PURPOSE: To output a signal with an amplitude smaller than that of a power supply by connecting plural NMOS transistors(TRs) in diode connection in series and giving an input signal to one gate and outputting an output signal from a drain.

CONSTITUTION: When a level of an input terminal 16 is 0V, no current flows to an amplitude limiter circuit, and the voltage at an output terminal 15 gets lower than the voltage of a power supply 12 by a sum of threshold levels of TRs 11, 13. This state continues till a voltage applied to the input terminal 16 increases from 0V and reaches a sum of threshold levels of TRs 14, 17. When an applied voltage to the input terminal 16 is larger than 2VT (VT is a threshold level of each TR), the TRs 14, 17 are turned on and a level of the output terminal 15 starts decreasing. Moreover, when a level at the input terminal 16 rises, the TR 14 reaches the non-saturation region and an output voltage is not much reduced.