| 摘要 |
PROBLEM TO BE SOLVED: To provide an output circuit, capable of reading/writing data in a semiconductor memory device or the like at high speed and markedly reducing current consumption by preventing through current. SOLUTION: A first level shift circuit 4 is connected to the gate of a pull-up side transistor 2 and converts the voltage of a data signal from an internal power supply potential lower than an external power supply potential to the external power supply potential. A second level shift circuit 5 is connected to the gate of a pull-down side transistor and converts the voltage of the data signal from the internal power supply potential to the external power supply potential. When a change in the data signal read from a memory cell is detected, a control signal is outputted to the first and second level shift circuits. In the first state of the control signal, any one of pull-up side and pull-down side transistors is turned off, and the output terminal is turned into high impedance. In the second state of the control signal, a signal corresponding to high or low of the data signal is outputted to the output terminal.
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