Patent ID: 7733721
Filing Date: 2010-06-08
Classification: G11C

Abstract:
1. A semiconductor testing device for testing a memory under test in which a page is made of a plurality of bits stored in a plurality of memory cells and data can be erased block by block, the block being made of a plurality of the pages, comprising: a pattern generator generating a test pattern; a pattern formatter shaping the test pattern and outputting a test signal; a comparator comparing a result signal with an expectation value, the result signal being output from the memory under test receiving the test signal; a bad block memory pre-storing pass/fail information of each of blocks in the memory under test, when a block to be tested is not a good one, outputting an instruction to inhibit an operation of outputting the test signal to the pattern formatter, and also outputting an instruction to inhibit an operation of comparing the result signal with the expectation value to the comparator; an address fail memory pre-storing pass/fail information of each of memory cells of the memory under test; a data compressor compressing data of pass/fail information in the address fail memory; a compression failure buffer memory storing data compressed by the data compressor; a good block register storing an address number of a good block prepared; and an address generator generating an address of a block to be compressed and sending the block address to the bad block memory, the address generator generating a column address and a row address of a page in the block address, when the block to be compressed which is indicated by the address of the block to be compressed is not a good one, wherein when the block to be compressed which is indicated by the address of the block to be compressed is not a good one, the address generator sends a column address and a row address of a page in the block to be compressed to the address fail memory and, when the block to be compressed is a good one, the good block register sends a address number of the good block to the compress failure buffer memory.