Image Number 4 for United States Patent #8130128.
In a particular embodiment, a circuit device is disclosed that includes a data generator adapted to output a random pulse sequence having a particular spectral shape. The data generator includes a feedback loop with a transfer function, the output of which may be altered by limiter circuitry to increase stability of the data generator. The circuit device may further include, for example, a pulse edge control circuit to selectively apply a carrier suppression operation to at least one pulse-width modulated (PWM) signal in response to the random pulse sequence to produce at least one modulated PWM output signal. In such an example, the spectral energy associated with a PWM carrier of the modulated PWM output signal at a carrier frequency and associated harmonics is changed such that the modulated PWM output signal has a spectral shape defined by the particular spectral shape.