Electricity: measuring and testing – Measuring – testing – or sensing electricity – per se – Frequency of cyclic current or voltage
Reexamination Certificate
2006-02-07
2006-02-07
Nguyen, Vincent Q. (Department: 2858)
Electricity: measuring and testing
Measuring, testing, or sensing electricity, per se
Frequency of cyclic current or voltage
C714S744000, C327S156000
Reexamination Certificate
active
06995554
ABSTRACT:
A delay-locked loop (DLL) of an integrated circuit (IC) with testing circuitry and a method for testing a DLL. During test mode, a phase comparator of the DLL receives a test clock in place of the reference clock and determines the phase difference between the test clock and the dock fed back to the DLL from a clock buffer tree. A variable delay element of the DLL then shifts the reference clock in time by an amount that depends on that phase difference. The variable delay element can be exercised by varying the phase of the test clock with respect to the reference clock by a known phase offset to cause the variable delay element to produce a range of delays. Whether the variable delay element is functioning properly can be determined by checking whether the phase of the test clock is aligned with the phase of the feedback clock.
REFERENCES:
patent: 5717353 (1998-02-01), Fujimoto
patent: 2003/0067332 (2003-04-01), Mikhalev et al.
Gilsdorf Michael Joseph
Loke Alvin Leng Sun
Meier Peter Jacob
Rearick Jeffrey R.
LandOfFree
Delay-locked loop and a method of testing a delay-locked loop does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Delay-locked loop and a method of testing a delay-locked loop, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Delay-locked loop and a method of testing a delay-locked loop will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3661536