Defining Power Intent with IEEE 1801 UPF

Power intent definition is a core part of modern low-power digital design. IEEE 1801 UPF provides a standardized specification method for describing supply connectivity, power domains, power switching behavior, retention requirements, isolation rules, and simulator semantics without hardcoding those assumptions into RTL. This separation keeps functional logic clean while giving verification and implementation tools a precise model of how the design behaves across different power modes. The technical flow starts from the supply interface. Supply ports define where power and ground enter the design hierarchy, while supply nets describe how those resources are distributed internally. Explicit supply net connections remove ambiguity between external power sources and internal power structures. Supply sets then group related power and ground nets into reusable supply contexts, making it possible to define valid power states and reason consistently about domain activity. Power domains organize the design into regions that share the same power behavior. Each domain can be associated with specific supply sets, controlled independently, and analyzed under different operating states. Switchable domains are modeled with power switches, which define how a control signal enables or disables a supply path. This is essential for representing power gating accurately and for checking whether power-up and power-down sequencing is valid. Retention and isolation strategies address the two most critical risks in power-gated systems: state loss and invalid signal propagation. Retention rules specify which sequential elements preserve state during shutdown, what retention supply is used, and which save and restore controls manage retained data. Isolation rules specify where signal clamping is needed, which control signal enables isolation, and what value is driven when the source domain is inactive. These strategies allow selected logic to power down while active regions remain functionally safe. Power-aware simulation controls complete the UPF definition by specifying how simulation should handle power events, initialization replay, and corruption of variables under invalid supply conditions. These controls help expose design defects that ordinary RTL simulation cannot detect. A structured UPF definition improves consistency across simulation, verification, synthesis, implementation, and signoff, especially in designs with multiple power domains, always-on logic, retained state, and complex low-power operating modes. Catalogue: Power Intent Definition Flow Step1: Create supply ports (I) Step1: Create supply ports (II) Step1: Create supply ports (III) Step2: Create supply nets (I) Step2: Create supply nets (II) Step3: Connect supply nets (I) Step3: Connect supply nets (II) Step3: Connect supply nets (III) Step4: Create supply sets (I) Step4: Create supply sets (II) Step4: Create supply sets (III) Step5: Create power domains (I) Step5: Create power domains (II) Step5: Create power domains (III) Step6: Create power switches (I) Step6: Create power switches (II) Step6: Create power switches (III) Step7: Set retention strategies (I) Step7: Set retention strategies (II) Step7: Set retention strategies (III) Step7: Set retention strategies (IV) Step7: Set retention strategies (V) Step8: Set isolation strategies (I) Step8: Set isolation strategies (II) Step8: Set isolation strategies (III) Step8: Set isolation strategies (IV) Step8: Set isolation strategies (V) Step8: Set isolation strategies (VI) Step9: Set simulator controls (I) Step9: Set simulator controls (II)