Abstract: In one embodiment, a wiring open detection circuit includes a signal processing circuit, a terminal, a diode, and an open decision circuit. The signal processing circuit is connected to one end of a first wiring and outputs a signal processed signal to the first wiring. The terminal is connected to the other end of the first wiring. The diode has one end connected to the terminal. The open decision circuit applies a first voltage to the other end of the diode, and detects change in a current flowing in the first wiring to decide whether or not the first wiring is open.

Abstract: According to an embodiment, a semiconductor integrated circuit includes a signal processing circuit with a first transistor and a second transistor connected in series, and a third transistor. The signal processing circuit is supplied with power from a power source, and receives a first input signal at control terminals of the first transistor and the second transistor, and execute signal processing based on the first input signal to output an output signal. The third transistor is provided between the signal processing circuit and a ground potential and receives a second input signal at a control terminal of the third transistor, the second input signal obtained by level-shifting the first input signal and thereby having a smaller signal amplitude than a signal amplitude of the first input signal, and be turned on or off based on the second input signal.

Abstract: In one embodiment, a wiring open detection circuit includes a signal processing circuit, a terminal, a diode, and an open decision circuit. The signal processing circuit is connected to one end of a first wiring and outputs a signal processed signal to the first wiring. The terminal is connected to the other end of the first wiring. The diode has one end connected to the terminal. The open decision circuit applies a first voltage to the other end of the diode, and detects change in a current flowing in the first wiring to decide whether or not the first wiring is open.

Abstract: According to one embodiment, a level shift, circuit includes first to sixth transistors, is supplied with a power supply voltage, boosts the voltage of an input signal, and outputs an output signal whose high-level voltage is at the power source voltage. A first control voltage is applied to a control terminal of the first transistor and the second transistor. A second control voltage is applied to a control terminal of the third transistor and the fourth transistor. The fifth transistor has a control terminal to which an input signal is inputted. The sixth transistor has a control terminal to which an inverted signal of the input signal is inputted.

Abstract: Incorporated in a MOS semicustom integrated circuit are pull-up and pull-down MOS transistors adapted for pulling up or down the potential of a signal line connecting a protection circuit with an internal circuit to be protected from electrostatic breakdown. The MOS transistors have their drains connected together to the signal line and their sources connected to a pull-up power supply node or pull-down power supply node as required. The MOS transistor acts as a pull-up or pull-down transistor when its source is connected to the pull-up or pull-down supply node by master slice wiring, and its drain junction acts as a protective diode when its source remains open. Thus, owing to the protection functions of the drain junction and diodes in the protection circuit, the electrostatic breakdown strength of the internal circuit can be increased without increase in the occupied area of the protection circuit in the integrated circuit.