455 results about "Power gating" patented technology

Field Programmable Logic Arrays (FPGAs) are described which utilize multiple power supply voltages to reduce both dynamic power and leakage power without sacrificing speed or substantially increasing device area. Power reduction mechanisms are described for numerous portions of the FPGA, including logic blocks, routing circuits, connection blocks, switch blocks, configuration memory cells, and so forth. Embodiments describe circuits and methods for implementing multiple supplies as sources of Vdd, multiple voltage thresholding Vt, signal level translators, and power gating of circuitry to deactivate portions of the circuit which are inactive. The supply voltage levels can be fixed, or programmable. Methods are described for performing circuit CAD in the routing and assignment process on FPGAs, in particular for optimizing FPGA use having the power reduction circuits taught. Routing methods describe utilizing slack timing, power sensitivity, trace-based simulations, and other techniques to optimize circuit utilization on a multi Vdd FPGA.

A method of power gating a latch including detecting a state of the latch, detecting a power gate signal, providing power to the latch while the power gate signal is negated, and removing power from the latch when the power gate signal is asserted and the latch is in a predetermined state. The method may include any one or more of pulling a node of the latch to a selected state while the power gate signal is asserted to ensure that the latch powers up in the predetermined state, providing a signal indicative of the latch state and the power gate signal to respective inputs of a logic gate having an output indicative thereof, switching a supply voltage to a power input of the latch based on a state of the output of the logic gate, and closing a switch to pull a node of the latch low.

A method and a structure provide a space efficient integrated circuit using standard cells and power gating by switch cells. The standard cells may be tapless, i.e., not provided a substrate connection to a power supply or ground rail by a tap within the cell. The substrate connection for these standard cells may be provided by the switch cells or by specialized tap cells. The tapless standard cells may include only a context-sensitive rail, which may be configured to be a virtual ground rail by a power gating connection to a switch cell or by a direct connection to a power supply or ground rail.