A current controlled switch to compensate for switching time variations. A compensated current source is configured to operate with a current mirror to set the switching current. The control of the switching current maintains control of the peak switching current in the switch, therein controlling the switching transition time. The speed performance is maintained nearly uniform as circuit and process variations cause switching conditions to change. Applications such as delay lines, output buffers, inverters and ringing oscillators are available using the current controlled switching technique of the present invention. Also, parasitic effects can also be compensated by using the present invention.

Current controlled solid state switch

A current difference current source which provides a stable current as operating conditions change. Two MOS transistors operate as two current sources. A difference current is obtained by subtracting the two transistor currents. The two current sources are configured to vary similarly as conditions change, such that their difference remains constant. In the alternative the difference current is forced to decrease as current increases in the transistors, wherein a reverse compensated current is provided. The difference current is used to drive a current mirror which functions as a compensated current source.

Current difference current source

In a semiconductor device such as a CSP, re-wiring is provided on a circuit element formation region of a semiconductor substrate and a columnar electrode for connection with a circuit board is provided on the re-wiring. A first insulating film is provided over the semiconductor substrate excluding a connection pad, and a ground potential layer connected to a ground potential is provided on an upper surface of the first insulating film on the circuit element formation region. A re-wiring is provided over the ground potential layer with a second insulating film interposed. Since the ground potential layer serves as a barrier layer for preventing crosstalk between the re-wiring and circuit element formation region, it is possible to eliminate crosstalk between the re-wiring and a circuit within the circuit element formation region and to freely position the re-wiring without restrictions. Furthermore, a thin-film circuit element may be provided at a given location on the second insulating film. In a structure wherein the thin-film circuit element is provided on the second insulating film, a second ground potential layer is provided as a second barrier layer over the thin-film circuit element with an insulating film interposed, and re-wiring is provided over the second ground potential layer with an insulating film interposed. Thereby, crosstalk between the re-wiring and thin-film circuit element can be eliminated, and the re-wiring can be freely positioned without restriction.

Semiconductor device having a barrier layer

A linear capacitance displacement transducer for measuring absolute displacement is formed from a coaxial variable capacitor and a precision capacitance measuring electronic circuit. The plates of the coaxial capacitor are attached to the members of an assembly whose displacement relative to one another is to be determined. Linear displacement of the members causes a linear displacement between the capacitor plates which is reflected in a linear capacitance change. A capacitor controlled oscillator utilizes the coaxial variable capacitor at its input. The capacitor controlled oscillator whose period of oscillation is been determined by the capacitance and locked in phase with changes of capacitance is utilized as a precision measure of capacitance. The period of the square wave output of the oscillator is a linear function of the capacitance of the variable capacitor at any time. The transducer may be adapted to determine the absolute position of a piston rod in a hydraulic cylinder.

Linear capacitance displacement transducer

By compensating for the base-emitter voltage of the transistor T1 by means of the base-emitter junction of the transistor T2 it is achieved that the voltage across the impedance Z1a is equal to the input voltage Vi. The current through the impedance Z1a and the equal output current Io are then proportional to the input voltage Vi and are highly linear.

Voltage-to-current converters

The invention relates to an integrated voltage-current converter circuit for generating a current which produces a voltage drop across a reference resistor, which voltage drop is determined by an input voltage. In order to compensate for the spread in width of the reference resistor formed in the integrated circuit, this reference resistor is formed by two parallel-connected resistors having the same resistance per unit area, the same length and different widths, and the compensated output current is formed by the difference between the currents which flows through these resistors.

Voltage-current converter having reference resistor spread compensation

Bei einem monolithisch integrierten RC-Oszillator mit nur einem externen frequenzbestimmenden Netzwerk aus Kapazitat (C o ) und Entladeschaltung (R o ) ist mit dem Netzwerk eine periodisch ein- und ausschaltbare Ladeschaltung verbunden, die von einer zwei Schaltschwellen (U 1 ,U 2 ) aufweisenden Schwellwertschaltung (2a,2b,3) ein- bzw. ausgeschaltet wird, wenn die Spannung an der Kapazitat (C o ) des Netzwerkes die untere (U 1 ) bzw. die obere (U 2 ) Ansprechschwelle erreicht. In a monolithic integrated RC-oscillator having one external frequency determining network of capacitance (C o) and discharge circuit (R o) is connected to the network periodically switched on and off charging circuit connected, by a two switching thresholds (U 1, U 2) having threshold circuit (2a, 2b, 3) is switched on or off when the voltage across the capacitance (C o) of the network the lower (U 1) and the upper (U 2) reaches threshold. Um sicherzustellen, das die Frequenz der erzeugten Sagezahnschwingungen nicht mehr von einem mit Streuungen behafteten, fest eingestellten Aufladestrom und dessen Temperaturkoeffizient abhangig ist, wird der Ladestrom (I o ) der Ladeschaltung von der Spannung (U,) uber einer zweiten Kapazitat (C,) gesteuert, die wahrend des Entladens der frequenzbestimmenden Kapazitat (C o ) mit einem Strom (I,) auf- bzw. entladen und wahrend des Aufladens der Kapazitat mit einem Strom (1 2 ) ent- bzw. aufgeladen wird. To ensure that the frequency of the sawtooth waves generated not affected by a with variations, fixed charging current and its temperature coefficient is dependent upon the charging current (I o) of the charging circuit of the voltage (U,) via a second capacitance (C) is controlled, that is during the unloading of the frequency-determining capacitor (C o) with a current (I,) up and unloaded and during the charging of the capacitor with a current (1 2) discharging or charging.

Monolithic integrated RC-oscillator

In an overtone crystal oscillator comprising a crystal oscillator having a feedback loop and a resonance amplifier whose amplitude characteristic has an overshoot in the range of the resonant frequency of the resonance amplifier and which is arranged in the feedback loop of the crystal oscillator, the resonant frequency of the resonance amplifier is between the frequency of the overtone to be generated and the next lower oscillation frequency of the crystal oscillator, while signals in the frequency range of the next lower oscillation frequency(ies) in relation to signals in the frequency range of the overtone to be generated in the feedback loop, particularly in the resonance amplifier, have such a phase shift that the overtone crystal oscillator cannot oscillate at the frequencies of the next lower oscillation frequency(ies) and that it only oscillates at the frequency of the overtone to be generated.

Cord Heinrich Kohsiek

Papers

Voltage-current converter having reference resistor spread compensation

Monolithic integrated RC-oscillator

Overtone crystal oscillator having resonance amplifier in feedback path

Integrierte schaltungsanordung mit einem spannungs-strom-wandler

Integrated circuit arrangement comprising a voltage current converter