drain of the pmos transistor 112 and a gate connected to the drain of the nmos transistor 121 the resistor 132 is connected between a source of the nmos transistor 122 and the gnd terminal 102 the nmos transistor 123 has a drain connected to the output terminal 105 and a drain of the pmos transistor 113 and a gate connected to the gate of the nmos transistor 122 the current measuring resistor connecting terminal 104 is connected to the measuring current input terminal 103 and a source of the nmos transistor 123 the current measuring resistor 141 has one end connected to the current measuring resistor connecting terminal 104 and the other end connected to the gnd terminal 102 the nmos transistor 124 has a gate connected to one end of the resistor 131 a drain connected to the current measuring resistor connecting terminal 104 and a source connected to the gnd terminal 102 the nmos transistors 121 and 124 respectively have a normal threshold voltage threshold voltages of the nmos transistors 122 and 123 are lower than those of the nmos transistors 121 and 124 in the reference voltage circuit 10 in the current detection circuit 100 configured as described above a current flowing through the nmos transistor 122 low in threshold voltage is copied to a drain current of the pmos transistor 111.