Abstract: A photodetection device according to the present disclosure includes: a pixel; a reference signal generation unit; a comparison circuit; and a first switch. The pixel is configured to generate a pixel signal. The reference signal generation unit is configured to generate a reference signal. The comparison circuit includes a first-stage amplifier circuit and a second-stage amplifier circuit that is coupled to the first-stage amplifier circuit through a connection node. The first-stage amplifier circuit is configured to output a first output signal corresponding to a comparison operation based on the pixel signal and the reference signal. The second-stage amplifier circuit is configured to output a second output signal corresponding to the first output signal outputted from the first-stage amplifier circuit through the connection node. The first switch has one end and another end. The one end is coupled to the connection node. The first switch allows impedance and a voltage at the connection node to change.

Abstract: An information appliance in which a telephone unit having at least a telephone function and an information processing apparatus having at least a data input/processing function are arranged so as to be capable of being used separably or of being combined with each other through inter connection means provided therebetween, so that the telephone unit and the information processing apparatus are electrically connected to each other when the telephone unit and the information processing apparatus are combined with each other.

Abstract: A data storage apparatus used in a form incorporated into a computer system or the like comprises a storage medium including a multiplicity of usual data regions each of which has a predetermined capacity and in or from which usual data are to be written or read and management data regions which are provided corresponding to the usual data regions or a plurality groups of usual data regions respectively and in which management data from the corresponding usual data regions are to be stored. When the writing or reading of usual data in or from a certain usual data region has resulted in a failure, management data stored in a management data region corresponding to that usual data region are rewritten.