Power and Energy Power is drawn from a voltage source attached to the VDD pin(s) of a chip. Instantaneous Power: P (t ) = I (t )V (t ) Energy: Average Power: 7: Power – Half the energy from VDD is dissipated in the pMOS transistor as heat, other half stored in capacitor When the gate output falls – Energy in capacitor is dumped to GND – Dissipated as heat in the nMOS transistor