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Showing papers on "Parasitic capacitance published in 1980"


Journal ArticleDOI
TL;DR: In this paper, a switched-capacitor filter is presented based on a pair of complementary integrators and has transfer functions independent of parasitic capacitances between any node and ground, and design equations are given for low-pass, bandpass, high-pass and notch biquads, as well as ladder simulation filters.
Abstract: New topologies for switched-capacitor filters are presented. The circuits are based on a pair of complementary integrators and have transfer functions independent of parasitic capacitances between any node and ground. Design equations are given for low-pass, bandpass, high-pass, and notch biquads, as well as ladder simulation filters. The ladder simulation filters are scaled for optimum dynamic range. Discrete prototypes of both cascade and ladder simulation filters are used to verify the theory.

188 citations


Journal ArticleDOI
TL;DR: In this article, two methods have been developed for analyzing MOS transients: analytical and quasi-static approximation, which is useful when the stray capacitance dominates MOS transient performance; and numericaf, which uses a new boundary value method which can be applied over a wide range of operating speeds.
Abstract: Two methods have been developed for analyzing MOS transients. One method is analytical and uses the quasi-static approximation. It is useful when the stray capacitance dominates MOS transient performance. The second method is numericaf and uses a new boundary value method which can be applied over a wide range of operating speeds. This method includes secondary effects and nonuniform doping. The validity and Iimits for both methods are verified by comparison with measurements. Transit-time delay and charge-pumping effects are also analyzed using the numerical method. Examples of short-channel behavior of MOS devices are included.

144 citations


Journal ArticleDOI
TL;DR: In this paper, two methods have been developed for analyzing MOS transients: analytical and quasi-static approximation, and numerical and a new boundary value method which can be applied over a wide range of operating speeds.
Abstract: Two methods have been developed for analyzing MOS transients. One method is analytical and uses the quasi-static approximation. It is useful when the stray capacitance dominates MOS transient performance. The second method is numerical and uses a new boundary value method which can be applied over a wide range of operating speeds. This method includes secondary effects and nonuniform doping, The validity and limits for both methods are verified by comparison with measurements. Transit-time delay and charge-pumping effects are also analyzed using the numerical method. Examples of short-channel behavior of MOS devices are included.

125 citations


Patent
08 Apr 1980
TL;DR: In this article, a gas discharge tube having a known breakdown voltage and a known capacitance is coupled between the first and second conductors of the mounting device to produce a characteristic impedance which is generally equal to the characteristic impedance of the radio frequency signal cable.
Abstract: A connector is provided for the suppression of electromagnetic impulses traveling a radio frequency cable. Paired first and second electrical connectors are provided for being operatively interposed along the signal cable. A spacer or mounting device is provided for electrically coupling the primary conductors and secondary conductors of one connector to their counterparts in the other paired connector. A gas discharge tube having a known breakdown voltage and a known capacitance is electrically and mechanically coupled between the first and second conductors of the mounting device. The inductance of the elements comprising the mounting device are determined such that this inductance interacts with the capacitance of the gas discharge tube and other stray capacitance of the combination thereof in order to produce a characteristic impedance which is generally equal to the characteristic impedance of the radio frequency signal cable, whereby the supressor will dissipate electrical surges while representing a low standing wave ratio to radio frequency energy being transmitted along the radio frequency signal cable.

109 citations


Patent
23 Jan 1980
TL;DR: In this article, a user, touch actuable switch panel of the capacitive type that includes one or more capacitive switches, each switch including at least two capacitive plate elements formed on a dielectric panel is considered.
Abstract: A user, touch actuable switch panel of the capacitive type that includes one or more touch actuable capacitive switches, each switch including at least two capacitive plate elements formed on a dielectric panel. Conductive paths formed on the dielectric panel interconnect the capacitive plate elements to a source for applying signals to the capacitive plate elements forming said capacitive switches and sensing a resulting change in signal level when a selected switch is actuated by the user. Trim tabs formed on the dielectric panel are provided to balance the effect of stray capacitance between the conductive paths and the capacitive plate elements to maintain the level of change of signal at a determined value upon the actuation of each of said one or more capacitive switches.

