Hi Satish,

LCD hangs; MCU crashes; battery does not last long;

Such general lamenting dont take you anywhere near a solution.

What LCD module ? Which MCU ? ANd what voltage fluctuations are you suspecting ?

A tip : If you have a good running code for LCD, just save that as a separate code and keep it handy. Whenever you LCD walks out on you in your main line code, just try out this code. You can be that much closer to a solution.

Raghu