Automatic compensation of an AC attenuator using a digital to capacitance converter

A system for compensating an AC attenuator, comprising:

• a plurality of capacitors having weighted values, wherein the plurality of capacitors are adapted to be coupled in parallel with a resistor of the AC attenuator;
• a plurality of switches, wherein a switch is coupled to an input of each of the plurality of capacitors;
• a memory element coupled to the plurality of switches, wherein the memory element stores a value which is operable to open/close selected switches, thereby configuring a capacitance value among the plurality of capacitors for compensation of the AC attenuator.

A method of compensating frequency response of an attenuator, comprising the steps of:

• storing a value in a memory element, wherein the value indicates an open/closed state of a plurality of switches;
• the memory element providing the value to the plurality of switches to selectively open/close the plurality of switches;
• the switches selectively coupling a corresponding plurality of capacitors having different weighted values to the attenuator in response to the memory element providing the value, thereby configuring a virtual trimmer impedance for the attenuator.

A digital to capacitance converter, comprising:

• a plurality of capacitors coupled in parallel, wherein the plurality of capacitors have weighted values;
• a plurality of switches, wherein a switch is coupled to an input of each of the plurality of capacitors;
• a memory element coupled to the plurality of switches, wherein the memory element stores a value which is operable to open/close selected switches, thereby configuring a capacitance value among the plurality of capacitors for impedance compensation.