Temperature-Compensated Oscillator Control for Low-Jitter Tuning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing oscillating circuitry, such as phase-locked loops, face noise performance issues like jitter due to temperature fluctuations, which previous solutions have not adequately addressed.
Innovation Solution
The oscillating circuitry is configured to impose corrected fine value changes on the controllable oscillator when coarse value changes occur, using a calibration mode to measure fine value changes at a reference temperature and a temperature-correction mode to account for temperature differences, thereby reducing noise and distortion in the output signal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the oscillating circuitry operates over a wide temperature range, then the adaptability is improved, but the noise performance deteriorates due to temperature-induced frequency drift
Solution Approach 1:
The patent pre-calibrates the relationship between coarse value changes and required fine value compensations at different temperatures during manufacturing. This preliminary characterization allows the system to predict and correct for temperature-induced frequency drift before operation, enabling wide temperature range operation while maintaining low jitter performance.
Solution Approach 2:
The system continuously monitors the output frequency and uses feedback control to adjust the fine value in response to temperature changes. When temperature drift causes frequency deviation, the feedback mechanism triggers appropriate fine value corrections to maintain the target frequency, thereby reducing temperature-induced noise and jitter during operation.
2Stability of the object's composition
If control-loop adjustments are applied frequently to maintain target frequency, then the frequency stability is improved, but the settling time increases due to multiple adjustments
Solution Approach 1:
The patent pre-determines the appropriate fine value corrections needed for various coarse value changes based on temperature and frequency requirements. By having these corrections prepared in advance, the system can apply the correct fine value adjustment immediately when a coarse value change occurs, avoiding iterative trial-and-error adjustments and reducing settling time while maintaining frequency stability.
Solution Approach 2:
The system dynamically selects the appropriate fine value correction from pre-characterized data based on current operating conditions (temperature, target frequency, coarse value). This dynamic selection allows the control loop to make optimal adjustments quickly, improving both settling time and frequency stability by avoiding unnecessary intermediate adjustments.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present disclosure relates to oscillating circuitry, comprising a controllable oscillator operable to generate an output signal having an output frequency dependent on a coarse value and a fine value, the coarse value causing the output frequency to be within an associated band of output frequencies and the fine value controlling the output frequency within that band; and control circuitry operable to generate the coarse and fine values so as to control the controllable oscillator. In certain arrangements, the control circuitry compensates for temperature fluctuations during operation.