| 摘要 |
PURPOSE:To vary a threshold value while holding abrupt output voltage variation and output voltage supply with a level VSS, by supplying a voltage different from a power voltage to a signal inversion part and shifting its output nearly to a power source level. CONSTITUTION:The signal inversion part consisting of an enhancement type FETQ2 and a depletion type FETQ5 is interposed between a power source VDD and the potential at a point A obtained by an enhancement type FETQ1 and a depletion type FETQ6. The output of the signal inversion part is connected to the gate of an enhancement typ FETQ4, whose drain is connected to a power source VSS to lead an output voltage out the FETQ4 from the source. When the potential at the point A is VTC1 and the power voltage of the signal inversion part is VDD-VSS-VTC1, the return circuit threshold value VTC of this constitution is VTC1+VTC2 where VTC2 is a circuit threshold voltage, and the voltage at the point A is varied to vary the circuit threshold value VTC. |
