1results about How to "Increase output impedance" patented technology

This application discloses a current calibration loop and method for current calibration of a current-controlled DAC. The current calibration loop includes: a selected reference current source and a selected current source to be calibrated; a clamping management module that clamps the output nodes of the two sources to the same fixed potential to discharge the static current of the two output nodes in different calibration modes, retaining only the current difference; an error comparison module that amplifies the current difference into a voltage difference and outputs the comparison result; a calibration control logic module that generates a calibration control signal based on the comparison result; and a calibration module that injects error compensation current into the output nodes according to the calibration control signal, so that the compensated output current of the selected current source to be calibrated is equal to the reference current provided by the selected reference current source. By discharging most of the static current and retaining only the current difference for comparison, it can respond promptly to a wide current range, significantly improve the current calibration accuracy, and adapt to various calibration modes.