JPS5461863A - Waveform shaping circuit - Google Patents

Abstract

PURPOSE:To obtain a waveform shaping circuit which has high stability against noises and delay time nearly as short as that of a general switching circuit. CONSTITUTION:If the relations of Vt<->1<=Vt<->2<Vt<+>2<Vt<+>1 and Vt<->1<Vt<->3< Vt<+>3<=Vt<+>1 are established on Schmitt circuits G1, G2 and G3 whose threshold levels are Vt<+>1XVt<->2, Vt<+>2XVt<->2 and Vt<+>3XVt<->3, common input IN before Vt<+>1 makes G1 output ''0'', the output of G2 is outputted via inhibit gate A2 and the OR gate, and output G2 is extracted afterward. When the selection is made so that Vt<+>2-Vt<+>1>Vt<+>2-Vt<->3 and Vt<+>3-Vt<->3>Vt<+>2-Vt<->3 will be satisfied, expecially Vt<+>2=Vt<->3, the obtained output has equal rise and fall threshold levels as well as a general switching circuit, and when Vt<+>2 is less than Vt<->3, effects can be obtained which a conventional Schmitt circuit or switching circuit has not. In this way, a waveform shaping circuit can be realized which is stable against noises.