Zero-cross switch control with high precision over wide operating range

An adaptive delta-sigma modulator which can be utilized for the zero-cross switching control of resistive heaters with AC line for thermal control is proposed. By adjusting the horizon width for the cost function of the modulator control scheme according to the command signal, the modulator has both a good performance of quantum noise suppression and a wide operating range simultaneously. A numerical example is shown to demonstrate that the proposed adaptive scheme works well.