Editing Clock signal (section)

== Other circuits ==

Some sensitive [[Mixed-signal integrated circuit|mixed-signal circuits]], such as precision [[analog-to-digital converter]]s, use [[sine wave]]s rather than square waves as their clock signals, because square waves contain high-frequency [[harmonic]]s that can interfere with the analog circuitry and cause [[signal noise|noise]]. Such sine wave clocks are often [[differential signaling|differential signals]], because this type of signal has twice the [[slew rate]], and therefore half the timing uncertainty, of a [[single-ended signalling|single-ended signal]] with the same voltage range. Differential signals radiate less strongly than a single line. Alternatively, a single line shielded by power and ground lines can be used.

In CMOS circuits, gate capacitances are charged and discharged continually. A capacitor does not dissipate energy, but energy is wasted in the driving transistors. In [[reversible computing]], [[inductor]]s can be used to store this energy and reduce the energy loss, but they tend to be quite large. Alternatively, using a sine wave clock, CMOS [[transmission gate]]s and energy-saving techniques, the power requirements can be reduced.{{Citation needed|date=October 2008}}