Voltage Comparator Calibration for Current Drift in Temperature Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional temperature detecting circuits face inaccuracies due to current source drift caused by temperature variations or other factors, leading to unreliable temperature detection results.
Innovation Solution
A voltage comparing circuit and method that includes a comparator, time interval computing unit, switch module, current sources, capacitors, and a capacitance adjusting unit, allowing for calibration of the current sources to maintain accurate temperature detection by adjusting capacitance to match ideal charging time intervals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional current sources are used for temperature detection, then the detection circuit can operate continuously, but the current drifts due to temperature variation causing inaccurate detection results
Solution Approach 1:
The patent adjusts the capacitance value of the first capacitor to compensate for current source drift. By changing the capacitance parameter, the charging time interval is recalibrated to match the ideal value, thereby maintaining accurate temperature detection despite current variations. This is implemented through the capacitance adjusting unit that modifies C1 based on detected drift conditions.
Solution Approach 2:
The patent performs preliminary calibration by computing the charging time interval and comparing it with an ideal value before actual temperature detection. The capacitance is adjusted in advance to correct any drift, ensuring that the current source operates accurately at the start of the detection process. This preliminary adjustment prevents accumulation of errors during continuous operation.
2Measurement precision
If the capacitance of the first capacitor is adjusted to compensate for current drift, then the temperature detection accuracy improves, but the device complexity increases due to additional components
Solution Approach 1:
The patent combines the capacitance adjusting unit with the existing voltage comparing circuit and time interval computing unit. The adjustment mechanism is integrated into the same operational framework, allowing capacitance modification without requiring a separate independent calibration system. This merging approach minimizes additional complexity while achieving the desired precision improvement.
Solution Approach 2:
The circuit performs self-calibration by automatically detecting the charging time interval and adjusting the capacitance value to match the ideal value. The system uses its own operational characteristics (charging time) as the basis for adjustment, eliminating the need for external calibration equipment or manual intervention. This self-service capability improves precision without proportionally increasing system complexity.
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 ensures accurate voltage comparing and temperature detecting results by calibrating the current sources, mitigating the effects of drift and improving the precision of temperature measurements.
Implementation Method 1
a first current source, comprising a first charging terminal coupled to the first input terminal and the second input terminal; a first capacitor, coupled to the first current source at the first charging terminal
Data Source
AI summary
A temperature detecting circuit comprising: a comparator, comprising a first comparing terminal and a second comparing terminal; a time interval computing unit; a switch module, coupled to the first comparing terminal and the second comparing terminal, comprising a reference voltage terminal coupled to a reference voltage source, and comprising a first input terminal, a second input terminal and a third input terminal; a first current source, comprising a first charging terminal coupled to the first input terminal and the second input terminal; a first capacitor, coupled to the first current source at the first charging terminal; a capacitance adjusting unit, coupled to the first capacitor; a second current source, comprising a second charging terminal coupled to the third input terminal, wherein the second current source is a current source which provides a constant current; and a second capacitor, coupled to the second current source at the second charging terminal.