RTC Frequency Correction Using Lookup Table Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional real-time clocks (RTC) in electrical products become inaccurate due to process drift and aging of components, leading to inefficiencies and malfunctions in computer systems that rely on accurate time information.
Innovation Solution
A correction apparatus comprising a measuring module, a setting module, and a timing module that measures frequency signals, generates error setting values, and compensates the frequency signals to produce an accurate real-time clock, using a mapping table to adjust for inaccuracies.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a conventional RTC uses a crystal oscillator with R-C circuit, then the device structure is simple and cost-effective, but the time accuracy deteriorates due to process drift and component aging
Solution Approach 1:
The patent applies preliminary action by pre-calculating and storing compensation values in a lookup table during the manufacturing process. The frequency measurement and compensation values are determined in advance for different temperature and aging conditions, allowing the RTC to be corrected without real-time complex calculations, thus improving time accuracy while maintaining simple runtime operation
Solution Approach 2:
The patent introduces an intermediary compensation mechanism that uses a lookup table storing pre-calculated correction values. This intermediary structure mediates between the frequency generator and the timing module, providing corrected frequency values based on measured deviations without requiring complex real-time computation, thereby improving accuracy while keeping the device structure manageable
2Manufacturing precision
If the RTC operates without frequency compensation, then the device complexity is low, but the time accuracy deteriorates due to process drift and component aging
Solution Approach 1:
The patent implements feedback by continuously measuring the actual frequency output of the crystal oscillator and comparing it against the nominal frequency value. Based on the measured deviation, the system retrieves appropriate compensation values from the lookup table and applies corrections to subsequent timing operations, creating a closed-loop system that automatically maintains time accuracy despite component drift and aging
Solution Approach 2:
The patent applies parameter changes by storing multiple compensation values in the lookup table corresponding to different frequency deviation conditions, temperature ranges, and aging stages. The system dynamically selects and applies the appropriate compensation parameter based on current operating conditions, enabling adaptive time accuracy improvement without requiring complex real-time calculation hardware
Data Source
AI summary
A clock device is provided for generating a real-time clock. The clock device includes a frequency generator, a measuring module, a setting module and a timing module. The frequency generator generates a frequency signal. The measuring module is coupled to the frequency generator for measuring the frequency signal and generating a measuring frequency value. The setting module is coupled to the measuring module for generating an error setting value corresponding to the measuring frequency value. The timing module is coupled to the frequency generator and the setting module for compensating the frequency signal according to the error setting value and generating the real-time clock.