Power Optimization Techniques
To achieve significant power optimization, GPSBull employs the following strategies:
- Clock Gating: Reduces power by disabling the clock signal to inactive modules.
- Logic Factorization: Simplifies logic functions to minimize gate usage.
- Don’t Care Optimization: Utilizes don’t care conditions in logic design for efficiency.
- Path Balancing: Ensures equal timing paths to minimize power consumption.
- Technology Mapping: Matches logic functions to the most efficient technology cells.
- State Encoding: Optimizes state representations to reduce transitions and power usage.
- Finite-State Machine Decomposition: Breaks down complex state machines into simpler components for better optimization.
- Retiming: Adjusts the placement of registers to balance delays and reduce power.
Circuit-Level Power Optimization
GPSBull employs various techniques to reduce power consumption at the circuit level, including:
- Transistor Sizing: Adjusts the dimensions of gates or transistors to minimize power usage.
- Voltage Scaling: Uses lower supply voltages to decrease power, albeit with slower performance.
- Voltage Islands: Allows different circuit blocks to operate at varying voltages, saving power while requiring level shifters for communication.
- Variable VDD: Modulates voltage levels in a block during operation, providing high power when needed and low power during slower operations.
- Multiple Threshold Voltages: Utilizes transistors with varying threshold voltages to optimize power; High-Vt transistors reduce leakage in non-critical circuits while Low-Vt transistors enhance speed.
- Power Gating: Incorporates high-Vt sleep transistors to cut off power to inactive circuit blocks, reducing leakage and enabling effective Iddq testing.
- Long-Channel Transistors: Employs longer transistors that, while larger and slower, leak less.
- Stacking and Parking States: Identifies input states that result in lower leakage for logic gates.
- Logic Styles: Chooses between dynamic and static logic based on speed and power trade-offs.
These comprehensive techniques ensure that GPSBull optimizes power consumption effectively across all projects, enhancing overall performance and efficiency.