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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Device with step function variation of the capacitance is useful for voltage-controlled oscillator circuits and as a voltage-sensitive switch. Simplicity of construction makes the device suitable for large-scale integration, microelectronic circuits.
Thin film capacitive bolometer dependent on temperature sensitivity derived from electron trapping effects
Ripple filters for DC power supplies using reliable small capacitance capacitors suitable for spacecraft applications
Paired comparison tests of relative signals detected by capacitive and floating Langmuir probes in turbulent plasmas from 0.2 to 10MHz
Capacitance calculation for diffused p-n junction with exponential doping gradients
Capacitance study of solar cells and panels using sweep loading technique
Nuclear radiation effects on junction capacitance of silicon p-n diode
Capacitor field calculations for capacitive displacement measurement of open mesh structures such as radio telescopes and radar receivers
Absolute capacitance microcreep and dimensional stability measuring system
High impedance source with shunt capacitance, discussing periodic output measurement using operational amplifier
Capacitive and floating Langmuir probes paired comparison measurements of electrostatic potential fluctuations spectrum in steady state turbulent magnetically confined plasma
Capacitance voltage measurements on interface of pyrolytically deposited n-type silicon dioxide- InAs MOS diodes as function of admittance at room and 77 K temperatures
Paired comparison tests of relative signal detected by capacitive and floating Langmuir probes in steady state turbulent plasma confined in magnetic mirror geometry
The theory, applications, and possible structural designs of capacitive transducers are presented. Emphasis is placed on the circuits used in connection with the sensors, such as AM, FM, resonant circuits, mode circuits, direct current circuits, and special circuits. Some criteria for selection of a design or the purchase of a commercial device are given.
The advantages and disadvantages of different models of capacitive transducers and of various signal conditioning circuits are discussed with particular emphasis on the field of applications. A practical example of a design procedure is discussed.
The hardware phase of a digital capacitance measuring system is presented with the major emphasis placed on the electrical design and operation. Test results are included of the three units fabricated. The system's interface is applicable to existing requirements for the space shuttle vehicle.
Circuit multiplies capacitance without increasing overall circuit gain. In addition, circuit may be designed to include lag or lead/lag transfer function and independent gain adjustment.
A circuit using a differential amplifier multiplies the capacitance of a discrete interating capacitor by (r sub 1 + R sub 2)/R sub 2, where R sub 1 and R sub 2 are values of discrete resistor coupling an input signal e sub 1 of the amplifier inputs. The output e sub 0 of the amplifier is fed back and added to the signal coupled by the resistor R sub 2 to the amplifier through a resistor of value R sub 1. A discrete resistor R sub x may be connected in series for a lag filter, and a discrete resistor may be connected in series with the capacitor for a lead-lag filter. Voltage dividing resistors R sub a and R sub b may be included in the feedback circuit of the amplifier output e sub o to independently adjust the circuit gain e sub i/e sub o.