Abstract: A current-path isolating circuit is provided in a row decoder circuit that selects a part of the plurality of row lines of a memory array and that selectively provides a selected row line with a voltage level different from that for other row lines. In a test mode different from a normal operation mode, the current-path isolating circuit isolates a current path in the device into a first current path for a current flowing through the row line selected and a second current path for a current not flowing through the row line but flowing through the row decoder circuit. The current path isolated is formed to supply a testing voltage to the selected row line from a testing voltage source.

Abstract: A current-path isolating circuit is provided in a row decoder circuit that selects a part of the plurality of row lines of a memory array and that selectively provides a selected row line with a voltage level different from that for other row lines. In a test mode different form a normal operation mode, the current-path isolating circuit isolates a current path in the device into a first current path for a current flowing through the row line selected and a second current path for a current not flowing through the row line but flowing through the row decoder circuit. The current path isolated is formed to supply a testing voltage to the selected row line from a testing voltage source. By way of external connecting pads each for receiving the testing voltage supplied from the testing voltage source, two pads are provided, wherein one of the two pads corresponds to the first current path and the other one of the two pads corresponds to the second current path.