Office of Technology Transfer – University of Michigan

Multi-Bit Memory Read Method

Technology #5256

Resistive Memory Devices

Memory devices can be found in an ever-widening variety of products from computers to cameras, telephones and greeting cards. These memory devices comprise a large part of the growing $300 Billion semiconductor industry. Resistive memory devices, such as memristors, are a technology that could have fast switching capabilities like RAM, can store data indefinitely like flash memory, and have greater data density like hard drives. These devices could enable the ‘instant-on’ computer, which does not need to be booted from memory. Another advantage of this technology is its low-power requirements making them ideal for the power critical portable electronics segment. But current resistive memory devices require the use of reference resistors and in conjunction with voltage or current sources to detect the data stored.

Active Device Memory Read Method

Researchers in the Electrical Engineering and Computer Science department at the University of Michigan have develop a technology to read multi-bit memory devices using active devices. This technology uses active devices, such as diodes in configurations of series, parallel or a combination of both, to interpret the intermediate node voltage when a memory cell is selected and a voltage divider configuration between the memory cell and a bias resistor is obtained. This technology eliminates the need for reference resistors or sources and reduces the number of comparisons required to access the information in the memory cell.


  • Resistive memory devices such as memristor-based crossbar memory or any other resistive memory.


  • Eliminates the need for use of reference resistors or sources to store information in resistive memories.
  • Reduces the number of comparisons required to determine the data stored in a resistive memory cell.