Logic circuits inverter

Fig. 3. Experimental demonstration of one-, two- and three-transistor logic circuits with CNTFETs [41]. Output voltages as a function of the input voltage are given for (A) an inverter, (B) a NOR gate, (C) a static random access memory cell (SRAM) and (D) a ring oscillator.

Concerning a logic circuit to operate this switching device, Matsumura and Nara (1982) studied inverters that are composed of an enhancement -channel driver TFT and p-channel load TFT. Step-shaped transfer characteristics have been realized. However, the operating frequency is not sufficient at the present time. 

Fig. 13.4 Scheme of logic circuit of the hardware-controlled titrator designed by Hieftje et al. Ci and C2 are comparators Gi-Ge are gates I1 and I2 are inverters Mi and M2 denote monostables adjustable from 100 ps to 1 ms and T1 denotes a 2N3439 transistor. (Reproduced from [57] with permission of the American Chemical Society),... 

In the standard cell approach, the IC designer selects from a library of predefined logic circuits or cells to build the desired circuit. In addition to the basic gates, the cell library usually includes more complex logic circuits such as exclusive-OR, AND-OR-INVERT, flip-flops, adders, read only memory (ROM), etc. 

FIGURE 8.33 Elementary CMOS logic circuit (a) complementary MOS inverter stage, (b) two-input CMOS NOR gate. 

IBM researchers have created what they say is the world s first logicperforming computer circuit within a single molecule. This development can lead into a new class of smaller and faster computers that consume less power than today s machines. They made a voltage inverter. It is one of three fundamental logic circuits that are the basis for today s computers from a carbon nanotube, a tube-shaped molecule of carbon atoms 100,000 times thinner than a human hair. 

Current only flows in the CMOS inverter when the load capacitor is being charged or discharged. No current flows to maintain a logic level (0 0 V, 1 5 V). Because power is dissipated only when current flows, the amount of power dissipation in a CMOS circuit is proportional to circuit... 

Bruckenstein [2] introduced a digital oscillator which comprised two TTL inverters with a positive feedback through the crystal. The circuit is very stable and can be interfaced directly with TTL or CMOS logic obtain-... 

An alternative application of coupled inverters is to place an even number (say, 2) together and create a bistable logic reprogrammable memory circuit. An example SRAM formed in this way is shown in Fig. D.5 [145]. 

Fig. 9.8. (Left) the circuit of a logic inverter including a depletion mode transistor and (right) its associated input-output characteristics...

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