Device under test data processing techniques
View Patent ↗A data processing unit has a time information provider for processing a clock or a strobe signal, configured to provide a digitized clock or strobe time information on the basis of the clock or strobe signal and at least one data extraction unit, coupled to the time information provider and configured to select data from a sequence of data samples of a data signal depending on the digitized clock or strobe time information.
1. A data processing unit comprising:
time information provider to encode transition time information on the basis of a sequence of samples of a clock-or-strobe signal, wherein the encoded transition time information describes timing of a transition of the clock-or-strobe signal; and
at least one data extraction unit, coupled to the time information provider, to select data from a sequence of data samples of a data signal depending on the encoded transition time information provided b the time information provider, wherein the sequence of data samples of the data signal are n-fold samples of the data signal sampled with an n-fold frequency clock, wherein n is larger than 1.
2. The data processing unit of claim 1 , wherein the encoded transition time information is represented as a multi-bit value.
3. The data processing unit of claim 1 , wherein the encoded transition time information is represented as an increment-decrement-information.
4. The data processing unit of claim 3 , wherein the increment-decrement-information describes a difference between a timing of a currently detected transition of the clock-or-strobe signal and a timing of a previous transition of the clock-or-strobe signal.
5. The data processing unit of Claim 1 , wherein the encoded transition time information is transferred from the time information provider to the at least one data extraction unit synchronized with a master clock.
6. The data processing, unit of claim 1 , wherein the encoded transition time information is transferred from the time information provider to the at least one data extraction unit asynchronously.
7. The data processing unit of Claim 1 , wherein the encoded transition time information is transferred from the time information provider to the at least one data extraction unit once per I periods of the clock-or-strobe signal, wherein I is greater than 1.
8. The data processing unit of claim 1 , wherein the encoded transition time information is transferred from the time information provider to the at least one data extraction unit once per J data positions of the data signal, wherein J is greater than 1.
9. The data processing unit of Claim 1 , further comprising a correction unit coupled to the at least one data extraction unit, wherein the correction unit influences the selection of data from a sequence of data samples of the data signal, such that a propagation delay difference between the clock-or-strobe signal and the data signal is at least partially compensated.
10. The data processing unit of Claim 1 , further comprising a correction unit coupled to the at least one data extraction unit, wherein the correction unit influences the selection of data from a sequence of data samples of the data signal, such that a propagation delay of the encoded transition time information is at least partially compensated.
11. The data processing unit of claim 1 , further comprising a correction unit coupled to the at least one data extraction unit, wherein the correction unit compensates, at least partially, buffer delays in a data path of the data signal.
12. The data processing unit of claim 1 , wherein the at least one data extraction unit comprises a multiplexer to select data from the sequence of data sample of the data signal based on the encoded transition time information or a function of the encoded transition time information.
13. The data processing unit of claim 1 , wherein the clock-or-strobe signal and the data signal are source-synchronous signals.
14. A method of processing data comprising:
encoding transition time information describing a transition of a clock or strobe signal; and
selecting data from a data signal based on the encoded transition time information, wherein the sequence of data samples of the data signal are n-fold samples of the data signal sampled with an n-fold frequency clock, wherein n is larger than 1.
15. The method according to claim 14 , wherein the encoded transition time information is represented as a multi-bit value describing a time of a transition of the clock-or-strobe signal.
16. The method according to claim 14 , wherein the encoded transition time information is represented as an increment-decrement-information.
17. The method according to claim 14 , wherein;
encoding the transition time information comprises sampling the clock or strobe signal with a first sampling frequency f s1 , which is n-times higher than a first maximum frequency f max1 of the clock or strobe signal to acquire samples of the clock-or-strobe signal and identifying a transition of the clock-or-strobe signal using the samples of the clock-or-strobe signal; and
selecting the data from the data signal comprises sampling the data signal with a second sampling frequency f s2 which is m-times higher than a maximum frequency f max 2 of the data signal to acquire a sequence of samples; and wherein n≧2 and m≧2.