A signal-level converter is provided between a first terminal and a second
terminal. The first terminal is connected to a first logic circuit
operating at a first supply voltage higher than a given reference
voltage. The second terminal is connected to a second logic circuit
operating at a second supply voltage higher than the first supply
voltage. The signal-level converter has a switching transistor that forms
a current passage between the first and the second terminals in response
to a control signal supplied to a gate of the switching transistor and a
bus-hold circuitry, provided between the switching transistor and either
the first or the second terminal as the output terminal, the other being
the input terminal, and configured to convert a voltage level of a signal
transferred via the switching transistor into another voltage level at
the output terminal. The bus-hold circuitry may have two bus-hold
circuits between the input and the output terminals, for two-way signal
transfer. The bus-hold circuitry may have one bus-hold circuit between
the switching transistor and the output terminal, for one-way signal
transfer. These circuit arrangements offer reduced chip size and
simplified control operations for accurate output-terminal voltages.
Moreover, the arrangements omit one direction-switching terminal in
two-way signal transfer.