A drive circuit is disclosed including a first feedback circuit designed
to generate a first feedback signal from a first voltage to be controlled
and a first reference voltage. The drive circuit further includes a
signal converter designed to generate a second feedback signal from the
first feedback signal such that the difference between the first feedback
signal and a first amplitude value of a periodic signal approximately
matches the difference between the second feedback signal and a second
amplitude value of the periodic signal. The drive circuit also includes a
first pulse width modulator which receives the first feedback signal and
the periodic signal and generates the first pulse width-modulated signal.
In addition the drive circuit includes a second pulse width modulator
which receives the second feedback signal and the periodic signal and
generates the second pulse width-modulated signal.