103 citations


Patent
03 Apr 1980
TL;DR: In this paper, the relative position of two objects by variation of capacitance is measured by a capacitive detector of the differential type which has at least two first electrodes adapted to be mechanically connected to one of the objects and at least a second electrode adapted to being mechanically connected with the other object and forming with the first electrodes two capacitances.
Abstract: A device for measuring the relative position of two objects by variation of capacitance. The device comprises a capacitive detector of the differential type which has at least two first electrodes adapted to be mechanically connected to one of the objects and at least a second electrode adapted to be mechanically connected to the other object and forming with the first electrodes two capacitances which vary as a function of the relative position of the objects. These two capacitances are in a ratio which is only a function of this relative position. There is provided a circuit for determining the values of these capacitances. The measuring device further comprises switching means for selectively connecting said capacitances to the input of said value determining circuit so as to measure successively said capacitances and also the parasitic capacitance inherent in the measuring system.

70 citations


Journal ArticleDOI
TL;DR: In this article, a two-dimensional spiral wound air-core inductors have been investigated for dc-to-dc conversion and closed-form expressions for the total inductance and the resistance are given.
Abstract: The trend toward size reduction of power-conditioning circuitry is increasing the use of higher switching frequencies (in the megahertz range) for dc-to-dc conversion. For power magnetic components this is requiring novel designs of energy-storage inductors. An investigation is reported of two-dimensional spiral wound air-core inductors. These inductors have the potential advantages of being printable as a thick- or thin-film circuit element and, therefore, inexpensive to manufacture. Via a simplifying approximation, one can reduce a formidable mathematical problem to one in which closedform expressions can be written for the total inductance and the resistance. Our approximate expression for the resistance is meant to account for the skin effect exactly and for the proximity effect in an average way. A comparison is presented between the predicted and measured value of impedance as a function of frequency. Implications of these results and of modeling the effects of parasitic capacitance are discussed in the context of determining an optimized geometry and operating frequency.

43 citations


Patent
06 Oct 1980
TL;DR: In this article, a tunable delay circuit (30) delays the actuation of the sense amplifier, where a plurality of impedance sections with associated parasitic capacitance are bypassed by switching devices such as MOS transistors.
Abstract: A semiconductor memory having an address buffer (10), row decoder (12), word lines (16), bit line (20) and sense amplifier (22) for accessing individual memory cells in an array of memory cells. In order to emulate worst case delays experienced in the word lines in accessing the last cells in the rows in order to prevent the sense amplifiers (22) from reading the bit lines (20) too soon, a tunable delay circuit (30) delays actuation of the sense amplifier. This circuit is divided into a plurality of impedance section with associated parasitic capacitance where groups of sections are bypassed by switching devices such as MOS transistors. The delay of a signal propagating through this tunable delay circuit can be varied by bypassing varying numbers of the sections with the switching devices.

39 citations


Patent
02 Oct 1980
TL;DR: In this article, a closed loop air/fuel ratio control utilizes a heated zirconia sensor, the sensor having an internal parasitic capacitance and being characterized by a leakage current path between the heater element and the capacitance.
Abstract: An internal combustion engine with a closed loop air/fuel ratio control utilizes a heated zirconia sensor, the sensor including a resistance heater element connected to receive electric current from the vehicle battery, the sensor having an internal parasitic capacitance and being characterized by a leakage current path between the heater element and the capacitance. The sensor output voltage is sampled by the closed loop control periodically and current is supplied to the heater element only during periods which end a predetermined time before each such sampling so that any charge on the capacitance may discharge before it affects the sampled voltage. Within each period, the current may be duty cycle modulated in response to vehicle battery voltage to maintain a constant average power to the heater element when heat is required.

33 citations


Patent
19 Sep 1980
TL;DR: An electric blanket control effective to deactivate power to the blanket's resistance wire heating circuit, the control having a capacitance detector constructed and adapted to respond to differences in the capacitance of the heating circuit attributable to the presence or absence of the user under the heating wire of the blanket.
Abstract: An electric blanket control effective to deactivate power to the blanket's resistance wire heating circuit, the control having a capacitance detector constructed and adapted to respond to differences in the capacitance of the heating circuit attributable to the presence or absence of the user under the heating wire of the blanket, and a switch responsive to the detector adapted to interrupt power to the heating circuit when the capacitance value of the heating circuit indicates the absence of the user.

