Showing papers on "Decoupling capacitor published in 1987"

Temperature responsive transmitter

Abstract: A temperature responsive transmitter is provided in which frequency varies linearly with temperature. The transmitter includes two identically biased transistors connected in parallel. A capacitor, which reflects into the common bases to generate negative resistance effectively in parallel with the capacitor, is connected to the common emitters. A crystal is effectively in parallel with the capacitor and the negative resistance. Oscillations occur if the magnitude of the absolute value of the negative resistance is less than the positive resistive impedance of the capacitor and the inductance of the crystal. The crystal has a large linear temperature coefficient and a resonant frequency which is substantially less than the gain-bandwidth product of the transistors to ensure that the crystal primarily determines the frequency of oscillation. A high-Q tank circuit having an inductor and a capacitor is connected to the common collectors to increase the collector current flow which in turn enhances the radiation of the oscillator frequency by the inductor.

Integrated dual charge pump power supply and RS-232 transmitter/receiver

Abstract: A monolithic integrated circuit containing an inverting/non-inverting voltage doubler charge pump circuit is disclosed for converting a unipolar supply voltage to a bipolar supply voltage of a greater magnitude. The unipolar input voltage is placed across a first external transfer capacitor by a first set of MOS switches during a first time period. The unipolar input voltage source is placed in series with the first transfer capacitor and this series combination of voltages is placed across a first external reservoir capacitor by a second set of MOS switches during a second time period. The voltage appearing across the first external reservoir capacitor is placed on a second transfer capacitor during the first time period by a third set of MOS switches. The voltage across the second transfer capacitor is placed into a second external reservoir capacitor with its polarity inverted by a fourth set of MOS switches during the second time period. A dual-collector lateral junction transistor, formed during the conventional CMOS processing steps used to fabricate the MOS switches, is connected as a voltage clamp between a ground potential and the two bipolar DC output lines of the power supply circuit to assure correct start-up conditions for the circuit. Gain reduction devices are placed in the semiconductor substrate to collect minority carriers which would otherwise be injected into inherent parasitic four layer PNPN junction devices created as a result of the architecture of the circuit, to prevent latch-up of the four layer devices. In a preferred embodiment, an RS-232 receiver and transmitter are contained on the same monolithic integrated circuit as the dual charge pump power supply.

High-frequency surgical instrument

Abstract: Described is a safety circuit for a high-frequency surgical instrument for the monopolar cutting and coagulating of biological tissue, where the neutral electrode is high-frequency-grounded through a capacitor. The safety circuit monitors the low-frequency leakage current which flows through the capacitor against the ground potential and interrupts the electric connection between this capacitor and ground potential immediately when the low-frequency leakage current exceeds an adjustable limiting value. Simultaneously, an optical signal and an acoustical signal are activated.

Flexible film chip carrier with decoupling capacitors

Abstract: An electronic packaging structure includes a second level electronic package having at least one opening formed therein and circuitry for electrical connection to a semiconductor chip. A circuitized polyimide film chip carrier includes at least one semiconductor chip mounted on one major surface thereof and at least one decoupling capacitor mounted on an opposite surface thereof. The decoupling capacitor is electrically coupled to input/output contacts of the semiconductor chip. The carrier is then mounted on the second level electronic package so that one semiconductor chip is positioned within a respective opening and the circuitry formed on the carrier is coupled to the circuitry formed on the second level package thereby interconnecting the semiconductor chip to the electronic package.

Decoupling capacitor for surface mounted leadless chip carriers, surface mounted leaded chip carriers and Pin Grid Array packages

Abstract: High frequency noise is decoupled from power supplied to Pin Grid Array (PGA), surface mounted leaded chip carrier and surface mounted leadless chip carrier packages by insertion of a decoupling capacitor between the PGA or leaded chip carrier package and printed circuit board; or by mounting the decoupling capacitor over a leadless chip carrier package. The decoupling capacitor comprises a multi layer capacitive element sandwiched between a pair of conductors and having a plurality of leads extending from each conductor. In accordance with the present invention, the decoupling capacitor is individually dimensioned and configured to fit under a PGA or leaded chip carrier package, or over a leadless chip carrier package; and correspond to the power and ground pin or lead configuration of that PGA, surface mounted leaded chip carrier and surface mounted leadless chip carrier package.

