Printed circuit board circuit test fixture with adjustable density of test probes mounted thereon

A printed circuit board (PCB) test fixture with adjustable density of test probes mounted thereon, comprising:

• a substrate having a lower surface and an upper surface;
• multiple lower electrodes formed on the lower surface of the substrate;
• multiple upper electrodes formed on the upper surface of the substrate, vertically aligned with the respective lower electrodes, and electrically connected to the respective lower electrodes;
• a first insulation layer formed on the upper surface of the substrate and having at least one first connection member electrically connected to corresponding upper electrodes;
• a conductor layer formed on the first insulation layer and electrically connected to the at least one first connection member and the corresponding upper electrodes;
• multiple connection electrodes formed on the first insulation layer and vertically aligned with the respective upper electrodes, wherein a part of the multiple connection electrodes is electrically connected to the respective at least one first connection member for the conductor layer and the part of the multiple connection electrodes to be electrically connected to a part of the multiple upper electrodes through the respective at least one first connection member;
• a second insulation layer formed on the first insulation layer and having at least one second connection member electrically connected to the conductor layer;
• multiple surface electrodes formed on the second insulation layer and vertically aligned with the respective connection electrodes, wherein a part of the multiple surface electrodes is connected to the respective at least one second connection member;
• and
• multiple conductive cones formed on the second insulation layer, mounted on the respective surface electrodes, and adapted to electrically contact a PCB to be tested, wherein a part of the multiple conductive cones is electrically connected to the respective at least one second connection member, and a minimum distance is formed between each adjacent two of the multiple conductive cones without causing electrical contact with the respective surface electrodes underneath the multiple conductive cones;
• wherein a circuit layout of the conductor layer, the at least one first connection member and the at least one second connection member are formed to correspond to electrodes of the PCB to be tested.