digital electronics Digital electronics is a field of electronics involving the study of digital signals and the engineering of devices that use or produce them. It deals with the relationship between Binary number, binary inputs and outputs by passing electrical s ...

, the power–delay product (PDP) is a figure of merit correlated with the energy efficiency of a

logic gate A logic gate is a device that performs a Boolean function, a logical operation performed on one or more binary inputs that produces a single binary output. Depending on the context, the term may refer to an ideal logic gate, one that has, for ...

logic family In computer engineering, a logic family is one of two related concepts: * A logic family of monolithic digital integrated circuit devices is a group of electronic logic gates constructed using one of several different designs, usually with compati ...

. Also known as switching energy, it is the product of

power consumption Electric energy consumption is energy consumption in the form of electrical energy. About a fifth of global energy is consumed as electricity: for residential, industrial, commercial, transportation and other purposes. The global electricity con ...

''P'' (averaged over a switching event) times the input–output delay or duration of the switching event ''D''. It has the dimension of energy and measures the energy consumed per switching event. In a

CMOS Complementary metal–oxide–semiconductor (CMOS, pronounced "sea-moss ", , ) is a type of MOSFET, metal–oxide–semiconductor field-effect transistor (MOSFET) semiconductor device fabrication, fabrication process that uses complementary an ...

circuit the switching energy and thus the PDP for a 0-to-1-to-0 computation cycle is C_L·V_DD². Therefore, lowering the supply voltage V_DD lowers the PDP. Energy-efficient circuits with a low PDP may also be performing very slowly, thus energy–delay product (EDP), the product of ''E'' and ''D'' (or ''P'' and ''D''²), is sometimes a preferable metric. In CMOS circuits the delay is inversely proportional to the supply voltage V_DD and hence EDP is proportional to V_DD. Consequently, lowering V_DD also benefits EDP.

See also

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Further reading