Abstract: An oscillating circuit body 10 includes a first two-input NAND gate, a feedback resistor, a resonator and capacitors. One input terminal of the NAND gate functions as a control terminal to which is applied a first control signal to perform on-off control of oscillation operation of the circuit body. An output terminal of the circuit body is connected to an input terminal of a second two-input NAND gate via two inverters. The other input terminal of the second NAND gate is connected to a control terminal to which a second control signal is applied. The second NAND gate is used for masking the oscillatory output in response to the second control signal for a predetermined period, and the output from the second NAND gate is provided as a final clock output.

Abstract: A one-pin integrated crystal oscillator in a Colpitts configuration employs a differential amplifier, provided with a feedback network, as an input gain stage. This achieves an enhanced stability and independence from temperature variation, a high Q figure, and a short start-up with a relatively small area of integration.

Abstract: A quadrature oscillator is provided constructed of NOR gates in the manner of a non-linear circuit which is inherently unstable and which cycles sequentially through four distinct states at a rate determined by the constitution of the NOR gates. The quadrature oscillator includes first and second stages that each include first and second NOR gates. The output of the first NOR gate of the first stage is connected as an input to the second NOR gate of each of the first and second stages. The output of the second NOR gate of the first stage is connected as an input to the first NOR gate of each of the first and second stages. The output of the first NOR gate of the second stage is connected as an input to the first NOR gate of the first stage and the second NOR gate of the second stage. The output of the second NOR gate of the second stage is connected as and input to the second NOR gate of the first stage and the first NOR gate of the second stage.

Abstract: In a semiconductor memory device, a constant voltage is applied to a resistor having a positive temperature coefficient, whereby a first reference current flowing through that resistor is converted into a voltage by a resistor. That voltage is converted into a second reference current by a P channel MOS transistor, whereby a second current of a value equal to the value of the second reference current flows through each of a plurality of inverters by a current mirror circuit. These inverters are connected in a ring manner to form a ring oscillator. The first reference current becomes lower as the operating temperature rises, whereby the second reference current increases. As a result, the oscillator cycle of the ring oscillator becomes shorter as the operating temperature rises.

Abstract: An oscillator for generating a varying amplitude feed forward power factor correction (PFC) modulation ramp signal includes a clock generating circuit and a ramp generating circuit. The PFC ramp signal generated by the ramp generating circuit is used within a power factor correction circuit of a switching mode power converter. The timing capacitor used within the ramp generating circuit is charged from the full wave rectified line input voltage so that the amplitude of the generated ramp output signal will follow the full wave rectified input signal, thereby maintaining the current loop bandwidth at a constant value and improving the transient response of the circuit. A one-shot circuit is coupled between the discharge transistor of the clock generating circuit and the discharge transistor of the ramp generating circuit for synchronizing the clock and ramp reference signals generated by the oscillator so that the frequency of the ramp reference signal is equal to the frequency of the clock signal.

Abstract: A voltage controlled oscillator circuit with a high power supply rejection ratio incorporates a clamping transistor with respect to each output terminal which limits the signal swing of the output terminal. The limited voltage swing allows relatively large movements in the power supply and ground voltages without causing significant changes in the frequency of the output signals. Such an oscillator circuit may be incorporated into an integrated circuit characterized by noisy power supply and ground conductors. Additionally, multiple delayed versions of the output frequency may be created using a level shifter circuit and a buffer circuit. The oscillator circuit is relatively quick to react to changes in the controlling voltage, adjusting the oscillation frequency in a relatively short time interval.

Abstract: A monolithic microwave oscillator using a negative resistance cell includes a resonator, a negative resistance cell that employs an active device, an output buffer for voltage and current amplification, and a field effect transistor. The negative resistance cell includes a bipolar junction transistor as its active device, with the output buffer circuit coupled to a base of the BJT through the field effect transistor. The combination of the resonator and the negative resistance cell produce a periodic RF microwave signal that is sampled, amplified and buffered by the buffer circuit without degradation.

