A Delta-Sigma modulator with fast feedback loop is proposed that acts on disturbances introduced by the quantizer and compensates low frequency noise. As a result, an improved modulator is obtained that remains stable for the entire output range but also provides improved noise attenuation like that of a second-order modulator. It is used to directly control the switches of a DC-DC converter operating at multi-MHz switching frequency. Compared to PWM it offers lower output distortion especially when operating at these high switching frequencies.
