A 1.5-V-100-MU-W DELTA-SIGMA MODULATOR WITH 12-B DYNAMIC-RANGE USING THE SWITCHED-OPAMP TECHNIQUE

The design and implementation of a very low supply voltage/low power D elta Sigma modulator is presented. It is based on the switched-opamp t echnique, which allows low voltage operation with a standard process a nd without voltage multiplication. The design methodology is illustrat ed with a second-order single-loop Delta Sigma modulator. The chip is implemented in a 0.7-mu m CMOS process with standard threshold voltage s. The power supply is 1.5 V and the power dissipation is only 100 mu W. The measured dynamic range in the speech bandwidth of 300-3400 Hz i s 12 b. The total harmonic distortion (THD) is lower than -72 dB.