Disk drive head retract and motor braking method and apparatus

Abstract: One phase of a multi-phase spindle motor, normally used to rotate the disk of a disk drive system when power is on, is used to supply power to a capacitor storage circuit when power is lost (turned off or otherwise interrupted). The capacitor storage circuit provides the power to the retract circuit, which retracts the head. The combination of the generator effect of the phase and the capacitor storage circuit provides power to the retract circuit for a time clearly sufficient to reliably retract and lock the head regardless of the bias of the head prior to power loss. Simultaneously with one phase being used to retract the head, the other phases are shorted together to provide regenerative braking. FET drivers, normally used to drive the spindle motor when power is supplied, are used to short out the remaining phases to brake the motor when power is lost. In the preferred embodiment, the capacitor storage circuit is used as a line filter circuit when power is on. Therefore, the major circuit components used for retracting the head and braking the motor upon loss of power (capacitor storage circuit, motor windings, FET drivers) are all used for different purposes when power is on. This efficient use of the same circuitry for multiple purposes results in an efficient, reliable, compact, and relatively inexpensive approach for disk drive head retract and motor braking upon loss of power.

Anti-parallel capacitor

Abstract: A new and improved thin-film integrated capacitor having a low voltage coefficient and being comprised of two standard poly-metal capacitors which are connected in an anti-parallel fashion with the connecting poles of one of the poly-metal capacitors being connected to the reverse poles of the other poly-metal capacitor, thereby resulting in an integrated capacitor which has a constant voltage coefficient in a range approaching zero.

Low inductance capacitor

Abstract: A capacitor with a low parasitic inductance, which is particularly suited for use as a decoupling capacitor, that has a prismatic or polyhedral shape and includes a plurality of internal capacitor plates (10) positioned and separated by dielectric material (42). The improvement is that each plate is provided with a tab (16) that projects diagonally to a corner of the body with the edge of the tab exposed. A metal layer on the outside of the body electrically connects the plates in the desired sequence.

Telephone connector with bypass capacitor

Abstract: A modular jack for telephones in which bypass capacitors (26) have been connected to the leads (14) so as to bypass noise and other high frequency signals. End mounted ceramic capacitors (26) extend from the leads (14) to a ground plane (36) which is provided with flexible fingers (31) and which is connected to a suitable ground (51) so as to provide a grounding contact for the capacitors.

Decoupling capacitor and method of formation thereof

Abstract: A hermetically sealed and automatically insertable decoupling capacitor for use in conjunction with integrated circuit DIP inserter devices having a multi-layer ceramic capacitor chip provided with conductive electrodes on the top and bottom surfaces thereof sandwiched between suitable conductive strips and insulating layers and retained within an opening formed in an insulating strip by solder or conductive adhesive. The multi-layer ceramic capacitor further includes conductive end terminations having insulative caps thereon to prevent shorting.

Linearization of voltage-controlled oscillators using switched capacitor feedback

Abstract: The voltage-frequency characteristics of any voltage-controlled oscillator can be linearized using a simple circuit containing a switched capacitor The oscillation frequency becomes insensitive to power supply or temperature variations, and is determined only by the values of a capacitor, resistor, and the control voltage with respect to a reference voltage

High voltage capacitor

Abstract: A high voltage capacitor used for a low-pass filter circuit or the like in a magnetron oscillator circuit of an electronic cooking range includes in combination, a capacitor unit, a ground terminal into which the unit is inserted, two perforating conductors inserted through two through-bores extending in the capacitor unit, insulating casings encircling the capacitor unit on both sides of the ground terminal, insulating resin disposed in both of the insulating casings and surrounding the capacitor unit, an electrode at the outer periphery of the capacitor unit, and electrodes at the inner periphery of each through-bore which surround and are conductively coupled to each perforating conductor. When compared to a conventional high voltage capacitor, the present invention has a reduced number of components, is simple in construction, and is not subject to a lowering of the breakdown voltage durability caused by a heat cycle or the like.

