
Switched-Capacitor DC-DC Converters
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impulses. Additionally, the value of R
on
depends on the input signal, thereby
introducing signal-dependent distortions to the converter. In a word, SC DC-DC
converters suffer from current-mode EMI in the form of tones or harmonics.
Moreover, R
on
dissipates energy, hence reducing the achievable conversion effi -
ciency. To minimize the power loss due to R
on
, the MOS transistors, which are used
to implement the switches in an SC DC-DC converter, must be designed to have
large (W/L) ratios, where W is the effective gate width and L is the effective gate
length. This in a sense limits the degree of compactness ...