To provide a charge detection circuit that allows an easy adjustment of an input gain of a differential amplifier circuit.
In a differential charge detection circuit, one end of physical quantity detection sensors 1A and 1B composed of either a charge generation type sensor or capacitance change type sensor is connected to a negative input terminal of a differential amplifier circuit 1, the other end is connected to a positive input terminal of the differential amplifier circuit 1, a feedback resistor Rf and a feedback capacitor Cf are connected in parallel between an output terminal and the negative input terminal of the differential amplifier circuit 1, and a cancel resistor Rc and a cancel capacitor Cc are connected in parallel between the positive input terminal and a reference voltage of the differential amplifier circuit 1. Drain voltage adjustment circuits 12 and 13, which adjust at least one of drain voltages of two field effect transistors FET1 and FET2 to which a positive and negative differential inputs of the differential amplifier circuit 1 are input, respectively, are provided to allow the differential charge detection circuit to adjust a gain of at least one of the positive and negative differential inputs.
| WO/1998/024176 | CHARGE SENSITIVE AMPLIFIER WITH HIGH COMMON MODE SIGNAL REJECTION |
| JPS6367007 | CHARGE AMPLIFIER ARRAY |
MATSUO NAOYUKI
KISHIRO MASAMI
| JP2002100936A | 2002-04-05 | |||
| JP2007259409A | 2007-10-04 | |||
| JPS5988923U | 1984-06-16 |
Hide Tanaka Tetsu