Showing papers on "Decoupling capacitor published in 1982"

Forward converter switching at zero current.

Abstract: In a forward DC to DC converter (Fig. 4), switching losses are virtually eliminated by exploiting a controlled amount of leakage inductance of a transformer (10) in combination with a capacitor (15) to allow a switch (12) to turn on and off essentially at zero current. The combination of the secondary leakage inductance of the transformer (10) and the capacitor (15) defines an effective LC circuit having a characteristic time scale for the rise and fall of the current drawn from a voltage source (11). Power is converted by cyclically transferring a quantum of energy from the voltage source (11) to a current sink (load) via the effective LC circuit. The sink current is cyclically carried by a rectifier (16) which prevents the LC circuit from becoming a resonant circuit and leads to a unidirectional flow of energy from source to load.

Noise sources and calculation techniques for switched capacitor filters

Abstract: The noise response of switched capacitor networks (SCNs) is reviewed with emphasis on simplifying approximations suitable for SPICE noise simulation. The techniques developed cover all op-amp noise sources, as well as capacitor switching noise. The close agreement between predicted and measured noise responses for several monolithic SCNs bears out the validity of these simulation techniques.

Oil deterioration detector method and apparatus

Abstract: The degree of deterioration of lubricating oil used in an internal combustion engine is detected by measuring the lubricating oil dielectric constant with a pair of spaced sensor capacitor electrodes in the lubricating oil. The sensor capacitor is connected to a fixed capacitor to form a voltage divider connected across a constant frequency AC voltage source so that a developed voltage across the sensor capacitor corresponds to the lubricating oil dielectric constant. The frequency of the AC voltage is set at a value ranging from 50 KHz to 500 KHz.

Plasma ignition system for an internal combustion engine

Abstract: An N cylinder internal combustion engine plasma ignition system comprises a DC-DC converter for boosting low DC voltage to high DC voltage. Each of N ignition energy charging circuits includes a first capacitor connected between the DC-DC converter and ground via first and second diodes. The capacitor is charged by the DC-DC converter. Each of N reverse blocked thyristors connected to a junction of the first diode and first capacitor selectively grounds an electrode of the corresponding first capacitor to discharge ignition energy stored in the first capacitor. For each cylinder a transformer connected between the first capacitor and a spark plug boosts and feeds the discharged energy to the plug. One end of the transformer primary winding is grounded via a second capacitor to generate a damped oscillation when the corresponding thyristor grounds the first capacitor. An ignition trigger signal generator sequentially triggers the corresponding thyristor in a predetermined ignition order whenever the engine revolves through a predetermined angle and supplies a pulse to the DC-DC converter in synchronization with the ignition trigger signal. Derivation of the high DC voltage is halted for a period of time according to the pulsewidth. Each of N core-less inductors connected in series with the secondary winding of a transformer restricts an abrupt large current flow from the corresponding spark plug, to extend the discharge duration of each spark plug and ignite the air-fuel fixture stably without misfire.

Novel lossless synthetic floating inductor employing a grounded capacitor

Abstract: A new lossless synthetic floating inductance circuit, employing a grounded capacitor and CC IIs as active elements, is presented which, in contrast to recently reported circuits, does not require any component-matching condition for the desired realisation. The other novel features of the circuit are use of a minimum possible number of passive components and inductance control through a single grounded resistor.

Apparatus for reducing polarization potentials in a pacemaker

Abstract: A method and apparatus embodied in a pacemaker for attenuating polarization currents or voltages at the output terminals of the pulse generator. A heart pacemaker typically possesses a source of supply voltage, an output capacitor, an output terminal adapted to be coupled to heart tissue. A voltage source is coupled to the output capacitor during a first time interval for charging the output capacitor to a certain voltage. The output capacitor is coupled to the output terminals during a second time interval to discharge its voltage into the heart tissue. A resistor is coupled across the output terminals for providing a current path for the discharging and recharging of the effective capacitance of the stimulated heart tissue. The resistor may be coupled across the output terminals only during the first time interval and not during the discharge of the output capacitor.

Apparatus for and method of determining a capacitance

Abstract: An apparatus for determining a capacitance includes a capacitor, an oscillator, and a detector. The capacitor is partially immersed in liquid containing gasoline and alcohol in such a manner that the liquid may enter the capacitor, whereby the capacitance of the capacitor varies with the level of the liquid. The oscillator is connected to the capacitor and generates a oscillatory signal which depends on the capacitance of the capacitor and the frequency of which is set higher than a reference value dependent on the alcohol concentration in the liquid. The detector is connected to the oscillator and measures the capacitance of the capacitor according to the oscillatory signal of the oscillator to determine the level of the liquid.

