Patent ID: 7859351

Claim:
A driver device which is connected with a vibrator to form an oscillation loop and causes the vibrator to produce driving vibrations by applying a rectangular-wave driving signal to the vibrator when measuring physical quantity using an output signal obtained by synchronously detecting a detection signal output from the vibrator, the driver device comprising: a current-voltage converter which converts a current value of an oscillation signal in the oscillation loop into a voltage value; and a first comparator which outputs a signal corresponding to a result of comparison between an output signal from the current-voltage converter and a given reference signal, the first comparator being connected with a high-potential-side power supply and a low-potential-side power supply, forming the oscillation loop together with the vibrator and having a current limiting function of limiting an amount of output current, the current limiting function being a function of limiting current in a current path connected to at least one of the high-potential-side power supply and the low-potential-side power supply; the driver device causing the vibrator to produce the driving vibrations based on the rectangular-wave driving signal output from the first comparator.