What is a Domain ? Why do we need them in the design ?

[pavanks]

Why do we create a domain in the design ? I meant the primary domain ?
Is it used only for def the power information ?

 

[ljxpjpjljx]

this is very useful for low power design and verification, we often use CPF or UPF to log the power domain information!

 

[phoenixpavan]

Hi Pavan,

As Jamie pointed out...power domains are created when you want to have a design where different blocks work with different voltage levels. This is a low power design techniques besides methods such as clock gating..

UPF is a unified power format through which you specify the information...

cheers,

 

[logiclife]

In my thought of writing upf/cpf commands is like (just imagine) genertating power supply to a town
the main design is like town
set_scope town :inupf
each sub_domain is like a house,hospital,factory etc
create_power_domain hospital -domain {hospital} :in upf
creating power supply ports is like placing transformer

creating power nets is like alloting current cables around the town

connecting power nets is like connecting cables to your home pins
creating ground nets is like alloting ground to your home

level shifter are like step up or step down transformers between areas

isolation cells are like giving power to operation theatre in a hospital in town irrespective of power supply ICU's in hospital should always switch on the power.