Electronic delay blasting circuit

Abstract: An electronic delay blasting cap (10) receives an input signal over leg wires (12, 14). The input signal is passed through a rectifier (16) to produce a D.C. signal on output lines (26, 28). The D.C. signal charges a storage capacitor (32). When the input signal is removed or the wires (12, 14) are opened or shorted, the charge storage capacitor (32) discharges through a resistor (36) to produce a voltage which charges a timing capacitor (38). When the voltage on capacitor (38) reaches the threshold voltage of a zener diode (48) the diode is rendered conductive which in turn activates an SCR (46). A resistive ignition element (44) is connected in series with the SCR (46) and the charge storage capacitor (32) and is ignited when the SCR (46) is turned on. The charge stored in capacitor (32) causes ignition of the ignition element (44).

Micropower switched capacitor biquadratic cell

Abstract: The implementation of the double correlated sampling noise reduction technique in conventional strays-insensitive switched capacitor biquad building blocks is described. The function is performed by an offset cancellation circuit which is incorporated into the structure without the use of any additional capacitor, only minor modifications in the switching topology, and one supplementary clock phase. Consequently, a significant reduction of the low-frequency (1/f) noise is made possible and the usual differential amplifiers may be replaced by simple inverting amplifiers operated in class AB, featuring high-speed, low-quiescent power dissipation and low noise. An experimental micropower SC biquadratic filter section designed for `leapfrog' or `follow-the-leader feedback' structures has been developed using high gain (>80 dB) CMOS push/pull inverting amplifiers together with a three-phase clocking sequence. The integrated circuit, implemented in a low-voltage Si-gate CMOS process, achieves excellent accuracy and less than 5 /spl mu/W power dissipation with a 32 kHz sampling rate and /spl plusmn/1.5 V supplies; dynamic range is 66 dB.

Efficient and fast-switching telemetry transmitter

Abstract: A transmitter for a medical prosthesis which is highly efficient, and also permits rapid starting and stopping so that the same coil can be used for both transmission and reception without undue delays between the two modes of operation. During transmission, a tuned circuit, consisting of the coil and a capacitor, is pumped at a frequency equal to the resonant frequency. Transmission is concluded when almost all of the energy in the tuned circuit is in the form of a voltage across the capacitor and when the current through the inductor is approximately zero. This allows the inductor to be used immediately for reception. At the start of the next transmission cycle, the voltage which is maintained across the capacitor is used to initially energize the tuned circuit.

Multilayer, fully-trimmable, film-type capacitor and method of adjustment

Abstract: A thick film capacitor with more than two layers configured to enable trimming of the lower layers to increase the capacitance per area ratio while maintaining a linear trimmability of the capacitor's complete range.

Current source inverter commutation-spike-voltage protection circuit including over-current and over-voltage protection

Abstract: An adjustable-frequency three phase motor control system (2, CSI, M) is provided with a spike voltage clamp (SVC) to control the magnitude of voltage spikes generated during commutation of the current source inverter (CSI) thereby to protect the low voltage power devices (12a-c, 14a-c, SCRl-6) from damage. This spike voltage clamp comprises a rectifier bridge (32) connected to the output terminals (01, 02, 03) of the inverter (3) a storage capacitor (C) connected across the rectifier bridge output terminals, and a spike voltage dissipating resistor (Ra, Rb) and a gate turn-off thyristor (GTO) connected in series across the capacitor. A clamp control circuit (CC) precharges the storage capacitor and senses an increasing voltage thereon in response to voltage spikes across the motor terminals and gates the thyristor (GTO) to allow the resistor to dissipate a portion of the energy of the voltage spikes thereby limiting the magnitude of the voltage spikes. This clamp control circuit (CC) additionally includes an over-current sense circuit (OCS) that provides a fault trip signal if the resistor clamp is not turned off at the end of a required interval, and an over-voltage sense circuit (OVS) that responds to a higher spike voltage to provide a trip signal. This over-voltage trip signal and the over-current trip signal are fed to a common fault trip circuit (FT) which provides a gating signal to a fault thyristor (FSCR) thereby to provide an output signal which may be used to safely stop the motor control system. Whenever the spike voltage decreases below the voltage on the storage capacitor (C), the capacitor voltage blocks the three phase full-wave rectifier bridge (32) to decouple the resistor clamp circuit from the motor. When the voltage on the storage capacitor decreases to a required value, the clamp control circuit senses the decreasing voltage and gates thyristor GTO off to cause the resistor to be disconnected from the circuit.