Regulated rectifier d.c. power supply

Abstract: A control circuit for controlling a known active harmonic filter operating as a step-up converter in a power supply with sinusoidal network current input and a power factor of almost unity. The step-up converter comprises: a main rectifier, a storage inductance (LS), a cross-connected high-speed transistor (TQ), a diode (D1) and a power storage capacitor (CL). The high-speed transistor (TQ) is controlled by a first threshold switch (STc) whose input is controlled by a control capacitor (C12) coupled to receive a signal representative of instantaneous rectified d.c. output voltage (UE), instantaneous power output voltage (Uo) and a signal representative of the charge state of the inductance. The inductance charge signal is obtained from a voltage jump (ringing voltage) between the inductance and the diode (D1) by sensing a flank of an oscillation voltage occurring at the diode by a RC circuit (R8, C10), which triggers a second threshold switch (STa) to control charge reversal and recharge of the capacitor (C12), thus determining the time instants of operation of the first threshold switch to control the cross-connected electronic switch (TQ) to conduction, and hence re-storing of electrical energy in the inductance.

Dc to dc converter current pump.

Abstract: A DC to DC power converter designated a synchronous current pump (13) and operated in the preferred mode in synchronization with a discharge circuit (11) and using a capacitor (28) as the energy storage element, and in the preferred embodiment has in series with said capacitor the battery supply (10), an inductor (30), a diode (27a), and the primary winding (31a) of a transformer (31); and across said storage capacitor is an energy transfer FET switch (33) which is used for discharging said capacitor and transferring its stored energy to an output load capacitor (4) connected through a diode (32) to the secondary winding of said transformer In operation, the current pump supplies power efficiently and smoothly to a load discharge capacitor in synchronization with operation of the discharge circuit

Optimum Shunt Capacitor for Power Factor Correction at Busses with Lightly Distorted Voltage

Abstract: The goal of this paper is to determine the effect of time variation of system impedances and voltage harmonics on the value of optimum capacitor for power factor correction at busses with nonsinusoidal voltage. Two types of 24 hours time-variation of voltage harmonices and Thevenin impedance are assumed. The equivalent load impedance is also considered time variable and assumed to contain a large proportion of induction motors. The daily energy losses are computed and graphed in function of the shunt capacitance used for power factor correction. The results of this study indicate that in order to avoid resonances and to find the optimum capacitor the time variation of harmonics and system impedances must be known as precise as possible.

Power factor control with overvoltage and undervoltage override control in a capacitor control system for a distribution system

Abstract: A method and capacitor control apparatus for controlling the power factor and voltage on an electrical distribution line based on the power factor on the line subject to a voltage override control. Hysteresis above an undervoltage limit and below an overvoltage limit prevent undesired oscillation in switching the capacitor controls to and from the distribution line.

Transient and Harmonic Voltages Associated with Automated Capacitor Switching on Distribution Systems

Abstract: One of the functions proposed for distribution automation systems is automated capacitor switching to control power factor and voltage profile on feeder circuits. This is one of the functions being implemented as part of the Athens Automation and Control Experiment on the Athens Utilities Board (AUB) in Athens, Tennessee. A concern with automated capacitor switching is the increase in harmonic and transient voltages due to different capacitor configurations on the distribution system. A study was performed to evaluate the impact of the automated capacitor switching on the AUB distribution system. The study has identified problem areas, methods for determining the problem areas, and possible solutions. The substation capacitor banks were found to be the dominant factor in both the transient and harmonic repsonses of the distribution system. The harmonic response of the system is dominated by the parallel inductance/capacitance of the circuit comprised of the substation capacitor and equivalent source reactance at the substation. The transient analyses indicated that when the substation capacitor is energized, magnified transient voltages can occur at switched-in feeder capacitors. An evaluation of the effect of automated capacitor switching is necessary to properly design the automated capacitor switching schemes and the required arrester protection for any harmonic and/or transient overvoltage contingency.

