Patent ID: 7394416

Claim:
An analog-digital converter, comprising: an analog switch on a semiconductor substrate, the analog switch having a P-channel transistor and an N-channel transistor; and a capacitive element having a first electrode and a second electrode, wherein a source region of the P-channel transistor is connected to a drain region of the N-channel transistor, a source region of the N-channel transistor is connected to a drain region of the P-channel transistor, and the first electrode of the capacitive element is connected to one of connected portions of the regions, and the first electrode and the second electrode are included in a region in a layer different from a layer of the analog switch, the region extending over the analog switch, and the first electrode and the second electrode have a comb-shaped pattern different from an arrangement pattern of the source regions and the drain regions of the P-channel transistor and the N-channel transistor.