Patent ID: 7215158
Filing Date: 2007-05-08
Classification: H03K

Abstract:
1. A comparator switching apparatus for a plurality of comparators that have respective operation characteristics different from one another in respect of a plurality of operation modes and attain respective comparison operations on a same input signal, the comparator switching apparatus comprising: an operation switching circuit for selectively switching one of the comparators to an operative state in response to a change in a mode switching signal applied from an external side, the one of the comparators being corresponding to a selected operation mode; and a multiplexer for selecting an output signal of the one of the comparators in correspondence to the change in the mode switching signal, wherein the operation switching circuit includes a delay means for delaying the mode switching signal, logic-combines the mode switching signal and a delayed mode switching signal to a logic signal, and switches over the comparators, by using the logic signal, within a period in which at least one of the comparators is in the operative state, and wherein the multiplexer is driven to change a selection operation thereof in response to the delayed mode switching signal.