US 2008/0177489 A1 · SYSTEM AND CIRCUIT FOR CONSTRUCTING A SYNCHRONOUS SIGNAL DIAGRAM FROM ASYNCHRONOUSLY SAMPLED DATA

Abstract

A system and circuit for constructing a synchronous signal diagram from asynchronous sampled data provides a low cost and production-integrable technique for providing a signal diagram. The data signal is edge-detected and asynchronously sampled (or alternatively a clock signal is latched). The data signal or a second signal is compared to a settable threshold voltage and sampled. The edge and comparison data are folded according to a swept timebase to find a minimum jitter period. The crossing of the signal diagram edges is determined from a peak of a histogram of the folded edge data. A histogram of ratios of the sample values versus displacement from the position of the crossing location is generated for each threshold voltage. The technique is repeated over a range of settable threshold voltages. Then, the ratio counts are differentiated across the histograms with respect to threshold voltage, from which a signal diagram is populated.

Claims20

Dependent claims

A workstation computer system comprising a processor for executing program instructions coupled to a memory for storing program instructions and data, wherein said program instructions comprise program instructions for generating a signal diagram of a signal under measurement, said program instructions comprising program instructions for:

collecting first samples of indications of edge positions of a first signal at regular intervals having a sampling period differing from a multiple of a period of said first signal;
collecting second samples of values of said signal under measurement at said regular intervals;
determining a timebase period corresponding to a relationship between said sampling period and said period of said first signal from said first samples;
analyzing said second samples in accordance with said determined timebase to provide said signal diagram of said values of said signal under measurement across said period of said first signal;
and
displaying said signal diagram.

3 more elements

A computer program product comprising computer-readable storage media encoding program instructions for execution within a computer system, wherein said program instructions comprise program instructions for generating a signal diagram of a signal under measurement, said program instructions comprising program instructions for:

collecting first samples of indications of edge positions of a first signal at regular intervals having a sampling period differing from a multiple of a period of said first signal;
collecting second samples of values of said signal under measurement at said regular intervals;
determining a timebase period corresponding to a relationship between said sampling period and said period of said first signal from said first samples;
analyzing said second samples in accordance with said determined timebase to provide said signal diagram of said values of said signal under measurement across said period of said first signal;
and
displaying said signal diagram.

3 more elements

Dependencies are inferred from the claim text.

System and circuit for constructing a synchronous signal diagram from asynchronously sampled data

Life of this patent

System and circuit for constructing a synchronous signal diagram from asynchronously sampled data

Life of this patent

Abstract

Claims20