Abstract: The device and method monitor the current delivered to a load through a power transistor including a sense transistor. The circuit includes a disturbances attenuating circuit that has a differential stage, and first, second and third stages referenced to ground, the respective input nodes of which are connected in common to an output node of the differential stage. The third stage is formed by a transistor identical to a transistor of the first stage and delivers a current signal through a current terminal thereof, proportional to the current being delivered to the load.

Abstract: A differential voltage magnitude comparator to receive a differential input signal and a differential reference signal, in which a magnitude difference of the differential input signal is compared to the magnitude difference of the differential reference signal. An output state depends on the magnitude difference of the differential input signal to the magnitude difference of the differential reference signal. If the magnitude difference of the differential input signal is below the magnitude difference of the differential reference signal, the output is in one state, but if the magnitude difference of the differential input signal is above the magnitude difference of the differential reference signal, the output is in the other state. The comparison and logical operation to provide the output states are generated in a single stage.

Abstract: A dual output capacitance interface circuit (100) based on switched capacitor circuits and charge subtraction technique provides both voltage output (104) and frequency output (106). The circuit is programmable independently with sensitivity and offset adjustment, and is insensitive to fixed stray capacitance. Temperature compensation methods are described.

Abstract: A programming method (250) for digitally programming the adjustment of an electronic trim capacitor (212, 314, 414). In an initial step (252), programming is initiated by setting an enable terminal (224). In subsequent steps (254, 256) a pulse signal (226) then applied to a program terminal (222) and the number of pulses (228) provided to the programming terminal (222) while the enable terminal (224) is set determines the total number of capacitance increments for which the electronic trim capacitor (212, 314, 414) is programmed. The electronic trim capacitor (212, 314, 414) may be incorporated into an integrated circuit (12, 312) or a module (412) and the electronic trim capacitor (212, 314, 414) may be programmed and used “in situ” in a more general circuit (1) such as an oscillator (301) or an amplifier (401).

Abstract: In an improved charge pump bias generating circuit for a charge pump for a semiconductor integrated circuit device, the pump has a bias generator which has an input for receiving a pump enable signal. The bias generator generates a ramped bias signal in response to the pump enable signal. A voltage controlled oscillator has an input to receive the ramped bias signal and generates an oscillating signal having a frequency which is dependent upon the voltage of the ramped bias signal. As a result, the sudden turn on of the pump enable signal would cause a gradual turn on of the voltage controlled oscillator gradually turning on the clock output signal from the voltage oscillator, thereby reducing power surge in the circuit.

Abstract: The invention relates to an integrated circuit comprising a substrate, a conductive layer (1), at least one inductive element (2) superposed on said conductive layer and formed by a metallic turn having an outer contour and an inner contour, which bound between them a surface referred to as the radiation surface, and means for insulating the conductive layer from the inductive element. The conductive layer has a surface substantially identical to the radiation surface.

Abstract: The device for measurement of current exchanged between a battery (1) and electrical circuits (19) of a portable telephone includes a current sensor (21), connecting the battery (1) to the circuits (19), connected to a first input (22) of first integrating circuits (22-27), integrating the current measurement and controlling a comparator (28, 29, 34) detecting the crossing of a high threshold (Vs+) through the integral of the current and applying to a second input (23) of the first integrating circuits (22-27) a calibrated feedback signal to recall below the high threshold (Vs+), second integrating circuits (12-17) to integrate the feedback signals, providing a measurement of the current exchanged. The invention applies well to mobile telephones.

Abstract: A &Dgr;-&Sgr; converter comprises a &Dgr;-&Sgr; modulator and a digital filter. The &Dgr;-&Sgr; modulator has a comparator having two resonant tunnel diodes connected to each other in series between two terminals and a field effect transistor connected in parallel to one of the resonant tunnel diodes, a conversion input transistor for converting an input voltage into electric current, a capacitor provided so that charge amount thereof is decreased by flow of electric current through the conversion input transistor and an electric potential proportional to the charge amount is used for the input electric potential to the comparator, and a feedback transistor, to which an output of the comparator is inputted, operating in such a way as to increase the charge amount of the capacitance element when the output of the comparator becomes a high level.

