A data storage apparatus includes a data storage unit to store data, a
plurality of buffer units to output data to the data storage unit through
a bus that includes a plurality of signal lines, the plurality of buffer
units being provided on the plurality of signal lines, a determination
unit to determine whether the bus is in an operating state in which
transmission and reception of data to and from the data storage unit are
performed, a reference voltage supply unit to supply a predetermined
reference voltage to the plurality of signal lines, a control unit to
control, in a case where the determination unit determines that a state
of the bus is changed from an operating state to a nonoperating state,
the plurality of buffer units to switch output states to predetermined
output states to reduce an amount of electric current flowing in the bus.