30 citations


Patent
09 Jan 1980
TL;DR: In this article, the body capacitance was added to the circuit to actuate the switching circuit in the presence of only stray capacitance (C E ) so that the circuit remains unactuated.
Abstract: The casing (12A) of a hand-held instrument (12) provides a contact surface for a capacitive switching circuit for energizing a controlled device (63). The switching circuit and device are remote from the contact area. The switching circuit includes an input circuit (80) incorporating the body capacitance (C B ) and a variable capacitor (81) which is adjusted to balance the circuit in the presence of only stray capacitance (C E ) without body capacitance so that the switching circuit remains unactuated. The addition of body capacitance will actuate the switching circuit. In the illustrated embodiment, the input circuit (80) is energized by a periodic signal. An output signal is coupled from the switching circuit to the controlled device through a delay off circuit (88) which has a delay time longer than the period of the periodic signal so that if contact with the instrument is lost momentarily, there is no interruption in the controlled function. This is particularly advantageous in the case of a medical device or dental handpiece where light from a high intensity source is coupled back to the instrument for illuminating the work area.

Journal ArticleDOI
TL;DR: In this paper, a planar integrated circuit with deep-depletion plasma-grown native oxide gate GaAs MOSFET's was fabricated using conventional photolithography to assess the speed-power performance in digital applications.
Abstract: Selective and multiple ion implantations directly into a semi-insulating GaAs substrate were utilized to fabricate planar integrated circuits with deep-depletion plasma-grown native oxide gate GaAs MOSFET's. 1.2-µm gate 27-stage enhancement/depletion (E/D) type ring oscillators, with the circuit optimized to reduce parasitic capacitance, were fabricated (using conventional photolithography) to assess the speed-power performance in digital applications. A minimum propagation delay of 72 ps with a power-delay product of 139 fJ was obtained, making these devices the fastest among current GaAs and Si logic fabricated by conventional photolithography. A minimum power-delay product of 36 fJ with a propagation delay of 157 ps was obtained. The power-delay product is comparable with that of 1.2-µm gate GaAs E-MESFET logic, and the speed is more than twice as great. This paper includes a comparison of the theoretical cut off frequency of MESFET and MOSFET logic devices operating in depletion mode. Results indicate that MOSFET logic has superior potential for high-speed operation.

Journal ArticleDOI
TL;DR: In this article, two new circuits for the accurate measurement of specimen capacitance and resistive loss are described, and the capacitance measurements are unaffected by the specimen resistance when the parallel resistance is greater than 30?.
Abstract: Two new circuits for the accurate measurement of specimen capacitance and resistive loss are described. The capacitance measurements are unaffected by the specimen resistance when the parallel resistance is greater than 30 ?. The practicality of the circuit is enhanced by its use of coaxial cable to provide both connection to the sample and the inductance required for circuit operation. An important characteristic of the circuit is its ability to measure capacitance and resistance of very high loss specimens accurately.

Journal ArticleDOI
TL;DR: In this paper, the effects of large signals in modifying the effective varactor capacitance and hyperabrupt doping profile were analyzed for series-tuned oscillators realized with simple configurations of BJT's or FET's in chip, integrated or monolithic form with low parasitics.
Abstract: Varactor properties and a particular hyperabrupt doping profile are identified which can provide wide-band tuning linearity for an important class of microwave oscillators. The results are most appropiate for series-tuned oscillators realized with simple configurations of BJT's or FET's in chip, integrated, or monolithic form with low parasitics. The derivation for the doping profile is presented and includes the effects of large signals in modifying the effective varactor capacitance. In addition, breakdown conditions and the level and variation in series resistance are included. When the results are applied to BJT and FET oscillator circuits with measured large-signal properties, the profiles obtained predict excelent linearity for the FET over a 7-12-GHz frecuency range and fair linearity for the BJT circuit from 2 to 4 GHz. The profiles are reasonable and should be realizable with existing varactor fabrication technology.