Abstract: An isolation system is provided for generating a control voltage in a low voltage control system that is representative of the input voltage in a high voltage power system of an excitation system, such as in a rotating electrical apparatus. The control voltage isolation system includes a voltage-controlled oscillator for converting the input voltage into a first frequency signal corresponding to the input voltage. Fiber optic conversion and receiving devices are employed in conjunction with a fiber optic cable to transmit the first frequency signal from the high voltage power system to the low voltage control system. Utilizing a fiber optic device provides voltage isolation between the power system and the control system. The use of a fiber optic device for voltage isolation also resists the damaging effects of relatively high transient currents and voltages from affecting sensitive semiconductor components and the like in the control system.

Abstract: A cross coupled output stage for a transmitter. It is desirable to have high impedance for a differential cascode output stage of an externally terminated transmitter in order to improve return loss. However, at high frequencies, parasitic capacitances cause shunts at the output nodes due to drain to bulk capacitances and negative feedback loops due to gate-to-drain capacitance. In order to counteract this, cross coupled capacitors are connected to the circuit to cause a positive feedback loop. This counteracts the reduction in impedance causing the impedance to remain high over all frequencies and to improve the return loss.

Abstract: A delay circuit in accordance with the present invention includes: a first I2L inverter and a second I2L inverter connected in cascade with each other; and a capacitor interposed between a ground and a connecting point of the first and second inverters, wherein: the delay circuit further includes a current adjusting circuit having at least one third I2L inverter with a plurality of output terminals at least one of which is connected to an input terminal of the third I2L inverter; and the current adjusting circuit is connected to adjust a charge current of the capacitor. The configuration provides a delay circuit of simple circuit structure that accounts for a small area in an integrated circuit and that is capable of introducing any given delay and also provides a ring oscillator incorporating the delay circuit.

Abstract: An inverter type delay circuit, voltage-controlled oscillation circuit, and voltage-controlled delay circuit capable of realizing simplification of circuit configuration, reduction of an effect of power source noise, and reduction of jitter, wherein a delay circuit, voltage-controlled oscillation circuit, and voltage-controlled delay circuit comprised of a plurality of delay stages controlled in drive current in accordance with a bias voltage or a control voltage and determined in delay time by the drive current, adding a change of a power source voltage to the above bias voltage or control voltage by a predetermined ratio and supplying a result of the addition to the above delay stages to suppress the power source voltage dependencies of the delay times of the delay stages, or connecting by a predetermined ratio a plurality of delay stages having different power source voltage dependencies, for example, power source voltage dependencies of opposite delay times, to suppress the power source voltage dependenci

Abstract: A multi-channel synchronous voltage-to-frequency converter (SVFC) realized in an integrated semiconductor circuit. The multi-channel SVFC having an operational amplifier adapted to receive an analog data signal to be converted and a reset signal, the operational amplifier integrating the sum of the analog signal and the reset signal and generating an output signal as a function of the integrated sum; a comparator coupled to receive the integrated sum and a reference level signal, the comparator outputting a logic level signal as a function of the received reference level signal; a digital logic circuit in response to an external clock signal, the digital logic circuit receiving the logic level signal and generating a reset control signal and a frequency output pulse as a function of the logic level signal; and a reset source switch receiving the reset control signal and outputting the reset signal.

Abstract: A frequency oscillator tuning process at the manufacturing stage is replaced with an adjustment of a resonant circuit in the frequency oscillator during an operation of the oscillator. The adjustment utilizes a crystal oscillator, a frequency oscillator such as a voltage-controlled oscillator (VCO), and a trimmer in a phase-locked loop configuration to determine a correction voltage required for an untrimmed VCO to operate at a nominally specified frequency by adjusting an input tuning voltage for a resonant circuit.

Abstract: A circuit that digitizes a quantity of light received from a strobe according to the present invention, includes: a photoelectric conversion device that receives light from the strobe and generates an output corresponding to an intensity of the received light; a storage device that stores the output generated by the photoelectric conversion device; a constant quantity discharge device that holds a storage quantity at the storage device close to a specific value by discharging a constant storage quantity from the storage device over a specific period which is in synchronization with a specific sampling frequency and is shorter than the sampling cycle when the storage quantity at the storage device exceeds a predetermined threshold value and by implementing feedback control on the storage quantity at the storage device; and a received light quantity output device that outputs one or more pulse signals when the storage quantity at the storage device exceeds the predetermined threshold value.

