[54] CLOCK SIGNAL DISTRIBUTION AND SYNCHRONIZATION IN A DIGITAL SYSTEM
[75] Inventor: Ingemar Soderquist, Linkoping, Sweden
[73] Assignee: Saab Dynamics Aktiebolag, Linkoping, Sweden
[21] Appl. No.: 09/011,026
[22] PCT Filed: Aug. 8, 1996
[86] PCT No.: PCT/SE96/01010
§ 371 Date: Feb. 6, 1998
§ 102(e) Date: Feb. 6, 1998 [87] PCT Pub. No.: WO97/06478
PCT Pub. Date: Feb. 20, 1997
[30] Foreign Application Priority Data
Aug. 8, 1995 [SE] Sweden 9502780
[51] Int. CI.6 H03L 7/07; H03L 7/081;
H03K 5/15
[52] U.S. CI 331/2; 331/18; 331/74;
327/149; 327/295
[58] Field of Search 331/1 A, 2, 18,
331/25, 55, 74, 172; 327/147-150, 291,
295, 297
[56] References Cited
U.S. PATENT DOCUMENTS
4,847,516 7/1989 Fujita et al 331/2 X
4,868,522 9/1989 Popat et al 331/2
5,008,636 4/1991 Markinson et al 331/2
5,122,679 6/1992 Ishii et al 307/269
5,204,555 4/1993 Graham et al 307/465
5,448,193 9/1995 Baumert et al 327/156
5,481,573 1/1996 lacobowitz et al 375/356
5,539,344 7/1996 Hatakenaka .
5,565,816 10/1996 Coteus 331/2
5,764,092 6/1998 Wada et al 327/271
OTHER PUBLICATIONS
G. Koetzle. "Computer Clock Distribution System with Programmable Delay and Automatic Adjustment." IBM Technical Disclosure Bulletin vol. 18, No. 6, Nov. 1975, p. 1912.
Primary Examiner—David Mis
Attorney, Agent, or Firm—Pollock, Vande Sande & Amernick
[57] ABSTRACT
A method for increasing a working speed in a synchronous digital system, which includes a plurality ol separate system parts, and for permitting communication between at least two ol the system parts. A common relerence signal having a relerence frequency is distributed to all system parts. An internal signal clock oscillator ol each system part is phase locked to the relerence signal. Data is communicated between the at least two system parts by relating the relerence signal with the internal clock signal ol each ol the two system parts by adjusting a phase position ol the internal clock signal ol a second ol the two system parts dependent upon a time delay ol the data communicated from the first system part to the second system part so that the phase positions ol the internal clock signals correspond.
24 Claims, 3 Drawing Sheets
