Abstract: Two heat chambers are placed side-by-side. Heated air is blown upward through a first chamber and downward through a second heat chamber. An upper heating unit has a blower and heater that heat air exiting the first chamber and blows the heated air into the top of the second chamber. A lower heating unit has a blower and heater that heat air exiting the second chamber and blows the heated air into the top of the first chamber. Air is circulated in a loop through the two heat chambers by the two heating units. Inefficiencies from return pipes are eliminated by using the second chamber. The heated air is blown past memory modules under test in a heat chamber that has an insulated backplane. Pattern-generator cards outside the heat chamber exercise the memory modules and are cooled while memory modules in the heat chamber are heated.

Abstract: Two heat chambers are placed side-by-side. Heated air is blown upward through a first chamber and downward through a second heat chamber. An upper heating unit has a blower and heater that heat air exiting the first chamber and blows the heated air into the top of the second chamber. A lower heating unit has a blower and heater that heat air exiting the second chamber and blows the heated air into the top of the first chamber. Air is circulated in a loop through the two heat chambers by the two heating units. Inefficiencies from return pipes are eliminated by using the second chamber. The heated air is blown past memory modules under test in a heat chamber that has an insulated backplane. Pattern-generator cards outside the heat chamber exercise the memory modules and are cooled while memory modules in the heat chamber are heated.

Abstract: A memory module socket requires a reduced insertion force because a notch engager on a levered handle engages a notch on the memory module and applies downward pressure. The notch engager is forced downward as the levered handle pivots about an axis, causing the downward force to be applied to the notch on a memory module, forcing the memory module into a memory module socket on an extender card that plugs into a memory module socket on a personal computer motherboard. An ejector arm is pushed downward by the levered handle during removal. An ejector foot inside the memory module socket is pivoted upward around an ejector pivot when the ejector arm is pushed downward. The upward pivoting ejector foot pushes upward on the inserted edge of the memory module, forcing the memory module out of the memory module socket. Both ejection and insertion forces can be reduced.

Abstract: A levered handle has an elongated slot that allows the levered handle to both slide and pivot over a pivot axis. The levered handle is slid over the pivot axis to allow a notch engager to engage a notch on a memory module. Then the notch engager is forced downward as the levered handle pivots upward about the pivot axis, causing a downward force to be applied to the notch on the memory module. This forces the memory module into a memory module socket. The memory module socket requires a reduced insertion force because the notch engager on the levered handle engages the notch on the memory module and applies downward pressure. A levered handle without the elongated slot can slide along the pivot axis perpendicular to the memory module to engage the notch. Both ejection and insertion forces can be reduced.

Abstract: Memory modules with an extra dynamic-random-access memory (DRAM) chip for storing error-correction code (ECC) are tested on a personal computer (PC) motherboard tester using a cross-over extender card inserted into a memory module socket on the motherboard. ECC code generated on the motherboard is normally stored in the extra ECC DRAM chip, preventing test patterns such as checkerboards and walking-ones to be written directly to the ECC DRAM chip. During testing, the cross-over extender card routes signals from the motherboard for one of the data DRAM chips to the ECC DRAM chip, while the ECC code is routed to one of the data DRAM chips. The checkerboard or other test pattern is thus written and read from the ECC DRAM chip that normally stores the ECC code. The cross-over extender card can be hardwired, or can have a switch to allow normal operation or testing of the ECC DRAM chip.

Abstract: An environmental tester for memory modules has an environmental chamber for heating the memory modules being tested. One side of the chamber is a backplane. The memory modules are inserted into sockets on module motherboards, which are inserted into motherboard sockets on the backplane. On the other side of the backplane, card sockets receive pattern-generator cards that are outside the environmental chamber but electrically connected to the module motherboards through the backplane. The pattern-generator cards contain pattern-generators that generate address, data, and control signals that exercise the memory modules. The pattern-generator cards can be cooled while the memory modules in the environmental chamber are heated. Pattern-generator cards can be removed for repair and module motherboards can be removed for inserting new memory modules for testing.

Abstract: Hot air blown past memory modules under test in a heat chamber is improved. Hot air entering the chamber from an inlet pipe is split by a manifold and deflectors. Holes in the manifold allow for a relatively even air distribution within the chamber, minimizing temperature variations. Return air is collected by a heat-chamber bottom cover into a return pipe. A heating unit re-heats the return air and blows it into the inlet pipe. One side of the heat chamber is an insulated backplane. Memory modules are inserted into sockets on module motherboards, which are inserted into motherboard sockets on the backplane. On the other side of the backplane, card sockets receive pattern-generator cards outside the heat chamber but electrically connected to the module motherboards through the backplane. The pattern-generator cards exercise the memory modules. The pattern-generator cards are cooled while memory modules in the heat chamber are heated.

Abstract: A test socket for testing memory modules requires little or no insertion force. A base holds a funnel-shaped guide that guides the edge of the memory module into a desired position. Two housing halves are connected to the base by one or more hinges. The housing halves pivot around the hinges to open and close the test socket. Linkages, springs, or solenoids move the housing halves. Metal contact pads on flexible membranes are attached to each housing half and clamp onto contact pads on an inserted memory module when the housing halves are closed. Scooped vise clamps can be used to pinch together the ends of the housing halves to close the test socket. More test sockets can be fitted into a smaller pitch using the scooped vise clamps since the solenoids are along the longer axis of the test socket.

Abstract: An environmental tester for memory modules has an environmental chamber for heating the memory modules being tested. One side of the chamber is a backplane. The memory modules are inserted into sockets on module motherboards, which are inserted into motherboard sockets on the backplane. On the other side of the backplane, card sockets receive pattern-generator cards that are outside the environmental chamber but electrically connected to the module motherboards through the backplane. The pattern-generator cards contain pattern-generators that generate address, data, and control signals that exercise the memory modules. The pattern-generator cards can be cooled while the memory modules in the environmental chamber are heated. Pattern-generator cards can be removed for repair and module motherboards can be removed for inserting new memory modules for testing.

Abstract: A test system for testing memory modules uses vertically-mounted personal computer (PC) motherboards. Many test adaptor boards that contain test sockets for testing memory modules are mounted horizontally across a test bench. Each test adaptor board connects to a motherboard that tests the memory modules in the test sockets. The motherboard is mounted below and perpendicularly to the test adaptor board. The motherboard is modified to extend the memory bus to edge contact pads along an edge of the motherboard. An edge socket on the test adaptor board mates with the edge contact pads to make electrical connection. A robotic arm inserts a memory module into the test socket, allowing the vertically-mounted motherboard to execute programs to test the memory module. The density of vertically-mounted motherboards is 2-4 times higher than with horizontally-mounted motherboards.