Abstract: A closed-loop voltage-to-frequency (V/F) converter includes a voltage-controlled-oscillator (VCO) placed in a feedback voltage-locked loop (VLL). This converter achieves both wide bandwidth (for good phase-noise suppression) and good spurious rejection. The closed-loop V/F converter may be further configured in a larger phase-locked loop (PLL) to achieve accurate channel selection that is independent of temperature and process variations.

Abstract: In a frequency-voltage conversion circuit, integrating means gives a predetermined slope for rising or falling of a rectangular pulse signal. First comparing means compares an output value of the integrating means with a threshold value, and produces a pulse signal line having a pulse width corresponding to frequency of the rectangular pulse signal. Storing means stores and retains the threshold value. Smoothing means smooths the pulse signal line, and produces a voltage value corresponding to the frequency of the rectangular pulse signal. Second comparing means compares the voltage value with a reference voltage, and charges and discharges electric charge for the storing means on the basis of the comparison result.

Abstract: The invention is related to a method and a device for use in an apparatus, preferably a portable radiotelephone, equipped with a number of keys. Upon activation of a key, the device detects which key has been activated. The device comprises a signal generating unit which generates an oscillating signal whose character, e.g. frequency, unambiguously corresponds to the activated key. A signal detecting unit determines from the character of the oscillating signal a digital value which unambiguously indicates which key has been activated. An advantage offered by the invention is that the device can be implemented by use of simpler and cheaper circuits than prior known devices of similar type.

Abstract: A frequency detection circuit detects the frequency of a horizontal sync signal, and generates a mode switching signal corresponding to the detected frequency. A voltage-controlled oscillator constituting a PLL circuit has a plurality of oscillation modes obtained by dividing a frequency equal to an integer multiple of the frequency of the horizontal sync signal into a plurality of frequency ranges, and oscillates signals in the respective frequency ranges in accordance with control voltages output from a filter. The oscillation modes of the voltage-controlled oscillator are switched in accordance with the mode switching signal output from the frequency detection circuit. In the voltage-controlled oscillator, since the frequency range in each oscillation mode is narrow, the oscillation gain can be suppressed low, and a deterioration in jitter characteristics can be prevented.

Abstract: The conductance may be adjusted of an electronic circuit including a first electronic component having a nominal conductance with a given inaccuracy. The circuit includes at least one additional field effect transistor connected in parallel with the component. The sources of all field effect transistors are connected to a common source, the drains of all field effect transistors are connected to a common drain, and a control unit controls the gate voltage of each field effect transistor individually. The gate voltage is controlled by connecting the gate voltage of each field effect transistor either to a common gate or to the common source. The component may be used to form switches or amplifiers or to control the conductance of circuits including other electronic components serially connected with the electronic circuit.

Abstract: A voltage to frequency converter using a charge pump to restore the output voltage of the input integrator. The charge pump implementation allows the voltage to frequency converter's input to sense voltage above and below ground with a single supply using a charge pump, which can provide either a positive charge or a negative charge as the restoring force to the integrator. Inclusion of an interleaved charge pump provides advantages of implementation simplicity and of high performance. The voltage to frequency converter concentrates all offset and leakage errors at the input of the integrator amplifier, which in the preferred embodiment is a chopper stabilized amplifier providing very low offset. The voltage to frequency converter is intended for realization in integrated circuit form, providing very high performance in an integrated circuit having very low power requirements.

Abstract: A programmable and precise voltage-to-current converter (a.k.a. current source) that tracks temperature variations is presented. The voltage-to-current converter is implemented by placing a voltage reference circuit between the bases of the two transistors, or alternatively between a diode and a transistor, in a voltage controlled current source circuit which can be adjusted to track temperature variations. In one embodiment, the voltage reference circuit is a programmable digital-to-analog (D/A) converter. In a second embodiment, the voltage reference circuit is a differential amplifier.

