Patent application number | Description | Published |
20090002087 | LOW-POWER FAST-STARTUP OSCILLATOR WITH DIGITAL FEEDBACK CONTROL - Embodiments of the present invention provide a system for controlling a startup time of an oscillator circuit. The system includes a variable current source coupled to the oscillator circuit, wherein a startup time of the oscillator circuit is proportional to a bias current input into the oscillator circuit from the variable current source. The system also includes a control mechanism coupled to the variable current source and to the output of the oscillator circuit. Upon startup, the control mechanism is configured to adjust the variable current source to input a large startup bias current into the oscillator circuit. After the oscillator circuit outputs a predetermined number of oscillations during startup, the control mechanism is configured to adjust the variable current source to decrease its current to a smaller steady-state bias current into the oscillator circuit. | 01-01-2009 |
20120294336 | FRACTIONAL FREQUENCY DIVISION OR MULTIPLICATION USING AN OVERSAMPLED PHASE ROTATOR - Circuits and systems for generating multiple frequencies are disclosed. In some embodiments, a circuit can include a first node, a second node, and a programmable phase rotator. The first node can receive a first signal having frequency f | 11-22-2012 |
20130285641 | GROUND OFFSET MONITOR AND COMPENSATOR - Methods and systems are described for monitoring and compensating an offset between a reference voltage used in a first device and a corresponding reference voltage used in a second device. The first device can include offset circuitry. The offset circuitry receives two voltage signals. The first voltage signal is equal to a first voltage value that is used as a reference voltage in the first device. The second voltage signal can be a time-varying voltage signal that has a known relationship with a second voltage value that is used as a reference voltage in the second device. The offset circuitry can then determine the second voltage value from the second voltage signal, and output an offset value based on a difference between the first voltage value and the second voltage value. | 10-31-2013 |