hi.i want to measure the current from solar panel and i ve to send it to microcontroller for MPPT project. the problem is that am using 18W panel of rating 21V and max 1A. which ic has to b used? can i use opamp?
What you are requiring to do is a "current sense" amplifier.
Most IC vendors have chips specific for the purpose. You may also google "hall effect sensors".
As your panel wiring is very likely not going to be grounded, you can use high- or low-side current sensing. Yes, you can use an opamp for this, provided you make sure the voltages at the inputs are within the correct range. Here's an example configuration:
If you are implementing a large gain you will want to compensate for input offset error either through hardware nulling or software compensation (or by using a sufficiently low-input-offset-error opamp).
thank u all.. @ronsimpson i was using tat acs ic oly but it was very sensitive and my 3 ics got spoiled already.can u tell me safer way to handle it? and also tell me how can i get it?