Abstract: The present invention teaches an oscillator and transmitter. The balanced oscillator comprises a resonator for generating a reference signal having a resonating frequency, a first oscillator for providing a first oscillating output in response to the resonating frequency, and a second oscillator for providing a second oscillating output in response to the resonating frequency. The second oscillating output has a magnitude equal to the first oscillating output while oscillating 180 degrees out of phase with the first oscillating output. The transmitter comprises an antenna for radiating the first and second oscillating output signals.

Abstract: Five CMOS inverters are connected in a series ring to form an oscillator. Current to the inverters is controlled to establish gate delays of the inverters and thereby determine a frequency of oscillation of the oscillator. The oscillator is included in a phase locked loop where the gate delay of the inverters is selected by selecting the value of a frequency divider of the phase locked loop. The selected delay is used to form a train of pulses with a desired duty cycle.

Abstract: A charge pump oscillator for regulating an oscillator frequency over a wide range of supply voltages is disclosed. Such a charge pump oscillator provides a charge pump system that provides a consistent current output over a range of supply voltages. The charge pump oscillator includes a reference circuit, a timing circuit, a latch circuit and a driver circuit.

Abstract: A ring oscillator circuit which provides an output signal having a substantially constant, fifty (50%) percent duty cycle. The circuit includes a plurality of cascaded inverting stages, each of which has an input circuit for detecting an output voltage of a preceding inverting stage. One inverting stage provides a voltage to an output node. A clamping circuit, coupled to the output node, provides current to the output node whenever the instantaneous voltage output at the output node departs from a threshold voltage of a subsequent logic circuit. The current is such as to clamp the average voltage output to the threshold voltage. The plurality of cascaded inverting stages is coupled to power supply voltage across capacitor configured transistors. The ring oscillator circuit can be employed within a voltage controlled oscillator.

Abstract: An oscillator circuit (150) is designed with a reference circuit (102), responsive to a first voltage, for producing a second voltage. An oscillator (108), responsive to the second voltage, produces a first output signal having a magnitude less than a magnitude of the first voltage. A level translator (114), responsive to the first output signal, produces a second output signal having a magnitude greater than the magnitude of the first output signal. Since the oscillator produces the first output signal with a magnitude less than the magnitude of the first voltage, power consumption is reduced with respect to an oscillator operating at the first voltage. The magnitude of the first output signal is increased by the level translator to a desired magnitude of the second output signal.

Abstract: A proximity switch circuit including first and second transistors Q4, Q6 connected as a long tail pair with an inductive sensing circuit LC connected to one leg thereof and an emitter follower circuit Q7, Q8 connected between said one leg and the base of the transistor of the other leg, whereby an oscillator circuit can be provided which is non-critically damped to enable faster speed of operation of the proximity switch.

Abstract: A low phase noise oscillator 10 having a balanced feedback transformer 24 and a push-pull resonant circuit 12 for generating an oscillation excitation signal. The resonant circuit 12 is loaded by an output buffer 20 connected between first and second feedback terminals 16 and 18. The feedback transformer 24 provides first and second feedback paths of opposite phase polarity which link the resonant circuit 12 with the first and second feedback terminals 16 and 18.

Abstract: An oscillator circuit having a 50% duty cycle comprises an oscillating stage and an output stage. The output stage comprises a series arrangement of first and second output transistors of complementary conductivity types. The oscillating stage applies a combination of an oscillating signal and a first DC bias to the gate of the first output transistor. The first DC bias is dependent on the amplitude of the oscillating signal. The oscillator circuit also includes a bias-generating circuit for generating a second DC bias at the gate of the second transistor, so as to adjust the input switching level to the median level of the input signal dependent upon the amplitude of the oscillating signal.

