Greetings,

This may be a silly question, but this has been on my mind for some time now.

I've noticed that if i connect some leds to any pic pins, during programming some of them blink.

My doubt is:

I have some projects where my pic's source is 3V and i have connected 3V components to it's I/Os ( sensors, displays ).
I can isolate the pic's VDD with a jumper for the programmer and have the PGD and PGC dedicated for programming. The problem is the voltage generated on the other pins when programming because the programming voltage is higher than 3V.

Can the 3V components be damaged while programming the Pic?
Is there a solution for these cases?

Thanks