mcf5272 Freescale Semiconductor, Inc, mcf5272 Datasheet - Page 537

• Manufacturer Part Number: mcf5272
• Description: Mcf5272 Coldfire Integrated Microprocessor User
• Manufacturer: Freescale Semiconductor, Inc

MOTOROLA
Appendix B
Buffering and Impedance Matching
When required:
What to do:
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system configuration.
to ensure setup and hold times are met and to minimize EMC noise in terms of
overshoot and undershoot of signals.
peripherals.
Add buffers on address and control signals shared by SDRAM and other
SDRAM and a large number of external peripherals are required for a particular
Some peripherals may have excessive input capacitance.
Minimize signal reflections at higher clock speeds.
Minimize capacitive loading on signals to SDRAMs.
Operation of MCF5272 at highest frequencies, i.e. 66MHz, requires clean signals
NEVER put buffers between the MCF5272 device and the SDRAMs.
Put termination resistors as close as possible to outputs.
Or use buffers that have integral termination resistors.
Appendix B. Buffering and Impedance Matching
B-1