| 摘要 |
PURPOSE:To prevent a function detecting and amplifying a logic input signal from being lost even with radiant ray irradiation by providing a signal detection amplifier circuit, a reference voltage generating circuit and a threshold voltage fluctuation compensating circuit. CONSTITUTION:If a logic signal detection and amplification circuit is subjected to radiation of a radiant ray, a threshold voltage VT1 of a signal detection amplification field effect transistor (TR) Q1 of the signal detection and amplification circuit 1 is fluctuated. The threshold voltage VT2 of a threshold voltage fluctuation compensation field effect TR Q2 is fluctuated similarly as the fluctuation of the threshold voltage VT1 of the signal detection and amplification field effect TR Q1 in this case. Since a reference voltage given to the gate of the signal detection and amplification field effect TR Q1 is fluctuated by the fluctuation of the threshold voltage VT1, the logic threshold voltage of the signal detection and amplification circuit 1 viewed from a logic signal input line 5 is compensated for its deviation from a median between a level of '0' in binary representation of a logical input signal and a level of '1' in binary representation. |
