Patent
Frequency synthesizer having compensation for nonlinearities
TLDR
In this article, the frequency of a VCO is switched by changing the division ratio of a variable ratio frequency divider in the feedback path of the loop, at the time of switching, a prepositioning voltage is applied to the VCO to realize fast frequency switching.Abstract:
In a phase locked loop frequency synthesizer, the frequency of a VCO is switched by changing the division ratio of a variable ratio frequency divider in the feedback path of the loop. At the time of switching, a prepositioning voltage is applied to the VCO to realize fast frequency switching. To correct for nonlinear response of the VCO, the prepositioning voltage is adjusted according to information received from a voltage measuring circuit connected to the VCO control circuit.read more
Citations
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Patent
Fast settling phase locked loop
TL;DR: In this paper, an analog error correction signal is generated by sampling any residual error coming from the phase detector, and generating the analog correction signal to counter the residual error, and the switch between a phase detector output and a VCO input to open the PLL during a frequency change is provided.
Patent
Programmable microcontroller architecture(mixed analog/digital)
Warren Snyder,Monte Mar +1 more
TL;DR: In this article, a programmable array with both continuous time analog blocks and Switched Capacitor analog blocks are offered on a single chip along with programmable digital blocks, which can communicate together.
Patent
Self-calibrating phase-lock loop with auto-trim operations for selecting an appropriate oscillator operating curve
William B. Wilson,Un-Ku Moon +1 more
TL;DR: A phase-lock loop (PLL) has an oscillator having a plurality of operating curves, which are automatically trimmed to an appropriate oscillator operating curve for use during normal PLL operations as discussed by the authors.
Patent
Microcontroller Programmable System on a Chip
Warren Snyder,Monte Mar +1 more
TL;DR: In this article, the authors describe a microcontroller device having a microprocessor, programmable memory components, and programmable analog and digital blocks, which are configurable based on programming information stored in the memory components.
Patent
Self-calibrating voltage-controlled oscillator for asynchronous phase applications
Un-Ku Moon,William B. Wilson +1 more
TL;DR: In this article, a phase-lock loop (PLL) auto-trim is used to select an appropriate oscillator operating curve for use during normal PLL operations, where the state machine uses different signals to determine whether the center frequency of each operating curve in the sequence is above or below the desired nominal operating frequency.
References
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Patent
Frequency prepositioning for an indirect frequency synthesizer
TL;DR: In this paper, a memory device for storing the values of the prepositioning voltage at each transition to each frequency, thus making the device self-adaptive and capable of self-testing.
Patent
Phase lock loop prepositioning apparatus with feedback control
TL;DR: In this paper, a feedback-controlled current pump is coupled to the loop filter capacitor of a phase lock loop to provide a coarse prepositioning voltage and thereby accelerate the lockup process on a new frequency.
Patent
Frequency synthesizer with learning circuit
Ronald W. Kipp,Henry C. Johnson +1 more
TL;DR: In this article, a phase-locked loop is used to produce a signal at any of a plurality of alternating frequency values depending on the value of a command signal applied to the output circuit.