| 摘要 |
PURPOSE:To enable MOS integration, by arranging a p-n junction diode, a MOSFET switch, a MOS gate electrode-inversion layer capacitance type capacitor and a MOS operational amplifier to form a circuit. CONSTITUTION:MOSFETs 21 and 22 form a current mirror and a bias voltage is supplied from a bias circuit comprising MOSFETs 23-25 to drive diodes 11 and 12 by a constant current. A capacitor 31 samples an electric charge proportional to a voltage drop of the diode 12 to hold it and a capacitor 32 samples an electric charge proportional to a difference in voltage drop between the diodes 11 and 12 to hold it. An operational amplifier 30 and a capacitor 33 and up the charge held as sample by the capacitors 31 and 32 to sample and hold them. Then, a detection circuit containing piezoelectric resistance elements 1-4 is driven by an output voltage of the operational amplifier 30 held by the capacitor 33. The circuit thus arranged permits adaption thereof to a MOS integration. |
