Abstract: A ring oscillator for a semiconductor device comprising a ring oscillation circuit for generating a pulse signal according to a logic state of a control signal, the pulse signal having a predetermined period and a reduced operating voltage level, a comparator for comparing the pulse signal from the ring oscillation circuit with a reference voltage signal according to the logic state of the control signal and amplifying it in accordance with the compared result, and a driver for buffering an output signal from the comparator. The ring oscillation circuit includes an inverter chain for supplying the pulse signal with the reduced operating voltage level. According to the present invention, power consumption can significantly be reduced in the ring oscillation circuit.

Abstract: A harmonic of a resonance frequency of an oscillator, which occurs at the initial stage of the oscillation of the oscillator, is divided to obtain a pulse to be used as a clock for the operation of a microcomputer before the oscillation is stabilized. Thus, the invention provides a clock generation circuit and a microcomputer which shorten a time period required from the application of power or the clock halt state to the start of the operation of the microcomputer.

Abstract: This invention provides a synchronous, power down oscillating device that provides only uniform pulses having no glitches at its output. The circuit is able to provide a synchronous output for two low power stand-by modes of a battery powered device. The circuit includes an oscillator that sends an oscillator signal to a synchronizing chain of D flip-flops. Input to the flip-flops is provided through an OR gate. The output of the flip-flops is logically ORed with the oscillator signal. The resultant output from the circuit is always a synchronized signal.

Abstract: An electrical circuit for reliably starting the oscillation of an oscillator comprising a cylindrical piezoelectric body on which an exciting electrode, a feedback electrode which causes an oscillation, and an electrode for detecting an angular rate are mounted. The electrical circuit includes an exclusive OR gate for detecting a phase difference between an exciting voltage and a voltage developed at the feedback electrode, a circuit for integrating an output voltage from the gate and a band pass filter having its resonant frequency shifted in proportion to a voltage from the integrating circuit. The band pass filter is effective to provide an automatic adjustment of a phase difference of a voltage, which is actually fed back to the exciting electrode, with respect to a voltage developed at the feedback electrode.

Abstract: An oscillation circuit employs a piezo-electric crystal connected in parallel with an amplifier having a gain equal to or less than that needed to maintain a steady-state operation of the amplifier when operated at the maximum output. One or more controllable amplifiers are connected in parallel with the amplifier and controlled according to the level of the oscillation signal, to rapidly amplify an initial oscillation to steady-state operation level and to keep it there without exceeding the output level of the crystal while minimizing the energy supplied to the entire oscillation circuit.

Abstract: An oscillator circuit (30, 40) for starting-up and operating at low voltages has been provided. The oscillator circuit includes an inverter circuit(31, 41) coupled across first and second terminals of a resonant circuit (14). The inverter circuit includes a push-pull driver stage having a P-channel transistor (18) and an N-channel transistor (20). The common drain electrodes of each are coupled to the second terminal of the resonant circuit. The source electrodes of the P- and N-channel transistors are respectively coupled to first and second supply voltage terminals. The gate electrode of the first transistor is coupled to the first terminal of resonant circuit. The inverter circuit further includes a circuit (32, 42) for shifting the voltage level applied to the gate electrode of the second transistor, relative to the voltage applied to the gate electrode of the first transistor, by a predetermined voltage.

Abstract: A digital control system such as a digital temperature compensated crystal oscillator (DTCXO) system is arranged to offer superior oscillating performance with reduced size and cost. For example, to reduce the memory capacity, a memory 31 receives upper 6 bits of temperature data, and a decoder 32 calculates temperature compensation data from lower 4 bits and output data from the memory (FIGS. 1-11). For a one-chip configuration and low power consumption, a MOS type Colpitts oscillator (FIG. 16) is provided with a circuit for adjusting the source resistance of the MOS. For size reduction and fine frequency adjustment, a DTCXO is provided with sections such as an adder 341, an up-down counter 342 and an auxiliary frequency control section (AFC) 332 (FIGS. 20, 21, 24 and 25). An adding section 415 is provided between a D/A converting section 414 and a capacitance varying section 416 to obtain superior linearity with respect to a control voltage and quality of offset.

