MRAM is an exciting opportunity; however even once you have working spin transistors there are other problems that must to be overcome before efficient MRAM can be produced. Ironically, one of the biggest problems is actually reading data from individual components of MRAM memory. The problem might be compared to trying to read a page of small text with a large magnifying glass, where you can only read one character at a time and the image is blurry with the characters on either side making it difficult to see the central character clearly.
The time taken to read a page of text this way makes the whole process unworkable, and it is the same with the âreader circuitryâ currently used with MRAM. One alternative would be to shrink the magnifying glass down to the size of an individual character, but this would make identifying each character difficult, and in the same way when we try to shrink the reader circuitry for MRAM we find it no longer works!
The second breakthrough discovery made in Oxford solves this problem! It is a new type of reader circuitry that is simple, accurate and works quickly. The value of each component of MRAM can be easily read without any interference from adjacent cells, and the reader circuitry itself can be miniaturised down to the same scale as the individual units of memory. It works like having a line of lenses across a page, each the same size as an individual character, and allowing an entire line of text to be read instantly before moving on to the next one!
Posted: Apr 26,2005 by Ron Mertens