公开(公告)号：US10263794B2

公开(公告)日：2019-04-16

申请号：US15582445

申请日：2017-04-28

Applicant: Linear Technology Corporation

Inventor： Michael Paul ,  David M. Stover ,  Heath D. Stewart ,  Jeffrey L. Heath

IPC: H04L12/10 ,  G06F1/26 ,  H04L12/40

Abstract: The invention pertains to systems where DC power is supplied by a PSE to a PD, such as over differential data wire pairs. IEEE standards require a minimum current to be drawn from the PD in order for the PSE to continue supplying the DC voltage. If the PD is in a low power mode, the PSE will normally discontinue supplying the DC voltage, which then requires a new detection and classification routine for powering up again. To avoid this, a “maintain power signature” controller provides a periodic current pulse by a current source connected between the PD input and the PD's full bridge rectifier. Any droop in the DC voltage that reverse biases the full bridge rectifier while the PD is in its low power mode will not affect the current pulse, so the PSE continues to supply the DC voltage.

公开(公告)号：US20170338969A1

公开(公告)日：2017-11-23

申请号：US15582445

申请日：2017-04-28

Applicant: Linear Technology Corporation

Inventor： Michael Paul ,  David M. Stover ,  Heath D. Stewart ,  Jeffrey L. Heath

IPC: H04L12/10

CPC classification number: H04L12/10 ,  G06F1/26 ,  H04L12/40045

Abstract: The invention pertains to systems where DC power is supplied by a PSE to a PD, such as over differential data wire pairs. IEEE standards require a minimum current to be drawn from the PD in order for the PSE to continue supplying the DC voltage. If the PD is in a low power mode, the PSE will normally discontinue supplying the DC voltage, which then requires a new detection and classification routine for powering up again. To avoid this, a “maintain power signature” controller provides a periodic current pulse by a current source connected between the PD input and the PD's full bridge rectifier. Any droop in the DC voltage that reverse biases the full bridge rectifier while the PD is in its low power mode will not affect the current pulse, so the PSE continues to supply the DC voltage.