Abstract: The clock generator of this invention includes: an input shutoff control circuit for receiving a base clock and a reference clock and outputting a first signal and a second signal in response to a reset signal, a phase comparator for outputting a phase difference signal indicating a phase difference between the first signal and the second signal; a voltage control oscillator for outputting a frequency variable clock in correspondence with the phase difference signal; and a voltage fixing control circuit for controlling a voltage of the phase difference signal in response to the reset signal, wherein, when the reset signal is in a first level, the input shutoff control circuit: outputs the base clock to the phase comparator as the first signal and outputs the reference clock to the phase comparator as the second signal, and the voltage fixing control circuit holds the voltage of the phase difference signal, and when the reset signal is in a second level different from the first level, the input shutoff control

Abstract: A current source including a current mirror circuit and an active load circuit which form a reference branch, for setting a reference current value, and a mirroring branch, defining an output current value, connected between supply and ground. A voltage stabilizing transistor is interposed between the current mirror circuit and the load circuit in the reference branch only, and is so biased as to maintain its gate terminal at a predetermined voltage. As such, the potential with respect to ground of the drain terminal of the reference branch load transistor is fixed, so that its drain-source voltage drop (and the current through it) is substantially independent of supply voltage. The current source may be used to advantage in an oscillator for generating the: clock signal of a nonvolatile memory.

Abstract: Oscillation is easily and reliably initiated in an oscillator by increasing the gain of the circuit at startup time. For example, the gain of an oscillator circuit may be increased at startup by reducing the value of a user controlled impedance until oscillation commences. Alternatively, or in combination, the input impedance of an amplifier used in the oscillator may be reduced at startup to facilitate the initiation of oscillation.

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: An oscillation circuit in which the driving performance of a CMOS transistor therein for enabling/disabling an oscillating function is enhanced without unstabilizing the oscillation operation, by applying a higher potential to the back gate of the CMOS transistor when a signal other than an oscillation signal is inputted/outputted, and a lower potential when generating the oscillation signal.

Abstract: A ring oscillator for circulating pulse edges of two types therein includes an even number of inverting circuits connected in a ring. Each of the inverting circuits is operative to invert an input signal and output an inversion of the input signal. One of the inverting circuits is a first start inverting circuit which starts an operation of inverting an input signal in response to a first control signal applied from an external input. One of the inverting circuits except the first start inverting circuit and an inverting circuit immediately following the first start inverting circuit is a second start inverting circuit which starts an operation of inverting an input signal in response to a second control signal.

Abstract: A low power clocking circuit includes a crystal oscillator for generating a digital signal having a first frequency. The first frequency is relatively slow which allows the crystal oscillator to consume reduced power. The phase detector signal is coupled to control a charge pump circuit that generates a voltage on an output node for controlling a voltage controlled oscillator. The VCO generates a clock signal having a second frequency that is higher than the first frequency. The charge pump circuit includes an active mode and a power down mode and is operatively coupled between a first supply voltage and a second supply voltage. As typically provided, the charge pump includes a capacitor network coupled to the output node for maintaining the output voltage. The charge pump includes a voltage control circuit having an up input for increasing the output voltage and a down input for decreasing the output voltage.

Abstract: An integrated memory circuit is described which includes a charge pump for producing a pumped voltage and a ring oscillator coupled to the charge pump. The ring oscillator is used to operate the charge pump, such that pump cycles are activated on the edges of the oscillator output. The ring oscillator includes an oscillator enable circuit which is controlled by a regulator to maintain a controlled pump voltage. The oscillator enable circuit immediately shuts the ring oscillator off when the pump voltage reaches a pre-determined upper voltage limit so that additional oscillator cycles are eliminated, thereby, reducing the chance of an overshoot in the pump voltage. The oscillator enable circuit turns the oscillator on when the pump voltage decreases to a predetermined lower level.

Abstract: A relatively simple low-power-dissipation oscillator circuit comprises an inductor in series with a capacitor. Self-timing circuitry connected to an output node point between the inductor and the capacitor compensates for resistive losses in the circuit and thereby insures generation of a constant-amplitude output sine wave suitable for driving PPS CMOS circuitry. The oscillator circuit also includes starting and stopping circuitry connected to the inductor. To conserve power during so-called data inactive periods, the oscillator circuit can be abruptly stopped in a manner that preserves stored states in the CMOS circuitry and provides an output voltage suitable for powering conventional (non-PPS) CMOS circuitry while establishing a reliable basis for subsequently reinitiating oscillations.

Abstract: A semiconductor diode is connected across the cathode-to-anode path of a magnetron and through a storage capacitor and collector resistor to a supply voltage for enabling charging of the capacitor. A control pulse causes a switching transistor to conduct to discharge the capacitor through its collector-to-emitter path, an emitter resistor, and the magnetron, for causing the latter to oscillate. A feedback signal representative of the difference between the magnetron output frequency and a reference frequency is applied to a linear amplifier transistor which conducts through the emitter resistor for controlling the current flow through the switching transistor and the operating frequency of the magnetron.

