INTERFACE CIRCUIT

摘要

According to one embodiment, a first pull-down transistor, a mode switching circuit, and a leak-cut circuit are provided. The first pull-down transistor pulls down an input/output terminal. The mode switching circuit controls on and off of the first pull-down transistor based on an enable signal. The leak-cut circuit turns off the first pull-down transistor when a power supply of the mode switching circuit is shut down.

主权项

1. An interface circuit comprising:
a first pull-down transistor that pulls down an input/output terminal; a self-bias circuit that generates an input voltage based on a divided voltage that is generated by dividing an external voltage applied to the input/output terminal; a second pull-down transistor that is connected in series to the first pull-down transistor; a first control transistor that has power feeding made thereto from the input voltage and turns on the second pull-down transistor when an internal power supply is shut down; a second control transistor that has power feeding made thereto from the internal power supply and turns on the second pull-down transistor when the internal power supply is supplied; a mode switching circuit that has power feeding made thereto from the internal power supply and controls on and off of the first pull-down transistor based on an enable signal; a leak-cut circuit that turns off the first pull-down transistor when the internal power supply is shut down; a first inverter that has power feeding made thereto from the input voltage, the internal power supply input thereto, and controls a gate potential of the second control transistor; and a second inverter that has power feeding made thereto from the input voltage, is connected in series to the first inverter, and controls a gate potential of the first control transistor.