DC offset compensation circuit for a signal amplifier

A DC offset compensation circuit comprising:

• a signal amplifier producing a first analog signal at an output thereof;
• a reference circuit producing a second analog signal;
• a first sample and hold circuit having an input connected to said output of said signal amplifier and an output;
• a comparator circuit having a first input connected to said output of said first sample and hold circuit, a second input receiving said second analog signal and an output producing a comparator output signal;
• a counter circuit responsive to a first state of said comparator output signal to periodically update a digital count value thereof, said counter circuit responsive to a second state of said comparator output signal to maintain a current value of said digital count value;
• and
• a converter circuit responsive to said digital count value to produce a third analog signal corresponding thereto, said signal amplifier responsive to said third analog signal to adjust a DC offset voltage attributable thereto.

A DC offset compensation circuit comprising:

• a signal amplifier producing a first analog signal;
• a reference circuit producing a second analog signal;
• a comparator circuit responsive to said first and second analog signals to produce a comparator output signal as a function thereof;
• a counter circuit having a number of outputs producing a corresponding number of digital output signals indicative of a digital count value thereof;
• a state machine having a first input receiving said comparator output signal, said state machine responsive to a first state of said comparator output signal to periodically update said digital count value of said counter circuit and responsive to a second state of said comparator output signal to maintain a current value of said digital count value of said counter circuit;
• and
• a converter circuit responsive to said digital count value of said counter circuit to produce a third analog signal corresponding thereto, said signal amplifier responsive to said third analog signal to adjust a DC offset voltage attributable thereto.