Patent ID: 7365598

Claim:
Switch-mode modulator operating at a two-level output voltage and including a forward loop and a feedback including a function block ( 14 ) with a transfer function (MFB), the forward loop including an alternating output stage ( 3 ), an optional output filter ( 5 ) and a forward block ( 12 ) having a transfer function (MFW) and being provided with means for calculating the difference between a feedback signal ( 14 a ) originating from said function block ( 14 ) and a reference signal (REF), where an output ( 13 ) of the forward block ( 12 ) is the input of a Schmitt-trigger ( 9 ), said Schmitt-trigger generating switch on signals ( 2 ) for switching the alternating output stage, characterized by the forward loop having an output voltage (V out ) being the output of the modulator and being fed back through the function block ( 14 ) so as to generate the signal ( 14 a ) fed back, and where the transfer function (MFB) of the function block ( 14 ) and the transfer function (MFW) of the forward block ( 12 ) is chosen based on the transfer function of the output filter ( 5 ) as well as on a desired total open-loop-transfer function of the modulator.