The task was somehow to equip one system with a bunch of temperature sensors. And to equip as inexpensively as possible.
The results of the research (which, in my opinion, turned out to be quite elegant) I propose for consideration in this article.
This article discusses contact methods for measuring temperatures in systems with a microcontroller.
Let's first list some features / requirements of temperature measurements:
Inertia
In most cases, temperature processes are very inert.
The consequence of this is that the speed of repeated measurements, as a rule, is not very important.
Whatever device we control, whether it is a refrigerator control system or a system that detects the overheating of an element, the temperature measurement speed is unlikely to be critical. We measure the temperature in 0.0001 seconds, or in 0.1 second, or even (for many cases, suitable) in 10 seconds - not so important.
Consumers would rather be interested in the accuracy of temperature measurements than speed.
Noise immunity
Often the conductors to the temperature sensor are quite long. Nearby devices create a set of interference / interference. It is required to level out the influence of interference
on the measurement accuracy as much as possible .
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- It is quite simple to add galvanic isolation to the proposed circuit and significantly increase noise immunity and safety.
Total
The proposed method seems to have the lowest possible hardware cost of measuring temperature, high noise immunity. However, the fee for this is the need to perform a certain number of mathematical operations by the microcontroller.