Patent attributes
A calibration circuit including a plurality of first resistance components, a plurality of second resistance components, and a first feedback system is provided. The first feedback system selects M1 first resistance components and N1 second resistance components so that a first combination of the M1 first resistance components and the N1 second resistance components has a first predetermined relationship with the impedance of a first resistor. The first feedback system selects M2 first resistance components and N2 second resistance components so that a second combination of the M2 first resistance components and the N2 second resistance components has a second predetermined relationship with the impedance of the first resistor. Based on the values of M1, N1, M2, N2, and a target impedance, the first feedback system generates a first set of calibration signals for a plurality of third resistance components and generates a second set of calibration signals for a plurality of fourth resistance components.