| 摘要 |
PURPOSE: An output interface circuit is provided, which is capable of achieving a fast and stable interface operation even when an external power supply voltage changes from, e.g. 5 V to 3.3 V or 2 V, without the need for extending the size of a chip. CONSTITUTION: A 5 V group output buffer circuit(3) receives an output signal(S1) from an internal circuit(1) and outputs an output signal(S3) to an external output terminal(6) in response to a control signal(S7a) that denotes an external power supply voltage VEXT is higher than a prescribed value. A 3.3 V group output buffer circuit(4) receives the output signal(S1) and outputs an output signal(S4) in response to a control signal(S7b) that denotes the external power supply voltage VEXT is equal to or lower than the prescribed value. An output level adjustment circuit(5) outputs an output signal(S5) resulting from adjusting the level of the output signal(S4) to the external output terminal(6).
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