Self-contained apparatus for de-icing aircraft surfaces using magnetic pulse energy

Abstract: A modular, electromagnetic de-icing system, useful for aircraft, each module being self-contained and including an actuator coil which has a surface configuration which is substantially the same as the shape of the aircraft surface to be de-iced. Each module further includes an electrolytic capacitor which, when discharged, produces a current pulse through the actuator coil, as well as a power supply connected directly to the aircraft-voltage supply for charging the electrolytic capacitor to a selected level, and an electronic switch for selectively connecting the capacitor to the coil when the voltage on the capacitor reaches a selected level. The current through the coil results in a magnetic force pulse which acts on the metal skin of the aircraft to debond and shatter the ice therefrom.

Method and apparatus for energizing a gaseous discharge lamp using switched energy storage capacitors

Abstract: A trigger circuit is coupled to a gas discharge lamp having anode and cathode terminals, a minimum anode voltage and a minimum holding voltage. The trigger circuit periodically transmits a trigger voltage pulse to the lamp to provide first stage ionization of the gas in the lamp. A power supply circuit charges a boost storage capacitor to a first voltage and an energy storage capacitor to a second voltage above the minimum holding but below the minimum anode voltage. The sum of the first and second voltages exceeds the lamp minimum anode voltage. A voltage controlled capacitor switching circuit includes input terminals coupled across the boost storage capacitor and across the energy storage capacitor and output terminals coupled to the anode and cathode terminals of the lamp. This switching circuit operates in a first state to apply a boost voltage exceeding the minimum anode voltage across the lamp anode and cathode terminals to allow energy to flow into the lamp after the first stage ionization of the lamp by the trigger circuit to provide second stage ionization of the lamp. The capacitor switching circuit switches into a second state after the boost voltage falls below the minimum anode voltage but before it falls below the minimum holding voltage to couple the energy storage capacitor across the lamp anode and cathode terminals to enable the energy storage capacitor to discharge additional energy into the lamp.

On the Choice of Phase-Balancer Capacitance for Induction Motors Fed from Single-Phase Supply

Abstract: This paper presents analytical evaluation for performance characteristics of a three phase induction motor when fed from a single phase supply. Starting as well as running of such motor are achieved by connecting a capacitor across two of stator phases in a way to act as a phase converter. Symmetrical components concept was employed in the analysis. The influence of capacitor value on motor characteristics is being investigated showing that there exists an optimum value of capacitor for a specific characteristic. Formulas are then derived for calculating these optimum values and recommendations are given for proper choice of capacitor rating and value.

Circuit for producing an alternating voltage

Abstract: A circuit is described for producing an alternating voltage in an electronic device which is remotely fed over a digital transmission path. By the pulses of a clock (8) two capacitors, C1, C2 are charged via a transistor (T1) and a transformer (10), one of them (C2) being discharged over a parallel resistor (R2). A coupling capacitor (CK) which is charged by the other capacitor (C1) is discharged alternately by the influence of the dischargeable capacitor (C2) over a transistor (T2).

Three plate integrated circuit capacitor

Abstract: A capacitor is described having a very low voltage coefficient of capacitance and a relatively large capacitance per unit area. A process is detailed for forming such a capacitor on an IC. The process is fully compatible with conventional IC processing and does not add substantially to the number of steps.

Parallel resonant single phase motor

Abstract: An improved electric motor is operated from a single phase alternating current power source (l0) and employs a start winding (l3) and a run winding (l4) connected in series A capacitor (26) is connected in parallel with the start winding (l3); and the inductance of the start winding and the capacitance of the capacitor are selected to form an LC resonant circuit at the operating frequency, thereby displacing the phase of the alternating current in the motor winding by 90° Some versions of the motor also have a starting capacitor connected in series with a starting switch in parallel with the first capacitor

Semiconductor integrated circuit device having an integrally formed bypass capacitor

Abstract: A semiconductor integrated circuit device according to the present invention comprising an electric circuit formed in a semiconductor substrate, said circuit including first and second nodes between which a potential difference is provided, a wiring of a large ground capacitance connected to the first node, and a bypass capacitor connected to the second node, said wiring and bypass capacitor being of an integral structure prepared by laminating an upper conductor film pattern connected to the second node via an insulating film on a lower conductor film pattern connected to the first node. A MIM-structure in which a wiring and a bypass capacitor are made integral is employed in the semiconductor integrated circuit device of the present invention, making it possible to eliminate the large area required for forming the independent bypass capacitor. Also, the ratio of the ground capacitance of the wiring to the capacitance of the bypass capacitor is constant regardless of the change in the length of the wiring.

