公开(公告)号：US09966832B1

公开(公告)日：2018-05-08

申请号：US15590305

申请日：2017-05-09

Applicant: Linear Technology Corporation

Inventor： Michael T. Engelhardt ,  Leonard Shtargot

IPC: H02M1/15 ,  H02M1/14 ,  H02M3/156 ,  H03K5/134 ,  H03K5/135 ,  H03K5/14 ,  H03K17/16 ,  H02M1/00 ,  H02M1/38

CPC classification number: H02M1/143 ,  H02M3/156 ,  H02M2001/0025 ,  H02M2003/1566 ,  H03K5/134 ,  H03K5/135 ,  H03K5/14

Abstract: A predicted ripple in the feedback voltage of a switching converter is generated, based on the ripple over a certain number of recent switching cycles. The DC portion of the feedback voltage is filtered out. This predicted feedback voltage ripple is then added to a fixed reference voltage to create a compensated reference voltage. The compensated reference voltage is applied to the non-inverting input of an error amplifier, and the feedback voltage (having a DC component and ripple) is applied to the inverting input of the error amplifier. Thus, substantially the same ripple component is applied to both inputs and cancels out. Therefore, the output of the error amplifier is not affected by the ripple in the feedback voltage, and a non-rippling control voltage is generated by the error amplifier. As a result, the gain-bandwidth product of the converter can be increased for faster response to transients.