Device for investigating thermal stability of characteristics of voltage-to-frequiency converters

The article presents the research results on a device for automatic measurement of the temperature stability of the output characteristics of voltage-to-frequency converters. The device can be used to measure mechanical stresses in the ship's hull. The main source of information on the state of the mechanical stress on the hull of the ship is the integrated monitoring system. Monitoring methods are based on measuring the frequency of the output signals from the sensors based on strain gages, which have a wide scatter of values for parameters and characteristics and depend on external factors. A possible solution to this problem is to use a device that would convert the analog sensor signal into a more noise-immune signal of another type, for example, voltage-to-frequency converter. It is for such systems based on synchronous integrated converters that the authors have developed a device for automatic measurement of the temperature stability of the output characteristics of frequency converters. Such device can measure the thermal stability of the convertor automatically, which makes it possible to analyze the effect of temperature on the output characteristics of the converter and to experimentally study the sensors in a wide range of operating temperatures (from room temperature to 70℃). The study of the thermal stability of the characteristics of such sensors made it possible to confirm the quality of its electronic components and to determine which parameters need to be adjusted. The device is a set of units, one of them being a control circuit based on the ATmega-16 RISC microcontroller. This design and the developed algorithm for the device operation makes it possible to determine the output frequency with a high accuracy (with a measurement time of 1 sec, the accuracy reaches 0.05%). The developed device allows finding the ways to increase the thermal stability of mechanical stress sensors based on integral converters.