Patent ID: 7019544

Claim:
An electrical test probe for sensing a plurality of electric signals and generating a differential signal, said electrical test probe comprising: (a) a common substrate; (b) a first transmission line on said common substrate, said first transmission line comprising a first signal conductor and a first ground conductor, said first transmission line having a characteristic impedance substantially equal to a first predetermined value; (c) a second transmission line on said common substrate, said second transmission line comprising a second signal conductor and a second ground conductor, said second transmission line having a characteristic impedance substantially equal to a second predetermined value; and (d) a differential amplifier having a first signal input, a second signal input, and a ground input; (i) wherein a first input resistor is coupled between said first signal input and said ground input, said first input resistor having a resistive value substantially equal to said first predetermined value; (ii) wherein a second input resistor is coupled between said second signal input and said ground input, said second input resistor having a resistive value substantially equal to said second predetermined value; (iii) wherein a first end of said first signal conductor is coupled to said first signal input and a first end of said first ground conductor is coupled to said ground input; (iv) wherein a first end of said second signal conductor is coupled to said second signal input and a first end of said second ground conductor is coupled to said ground input; (v) wherein a second end of said first signal conductor is coupled to a first test point and a second end of said first ground conductor is floating; and (vi) wherein a second end of said second signal conductor is coupled to a second test point and a second end of said second ground conductor is floating.