Electronic microwave oven power supply

Abstract: A power supply for a magnetron is adapted to be powered from a regular power line and comprises an inverter means operable to provide an AC voltage of relatively high frequency. This relatively high-frequency AC voltage is applied to a step-up transformer, which transformer exhibits a relatively high leakage inductance between its input and output windings. A capacitor is connected across this transformer's output winding and effectively resonates with the internal inductance thereof. A rectifier and filter means is connected in parallel circuit with this capacitor, and provides an output of current-limited substantially constant-magnitude DC voltage for application to the magnetron. As a result, the magnetron is efficiently powered with a nearly constant DC voltage, as contrasted with the pulsed DC voltage normally used for powering magnetrons.

Integrated circuit formed on a semiconductor substrate with a variable capacitor circuit

Abstract: A MOS type semiconductor integrated circuit comprising a C-MOS inverter including P- and N-channel MOS transistors connected in series between VDD and VSS power supply terminals, the gates of the MOS transistors being supplied with an input signal; a variable capacitor connected between a node at which the transistors are interconnected and a reference voltage; and a voltage generator for producing an output voltage to the variable capacitor, the voltage generator being capable of irreversibly changing the level of the output voltage, thereby changing a capacitance of the variable capacitor.

Integrated circuit device having internal dampening for a plurality of power supplies

Abstract: The present invention is directed to an integrated circuit device comprising a lead frame having a ceramic capacitor mounted thereon and forming the support for a silicon chip bearing a multiplicity of circuits, including at least two power supply circuits namely a main power supply circuit and a secondary circuit. The capacitor is shunted across the terminals of the main power supply and the main power terminals of said IC chip. A conductive layer disposed atop the ceramic uppermost layer of the capacitor defines with the uppermost electrode of the capacitor, a second capacitive load of lesser value than the main capacitor, the said second capacitive load being shunted across the terminals of the secondary power supply and a secondary set of power terminals of said chip. The provision of internal capacitive shunting for the plurality of power supplies for the chip enables lead length to the capacitors to be maintained at a minimum thereby minimizing inductive reactance and thus enabling small capacitances to effectively dampen noise and pulses in the circuit.

Deflection systems and ramp generators therefor

Abstract: A ramp generator comprises an integrating capacitor and a current source connected to the capacitor to charge the capacitor and thereby generate a ramp signal. A switching device is connected to the capacitor and is operative to discharge the capacitor periodically in response to a periodic control signal applied to a control terminal of the switching device. A comparator has a first input terminal connected to a peak detector, which detects the peak value of the ramp signal, and a second input terminal connected to receive a reference voltage. The comparator compares the peak value of the ramp signal and the reference voltage and is connected to the current source to control the rate of supply of current to the capacitor in response to the comparison result so as to maintain a predetermined relationship between the amplitude of the ramp signal and the reference voltage, independently of the frequency of the control signal.

Non-dissipative LC snubber circuit

Abstract: Non-dissipative snubber for a DC power switching circuit comprising a main inductance connected in series with a load, a controlled switch, an inductance, and a DC voltage source The snubber includes a branch circuit including a capacitor, a first diode, and an auxiliary inductance in series, mounted in parallel across the switch, with one terminal of the capacitor directly connected to the junction of the switch and the main inductance The other terminal of the capacitor is connected through a second diode to a point of constant potential having a value about half that withstood by the switch The snubber permits the use of a capacitor of lower voltage rating than heretofore required

