an approximation thereto), in contrast to more traditional non-adiabatic systems that have generally used constant voltage charging from a fixed-voltage power supply. Power supply The power supplies of adiabatic logic circuits have also used circuit elements capable of storing energy. This is often done using inductors, which store the energy by converting it to magnetic flux. There are a number of synonyms that have been used by other authors to refer to adiabatic logic type systems, these include: "charge recovery logic", "charge recycling logic", "clock-powered logic", "energy recovery logic" and "energy recycling logic". Because of the reversibility requirements for a system to be fully adiabatic, most of these synonyms actually refer to, and can be used inter-changeably, to describe quasi-adiabatic systems. These terms are succinct and self-explanatory, so the only term that warrants further explanation is "clock-powered logic". This has been used because many adiabatic circuits use a combined power supply and clock, or a "power-clock". This a variable, usually multi-phase, power-supply which controls the operation of the logic by supplying energy to it, and subsequently recovering energy from it. Because high-Q inductors are not available in CMOS, inductors must be off-chip, so adiabatic switching with inductors are limited to designs which use only a few inductors. Quasi-adiabatic stepwise charging avoids inductors entirely by storing recovered energy in capacitors. Stepwise charging (SWC) can use on-chip capacitors. Asynchrobatic logic, introduced in 2004, is a CMOS logic family design style using internal stepwise charging that attempts to combine the low-power benefits of the seemingly contradictory ideas of "clock-powered logic" (adiabatic circuits) and "circuits without clocks" (asynchronous circuits). CMOS adiabatic circuits There are some classical approaches to reduce the dynamic power such as reducing supply voltage, decreasing physical capacitance and reducing switching activity. These techniques are not fit enough to meet today's power requirement. However, most research has focused on building adiabatic logic, which is a promising design for low power applications. Adiabatic logic works with the concept of switching activities which reduces the power by giving stored energy back to the supply. Thus, the term adiabatic logic is used in low-power VLSI circuits which implements reversible logic. In this, the main design changes are focused in power clock which plays the vital role in the principle of operation. Each phase of the power clock gives user to achieve the two major design rules for the adiabatic circuit design. Never turn on a