| 摘要 |
A switch-mode modulator operating at a two-level voltage and including an alternating output stage (3), an optional output filter (5) and a feedback including a function block (14) with a transfer function (MFB). The modulator furthermore includes a forward block (12) provided with means for calculating the difference between the signal (14a) originating from the function block (14) and a reference signal (REF) as well as with a transfer function (MFW). The output (13) of the forward block (12) is the input of a Schmitt-trigger (9), which generates switch on signals (2) for changing the output stage. The output voltage (VOUT) of the modulator applying either after the optional output filter (5) or the output stage (3) is fed back through the function block (14) so as to generate the signal (14a) fed back. The transfer function of the function block (14) and of the forward block (12) is chosen both in response to the transfer function of the output filter (5) and in response to the desired total open-loop-transfer function of the modulator. |
