| 摘要 |
PROBLEM TO BE SOLVED: To provide a current detection circuit which can cancel detection of a current change due to charging of parasitic capacity.SOLUTION: The current detection circuit 100 includes: transistors 101 and 102 constituting a CMOS inverter to which a signal S11 is given; a transistor 103 having a drain electrode connected to a source electrode of the transistor 102 and a source electrode to which a power supply voltage VDD is given; resistors 123 and 124 connected in series between the drain electrode of the transistor 103 and a ground line GND; an operational amplifier to which a voltage at a connection point between the resistor 123 and the resistor 124 and a power supply voltage Vref are input and whose output terminal is connected to a gate electrode of the transistor 103; a current monitor circuit monitoring a current flowing through the transistor 103, comparing a monitor current with a reference current, and detecting a current change in an input/output terminal; and capacitor 127 connected to the current monitor circuit and charged by the monitor current. |
