New Transistor Model for Transition from Moderate to Strong Inversion and it's Applications for Design of CMOS Integrated Circuits with Fast Load and Supply Transients

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The practical side of the proposed research consists of recommendations for design of power management system blocks providing fast response for instant loads and fast power supply transients. The results will be applicable in the areas of advanced mobile computer terminals, medical and environmental sensors, and automotive instrumentation equipment.***A MOS transistor supplies the current depending on the condition which is called “inversion”. The weak and moderate inversions provide low currents, the strong inversion means operation at high currents. Moderate inversion is increasingly important region for low power analog circuit design. The definition of weak inversion says that a MOS transistor operates in weak inversion if the gate-source voltage is less than the threshold voltage. This means that for the gate-source voltage larger than the threshold voltage transistor starts to operate in moderate inversion. With further increase of the gate-source voltage the transistor enters strong inversion. Yet a simple model of the transistor drain current operating in moderate inversion was absent. Starting from the so-called “reconciliation” model the author of the proposal was able to provide this model which allows a better control for transition from moderate to strong inversion. ***The application of this model for design and investigation of wide range of circuits: amplifiers, voltage regulators and voltage references is the first project goal.***The modern tendency is to use integrated circuits in two distinct modes of operation. In the first mode the circuit is not loaded and should itself consume as less power as possible. In the second mode the circuit should provide power to the load. When the circuit does not supply power the transistors should operate in weak or moderate inversion. When the load is applied the transistors should start to work nearly instantly in strong inversion. This is especially valid for the circuits in power management electronic systems.***The proposed model is suitable for design of fast-responding circuits with practically instant load-on and load-off transients. Developing a complex of such circuits is the second project goal.***The fast response is usually required for both load and power transients. The design for fast power transients is not sufficiently investigated; the methods used for this purpose may even destroy the circuit operation when the supply voltage is applied. During the power transients, the undesirable operation points may occur. The mechanisms of their occurrences are not clear.***The third project goal is to profoundly investigate the occurrence of such points in these complex transients and develop methods for their elimination.***In summary, the proposal will develop and investigate, on the basis of new transistor model, the circuits with fast load and power transients, methods of their design, and give recommendations for their reliable operation.