Offset-nulled sample-and-hold amplifier

Abstract: A high performance operational amplifier 12 circuit 10 nulls the offset voltage by means of switched capacitors (C 2 , C 3 ) and holds the signal output 18 during the nulling. Switching is in response to two non-overlapping pulse trains φ 1 , φ 2 . During an output valid phase φ 1 , with the signal input source connected to the inverting input 14 of the amplifier 12, an offset voltage storage capacitor C 2 is connected between the non-inverting input 16 and ground. A signal storage capacitor C 3 is connected between the output 18 and ground. During a nulling phase φ 2 , the signal storage capacitor C 3 is disconnected from ground and connected between the output 18 and the inverting input 14. The previously grounded side of the offset voltage storage capacitor C 2 is switched to the inverting input port 14. The non-inverting input port 16 is grounded. The offset storage capacitor C 2 charges to the input offset voltage, while the inverting input 14 is reset to virtual ground. When the circuit 10 is reconnected in the φ 1 valid output phase, the offset is compensated by the input offset storage capacitor C 2 without the output 18 having been directly connected to the inverting input 14. This makes possible a shorter settling time. Also disclosed as optional is an output offset limiting feedback network 35 for preventing a locking of the circuit 10 which can result from excessive initial offset voltage and a capacitor C 4 connected between the input side of the signal hold capacitor C 3 and the inverting input 14 to prevent sensitivity to clock leakage.

Resonant current-driven power source

Abstract: A resonant current-driven power source is disclosed. Preferably, the power source is a DC to DC converter regulator including an inductor and capacitor electrically coupled to one another and an input inverter which converts an input DC voltage into an AC voltage having substantially no DC component and applies the AC voltage across the inductor and capacitor in a manner which causes the inductor and capacitor to resonate with one another whereby an AC voltage appears across the capacitor. An output circuit converts the AC voltage appearing across the capacitor into a DC output voltage. A control circuit is provided for controlling the operation of the inverter circuit in a manner which controls the magnitude of the output voltage.

High intensity ultrasonic generator

Abstract: A high intensity ultrasonic sound generator for producing bursts of ultrasonic frequency and a method of controlling vermin and pests by projecting such bursts into a space from which such vermin and pests are desired to be eradicated. The apparatus has a transformerless power supply employing a voltage divider with a low leakage input capacitor and an output capacitor having a significantly larger capacitance than that of the input capacitor, and wherein the load is voltage dependent so that the greater the charge on the output capacitor, the greater the load and, therefore, the output capacitor is prevented from excessively charging. Ultrasound frequency is generated by two astable multivibrators one of which duty cycles the other and means are provided to vary the frequency within each burst and the burst interval. Means are provided, including parallel LC network with the transducer, which may be set to resonance, in order to reduce unwanted audio, and also including means for rounding the envelope of the bursts of ultrasonic frequency. The speaker includes a free floating cone, with no other mechanical connection than its mechanical connection to the transducer.

High-pressure metal vapor discharge lamp igniter circuit system

Abstract: To insure reliable starting, a superposition igniter circuit utilizes an iliary capacitor (10) which has a resistor (6) connected in parallel thereto. This parallel arrangement is serially connected with a pulse capacitor (7) and a choke (2) to form therewith a series oscillatory circuit which is connected directly with the primary winding (8, 13) of the pulse transformer (4, 11) in order to raise the lamp voltage during ignition. The parallel connection of the auxiliary capacitor (10) and the resistor (6) forms a load impedance for the pulse capacitor (7); the series circuit of the auxiliary capacitor (10) and the pulse capacitor (7) form a high-frequency short-circuit capacitor system. A voltage-sensitive semiconductor switch (9), such as a four-layer diode or a triac, disconnects the auxiliary capacitor (10) after lamp ignition, thus interrupting the series auxiliary circuit, permitting only normal supply voltage to be applied to the lamp (1).

MOS Driver circuit having capacitive voltage boosting

Abstract: An MOS driver circuit having a capacitive voltage booster is provided. A first capacitor which is charged to a supply voltage potential is used to control a precharge device which charges a second capacitor. The charge on the second capacitor is sequentially translated by a logic portion to provide a boosted driver voltage which is substantially greater than the supply voltage to an active driver circuit. The output driver circuit may be completely disabled to eliminate a standby current in the output.

Power supply for low voltage incandescent lamp

Abstract: A power supply providing power to a low voltage lamp utilizing a main capacitor connected electrically in series with the lamp, across an alternating current source, and an auxiliary capacitor connected electrically across the main capacitor by a switching device during selected portions of the source waveform cycle. The minimum lamp current is established by the main capacitor, with additional lamp current flowing through the auxiliary capacitor during portions of the source waveform cycle when the auxiliary capacitor is electrically connected across the main capacitor. The load current is adjusted over a desired range established by the magnitude of the main and auxiliary capacitors.

