Linear full wave rectifier and method for providing full wave rectified signals

In a linear full wave rectifier circuit adapted to receive an alternating input signal, a method for producing an output signal which is a linear full wave rectified version of the input signal, comprising the steps of:

• providing first non-linear rectifier means for producing an output signal at an output that is a non-linear full wave rectified version of the input signal which is applied to said first non-linear rectifier means;
• providing second non-linear rectifier means having an input and an output, said output being coupled to said output of said first non-linear rectifier means and having substantially identical non-linear transfer characteristics as said first rectifier means;
• and
• providing current feedback means coupled between said output of said first rectifier means and said input of said second rectifier means which is responsive to said output signal from said first rectifier means for producing a signal which is a linear full wave rectified version of the alternating signal by supplying said signal to said input of said second non-linear rectifier means thereby constraining the output signal from said second non-linear rectifier means to be substantially identical to said output signal from said first non-linear rectifier means.

A linear full wave rectifier, comprising:

• a first recitifer circuit having non-linear transfer characteristics which receives an alternating input signal at an input thereof for producing a non-linear full wave rectifier version of said alternating input signal at an output;
• a current mirror circuit having an input coupled to said output of said first rectifier circuit and an output, said current mirror circuit being responsive to said output signal appearing at said output of said first rectifier circuit for producing a substantially identical version thereof at said output thereof;
• a second rectifier circuit having an output coupled to said output of said current mirror circuit and an input, said second rectifier circuit having substantially identical transfer characteristics to said first rectifier circuit;
• and
• feedback circuit means coupled between said output of said current mirror circuit and said input of said second rectifier circuit for producing a signal that is a linear full wave rectified version of said alternating signal and which is supplied to said input of second rectifier circuit thereby constraining the output signal appearing at said output of said second rectifier circuit to be substantially identical to said output signal produced by said first rectifier circuit.