公开(公告)号：US10545182B2

公开(公告)日：2020-01-28

申请号：US15072926

申请日：2016-03-17

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Minghua Fu ,  Kaichien Tsai ,  Prashanth Saidu

IPC: G01R21/133 ,  G01R35/00

Abstract: A system such as an electric meter includes a single-ended analog-to-digital converter which is susceptible to crosstalk. Methods and apparatus are disclosed to calibrate and cancel crosstalk effects. The system determines whether voltage-induced cross-talk is in-phase or out-of-phase with respect to voltage. The system determines a first calibration factor based on minimum and maximum measured current values and voltage. If the cross-talk is in-phase, the system sets a second calibration factor to 0. If the cross-talk is out-of-phase, the system computes the second calibration factor based on a measured current when a power factor angle is set to 90 degrees. Calibration factors may be stored in the multi-channel system. In use, the system measures current and voltage and computes the actual current, voltage and power based on the measured current and voltage by employing a crosstalk cancellation technique using the calibration factors.