Capacitance Bank Anti-Parallel Cells Frequency Resolution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing oscillator circuits are limited by the size of available capacitors, which restricts the frequency resolution due to a fixed minimum capacitance step, making it difficult to achieve higher frequency resolution in applications requiring finer frequency adjustments.
Innovation Solution
A capacitance bank system utilizing anti-parallel voltage-controlled capacitors with a control word to selectively vary capacitance, allowing for a smaller capacitance step than the smallest available capacitor, achieved through a combination of capacitance cells with ON and OFF states and a sigma delta modulator for finer control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional capacitors are used in oscillator circuits, then the circuit structure is simple, but the frequency resolution is limited due to fixed minimum capacitance step
Solution Approach 1:
The capacitance bank is divided into multiple capacitance cells (first capacitance cell, second capacitance cell, etc.), each capable of being independently controlled in ON or OFF states. This segmentation allows the total capacitance to be adjusted in smaller incremental steps, thereby improving frequency resolution without requiring a single large complex capacitor.
Solution Approach 2:
The capacitance bank employs voltage-controlled capacitors that can dynamically switch between different capacitance values based on control signals. This dynamic capability enables real-time adjustment of the oscillation frequency with fine resolution, transforming the static capacitor into an adaptive component that responds to control inputs.
2Measurement precision
If the capacitance step is reduced for higher frequency resolution, then the frequency adjustment precision improves, but the capacitor size becomes impractically small
Solution Approach 1:
Instead of manufacturing a single capacitor with impractically small capacitance value, the system segments the capacitance function across multiple larger capacitors. Each capacitor in the capacitance bank has a manageable size, but their combined controlled configuration achieves the equivalent of a smaller effective capacitance step, making fabrication practical while maintaining precision.
Solution Approach 2:
The capacitance cells are nested within the capacitance bank structure, with each cell containing voltage-controlled capacitors that can be independently activated. This nested organization allows the system to achieve fine capacitance steps through combinatorial control of multiple larger capacitors, rather than relying on a single small capacitor that would be difficult to manufacture.
Data Source
AI summary
A capacitance bank system includes a plurality of voltage controlled capacitance cells and an output node. The plurality of capacitance cells have an anti-parallel configuration. The plurality of capacitance cells are configured to selectively provide cell capacitances. The output node is coupled to the plurality of capacitance cells. The output node is configured to provide an input capacitance step smaller than a minimum physical capacitor supported by a particular technology.