Bandpass sigma-delta modulator with anti-resonance cancellation

According to the present invention, the zone passage sigma delta modulator using an acoustic resonator or a micro mechanical resonator is indicated. In order to improve resolution in a high frequency region, an acoustic resonator or a micro mechanical resonator is used instead of an electronic resonator into a sigma delta modulator. The quantized output returns to an input total device using a pair of D/A converter. In the fourth device, a return is performed to two total devices connected in series. In the radio cellular phone system and other uses of which the A/D conversion of high frequency and high resolution is required and which are defined by software, this type of sigma delta modulator is useful. In one case of the operation, a antiresonance signal is removed from a resonator using an offset circuit. A antiresonance offset circuit is offering the signal which should be subtracted from the output of a resonator, and removes a antiresonance ingredient from the output of a resonator. This offset circuit contains the capacitor matched with the static capacity of the resonator. The load of a resonator and the load of an offset network are also matched.