RC Oscillator Circuit Using Capacitance Multiplication for Low Frequency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing oscillators face challenges in achieving low operation frequencies with large RC values, leading to increased size and costs, while advanced capacitor manufacturing technologies require complex and costly processes.
Innovation Solution
A resistor-capacitor oscillator design with a capacitor having an enlarged effective capacitance, utilizing a negative amplifier configuration to increase capacitance without increasing size or power consumption, and adjusting frequency through resistor and capacitor networks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If a high RC value is used to achieve low operation frequency, then the oscillation frequency is reduced, but the oscillator size increases
Solution Approach 1:
The patent changes the effective capacitance parameter by introducing a capacitor between the input and output of the inverter, which creates a feedback path that multiplies the effective capacitance value without increasing the physical capacitor size, thereby maintaining low frequency operation with smaller oscillator size
Solution Approach 2:
The capacitor connected between the inverter input and output creates a feedback mechanism where the inverter's gain amplifies the capacitance effect, effectively multiplying the capacitance value and enabling low frequency operation without proportionally increasing component sizes
2Area of stationary object
If high-density capacitor manufacturing technology is used to achieve larger capacitance in smaller size, then capacitor size is reduced, but manufacturing complexity and cost increase
Solution Approach 1:
The inverter acts as an intermediary element that multiplies the effective capacitance of a standard capacitor through its gain, allowing the use of conventional capacitor manufacturing processes while achieving the effect of a much larger capacitor
Solution Approach 2:
The inverter serves multiple functions: it provides signal inversion for the oscillator operation and simultaneously acts as a capacitance multiplier through its feedback path, eliminating the need for specialized high-density capacitor fabrication
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution achieves a significant reduction in capacitor size and maintains performance, reducing costs without specialized fabrication processes, enabling efficient low-frequency oscillation.
Implementation Method 1
the first inverter is configured as a negative amplifier, and the first capacitive device and the resistor network are configured to determine a frequency of an oscillator
Data Source
AI summary
An apparatus includes a first inverter, a first capacitor connected between the input terminal and the output terminal of the first inverter, a second inverter, a third inverter, a second capacitor connected between the input terminal and the output terminal of the third inverter, a fourth inverter, a plurality of resistors coupled in series between an output of a logic gate and a first input of the logic gate, and a third capacitor connected between the first input of the logic gate and ground, wherein the logic gate has a second input configured to receive an enable signal, and wherein each of the first inverter and the third inverter is configured as a negative amplifier such that an effective capacitance between its input and output terminals is greater than a physical capacitance of the corresponding capacitor.