Proceedings ArticleDOI
Tak H. Ning1, R.D. Isaac, P.M. Solomon, Denny D. Tang, H.N. Yu 
01 Jan 1980

Patent
William R. Dougherty1
14 May 1980
TL;DR: In this paper, the authors present an apparatus for measuring and storing a value related to an unwetted capacitance of a capacitive sensor, the stored value being available for use in liquid measurements.
Abstract: The present invention is part of a liquid gaging system and comprises an apparatus for measuring and storing a value related to an unwetted capacitance of a capacitive sensor, the stored value being available for use in liquid measurements. Included is a capacitive sensor for mounting in a tank, the sensor having an unwetted capacitance variable in dependence on manufacturing tolerances. The sensor capacitance is also related to stray capacitance in the system. The invention further includes apparatus for measuring the sensor unwetted capacitance including the sensor capacitance contributed by the stray capacitance in the system. The apparatus for measuring is connected to the sensor. The invention also comprises apparatus for storing a value related to the sensor unwetted capacitance measured by the apparatus for measuring, the apparatus for storing being connected to the apparatus for measuring.

Proceedings ArticleDOI
H. Iwai1, S. Kohyama
01 Jan 1980
TL;DR: In this paper, a precise capacitance measurement technique is described, based on a principle of capacitively devided a.c. voltage measurement, where reference and test capacitors are connected in series, and intermidiate node signal is monitored by on chip linear sense amplifier.
Abstract: A precise capacitance measurement technique is described. This technique is based on a principle of capacitively devided a.c. voltage measurement. In test devices, reference and test capacitors are connected in series, and intermidiate node signal is monitored by on chip linear sense amplifier. Utilizing the technique, various capacitances were measured, and quantitativery compared with a two dimensional numerical analysis. The results indicate that the technique is practical and accurate for evaluating capacitive elements in VLSI's.

Patent
Itsuo Akazawa1
04 Feb 1980
TL;DR: In this article, a variable capacitance transistor is used to vary the oscillation frequency of an oscillating transistor in an FM modulation circuit. But the transistor has resistors connected between the emitter and base and between the collector and base, respectively.
Abstract: In an FM modulation circuit, a variable capacitance circuit employs a transistor as a variable capacitance element. The transistor has resistors connected between the emitter and base thereof and between the collector and base thereof, respectively, and is connected under the unbiased state to an oscillating transistor of an oscillation circuit constituting the FM modulation circuit. In correspondence with an input signal applied across the emitter and collector of the variable capacitance transistor, the emitter--collector capacitance of this transistor is varied to vary the oscillation frequency of the oscillation circuit.

Patent
03 Nov 1980
TL;DR: In this article, the RC time constants of the input and the feedback circuits are made to be approximately equal at the time of pulse input in order to insure an output pulse flat base line without undershoot or overshoot.
Abstract: An amplifier circuit having an input circuit of resistance and capacitance which is a.c. coupled to a source of pulses, and a feedback circuit of resistance and capacitance. The RC time constants of the input and the feedback circuits are made to be approximately equal at the time of pulse input in order to insure an output pulse flat base line without undershoot or overshoot.

Patent
28 Feb 1980
TL;DR: In this article, a simple effective capacitance measurement circuit was developed for analog computation as an inverting integrator, where the feedback capacitor is a measurement capacitor and an a.c. voltage is applied to the amplifier and the inverting input via the ohmic impedance.
Abstract: A circuit having a capacitor (1) in the feedback path of an operational amplifier (2) which has an ohmic impedance (3) connected to its inverting input is applicable to analogue computation as an inverting integrator. The circuit is developed for use as a simple effective capacitance measurement circuit. The feedback capacitor (1) is a measurement capacitor. An a.c. voltage is applied to the amplifier (2) inverting input via the ohmic impedance (3) and a measurement instrument (22) is connected to the output of the amplifier. The capacitance measurement takes place practically independently of the connector capacitance magnitudes and variations. The arrangement enables dynamic capacitance variations to be measured. The earthing capacitance effect is negligible if an operational amplifier closely approximating the ideal is used. Connector capacitance compensation circuits can be incorporated.

