Current type inverter circuit, current type logic circuit, current type latch circuit, semiconductor integrated circuit, current type ring oscillator, voltage-controlled oscillator and PLL circuit

摘要

A current type inverter circuit or the like is obtained which operates at a high speed with a low power consumption. A reference power source 1 has one end connected to a power source VDD and the other source receiving a reference current Iref. A drain and a gate of an NMOS transistor Q1 of a current mirror circuit CM1, as an input part, receive an input current Iin. A drain of an NMOS transistor Q2 is connected to an node N1 of the other end side of the reference power source 1 as an output part. As an input part, a drain and a gate of an NMOS transistor Q3 of a current mirror circuit CM2 are connected to the node N1 while a drain of an NMOS transistor Q4 functions as an output part for outputting an output current Iout. The transistors are set so that all of the conditions TS11, TS21 and TS1TS2 1 are satisfied where TS1 is a ratio of the size of the NMOS transistor Q2 to the size of the NMOS transistor Q1 and TS2 is a ratio of the size of the NMOS transistor Q4 to the size of the NMOS transistor Q3.