GND plane

[karimoviç]

hello , why we should use ground plane in the pcb ?

[Paul van Avesaath]

a gnd plane is your reference, if you think about signal integrety you need a GND plane underneath your signals to ensure your signal propogates coreclty... in some cases you do not want to have a gnd plane underneath you signals, but then it is indicated by the datasheet if you should remove it. for simple boards it is common that you do not have a gnd plane, but the you should polygon fill you bottom with GND to give at least some refefernce for signals.. p.s. do some research on signla return path.. https://www.youtube.com/watch?v=CDqref32tPU