Sandisk Corporation

Sandisk Technologies Inc.

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Jian Feng Chen

Jeffrey W Lutze

Jun Wan

Kiran Ponnuru

Kirubakaran Periyannan

Loc Tu

Sridhar Yadala

Nyi Nyi Thein

Sowjanya Sunkavelli

Sowjanya Tungala

Sini Balakrishnan

Techniques and apparatuses are provided for detecting a short circuit between pins of an integrated circuit package. The tested pins can be adjacent or non-adjacent on the package. Various types of short circuits can be detected, including resistive, diode and capacitive short circuits. Additionally, short circuits of a single pin can be tested, including a short circuit to a power supply or to ground. The test circuit includes a current mirror, where the input path has a first path connected to a first pin and a parallel second path connected to a second pin. A comparator is connected to the output path of the current mirror. By controlling the on and off states of transistors in the first and second paths, and evaluating the voltage of the output path, the short circuits can be detected.

Circuit for detecting pin-to-pin leaks of an integrated circuit package

Consecutive logical block addresses (LBAs) are mapped to consecutive good blocks in a sequence of blocks in a memory device. For each bad block, a mapping process substitutes a next available good block. For a selected LBA, the mapping process determines a number X&#x3e;1 of bad blocks before, and including, a corresponding block in the sequence, a number Y of bad blocks in the X blocks after the corresponding block in the sequence, and maps the LBA to a block which is X+Y blocks after the corresponding block, or, if the block which is X+Y blocks after the corresponding block is a bad block, to a next good block. The mapping technique can be used for a sequence of blocks in a trimmed die, where a bad block register stores physical block addresses of the trimmed away blocks.

Mapping consecutive logical block addresses to consecutive good blocks in memory device

A memory management method includes identifying memory segments of a memory device. The method also includes identifying, for each memory segment, a number of faulty columns and determining a total number of faulty columns for the memory device. The method also includes, in response to a determination that the total number of faulty columns is greater than a threshold, identifying a memory segment having a highest number of faulty columns. The method also includes disabling the memory segment. Another method includes identifying, for each memory segment, a number of faulty memory blocks and determining a total number of faulty memory blocks. The method also includes, in response to a determination that the total number of faulty memory blocks is greater than a threshold, identifying a memory segment having a highest number of faulty memory blocks. The method also includes disabling the memory segment.

Systems and methods for capacity management of a memory system

Systems and methods in accordance with various embodiments can provide for comprehensive erase verification and defect detection in non-volatile semiconductor memory. In one embodiment, the results of erasing a group of storage elements is verified using a plurality of test conditions to better detect defective and/or insufficiently erased storage elements of the group. For example, the results of erasing a NAND string can be verified by testing charging of the string in a plurality of directions with the storage elements biased to turn on if in an erased state. If a string of storage elements passes a first test process or operation but fails a second test process or operation, the string can be determined to have failed the erase process and possibly be defective. By testing charging or conduction of the string in a plurality of directions, defects in any transistors of the string that are masked under one set of conditions may be exposed under a second set of bias conditions. For example, a string may pass an erase verification operation but then be read as including one or more programmed storage elements. Such a string can be defective and mapped out of the memory device.

Comprehensive erase verification for non-volatile memory

Systems for comprehensive erase verification in non-volatile memory

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San Jose, CA, United States of America

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