Patent ID: 7030584

Claim:
A control circuit, comprising: a single input terminal for receiving digital signals and analog control signals; said digital signals being in a first digital state when below a first level, and being in a second digital state when above a second level; said analog signals being within a range that is greater than said first level and less than said second level; a comparator circuit coupled to said single input terminal for providing a first output when the level at said single input terminal is below said first level or when the level at said single input terminal is above said second level; said comparator circuit providing a second output when the level at said single input terminal is between said first level and said second level; an oscillator, said oscillator providing a pulse waveform at a first output and as saw tooth waveform at a second output; a pulse width modulated comparator having a first input coupled to said single input terminal and a second input coupled to said oscillate second output and having an output; a circuit coupled to said comparator, said oscillator first output and to said pulse width modulated comparator output, said circuit operable to generate pulse width modulated control signals in response to digital input signals at said single input terminal and in response to analog input signals at said single input terminal.