Journal ArticleDOI
TL;DR: In this paper, the PEE (Polycrystalline electrodes with epitaxy) transistor was developed especially with respect to base and collector geometry for high speed bipolar LSI.
Abstract: A new transistor structure for high speed bipolar LSI, named PEE (Polycrystalline Electrode with Epitaxy) transistor, has been developed especially with respect to base and collector geometry. The basic features of the new structure are ; (1) polycrystalline silicon electrodes for a base and a collector and also polycrystalline silicon resistors, and (2) two-step oxide isolation which enables the bottom side isolation of an extrinsic base to the collector. The new structure can minimize parasitic capacitance, for instance, CTC can be reduced to about half of the conventional oxide isolated structure. This results in a high cutoff frequency of 6.0 GHz. Gate delay time and power-delay product measured with five-stage ECL ring oscillators ranged from 0.74 nsec, 2.8 pJ to 1.3 nsec, 1.8 pJ, and the performance was improved approximately 20% compared with the conventional devices.

Patent
28 Jul 1980
TL;DR: In this paper, a pulse generator for generating pulses having predetermined slopes is described, comprising a capacitor that can be charged and discharged through predetermined current sources, a switching device for connecting and disconnecting the current sources and a step function signal source for controlling the switching device.
Abstract: A pulse generator for generating pulses having predetermined slopes is disclosed, comprising a capacitor that can be charged and discharged through predetermined current sources, a switching device for connecting and disconnecting the current sources and a step function signal source for controlling the switching device. The capacitance of the capacitor is in the range of the stray capacitance of the switching device. A fraction of the output signal of the step function signal source is superimposed in oppposite phase upon the output signal of the capacitor so as to compensate the voltage surge in the output signal of the capacitor resulting from the voltage divider formed by the stray capacitance of the switching device and the capacitor.

Journal ArticleDOI
TL;DR: In this paper, the equivalent circuits for switched-capacitor (SC) networks including recharging devices are derived, and the equivalent time-invariant network is split up into a frequency dependent impedance network and a purely (negative) resistive network which corresponds directly to the capacitor network of the SC-filter.
Abstract: Equivalent circuits for switched-capacitor (SC) networks including recharging devices are derived. Parasitic effects, like stray capacitances and nonideal op amps, are taken into account. As a result, the equivalent time-invariant network is split up into a frequency dependent impedance network and a purely (negative) resistive network which corresponds directly to the capacitor network of the SC-filter and allows for the loss compensation achieved by the recharging switching devices. In general, these two parts of the equivalent network are coupled via generalized impedance converters (GIC's).

Proceedings ArticleDOI
H. Iwai1, K. Taniguchi, M. Konaka, S. Maeda, Yoshio Nishi 
01 Jan 1980
TL;DR: In this paper, the effects of field channel stop ion implantation on the narrow channel effect, the field MOS threshold voltage and the junction breakdown voltage are also discussed toward optimization of coplanar process parameters.
Abstract: Two dimensional nature of diffused line capacitance in the coplanar MOS LSI structure is investigated delineating importance of the side wall capacitance with decreasing feature size of devices. The effects of field channel stop ion implantation on the narrow channel effect, the field MOS threshold voltage and the junction breakdown voltage are also discussed toward optimization of coplanar process parameters.

Patent
Joachim Goerth1
10 Jan 1980
TL;DR: In this article, a semiconductor element having a MOS-capacitor between a zone provided in an epitaxial layer on a substrate and a conductive layer on an insulating layer above the zone is utilized in a structure comprising a tunable oscillator having a differential amplifier, a current distributor controlled by a control voltage, a phase shifting element comprising the MOS capacitance and a feedback path present between the phase shift element and an input of the differential amplifier.
Abstract: A semiconductor element having a MOS-capacitor between a zone provided in an epitaxial layer on a substrate and a conductive layer on an insulating layer above the zone is utilized in a structure comprising a tunable oscillator having a differential amplifier, a current distributor controlled by a control voltage, a phase shifting element comprising the MOS-capacitor and a feedback path present between the phase shifting element and an input of the differential amplifier. The feedback path comprises a quartz oscillator and an emitter-follower transistor. The stray capacitance between the zone and a substrate of the opposite conductivity type is considerably reduced by a further zone of the opposite conductivity type which is applied to a fixed potential through a connection electrode. This connection point is for the supply voltage of the circuit, while the further zone of the first conductivity type is connected parallel to the emitter-base current path of the emitter-follower transistor.

