Sensor device with series circuit of MOS switch and capacitor

摘要

In a related art sensor device, an output voltage of the sensor device is fixed not to a power supply voltage or a ground potential but to an intermediate potential upon disconnection of a power supply line or a ground line. A sensor device 1 is composed of: a detection element 8 whose voltage Vsen changes depending on a detected physical quantity; an output circuit configured by MOS switches 4 to 6, 7, 9, 10 and 12 to 17, capacitors 2, 11 and 18, an operational amplifier 19, a reference voltage source 20, and output NMOS transistor 21; a series circuit of the MOS switch 4 and the capacitor 2, the series circuit being arranged in a negative feedback part of the output circuit; and a diode 3 that connects a well electrode of the MOS switch 4 and a power supply terminal Vcc.

主权项

1. A sensor device for detecting a predetermined physical quantity, the sensor device including a power supply terminal and a ground terminal which are supplied with power from outside, an output terminal which outputs an output signal of the sensor device to the outside as an analog voltage, and an output circuit which generates an output signal of the output terminal, the sensor device comprising:
a series circuit of a MOS switch and a capacitor, the series circuit being arranged in a negative feedback part of the output circuit; and an element which serves as a diode connected to a well electrode of the MOS switch.