Negative impedance converter

About: Negative impedance converter is a research topic. Over the lifetime, 5801 publications have been published within this topic receiving 87636 citations.

Electromechanical transducer-coupled mechanical structure with negative capacitance compensation circuit

Abstract: Arrangements are disclosed for substantially reducing the effect of the inherent transducer capacitance in a transducer-coupled electromechanical system which is subject to vibrational movement. Electrical circuitry is coupled across the transducer output to provide a negative capacitance having a magnitude substantially the same as that of the inherent transducer capacitance, thereby substantially nullifying the inherent transducer capacitance and enabling improved damping (including low-noise damping) to be achieved.

Criteria for stability in bistable electrical devices with S‐ or Z‐shaped current voltage characteristic

Abstract: Electronic devices exhibiting bistability in the current‐voltage characteristics are considered from a unified viewpoint. We obtain simple relations for the stability of the different branches in the current‐voltage characteristics. Criteria for oscillatory instabilities are discussed, and special conclusions for elements with S‐ or Z‐shaped characteristics are drawn. The stabilization of the middle branch of the double‐barrier resonant‐tunneling diode in a circuit with effectively negative capacitance and negative resistance is derived in a simple way.

Examination of the Possibility of Negative Capacitance Using Ferroelectric Materials in Solid State Electronic Devices

Abstract: We show here, using fundamental energy storage relationships for capacitors, that there are severe constraints upon what can be realized utilizing ferroelectric materials as FET dielectrics. A basic equation governing all small signal behavior is derived, a negative capacitance quality factor is defined based upon it, and thousands of carefully measured devices are evaluated. We show that no instance of negative capacitance occurs within our huge database. Furthermore, we demonstrate that highly nonlinear biasing behavior in a series stack could be misinterpreted as giving a negative capacitance.

Isolated bidirectional DC-DC converter

Abstract: The DC-DC converter connects a first and a second switching circuit for converting power mutually between direct current and alternating current respectively to a first DC power source and a second DC power source and has a transformer between the AC terminals thereof Here, between the AC terminals of the second switching circuit and the negative pole terminal of the DC power source, a voltage clamp circuit composed of a series unit of switching devices with a reverse parallel diode and a clamp condenser is connected An isolated bidirectional DC-DC converter which prevents a reduction in a circulating current at time of buck and an occurrence of a surge voltage at time of voltage boost and realizes highly efficiency, low noise, and miniaturization is provided

A precise on-chip voltage generator for a gigascale DRAM with a negative word-line scheme

Abstract: A precise on-chip voltage generator for gigascale DRAM's with a negative word-line scheme is described. It combines a charge-pump regulator and a series-pass regulator, and it also includes a positive and negative offset voltage generator that uses a bandgap generator with a differential amplifier. The proposed circuit was experimentally evaluated with a test device fabricated using a 0.3-/spl mu/m process. The simulation results show that the series-pass regulator suppresses the noise on a word-line low voltage (negative) to below 30 mV for the word-line transient and V/sub BB/ bouncing. A dc-voltage error of less than 6% without trimming is confirmed for the positive and negative offset voltage generator through the test device. These results show that the described scheme can be used in future low-voltage gigascale DRAM's.