Abstract: A frequency control circuit for an oscillator and a method therefor are disclosed and which frequency control circuit includes a flash cell having a cell transistor, a switching unit for outputting a first voltage to the flash cell in the program mode in accordance with an enable signal and outputting a second voltage in the read mode, a write driver for outputting a program voltage to the flash cell in the program mode in accordance with the enable signal, a bias unit for supplying a current to the flash cell in the read mode in accordance with the enable signal and generating a frequency control voltage which is proportional to a threshold voltage of the flash cell, and an oscillator for varying the frequency in accordance with the thusly generated frequency control voltage.

Abstract: A system and method for altering the effective operating frequency of an electronic system (e.g., an IC) in response to changes in temperature or current provides controlled and deliberate performance degradation. Reducing the effective operating frequency at high temperatures allows an IC to maintain a relatively stable power consumption. A first embodiment of the invention includes a temperature transducer, an Analog-to-Digital (A/D) converter, a select generator, and a clock frequency divider. The temperature transducer measures the temperature, which is converted by the A/D converter to a digital value. The digital temperature value drives the select generator, which generates one or more select signals. The select signals control the clock frequency divider to produce a clock signal with an effective clock frequency that depends on the measured temperature. According to a second embodiment of the invention, a current transducer is used instead of a temperature transducer.

Abstract: A substrate voltage generation circuit for a semiconductor device which is capable of decreasing the amount of current consumed by a charge pump. The circuit includes a burn-in detection unit for differently varying logical states of output signals .phi. in a normal mode and a burn-in mode, respectively, a mode judgement unit for outputting first and second voltages in the normal mode and the burn-in mode in accordance with an output signal from the burn-in detection unit, an oscillation unit for outputting voltages OSCV having different oscillation frequencies in accordance with the first and second voltages, and a charge pump for pumping an output voltage OSCV from the oscillation unit and generating a substrate voltage.

Abstract: An N-bit analog to biphase-encoded analog-to digital converter, which comprises (1) a biphase amplitude modulator responsive to an analog signal and a microwave pump carrier frequency f.sub.c for deriving a biphase-encoded carrier signal having a phase value determined by the current polarity of the analog signal and a peak amplitude determined by the current magnitude of the analog signal, and (2) an ordinally-arranged group of comparators. The modulator and the comparators, in order, derive fixed-amplitude, biphase-encoded output signals, each having a phase value indicative of a separate one of the most significant bit (MSB) to the Nth MSB in response to a biphase-encoded, modulated-carrier signal and the pump carrier frequency f.sub.c applied as inputs to each of the ordinally-arranged comparators.

Abstract: A voltage controlled oscillator circuit having a negative resistance section for supplying electric power to the voltage controlled oscillator circuit and a parallel resonance circuit includes a first variable capacitance diode and a second variable capacitance diode which are connected in parallel. The first variable capacitance diode varies its capacitance according to a first control voltage and thereby varies oscillation frequency of the voltage controlled oscillator circuit. The second variable capacitance diode varies its capacitance according to a second control voltage which is independent of the first control voltage, and thereby varies the oscillation frequency of the voltage controlled oscillator circuit independently. Coupling condensers are provided between the negative resistance section and the first variable capacitance diode, and between the first variable capacitance diode and the second variable capacitance diode to cut off direct current.

Abstract: A control circuit for distributed electrical equipment includes a relaxation oscillator configured for voltage to frequency conversion whereby the output frequency is proportional to the input voltage signal. An opto-coupler provides voltage isolation to the circuit and a standard 8-bit counter translates the frequency signals to a low voltage count data.

Abstract: A low power current-to-frequency converter circuit provides an output frequency signal F.sub.OUT having a frequency that varies as a function of a low level analog input current signal. The analog input current signal is typically generated by an implantable sensor element, designed to sense a particular substance or parameter within body tissue or fluids to which the sensor is exposed, with the magnitude of the analog signal providing a measure of the sensed substance or parameter. Conversion of the low level analog current to the output frequency signal facilitates transmission of the data signal over a shared data bus and other digital processing of the data signal.

Abstract: An electrical network creates a differential voltage signal and comprises a plurality of first impedance elements of substantially equal values which are connected to form an impedance bridge. The impedance of at least one of the first impedance elements changes in response to at least one selected external condition to which the first impedance elements are exposed. The network also comprises a second impedance element which has two nodes. The second impedance element is connected at these nodes between a first pair of the first impedance elements. The differential voltages are measured between these nodes and between another node or nodes with magnitudes and signs being dependent upon the change in the impedance of the first impedance elements.

