Low power compact peak detector with improved accuracy

An electronic circuit including a peak detector, wherein said peak detector comprises:

• an input circuit comprising first, second, third, and fourth transistors of a first conductivity type, each having a first current terminal coupled to a control node, each having a second current terminal coupled to a bias node, and each having a control terminal receiving a corresponding one of first and second in-phase signals and first and second quadrature signals, and a fifth transistor of said first conductivity type having a first current terminal coupled to a current node, having a second current terminal coupled to said bias node, and having a control terminal coupled to an output node, and wherein said first, second, third, fourth, and fifth transistors of said first conductivity type have the same size;
• a bias circuit coupled between said bias node and a source reference voltage node that establishes a predetermined bias current from said bias node to said source reference voltage node;
• a current mirror coupled to a source voltage node, said current node and said control node, wherein said current mirror mirrors current flowing through said fifth transistor of said first conductivity type from said current node and into said first, second, third, and fourth transistors of said first conductivity type via said control node;
• and
• an output circuit comprising a first transistor of a second conductivity type having a first current terminal coupled to said source voltage node, having a second current terminal coupled to said output node, and having a control terminal coupled to said control node, and comprising a capacitor coupled between said output node and said source reference voltage node.