Semiconductor device having a protective circuit

A semiconductor device comprising a first source terminal, a second source terminal, an internal circuit including at least one functional MOS transistor having a specific function, a first source line connecting said first source terminal and said internal circuit, a second source line connecting said second source terminal and said internal circuit, and a protective circuit including a first protective MOS transistor having a gate, a source connected to said second source line, and a drain directly connected to said gate and said first source line, and a second protective MOS transistor having a gate directly connected to said source of said first protective MOS transistor, a source connected to said second source line and a drain connected to said first source line, said first protective MOS transistor having a threshold voltage having an absolute magnitude higher than a voltage between said power source line and said ground line.

A semiconductor device comprising a first terminal, a second terminal, an internal circuit including at least one functional MOS transistor having a specific function, a first line connecting said first terminal and said internal circuit, a second line connecting said second terminal and said internal circuit, one of said first line and said second line being a first source line, the other of said first line and said second line being a signal line having a potential equal to a potential of said first source line or a second source line, and a protective circuit including a protective MOS transistor having a gate, a source, and a drain directly connected to said gate and said first line, and a bipolar transistor having an emitter connected to said second line, a collector connected to said first line and a base directly connected to said source of said n-channel MOS transistor, said protective MOS transistor having a threshold voltage having an absolute magnitude which is higher than a potential voltage between said first source line and said second source line.

A semiconductor device comprising a first terminal, a second terminal, an internal circuit including at least one functional MOS transistor having a specific function, a first line connecting said first terminal and said internal circuit, a second line connecting said second terminal and said internal circuit, one of said first line and said second line being a first source line, the other of said first line and said second line being a signal line having a potential equal to a potential of said first source line or a second source line, and a protective circuit including a first protective MOS transistor having a gate, a source connected to said signal line, and a drain directly connected to said gate and said first source line, and a second protective MOS transistor having a gate directly connected to said source of said first protective MOS transistor, a source connected to said signal line and a drain connected to said first source line, said first protective MOS transistor having a threshold voltage having an absolute magnitude higher than a voltage between said first source line and said second source line.