Abstract: A high performance oscillator with low frequency pulling at turn on includes an oscillator transistor, a resonating element and a common base buffer transistor. The resonating element of the oscillator is a circuit having a crystal resonator that is connected in parallel with a transformer winding. This resonating element is connected between the emitter of the oscillator transistor and the emitter of the buffer transistor. More specifically, a tap connects the emitter of the buffer transistor to the transformer winding of the resonating element. With this connection, a low transformed power oscillating output is taken from the collector of the buffer transistor with minimized degradation in the symbol of merit for the crystal oscillator.

Abstract: A ceramic resonator, a variable reactance circuit, and a limiter circuit are connected to the output of an amplifier having an output that is fed back to the positive phase-sequence input, and the frequency of oscillation is controlled by varying an equivalent capacitance of the reactance circuit with a control voltage applied to the reactance circuit. The limiter circuit ensures a variable frequency range on the high frequency side, and the symmetry of the capture range when this system is applied to a PLL can be improved.

Abstract: A highly stable, high frequency voltage controlled oscillator (VCO) for phase locked loops is adapted to be fully integrated on a single silicon chip and is operable over a wide frequency range without using off-chip capacitors. The VCO is a fully differential ring oscillator with fully differential voltage control. The VCO is constructed from basic blocks made of differential emitter coupled transistor pairs. Voltage control is provided by differential d.c. amplifiers which vary the capacitive load seen by the logic blocks.

Abstract: A low-power crystal-controlled CMOS oscillator wherein a long and wide additional transistor is provided in the first stage of the output amplifier. This prevents the output amplifier from diverting too much current from the primary amplifier stage during startup.

Abstract: A microwave voltage controlled oscillator (12) and isolation amplifiers (14, 16) are formed as a monolithic circuit on a single GaAs substrate. Only a single external inductor (34) is required to set the oscillation frequency. Optionally, an external resonator (38) may be used instead of an inductor. Off-chip active bias control (LIMin, 18) is provided for convenient frequency tuning.

Abstract: A low-power crystal-controlled CMOS oscillator wherein a long and wide additional transistor is provided in the first stage of the output amplifier. This prevents the output amplifier from diverting too much current from the primary amplifier stage during start-up.

Abstract: A transmitter including a continuous phase FSK modulator is disclosed for use primarily in optical transmission. The output frequencies are achieved by switching a capacitor into and out of an oscillator circuit by means of a PIN diode switch network which is responsive to a binary data input. The resulting sinusoidal waveforms are squared up by means of an inverte with feedback control for adjusting the duty cycle.

Abstract: A crystal oscillator uses automatic gain control to minimize the operating current through its inverting amplifier. The power supply potential to switching transistors of the amplifier is reduced by the automatic gain control to a level substantially equal to the sum of the switching thresholds thereof which minimizes simultaneous conduction through the switching transistors and associated operating current. The low level output signal of the amplifier becomes sinusoidal about a DC bias point operating at the resonant frequency of the crystal which eliminates undesirable harmonicas interfering with the crystal's natural vibration. The sinusoidal output signal may be buffered and level-shifted to a useable state.

Abstract: A crystal oscillator circuit wherein first and second transistors are connected to form a differential pair. The second transistor functions as an inverting gain stage for the oscillator and two capacitors are provided to complete a feedback path in series with a crystal which essentially functions as an inductor. The capacitors are large enough to minimize the effect of device parasitics and small enough for monolithic implementation. The square-wave output from the circuit is completely isolated from the oscillator gain stage, thus subsequent logic gates will not have any effect on the oscillator performance and DC-coupling can be used without a need for AC-coupling capacitors. The circuit is completely monolithic, requiring only an external crystal. The circuit inherently suppresses the fundamental frequency without a need for a tank circuit or a feedback resistor and does not influence the biasing.

Abstract: A circuit for producing four indications on a bicolor light emitting diode (LED) includes a ring oscillator, with two inputs controlling inverters of opposite phase. By enabling or disabling these inverters, either, both, or neither dies of the LED are energized, causing it to emit light of either of its two primary colors, a secondary color formed by the combination of its two primaries, or no light, respectively. Nonlinear resistances are used to equalize the brightness of the two primaries and set the hue of the secondary.

