2022-02-09 05:50 PM
I want to interfacing industrial analogue sensors with STM32F030C8T6TR so I need to convert signal in to 0-3.3v signal.
4-20ma to 0-3.3v
0-10v to 0-3.3v
1) For converting signal which is good way using opamp or voltage divider?
2) It is possible using one circuit for both ip and get 0-3.3V op?
2022-02-10 02:42 AM
Usually a special device is used as a 4-20mA receiver to minimise interference. Your favourite search engine will give you suggestions for a "4-20mA receiver".
Theoretically, such a receiver can also be built with a voltage divider and possibly an opamp as a voltage follower, but this is limited to very simple systems because of the greater susceptibility to interference and significantly lower accuracy/linearity.
For 0-10V you really only need a voltage divider, maybe with an opamp as voltage follower for impedance matching.
If you really want to do without a dedicated 4-20mA receiver and can accept the lower accuracy, you could think about building both with a voltage divider and voltage follower, possibly with switchable inputs.
Regards
/Peter