Oscillators – Ring oscillators
Patent
1989-11-08
1990-12-18
Grimm, Siegfried H.
Oscillators
Ring oscillators
331179, 331DIG3, H03B 500
Patent
active
049789279
ABSTRACT:
Each section (e.g., 102) of the ring oscillator consists of three two-input NOR gates; one in the feedforward path (108), one in the feedback path (112), and one in the crossover path (110). The center frequency of the oscillator is controlled by enabling and disabling the appropriate gates, such that a single closed loop path is formed. The gates in the feedforward and crossover paths are directly enabled or disabled (to disable, either input is held high) from a control circuit (FIG. 2). The gates in the feedback path, however, are indirectly enabled and disabled. To enable a particular feedback path gate (e.g., 118), either the corresponding crossover gate (116) is disabled, or the corresponding feedforward gate is disabled (114) and the crossover gate (122) in the following section is enabled. The later causes the feedback gate (124) in the following section to be disabled, thereby removing the remaining sections (106) of the oscillator from the closed loop path. The NOR gates are implemented as a differential amplifier (FIG. 5) having two transistors (610 and 612) in the input leg and one transistor (616) with its base connected to a regulated voltage (Vr) in the opposite leg. The output of the NOR gate is taken from the collectors of the input transistors. The propagation delay of the oscillator signal through the gate is minimal because, to switch the output state of the gate, only the state of one of the input transistors (610 or 612) must be changed. The short propagation delay through the gate permits high frequency operation, as well as the ability to program small incremental steps in the center frequency of the oscillator.
REFERENCES:
patent: 3931588 (1976-01-01), Gehweiler
patent: 4105950 (1978-08-01), Dingwall
patent: 4392105 (1983-07-01), McLeod
patent: 4517532 (1985-05-01), Neidorff
patent: 4617529 (1986-10-01), Suzuki
patent: 4625181 (1986-11-01), Bichler
patent: 4656369 (1987-04-01), Lou
patent: 4680480 (1987-07-01), Hopta
patent: 4694261 (1987-09-01), Ewen et al.
patent: 4695808 (1987-09-01), Cabaniss et al.
IBM Technical Disclosure Bulletin, vol. 30, No. 3, Aug. 1987, pp. 1181-1182.
IBM Technical Disclosure Bulletin, vol. 31, No. 2, Jul. 1988, pp. 154-156.
Gaudenzi Gene J.
Hausman Kristen A.
Mosley Joseph M.
Tempest Susan L.
Grimm Siegfried H.
International Business Machines - Corporation
McKinley Martin J.
LandOfFree
Programmable voltage controlled ring oscillator does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Programmable voltage controlled ring oscillator, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Programmable voltage controlled ring oscillator will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1428173