Abstract: A circuit comprising an oscillator having a load coupled thereto by means of at least one voltage-dependent coupling element that exhibits a high impedance at relatively low voltages and low impedance at relatively higher voltages. The voltage-dependent coupling element can comprise two series connected Zener diodes connected such that the anodes of the diodes are coupled together. The voltage-dependent coupling element can also comprise a varistor.

Abstract: A Colpitts oscillator has an integrated circuit. The integrated circuit includes a transistor having an equivalent large size, a bypass capacitor connected between a collector of the transistor and a ground, a first feedback capacitor connected between a base and an emitter of the transistor, a second feedback capacitor connected between the emitter of the transistor and the ground, and an emitter follower connected to the emitter of the transistor. In a package, a stray reactance and a bonding wire are designed so as to agree with an element value and a Q value which can be used as parts of a resonator. A surface elastic wave resonator disposed outside the integrated circuit is connected between the base of the transistor and the ground. The oscillator is voltage controlled by a variable capacitance diode connected in series with the resonator.

Abstract: A phase-controllable oscillator consists of a capacitance and an apparatus for charging and an apparatus for discharging the capacitance. In addition, feedback is provided for activating the charging and discharging apparatus in dependence on the oscillator signal. An amplifier for amplifying the capacitance voltage can be phase-controlled by providing the amplifier with a control input for adjusting the phase difference between a zero-crossing of an amplifier output signal on the one hand and a reference phase in the oscillator signal on the other hand. In order to maintain the duty cycle, a switching apparatus is provided for reversing the polarity of the control input under the control of the oscillator signal.

Abstract: An oscillator is provided with an internal, high gain hysteresis effect so as to offset the linear regions of the waveform and to avoid spikes upsetting the count of a reference divider controlling the oscillator. The crystal (10) and capacitor (11) are connected between the base of one (T.sub.1) and the collector of the other (T.sub.2) transistor of a long-tailed pair, signals appearing at the collector thereof being fed via emitter followers (T.sub.5, T.sub.6) to a further long-tailed pair (T.sub.7, T.sub.8) having tapped collector resistors (R.sub.1, R.sub.2). The signal appearing at the tapping point of one of the further pair (T.sub.7) is fed to the base of a transistor (T.sub.3) whose collector-emitter resistor lies in the load circuit of one of the transistors (T.sub.1) of the first long-tailed pair.

Abstract: A low-power crystal-controlled CMOS oscillator wherein a long and wide additional transistor is provided in the first stage of the output amplifier. This prevents the output amplifier from diverting too much current from the primary amplifier stage during start-up.

Abstract: A low-power crystal-controlled CMOS oscillator wherein a long and wide additional transistor is provided in the first stage of the output amplifier. This prevents the output amplifier from diverting too much current from the primary amplifier stage during start-up.

Abstract: An oscillator has an oscillating circuit including a NOT circuit having first and second inputs and one output and is placed into an operable condition in response to a trigger signal applied to the first input of the NOT circuit. A frequency determining circuit is connected between the second input and the output of the NOT circuit so that the output of the NOT circuit generates an oscillation signal of a frequency which is determined by the frequency determining circuit. A comparator has a threshold level which is different from that of the NOT circuit and is connected to the output of the NOT circuit so as to generate a control signal when the oscillation signal exceeds the threshold of the comparator. Further, an output circuit is connected to the outputs of the oscillating circuit and the comparator for receiving the trigger signal for outputting the oscillating signal after the trigger signal is received and the control signal is generated.

