A SWITCH MODE POWER SUPPLY

摘要

A current sensing circuit senses the momentary varying current (I1) flowing through the first impedance (Rds-on), and a second current (Is) which is related to the varying momentary current (I1). A gain stage (GS) corrects the amplitude of the momentary information (MI), which represents the momentary varying current (I1), with a correction factor (CS) to obtain corrected momentary information (CMI). The correction factor (CS) is obtained by integrating (INT) the difference of the corrected momentary information (CMI) and the sensed reference information (SAI) representing the second current (Is). Due to the integration, the disturbances of the sensed currents decrease.