Freescale Semiconductor, Inc. Layer Signals Signal Power Signal Signal Signal Signal GND Signal Figure 25. MC9328MX1 Demo v0.1 PCB Layer Description Cap. 6pF 4pF Loading Data Address Signals pin Figure 26. MC9328MX1 Demo v0.1 Device Capacitive Loading Figure 27. MC9328MX1 ...
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Freescale Semiconductor, Inc. MC9328MX1/MXL Case Study NET = SDCLK INTERCONNECT STATISTICS ------------------------------------------- total metal delay............ 290.740 ps minimum metal Z0 ............. 52.5 ohms maximum metal Z0 ............. 62.5 ohms total metal capacitance ...... 4.7 pF (SDCLK .................................... 4.7 pF) total ...
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Freescale Semiconductor, Inc. The PCB design were: • 8-layer (refer to Figure 25 on page 17) ε • for FR-4 is 4.1 r • Copper Trace width = 6 mil (rings are not added in the inter-layer of the vias) ...
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Freescale Semiconductor, Inc. Design Guidelines on PCB • Configure unused I/O pins as output pins, and drive the output low to reduce ground bounce. This configuration will act as a virtual ground. • Configure the unused I/O pins as output, ...
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Freescale Semiconductor, Inc. • Use multi-layer PCBs that provide separate VCC and ground planes. • Add ohm resistors in series to each of the switching outputs to limit the current flow into each of the outputs. • ...
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Freescale Semiconductor, Inc. References 5 References 1. Johnson, H.W., and & Graham, M., “High-Speed Digital Design.” Prentice Hall, 1993. 2. Hall, S. H., Hall, G. W., and McCall J. A., “High-Speed Digital System Design.” John Wiley & Sons, Inc. 2000 ...
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Freescale Semiconductor, Inc. NMOS Fastest Slowest Figure 29. Process Corner Illustration MOTOROLA MC9328MX1/MXL Application Note For More Information On This Product, NOTES PMOS Slowest Fastest Go to: www.freescale.com 23 ...
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... Motorola and the Stylized M Logo are registered in the U.S. Patent and Trademark Office. All other product or service names are the property of their respective owners. Motorola, Inc Equal Opportunity/Affirmative Action Employer. © Motorola, Inc. 2003 AN2536/D For More Information On This Product, Go to: www.freescale.com ...