Abstract: An oscillator with noise rejection which may be used in a gate array in a semiconductor chip including a first amplifier circuit, a circuit, for connecting an external feedback element (crystal) across the input and inverting output of the first amplifier circuit for generating and amplifying a sine wave, and a circuit connected to the inverting output of the first amplifier circuit for generating a square wave with the duty cycle thereof being proportional to the difference between the center of the voltage swing of the amplified sine wave and a reference voltage. In a preferred embodiment, the first amplifier circuit and the generating circuit each include a current switch. A voltage reference network is provided to set the reference voltage for the current switch in the generating circuit to the center of the voltage swing of the sine wave applied to that current switch. This results in a 50% duty cycle square wave for the output signal.

Abstract: Phase locked, pulsed oscillator apparatus, for example, for radar use, comprises a pulsed r.f. oscillator, a pulse repetition frequency (PRF) generator and a pulse shaping network. The PRF generator pulsed output signal of frequency, f.sub.1, is reshaped by the pulse shaping network to provide to the input gate of the r.f. oscillator a train of triggering pulses each having a very fast rise time, t.sub.r, which caues the triggering pulses to exhibit significant harmonic power near the r.f. oscillator's free running frequency, f.sub.FR. The reshaped pulses provided by the pulse shaping network gate the r.f. oscillator on and off and cause coherency of the pulsed oscillator output signal relative to the PRF generator output signal. The reshaped pulse rise time, t.sub.r, is preferably less than about 3-4, and more preferably is about two, times the oscillator output signal period, l/f.sub.FR. The peak turn on voltage, V.sub.p, of the reshaped pulses is preferably about twice the average voltage, V.sub.

Abstract: In a discharge lamp lighting system comprising a DC or low frequency (LF) AC main source and a high frequency (HF) source, a high frequency component from the HF source and low frequency component from the main source are supplied in an overlapping manner to the discharge lamp. The HF source of the lighting device is energized by input current from the main source for producing a high frequency current. In addition, the lighting device for the discharge lamp include in combination an HF blocking circuit, an HF passing circuit and/or a matching circuit for the HF source to supply effectively a high frequency component to the discharge lamp, as well as a low frequency component from the main source.

Abstract: An oscillator circuit having a variable duty cycle for controlling the power level of a microwave oven provides an adjustable RC time constant circuit including a capacitance branch and a resistance branch and coupling means therebetween, the resistance branch including a pair of alternately selectable current paths for the charging and discharging of the capacitance branch, the coupling means including semiconductor switch means for selecting and coupling either of the current paths to the capacitance branch for changing the charging and discharging of the capacitance branch in accordance with the selected current path, and one of the current paths including a pair of parallel connected portions with each of the parallel portions having a diode connected therein for controlling the direction of current flow, the diodes being connected with opposite respective polarities for allowing current flow only in opposite directions in the respective portions, the one current path further including a potentiometer hav

Abstract: An oscillating circuit provides first and second reference signals having a phase difference of 90.degree. with respect to each other. The oscillating circuit includes an oscillator providing the first reference signal at an output thereof, a voltage-to-current converting circuit, which may incorporate a common-base transistor, and a capacitor connected between the output of the oscillator and an input of the converting circuit. The output of the converting circuit then provides the second reference signal which differs in phase by 90.degree. from the first reference signal. The oscillator may include differentially connected transistors and an LC resonant circuit.

Abstract: An improved integrated circuit oscillator adapted for crystal-controlled applications eliminates the need for capacitors and duty cycle control circuitry by using a cascaded pair of push-pull complementary transistor amplifier stages, a clipping-type automatic amplitude control circuit, and a resonant feed back path between the two amplifier stages. In an illustrative embodiment, floating bias voltages are established by a chain of diodes, with several bias currents set with respect to the chain current by emitter area relationships. Square-wave output is provided by a flip-flop connected to push-up and pull-down output circuits.

Abstract: A circuit for controlling the rectifier circuit in an electrostatic dust precipitator, the circuit being an oscillator circuit utilising a pair of alternately conducting transistors and a timing circuit controlling conduction of one of the transistors, the other transistor controlling the circuit output.