Design constraints
High-level (or low-level) system requirements get translated into specific design constraints for the integrated circuit
Primary factors are:
- Speed
- To meet a standard - e.g. 66MHz.
- To meet an internal system requirement - e.g. internal system bus speed of 200MHz.
- To meet a specific market requirement - e.g. 800MHz.
- Power
- To meet a system power dissipation limit - no fans!
- To meet a chip cost limit - plastic package (1Watt)
- To differentiate the product (higher MIPS/Watt)
- Chip area
- directly related to chip cost
- Reliability
- System constraints such as 1/10,000 defective boards get translated into IC constraints such as 1 defective part per million (1 DPM)
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Failure to meet any one of these can lead to a failed IC project