Patent attributes
An oscillation circuit 10 outputs oscillation clocks 100 different in phase, and a four-phase clock generation circuit 20 generates a four-phase clock 200 based on a difference in phase between the oscillation clocks 100. A four-phase clock transfer control circuit 50 controls whether to transfer the four-phase clock 200 in accordance with a signal CP_EN, and a pump circuit 60 generates a boosted voltage based on the transferred four-phase clock. A time period of delay Tos between clocks included in the four-phase clock 200 is generated based on the difference in phase between the oscillation clocks 100, and therefore always in a proportional relationship with a cycle (Tosc) of the oscillation clocks 100. Accordingly, even if the cycle (Tosc) is changed due to operating conditions, and therefore a time period of charge transfer (Ttr) can be uniquely determined.