Microbox for electronic circuit and hybrid circuit having such a microbox

Abstract: The invention relates to microboxes for encapsulating electronic circuits. Electronic circuits frequently comprise decoupling capacitors or the like, which occupy a large amount of space compared with the integrated parts of the box. The invention provides for the use of the bottom or substrate of the encapsulating box as capacitors after metallizing the two faces. The dielectric material is matched to the desired capacitance values. The microbox substrate is formed by a multilayer capacitor for high values.

A derivation of the switched-capacitor adjoint network based on a modified Tellegen's theorem

Abstract: A method of generating an adjoint network for switchedcapacitor (SC) circuits with periodic switching and piecewise-constant inputs is derived in a general manner using a modified form of Tellegen's theorem. The derivation is independent of the method used to formulate the network equations. It is shown that under certain conditions the adjoint network may be described by the transposed system equations of the original switched capacitor circuit. The SC adjoint network is applied to the problem of determining the transfer functions from many input ports to a single output port.

Multiple spark CD ignition system

Abstract: Disclosed herein is a multiple spark circuit for use with a capacitor discharge ignition system including a current supply, a charge capacitor, an ignition coil primary winding, and an ignition timing SCR. The multiple spark circuit includes a charge reservoir capacitor connected to the current supply, a restrike circuit subject to the timing SCR, and to the voltage and discharge current of the charge capacitor, for allowing repeated charging and discharging of the charge capacitor to produce multiple ignition sparks at each ignition timing point, and a charge interrupt circuit, subject to the restrike circuit, for allowing repeated charging of charge capacitor by the charge reservoir capacitor at each ignition timing point. The restrike circuit preferably comprises a thyristor connected to the timing SCR and charge capacitor, and a zener diode connected to the thyristor gate and anode to render the thyristor conductive when the charge capacitor voltage exceeds a predetermined upper limit. The charge interrupt circuit preferably includes a Darlington transistor connected between the charge reservoir capacitor and the charge capacitor, with the base connected to the current supply and to the ignition coil primary winding, whereby, when the charge capacitor is discharging, the base current is shunted to interrupt charging of the charge capacitor by the charge reservoir capacitor.

Proximity switch with oppositely polarized coils

Abstract: A proximity switch comprising a detection coil, a first capacitor connected in parallel with the detection coil for forming a resonant circuit, an auxiliary coil, a second capacitor connected in parallel with the auxiliary coil for forming a resonant circuit, an oscillation circuit connected to the detection and auxiliary coils which are connected in series and in reverse winding directions, and an output circuit connected to the oscillation circuit for receiving variations in output generated from the oscillation circuit, the second capacitor having a capacitance larger than that of the first capacitor so that the second capacitor has a reduced low impedance at an oscillation frequency determined by the detection coil and the first capacitor.

Circuit for generating a substrate bias voltage

Abstract: An oscillator circuit which generates a periodic signal is connected to an input side of a capacitor and the output side of the capacitor is connected via a rectifier circuit to a semiconductor substrate and also to a reference voltage potential. The characteristic feature of the present invention is to provide a current limiting circuit which limits the peak value of the current which flows in the capacitor when the rectifier circuit is placed in the conductive state.

FET Gating circuit with fast turn-on capacitor

Abstract: A fast turn-on FET circuit is provided by a constant current source and fast turn-on capacitor combination in the gate circuit of the FET. At turn-on, a bypass capacitor momentarily short-circuits a control resistor in the current source such that a momentarily higher current is supplied by the current source to the FET gate until the capacitor is charged, whereafter constant current as controlled by the resistor is supplid to the FET gate circuitry to maintain conduction.

Advanced printed-circuit board design for high-performance computer applications

Abstract: A new integrated circuit packaging structure was needed to support the new 90-mm multilayer ceramic modules, known as Thermal Conduction Modules (TCMs), used in the IBM 3081 computers. The structure developed eliminates one level of packaging (the card level) and allows up to nine TCMs to be plugged directly into a large multilayer printed-circuit board using a new zero-insertion-force connector system. The board has 18 internal circuit planes for signal and power distribution and accommodates new signal cabling, power bus, terminating resistors, decoupling capacitors, and cooling hardware, forming a packaged unit of up to a quarter million logic gates and half a million bits of memory. This paper focuses on the detailed design of the printed-circuit board and on its signal and power transmission characteristics.