Abstract: An electrical network creates a differential voltage signal and comprises a plurality of first impedance elements of substantially equal values which are connected to form an impedance bridge. The impedance of at least one of the first impedance elements changes in response to at least one selected external condition to which the first impedance elements are exposed. The network also comprises a second impedance element which has two nodes. The second impedance element is connected at these nodes between a first pair of the first impedance elements. The differential voltages are measured between these nodes and between another node or nodes with magnitudes and signs being dependent upon the change in the impedance of the first impedance elements.

Abstract: A cascoded cmos differential delay element is described. The delay element provides a controlled delay useful in forming voltage controlled oscillators or other circuits. The delay element provides high gain enabling it to be useful in multistage delay element circuits. The circuit described includes cascoded complementary differential amplifiers and replicated bias clamps.

Abstract: An optical receiving circuit comprises a photodetector, a differential transimpedance amplifier, a peak detector, a resistor network circuit and a discriminator. The transimpedance amplifier receives a current pulse converted by the photo-detector and outputs a non-inverting voltage signal and an inverting voltage signal of the same level. A peak detector for detecting a peak value of the non-inverting voltage signal. A resistor network circuit make an additional operations between an output signal from the peak detector and the inverted voltage signal, and between the non-inverting voltage signal and the non-inverting voltage signal, thereby generating two complemental voltage signals, which have the same amplitude and cross each other at a middle point of the amplitude.

Abstract: A measurement amplifier has an integrator circuit (2) and a reference current source (33) which supplies a reference current to the input of the integrator when the voltage set at the output of the integrator (2) exceeds or falls below a reference voltage. In addition, a differentiator, for example, is provided which receives the output voltage of the integrator (2) and supplies an output signal which is proportional to the variation in time of the output voltage of the integrator. The output voltage of the differentiator is proportional to the input current to be measured by the measurement amplifier. The measurement amplifier allows very weak input currents to be rapidly and accurately detected.

Abstract: A voltage-to-frequency converter having an analog-to-digital converter, based on analog components, for converting samples of an analog signal into corresponding digital words and a digital-to-frequency converter, based on digital components, for converting the digital words into a train of pulses having a pulse repetition frequency related to the analog signal. With such an arrangement, the digital-to-frequency converter and the analog-to-digital converter are adapted to operate at different rates. Therefore, the analog-to-digital converter may be optimized at one operating rate while the digital-to-frequency converter is adapted to operate at a higher operating rate and over a wide range of operating rates. This arrangement thereby enables a slower, analog component based, analog-to-digital converter to be used fabricated with CMOS technology along with the higher, variable operating rate, digital component based, digital-to-frequency converter.

Abstract: An infrared remote-control receiver employs at its front end a gyrator-configured transistor operating as a current-to-voltage converter, but derives its data information from a negative-going gyrator output pulse in preference to the more conventionally used positive-going pulse. This negative-going pulse may be wider than the positive-going pulse and reduces the bandwidth demand on subsequent processing circuitry. This enables low-bandwidth, low-current hardware to be used which makes the receiver ideal for use in battery-operated systems. Also, the negative-going pulse is easier to detect, as it directly follows a disturbance known to be in the opposite direction. The result is an increased receiver sensitivity.

Abstract: A frequency control circuit of an FM modulator with a small number of external parts and a low number of IC pins, including a non-linear D/A converter, a current generator circuit and an emitter-coupled multivibrator. The non-linear D/A converter for giving an analog optimum resistance value depending on digital frequency control signals includes a plurality of resistors weighted by K.sup.n (1<K<2 and n is a sequential natural number). The current generator generates a current .DELTA.I depending on the output resistance value of the non-linear D/A converter. An oscillating frequency of the multivibrator is determined in proportional to I.sub.o /4CF.DELTA.I (I.sub.o represents a current value of an operational current source, C represents a capacitance of a capacitor, R represents a resistance value of a resistor and .DELTA.I represents a current flowing in the resistor). When the oscillating frequency is controlled depending on .DELTA.

