Interposer block with retractable spring pin top cover plate

An integrated circuit chip package test system comprising:

• a daughter board having a top surface and a bottom surface, the top surface having a socket disposed thereon configured to receive a chip package for testing, the bottom surface having a plurality of electrical contact pads coupled to the socket via routing of the daughter board;
• a mother board having a top surface, the top surface of the mother board having a plurality of electrical contact pads;
• a pusher configured to urge a chip package towards the socket;
• and
• an interposer block disposed in between the mother board and the daughter board, the interposer block comprising:
• a main body having a top surface, a bottom surface, and a plurality of first spring pin receiving holes exiting through the top and bottom surfaces of the main body;
• a plurality of spring pins, each of spring pin disposed in a respective one of the plurality of spring pin receiving holes and contacting a contact pad of the plurality of contact pads of the mother board with a contact pad of the plurality of contact pads of the daughter board;
• a retainer plate coupled to the main body and capturing the spring pins within the plurality of spring pin receiving holes;
• a cover plate movably coupled to the main body, the cover plate having a plurality of spring pin clearance holes form therethrough that align with the plurality of spring pin receiving holes formed in the base plate;
• and
• a spring biasing the cover plate away from the main body to a position where the spring pins not an exposed through a top surface the cover plate, and where the cover plate is movable towards the main body to a position that exposes the spring pins through the top surface of the cover plate.

A method for testing a chip package, the method comprising:

• contacting a daughter board having a socket configured for testing a chip package to a top surface of a cover plate while ends of spring pins are recessed below the top surface, the cover plate part of an interposer block disposed coupled to a mother board of a test system;
• applying a force to the daughter board disposed against the top surface of the cover plate and moving the cover plate toward the mother board;
• engaging and displacing plungers of the spring pins as the cover plate moves toward the mother board;
• inserting a chip package in the socket;
• and
• testing the chip package utilizing signals transmitted from the mother board through the spring pins to the daughter board.