Patent ID: 6588276
Filing Date: 2003-07-08
Classification: G01P

Abstract:
An acceleration sensor comprising:first and second piezoelectric vibrators in which reverse stresses are generated by acceleration; a bridge circuit that includes a first impedance circuit including the first piezoelectric vibrator, a second impedance circuit including the second piezoelectric vibrator, a first load impedance circuit including a first capacitor, and a second load impedance circuit including a second capacitor, said first impedance circuit and said second impedance circuit are connected to a first junction point, said first impedance circuit and said first load impedance circuit are connected to a second junction point, said second impedance circuit and said second load impedance circuit are connected to a third junction point, and said first load impedance circuit and said second load impedance circuit are connected to a fourth junction point having a potential which defines a reference potential; a voltage-dividing impedance circuit provided between said second junction point and said third junction point; a feedback-signal processing circuit for feeding back the signal of a voltage-dividing point of said voltage-dividing impedance circuit to said first junction point; wherein an oscillating circuit is arranged; and a phase-difference-signal processing circuit which detects an oscillation-output-phase difference between said second junction point and said third junction point and which outputs an acceleration-detection signal.