Patent ID: 8350541
Filing Date: 2013-01-08
Classification: H02M,Y02B

Abstract:
1. An apparatus, comprising: an error amplifier, a first switch and a second switch, wherein the first switch is coupled to a first input of the error amplifier and the second switch is coupled to a first sampling element; a sampling controller configured to sample an output voltage of a power converter during a sampling phase at an appropriate time slot by opening a control loop, wherein the sampling is enabled by closing the second switch and the control loop is opened by opening the first switch, thereby causing the sampling phase to take place during an open-loop configuration; and a soft-start circuit configured to enable soft-starting of an internal soft-start reference voltage to start from a sampled non-zero output voltage and to control the internal soft-start reference voltage to a predetermined target value in order to pre-charge the output voltage close to an input voltage level, or to continue charging the output voltage to a predetermined output voltage value, wherein the non-zero output voltage is the start voltage for the soft start reference voltage and the soft-starting takes place during a soft-start phase which is triggered by closing the first switch and opening the second switch, thereby causing the soft-start phase to take place during a closed-loop configuration.