Vibrator Circuit Compensation for Thermal Transient Frequency Drift
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing temperature compensated crystal oscillators face errors in temperature compensation due to delayed temperature changes in vibrators separate from the IC chip, leading to fluctuations in oscillation frequency when the output buffer is switched on or off.
Innovation Solution
A vibrator device with a circuit device that includes a temperature sensor, a transient response compensation circuit, a temperature compensation circuit, and a heat source circuit, which compensates for the difference between the transient response of the temperature detected by the sensor and the vibrator, using a digital filter to improve temperature compensation accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the output buffer is switched on or off to control signal output, then the signal output is controlled, but the temperature sensor rapidly detects temperature change while the vibrator's temperature change is delayed, causing temperature compensation error and oscillation frequency fluctuation
Solution Approach 1:
The transient response compensation circuit performs preliminary compensation for the delayed temperature response of the vibrator. When the heat source circuit state is switched, the circuit proactively adjusts the temperature compensation based on the expected delayed response pattern, rather than waiting for the actual temperature change to occur. This preliminary action ensures that the temperature compensation remains accurate despite the inherent thermal lag in the vibrator.
2Reliability
If the circuit device is disposed apart from the vibrator to reduce wraparound, then wraparound is reduced, but the temperature sensor detects temperature change faster than the vibrator, causing transient response difference
Solution Approach 1:
The transient response compensation circuit acts as an intermediary between the temperature sensor and the temperature compensation circuit. It receives the temperature signal from the sensor, processes it by adding the predetermined transient response compensation, and then provides the compensated signal to the temperature compensation circuit. This intermediary function bridges the gap between the fast-responding sensor and the slow-responding vibrator, ensuring consistent transient response characteristics.
3Device complexity
If the temperature sensor is placed inside the IC chip to monitor temperature, then temperature detection is integrated, but the detected temperature changes rapidly while the vibrator's temperature changes slowly, creating compensation error
Solution Approach 1:
The system changes the parameter of the temperature signal by adding a predetermined transient response compensation value. This parameter modification transforms the rapidly changing temperature sensor signal into a compensated signal that reflects the slower temperature changes of the vibrator. The compensation circuit adjusts the temperature parameter dynamically based on the operational state of the heat source circuit.
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 effectively reduces frequency deviations and improves temperature compensation accuracy by compensating for the delay in temperature changes in the vibrator, ensuring stable oscillation frequency even when the heat source circuit's state is switched.
Implementation Method 1
a temperature sensor configured to generate a temperature signal corresponding to a detected temperature
Implementation Method 2
a transient response compensation circuit configured to compensate for, when the first state and the second state of the heat source circuit are switched, a difference between a transient response of a temperature detected by the temperature sensor and a transient response of a temperature of the vibrator
Implementation Method 3
a temperature compensation circuit configured to compensate for temperature characteristics of a drive state of the vibrator based on the temperature signal
Data Source
AI summary
A vibrator device includes: a vibrator; and a circuit device disposed apart from the vibrator, in which the circuit device includes a drive circuit configured to drive the vibrator, a temperature sensor configured to generate a temperature signal corresponding to a detected temperature, a temperature compensation circuit configured to compensate for temperature characteristics of a drive state of the vibrator based on the temperature signal, a heat source circuit configured to operate in a first state or in a second state in which current consumption is different from current consumption in the first state, and a transient response compensation circuit configured to compensate for, when the first state and the second state of the heat source circuit are switched, a difference between a transient response of a temperature detected by the temperature sensor and a transient response of a temperature of the vibrator.