| 摘要 |
<P>PROBLEM TO BE SOLVED: To protect an internal circuit from a negative current caused by ESD which flows in via a parasitic diode developed in a transistor for a switch. <P>SOLUTION: A fourth n-channel MOSFET (Mn4) has a source terminal and a back gate terminal connected to each other. A switch element is connected between the source terminal of the fourth n-channel MOSFET (Mn4) and a ground potential to bring the source terminal of the fourth n-channel MOSFET (Mn4) to the ground potential when the fourth n-channel MOSFET (Mn4) is off. A protection circuit 40 is disposed between a junction of the source terminal of the fourth n-channel MOSFET (Mn4) and an input terminal of the switch element, and the ground potential to lead a negative current flowing in from a drain terminal of the fourth n-channel MOSFET (Mn4) owing to electrostatic discharge to the ground potential. <P>COPYRIGHT: (C)2013,JPO&INPIT |
