Toggle Gate

The ToggleGate component is intended to help save power by avoiding unnecessary toggles through combinational logic. It accomplishes this by flopping the previous value of data and muxing the previous value to the gatedData output if the enable is low. By default, the flops within the ToggleGate are also clock gated for extra power savings, but it can be controlled via a ClockGateControlInterface.

As an example use case, if you have a large arithmetic unit but only care about the result when a valid bit is high, you could use a ToggleGate so that the inputs to that combinational logic do not change unless valid is high.

final toggleGate = ToggleGate(
  clk: clk,
  reset: reset,
  enable: arithmeticDataValid,
  data: arithmeticData,
);

BigArithmeticUnit(dataIn: toggleGate.gatedData);