Thermal noise of a resistor is independent of the current passing through it. There are other types of noise produce when current flows but the resistor thermal noise can be express as a mean-square voltage value of 4*k*T*R*(BW) regardless whether its carrying current or not. May I know why you're interested on this? Is it some application where thermal noise is critical? Maybe you can read this RAQ: Resistor Noise can be Deafening, and Hard to Reduce.

Hi,

Thermal noise of a resistor is independent of the current passing through it. There are other types of noise produce when current flows but the resistor thermal noise can be express as a mean-square voltage value of 4*k*T*R*(BW) regardless whether its carrying current or not. May I know why you're interested on this? Is it some application where thermal noise is critical? Maybe you can read this RAQ: Resistor Noise can be Deafening, and Hard to Reduce.

Thanks,

Phil