Clock control circuit

Details Clock control circuit Clock control circuit

1998-10-05

2001-01-30

Butler, Dennis M. (Department: 2787)

Electrical computers and digital processing systems: support

Clock, pulse, or timing signal generation or analysis

Multiple or variable intervals or frequencies

C713S503000

Reexamination Certificate

active

06182234

ABSTRACT:

BACKGROUND OF THE INVENTION
This invention relates to a clock control circuit which generates various internal clocks that have specific phase relationships with an external clock.
In semiconductor systems, including a synchronous DRAM (SDRAM), to fetch the data read from a memory surely outside the memory, it is necessary to set a time interval called a data window and output the data within the data window. To set such a data window, it is necessary to generate an internal clock having a specific phase relationship with an external clock. To achieve this, a clock control circuit is used.
A conventional clock control circuit, however, has the problem that it does not operate properly when the cycle time of an external clock is short.
BRIEF SUMMARY OF THE INVENTION
An object of the present invention is to provide a clock control circuit which operates properly even when the cycle time of an external clock is short.
Another object of the present invention is to provide a semiconductor memory device which is capable of setting a data window properly even when the cycle time of an external clock is short and fetching the data read from a memory surely outside the memory.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.


REFERENCES:
patent: 5294842 (1994-03-01), Iknaian et al.
patent: 5309035 (1994-05-01), Watson, Jr. et al.
patent: 5745533 (1998-04-01), Asada et al.
patent: 5867432 (1999-02-01), Toda
patent: 5867693 (1999-02-01), Wang et al.
patent: 7262076 (1995-10-01), None

Affiliated with

Also associated with

Rating

Clock control circuit 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 control circuit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Clock control circuit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2480152