Miscellaneous active electrical nonlinear devices – circuits – and – Specific signal discriminating without subsequent control – By frequency
Reexamination Certificate
2007-07-10
2007-07-10
Callahan, Timothy P. (Department: 2816)
Miscellaneous active electrical nonlinear devices, circuits, and
Specific signal discriminating without subsequent control
By frequency
C327S040000, C327S042000, C327S047000, C327S048000
Reexamination Certificate
active
10797478
ABSTRACT:
A frequency monitor circuit (FMC) that is part of an integrated circuit chip for monitoring the frequency of one or more clocks present on the chip is disclosed. The FMC includes a reference window generator, operative to output a reference window signal of a given duration, and a clock counter, operative to count all pulses, in any one of the clocks, that occur within the duration of the reference window and to output a corresponding pulse count. The FMC further includes two or more comparators, each operative to compare the pulse count with a respective given threshold value and to output a corresponding indication of frequency deviation. In one configuration, in which the clock is generated on the chip by a frequency multiplier, the reference window generator and the clock counter are shared between the frequency monitor circuit and the frequency multiplier.
REFERENCES:
patent: 4352999 (1982-10-01), Galpin
patent: 4380733 (1983-04-01), Yano et al.
patent: 5418409 (1995-05-01), Kuhn
patent: 5488323 (1996-01-01), Beacham et al.
patent: 5497110 (1996-03-01), Smith
patent: 6008671 (1999-12-01), Kang
patent: 6281699 (2001-08-01), Bishop
patent: 6289055 (2001-09-01), Knotz
patent: 6542013 (2003-04-01), Volk et al.
patent: 6667638 (2003-12-01), Kramer et al.
patent: 6998882 (2006-02-01), Chung
Callahan Timothy P.
Luu An T.
National Semiconductor Corporation
LandOfFree
Clock frequency monitor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Clock frequency monitor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Clock frequency monitor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3760932