Abstract: In a voltage-frequency converter having an integration circuit for integrating an input voltage signal in positive and negative directions, a first comparator is connected to switch integration direction of the integration circuit and a second comparator is connected to compare an integration output signal and a threshold signal. A delay circuit delays one of rising and falling edges of a second comparator output signal to be used as the threshold signal. The second comparator compares the delayed signal with a reference signal varying in accordance with a temperature and produces a second comparator output signal by which the integrating direction is switched. By the use of the delayed signal and the temperature dependent reference signal, a frequency change in the second comparator output signal caused by response time delays of the comparators is compensated for.

Abstract: A light adjusting circuit for a flash lamp of a camera includes a current converting circuit for converting the current output from a photodetector into a voltage modulated signal suitable for a counter circuit. The current converting circuit uses a capacitor to convert the current output by the photodiode into a voltage. The capacitor voltage is compared to a base or reference voltage. The output of the comparator is used to mask a clock signal output from a high frequency oscillator. When the clock signal is unmasked, the pulse output from the current converting circuit is counted by the counter circuit to turn the flash lamp on and off. The output from the comparator is also used to controllably discharge the capacitor when the capacitor voltage exceeds the reference voltage.

Abstract: An integrated circuit includes an analog-signal manipulating circuit (ASMC) such as a filter having a transfer function with a frequency response that is determined by at least one RC product. The integrated circuit also includes separately an RC oscillator. The frequency-response-determining RC products of an RC component pair in the filter and an oscillator frequency determining RC component pair in the RC oscillator are digitally programmable by an external microprocessor. The microprocessor holds the frequency of the RC oscillator fixed relative to its own crystal controlled oscillator by adjusting the programmable RC component pair of the RC oscillator. The same adjusting digital signal from the microprocessor is simultaneously applied to the programmable RC component pair(s) of the ASMC, which has the effect of stabilizing all RC component pairs and thus the ASMC frequency response. The capacitors of each RC component pair have binary-control-signal lines mutually parallel connected to each other.

Abstract: Improved controller circuitry for a switching power supply is disclosed. The switching power supply is of the type having a transformer having primary and secondary windings for generating an output voltage at the secondary winding, a power switch for driving the primary winding, and controller circuitry for activating the power switch. The improved controller circuitry includes an oscillator and frequency shift means. The oscillator generates PWM pulses having a predetermined frequency for use in activating the power switch. The frequency shift means gradually shifts the frequency of the PWM pulses at a shift rate in response to the output voltage decreasing to below a threshold level. In another embodiment, a controller for use in a switching power supply includes an oscillator for generating PWM pulses having a predetermined frequency which determine the switching condition of the supply.

Abstract: A voltage to frequency converter including a first selector for receiving an input voltage and for generating an input current based on the control signal. The input current is proportional to the input voltage or an inverse polarity input voltage when the control signal designates plus, or minus integration period, respectively. The converter further includes a second selector for generating a reference current such that the reference current is on/off controlled based on the selection signal and a polarity of the reference current is determined by the control signal, and an integrator for integrating a resultant current of the input current and the reference current to obtain an integrated voltage. The integrator integrates the resultant current complementarily in a forward or in a reverse direction.

Abstract: A fully differential voltage controlled oscillator having a large common mode rejection ratio is disclosed with a first and a second phase detector disposed between the output of a differential comparator and the input of a differential triangle wave generator to insure 180 degree out of phase operation.

Abstract: A bipolar analog voltage is converted into a digital signal by sensing the polarity of the voltage and selectively supplying a bias voltage to an analog-to-digital converter, which can preferably be a charge balanced voltage to frequency converter, as a function of the sensed polarity. The voltage to frequency converter has a double valued variable frequency output with a discontinuity at zero volt such that the converter derives a maximum output frequency for a maximum positive voltage and also for a negative value slightly displaced from zero; the voltage to the frequency converter minimum output frequency is derived from positive voltages slightly greater than zero and for maximum negative voltages. The converter output frequency and the sensed polarity are supplied to a frequency to digital converter which derives an output signal having a bit representing the polarity of the analog voltage and additional bits indicative of the magnitude of the analog voltage.