PURPOSE: To simplify the circuit constitution without using a drive signal by providing the 3rd and 4th MOSTs whose pre-charged input signal is inputted to the 1st and 2nd MOSTs and grounding the input signal by its output voltage.

CONSTITUTION: A pre-charge signal is inputted to terminals 26, 27 between times t0 and t1, input terminals 22, 23 are pre-charged to [V] level through P- MOSTs 24, 25. Output terminals 34, 35 are discharged by a discharge signal ' at the same time. The and ' are inverted at the time t1, a P-MOST 29 is turned on as an input signal IN' is decreased and then a voltage at the terminal 35 starts increasing soon. Then an N-MOST 33 is turned on and a level at the terminal 23 is lowered further. The operations above are repeated and the input level is decreased rapidly and the output level is rised rapidly to [V] level and high speed read of the input signal is conducted.