公开(公告)号：US08964919B2

公开(公告)日：2015-02-24

申请号：US13674864

申请日：2012-11-12

Applicant: NVIDIA Corporation

Inventor： Stephen G. Tell

IPC: H04L7/00 ,  G06F5/10 ,  G06F7/499

CPC classification number: H04L7/0012 ,  G06F5/10 ,  G06F7/49989 ,  G06F2205/106 ,  H04L7/005

Abstract: A system and method are provided for determining a time for safely sampling a signal of a clock domain. In one embodiment, a phase estimate of a first clock domain is calculated based on a relative frequency estimate between a second clock domain and the first clock domain and, based on the phase estimate, a first time during which a signal from the first clock domain is unchanging such that the signal is capable of being safely sampled by the second clock domain is determined to generate a first sampled signal in the second clock domain. Additionally, an updated phase estimate is calculated, and, based on the updated phase estimate, a second time during which the signal from the first clock domain is changing such that the signal is not capable of being safely sampled by the second clock domain is determined. During the second time the first sampled signal in the second clock domain is maintained.

Abstract translation: 提供了一种用于确定对时钟域的信号进行安全采样的时间的系统和方法。 在一个实施例中，基于第二时钟域和第一时钟域之间的相对频率估计，并且基于相位估计，计算来自第一时钟域的信号的第一时间，第一时钟域的相位估计 是不变的，使得能够被第二时钟域安全采样的信号被确定为在第二时钟域中产生第一采样信号。 另外，计算更新的相位估计，并且基于更新的相位估计，确定来自第一时钟域的信号改变的第二时间，使得信号不能被第二时钟域安全地采样 。 在第二时间期间，维持第二时钟域中的第一采样信号。