Digital Design Techniques Top-Down Design vs. Bottom-Up Design
Digital circuits can be designed at Top-Down or from Bottom-Up. In bottom-up design,
the details are figured out first. For example, transistor or mask-level cells are designed
first. Later the individual cells are connected to form the complete design.
In top-down design, the system is designed at an abstract level such as at behavioral or
architectural level first, details are figured out later. For example, the top-level block
diagram with system input and output is designed first. Then RT level description is
written. Gate-Level Description is generated later. Afterwards, it is converted to Mapped
Layout to prepare for FPLD Programming or Mask-Level Layout is generated for
sending design to Fabrication (for fabrication of an ASIC).
Top-Down design takes away from Logic (Gate) and Circuit (Transistor) to abstract
behavior, macro architecture and abstract programming (HDL)
Digital circuits can be designed at Top-Down or from Bottom-Up. In bottom-up design,
the details are figured out first. For example, transistor or mask-level cells are designed
first. Later the individual cells are connected to form the complete design.
In top-down design, the system is designed at an abstract level such as at behavioral or
architectural level first, details are figured out later. For example, the top-level block
diagram with system input and output is designed first. Then RT level description is
written. Gate-Level Description is generated later. Afterwards, it is converted to Mapped
Layout to prepare for FPLD Programming or Mask-Level Layout is generated for
sending design to Fabrication (for fabrication of an ASIC).
Top-Down design takes away from Logic (Gate) and Circuit (Transistor) to abstract
behavior, macro architecture and abstract programming (HDL)
No comments:
Post a Comment