PURPOSE: To reduce a chip occupied area by a series resistance circuit and a circuit including it by using a 2nd selection means to apply selectively plural reference voltage sources whose voltage level differs from each other to the series resistance circuit.

CONSTITUTION: The voltage division circuit is provided with switches S11, S12 being a 2nd selection means to apply reference voltages Va, Vb whose voltage levels differ from each other selectively to a series resistance circuit 106 in addition to switches S13, S14 being a 1st selection means to select a voltage level fed to a voltage comparator circuit 101 by selectively coupling plural resistance series connection nodes of the series resistance circuit 106 to the voltage comparator circuit 101. Then desired A/D conversion is attained by controlling the switches S11-S14 with a switch controller 105. Furthermore, in this case components of the circuit 106 are only resistors R11, R12, which results in having the number of components of a conventional circuit. Then the occupied area of the circuit 106 in the chip is reduced by reducing the number of resistive elements in this way.