Power Planning
Power planning builds the conductive network that delivers stable VDD and VSS from package connections to every standard cell and macro.
The grid must control voltage drop and current density across all operating conditions without blocking excessive signal routing.
A dense compute block may need closer strap pitch than a low-activity control block because its simultaneous switching current is higher.
Physical Design flow
Follow each stage in sequence. Every stage produces information needed by the next.
Power Planning—visualized
This technical view uses the actual structures and relationships associated with this stage, followed by its key terms.
Understand every concept
Rings, straps and rails
What it is: Rings, straps and rails is a core concept within Power Planning. It describes the information, structure, or analysis engineers use at this stage of the Physical Design flow.
Why it matters: Understanding it helps you interpret the stage correctly, avoid incorrect assumptions, and connect the result to the next implementation or signoff step.
Where it fits: This topic belongs to module 3, Power Planning, and its output supports the stages that follow.
Practical example: Engineer workflow: Estimate current demand and identify high-current regions. A dense compute block may need closer strap pitch than a low-activity control block because its simultaneous switching current is higher.
Power connectivity
What it is: Power connectivity is a core concept within Power Planning. It describes the information, structure, or analysis engineers use at this stage of the Physical Design flow.
Why it matters: Understanding it helps you interpret the stage correctly, avoid incorrect assumptions, and connect the result to the next implementation or signoff step.
Where it fits: This topic belongs to module 3, Power Planning, and its output supports the stages that follow.
Practical example: Engineer workflow: Create core rings and macro power connections. A dense compute block may need closer strap pitch than a low-activity control block because its simultaneous switching current is higher.
Early IR-drop thinking
What it is: Early IR-drop thinking is a core concept within Power Planning. It describes the information, structure, or analysis engineers use at this stage of the Physical Design flow.
Why it matters: Understanding it helps you interpret the stage correctly, avoid incorrect assumptions, and connect the result to the next implementation or signoff step.
Where it fits: This topic belongs to module 3, Power Planning, and its output supports the stages that follow.
Practical example: Engineer workflow: Add vertical and horizontal straps across suitable metal layers. A dense compute block may need closer strap pitch than a low-activity control block because its simultaneous switching current is higher.
Work through it step by step
- 1
Rings, straps and rails
Estimate current demand and identify high-current regions.
- 2
Power connectivity
Create core rings and macro power connections.
- 3
Early IR-drop thinking
Add vertical and horizontal straps across suitable metal layers.
- 4
Rings, straps and rails
Connect rails, verify continuity, and run early IR-drop analysis.
Explore each topic
01Rings, straps and rails
Understand the concept, connect it to the ASIC flow, study the report or behavior it produces, and apply it in a guided exercise. Check the result against the module goal before moving forward.
02Power connectivity
Understand the concept, connect it to the ASIC flow, study the report or behavior it produces, and apply it in a guided exercise. Check the result against the module goal before moving forward.
03Early IR-drop thinking
Understand the concept, connect it to the ASIC flow, study the report or behavior it produces, and apply it in a guided exercise. Check the result against the module goal before moving forward.
Completion checklist
- ✓ All power pins connect
- ✓ Strap width and pitch follow rules
- ✓ Early IR drop is acceptable
- ✓ Signal-routing capacity remains sufficient
Practise with open-source tools
These are official third-party GitHub projects selected for this learning path.