Im kinda pretty new to Arduino especially in terms of shields for it. Im using sim 7000 shield for arduino from DFRobot. Was working on project to send sms to me when smth happen, for example if temerature will be too high, kinda simple project. So for a week everything was fine, program worked, and my setup was that I had external power supply 12V plugged in and at the same time had USB connected from my laptop to Arduino to program it. As said this worek fine for a week of work. This shield is said that need 7 - 12 V to work. And today smoething happen. I was working with this project as usual and something happen and my arduino poofed, the 5V regulator started smoking, so ofc I instantly unplugged everything. I removed shield from arduino, and checek if USB work, but UBS do not work as well, no diode is lighting up and regulator slowly is heating up while USB is connected. I dont know exactly what happen, as far i remember i had 12V plugged in and USB wasnt, so i plugged USB in and this happen. Idk if smth like this should happen as im rather new to arduino. If someone could tell me what i did wrong, would be very happy to know.
But as arduino is rather dead, im thinking if sim shield could be damaged too. I couldnt check it as i didnt have cables, only had charger and this shield have only micro USB port to connect. SO my question is, could that shield be dead too? Or its rather impossible?