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nanotimes News in Brief

11-01 :: December 2010 / January 2011

Fig. 2: Performance comparison between carbon nanotubes TFTs and other TFTs (Vertical Axis: mobility, Horizontal Axis: on /off ratio). © Aalto University / Professor Esko I. Kauppinen

*2 Flip-Flop: A basic logic element for today’s computers, a flip- flop is a circuit that has two stable states and can be used to store 1-bit state information.

*3 Synchronous sequential circuits: Two types of logic circuits exist in the digital circuit theory: combinational logic and sequential logic circuits. In the case of combinational logic circuits,

the output is a function only of the present input. In contrast, the output of sequential logic circuits de- pends not only on the present input but also on the history of the input. In other words, sequential logic has storage or memory functions. A synchronous sequential logic circuit is a sequential circuit synchro- nously operated based upon a clock signal. Almost all of today’s computers are composed of synchronous sequential circuits.