| 摘要 |
<P>PROBLEM TO BE SOLVED: To cancel a DC offset of an AD conversion device including single-ended-to-differential conversion without requiring two reference analog signals. <P>SOLUTION: According to an embodiment, an AD conversion device includes: a first terminal for receiving reference voltage signals; a single-ended-to-differential conversion circuit for performing single-ended-to-differential conversion on the reference voltage signals to produce first differential signals; an AD converter for performing AD conversion on the first differential signals on the basis of the reference voltage signals to produce a first digital signal; a digital circuit for detecting a DC offset that is a difference between the first digital signal and a digital signal representing a predetermined code; and a second terminal for receiving input signals. The single-ended-to-differential conversion circuit performs single-ended-to-differential conversion on the input signals to acquire second differential signals, the AD converter performs AD conversion on the second differential signals on the basis of the reference voltage signals to acquire a second digital signal, and the digital circuit subtracts the DC offset from the second digital signal to produce a third digital signal and outputs the third digital signal. <P>COPYRIGHT: (C)2013,JPO&INPIT |
