Probing test apparatus

Claim 1

A probing test apparatus for testing electric properties of a circuit while sending a test signal to the circuit to be tested, comprising: a probe card having a plurality of probes and first terminals to be contacted with and to be electrically connected to conductive pads of the circuit to be tested; a test head having a signal transmitting circuit through which the test signal is transmitted to each of the probes; a performance board having second terminals electrically connected to said signal transmitting circuit of the test head; a contact ring interposed between the performance board and the probe card and whose impedance has been adjusted; a plurality of first-type pogopins each having a pair of pin members contacting the first and second terminals to transmit the test signal to each of the probes said first-type pogopins being arranged in the contact ring; and a plurality of second-type pogopins each having a pair of pin members contacting the first and second terminals, said second-type pogopins being arranged in the contact ring, and spaced from said first-type pogopins in a plane perpendicular to the axes of said pin members, said second-type pogopins electrically grounded, wherein an interval L 1 in the plane between each of the first-type pogopins and some of the second-type pogopins which are the nearest to said each of the first-type pogopins is smaller than an interval L 2 in the plane between said each of the first-type pogopins and an adjacent first-type pogopin which is the nearest to said each of the first-type pogopins, and wherein for each one of said first-type pogopins the closest pogopins thereto in said plane are all second-type pogopins such that said one of said first-type pogopins is surrounded by said second type pogopins.