Methods and structures for dynamically reducing DC offset

A method of operating an amplifier system, wherein the amplifying system comprises an amplifier characterized as having an offset and comprising a first signal input, a second signal input, an output, a first amplifying terminal and a second amplifying terminal, the method comprising:

• coupling a resistance of a resistive digital to analog converter between the first and second amplifying terminals;
• coupling a load to the output and to the second input of the amplifier;
• and
• reducing the offset by adjusting a location of a current source along the resistance between the first amplifying terminal and the second amplifying terminal.

An amplifier, comprising:

• a resistive digital to analog converter having a resistive chain of resistors at which points along the resistive chain can be selected for receiving a current source;
• a differential amplifier having a first input, a second input, an output, a first amplifying terminal, and a second amplifying terminal;
• a load coupled to the output and to the second input of the amplifier;
• and
• an offset detector which selects at which point in the resistive chain the current source is applied to optimize an offset between the first and second inputs.