Fault detector for detecting faults in a DC capacitor circuit

Abstract: A fault detector for detecting faults in a DC capacitor circuit connected to the DC buses of an inverter circuit using semiconductor device for converting direct current into alternating current to suppress the voltage pulsation and comprising a plurality of parallel-connected capacitor circuits each having a plurality of series-connected DC capacitors. The fault detector comprises a comparison means connected to the junctions of the series-connected DC capacitors to compare the respective potentials of the parallel-connected capacitor circuits, and detects the short-circuit and time-aging of the DC capacitors of the parallel-connected capacitor circuits rapidly on the basis of the output signal of the comparison means.

Capacitor circuit interruption.

Abstract: A circuit interrupter in electrical capacitors is activated by an interruption mechanism that moves an actuator (44) in response to a predetermined physical condition within the capacitor to cause electrical disconnection. The actuator has a range of motions through a limited number of stable positions and is mechanically pre-biased to move towards one of the stable positions when not already in one of the stable positions. Previously, pressure sensitive interrupters would be reconnected when the cover and terminals settled back due to pressure drop which could cause arcing. The present capacitor (12) is quickly and effectively disconnected when pressure builds up and stably remains in its popped up position to reduce the chance of reconnection. Capacitor terminals (18 and 20) are mounted on the actuator which is attached to a housing (54) by hinge regions (58) which provide a stable position upon build up of a pressure.

Decoupling capacitor for leadless surface mounted chip carrier

Abstract: High frequency noise is decoupled from power supplied to a surface mounted integrated circuit (IC) leadless chip carrier package by installation of a surface mounted decoupling capacitor over the IC chip carrier package and printed circuit board. The decoupling capacitor comprises a dielectric material sandwiched between a pair of conductors and having a plurality of leads extending from each conductor. In accordance with the present invention, the decoupling capacitor is individually dimensioned and configured to fit over a surface mounted integrated circuit (IC) leadless chip carrier package and correspond to the power and ground pin configuration of that package.

Circuit arrangement for limiting the switch-on current and for overvoltage protection of switched power supply apparatuses

Abstract: Circuit arrangement for limiting the switch-on current and for overvoltage protection of switched power supply apparatuses having an input-side storage capacitor (12), which forms a low-impedance voltage source for a power supply arrangement connected thereto. Such a power supply apparatus is intended to be provided with a circuit which not only limits the switch-on current but also ensures protection against overvoltages on the storage capacitor (12). This is achieved with the aid of a field-effect transistor (11) arranged between the supply voltage source (1) and the storage capacitor (12), which is not only controlled by an amplifier in the sense of current limiting but is also controlled by a delay member in the sense of delayed switching on. The power supply apparatus is particularly suitable for plug-in assemblies with voltage converters for supplying electrical telecommunications devices. … …

Transformerless current-limiting circuit

Abstract: Appliances such as fluorescent lamps and low-voltage DC motors can be operated from household AC without a transformer by employing a current-limiting circuit which is compact, lightweight, reliable, draws less energy, and has fewer power consuming components than do prior devices for driving those applicances. The current-limiting circuit has 4 rectifiers in a bridge circuit and a current-limiting capacitor which should be selected to match the load, a larger capacitor being necessary to supply a larger current. When used to drive a discharge lamp, the current-limiting circuit should also contain an inductive coil in series with the current-limiting capacitor. Otherwise there may be undue flicker. The inductive coil and capacitor together improve the power factor and therefore reduce the current drawn from the line without reducing the lamp output.

Remote control device having an energy source charged by a camera

Abstract: A remote control device has a transmitter provided with a transmission circuit for producing a remote control signal, a first capacitor of small capacity upon discharging to drive the transmission circuit, a second capacitor of large capacity upon discharging to charge the first capacitor, and a pair of terminals for charging the second capacitor from the outside of the transmitter.