Patent
Suzuki Toshiro1
17 Jun 1980
TL;DR: In this paper, a hybrid integrated impedance converter circuit comprising a frequency dependent negative resistance circuit, in which two operational amplifiers are included, is presented, with a negative feedback capacitor being formed by a stray capacitance which arises between conductors connected to the output and inverting input terminals.
Abstract: A hybrid integrated impedance converter circuit comprising a frequency dependent negative resistance circuit, in which two operational amplifiers are included Each of the two operational amplifiers has an output terminal and an inverting input terminal, with a negative feedback capacitor being connected between these terminals The negative feedback capacitor is formed by a stray capacitance which arises between conductors connected to the output and inverting input terminals, which conductors are placed in close proximity to each other

Patent
05 Dec 1980
TL;DR: In this paper, a bipolar signal transmitter having a function outputting the bipolar signals when a PCM signal is inputted, in the form of existing and spare systems, is provided to avoid momentary interruption or overlapping of bipolar signals at switching to a spare system.
Abstract: PURPOSE:To avoid momentary interruption or overlapping of bipolar signals at switching to a spare system, by providing a bipolar signal transmitter having a function outputting the bipolar signals when a PCM signal is inputted, in the form of existing and spare systems. CONSTITUTION:When an existing set 11 is in failure, the switching instruction information of existing and spare sets is applied to a control circuit 31 to apply a switching signal to the control circuit 31 and a hysteresis circuit 32. After the hysteresis circuit 32 turns on a contact SW2 of a relay 22 first, the off-state of an electronic switch 16 and the on-state of an electronic switch 26 are controlled at the same time and the contact of a relay 12 is made to off-state. The operating time of the electronic switches 16, 26 is several ns-several tens of ns, and no short break is caused even to high-speed bipolar signals. Since waveform is deteriorated due to stray capacitance when an output transformer 15 is connected to an output terminal 43, complete disconnection is made with the relay 12.

Patent
30 Jun 1980
TL;DR: In this paper, a two-terminal bilinear resistor with a negative capacitance of value -C/2 and a positive capacitance C/2 is proposed for simulating a floating resistor having a resistance R=T/C across the terminals, which satifies the Bilinear transformation s=(2(z-1/T)z+1).
Abstract: A two terminal circuit comprising a capacitive element (with a negative capacitance of value -C/2) connected between the terminals, and an integrated capacitor (with a positive capacitance C) having one and other sides thereof alternately or periodically connected to associated sides of the element and to ground for simulating a floating bilinear resistor having a resistance R=T/C across the terminals which satifies the bilinear transformation s=(2(z-1/T)z+1). This circuit is insensitive to both top and bottom plate parasitic capacitance effects assocated with the capacitance when one terminal is connected to a voltage source and the other to a virtual ground point on the input to an operational amplifier. In alternate embodiments, the circuit simulates a grounded bilinear resistor when only one of the terminals is connected to ground, and when one terminal and one side of the capacitor are grounded. In many applications the negative capacitive element may be absorbed by a positive capacitor of larger capacitance that is connected in parallel with it in a switched capacitor circuit.

Patent
13 Feb 1980
TL;DR: In this paper, the authors propose an approximate approach to reduce the number of resistances and switches needed for compensation, yet provide minimal error. But, their approach is limited to the frequency of operation of the active filter.
Abstract: Method and apparatus for compensation of switched resistance active filterso maintain a relatively constant Q and voltage gain by switching additional resistors in and out of the filter circuit. Solid state circuitry provides signals for activating switches to switch the compensating resistances as the operating frequency of the filter is altered. Compensation depends essentially on the number of open switches in the frequency selecting resistance array rather than on frequency of operation. An approximate approach reduces the number of resistances and switches needed for compensation, yet provides minimal error.

Patent
Mitsuo Higuchi1
26 Nov 1980
TL;DR: An oscillation circuit for providing oscillation frequencies which vary in response to the intensity of incident light rays is described in this article, where the circuit comprises a capacitance for storing charges and a charging circuit.
Abstract: An oscillation circuit for providing oscillation frequencies which vary in response to the intensity of incident light rays. The circuit comprises a capacitance for storing charges and a charging circuit; said stored charges being decreased in response to an increase in the intensity of light rays incident on the capacitance; the charging circuit connected to the output of the oscillation circuit; the charging circuit being adapted to charge the capacitance. The oscillation circuit, when adapted to a bootstrap circuit in an EPROM erasable by means of ultraviolet rays, improves the write-in efficiency thereof.