Semiconductor device, semiconductor system, and electronic apparatus

A semiconductor device comprising:

• a semiconductor element;
• a connection terminal configured to output a signal based on an output of the semiconductor element;
• a protection circuit connected to the connection terminal;
• and
• a voltage limiting element connected to the connection terminal,
• wherein the protection circuit is connected to a first power supply line having a first potential and a second power supply line having a second potential lower than the first potential,
• wherein a potential supplied to the voltage limiting element is higher than the second potential and lower than the first potential,
• wherein the semiconductor element includes a first impurity region formed in a semiconductor substrate,
• wherein the voltage limiting element includes a second impurity region formed in the semiconductor substrate,
• wherein the semiconductor substrate is provided with the protection circuit, and
• wherein a PN junction exists between the first impurity region and the second impurity region.