Abstract: An oscillator is provided for use in integrated circuits of the type that are employed in various, relatively low power, power management systems such as can be found in mobile communications systems and the like. The oscillator provides an output frequency that is highly stable over a range of conventional operational parameters. The oscillator provides a current generator that is comprised of a pair of NMOS transistors and a pair of PMOS transistors that are arranged such that the respective gates of each pair are connected to one another to establish current mirroring. The current generator is connected to a hysteresis circuit, which is operable to develop a potential difference in the circuit. The hysteresis circuit includes an NMOS transistor and a PMOS transistor that are respectively and correspondingly coupled to the current-mirroring NMOS and PMOS transistor pairs of the current generator.

Abstract: A CMOS coupled-tank oscillator for VLSI circuit applications is disclosed. The coupled-tank oscillator has two inverters coupled, input-to-output, by inductances that may be simply wires, and a capacitance acting in parallel with each inverter that may be, simply, the invert's gate capacitance. The invention permits 0.9-micron CMOS oscillators to produce high-frequency signals.

Abstract: A semiconductor integrated circuit includes an oscillator circuit, which amplifies a signal sent from an oscillator by an amplifier circuit operating with a low power supply voltage for outputting the same. In the oscillator circuit, a threshold voltage of a transfer gate forming a switching element is set to a value lower than a threshold voltage of other transistors so as to reduce an on-resistance of the transfer gate and hence to ensure output of a signal supplied from said oscillator.

Abstract: Disclosed herein is an oscillator circuit generating an oscillation signal in response to a resonant element in a first mode and to an external clock signal in a second mode. This oscillator circuit comprises a tri-state inverter circuit and a transfer circuit between the input and output nodes of the tri-state inverter circuit, and the output node of the tri-state inverter circuit is brought into a high impedance condition when an external clock signal is used and into an active state when the resonant element is employed.

Abstract: The voltage-controlled oscillator (VCO) of the present invention is designed with reduced sensitivity to power supply voltage variations. The VCO includes multiple inverter stages with dc supply inputs tied to a filtered control dc signal, and a disabling circuit for disabling oscillation. The disabling circuit includes a disabling gate connected to the input to said inverter stages and an enabling gate connecting to the output of the inverter stages for enabling transmission of output from the VCO.

Abstract: In an electrosurgical generator having a self-tuning oscillator which includes a switching device and a resonant output network connected between the switching device and a supply rail, an oscillator feedback circuit feeds to the switching device a switching control pulse signal for separately switching the switching device to its "on" state whilst the voltage across the device is decreasing, the phase of the "on" point being dynamically variable such that the "on" time of the device is adjusted so as to regulate the amplitude of the voltage thereacross. This allows reverse conduction of the switching device to be avoided, giving improved efficiency.

Abstract: An oscillation circuit includes inversion circuits and delay circuits wherein at least one of the inversion circuits includes multiple inverters connected in series to one another and wherein the driving capability of a first stage inverter inserted immediately after the delay circuit at the input of the oscillation circuit is lower than that of a final stage inverter inserted immediately before the delay circuit at the output of the oscillation circuit.

Abstract: A ring oscillator for circulating pulse edges of two types therein includes an even number of inverting circuits connected in a ring. Each of the inverting circuits is operative to invert an input signal and output an inversion of the input signal. One of the inverting circuits is a first start inverting circuit which starts an operation of inverting an input signal in response to a first control signal applied from an external input. One of the inverting circuits except the first start inverting circuit and an inverting circuit immediately following the first start inverting circuit is a second start inverting circuit which starts an operation of inverting an input signal in response to a second control signal.

Abstract: An integrated voltage controlled oscillator (VCO) circuit which utilizes the relative capacitance ratio between capacitors and the relative resistance ratio between resistors in an integrated circuit (IC) to output a signal having a predictable frequency for a given control signal voltage. The VCO output frequency will not vary more than 3.0% from one IC chip implementing the VCO circuit, to the next. This low variance between IC chips is derived from the phenomenon whereby the respective ratios of capacitance and resistance between capacitors and resistors in the IC will not vary more than .+-.1.5% from the ratios of like capacitors and resistors on other IC chips. The integrated VCO circuit includes a control signal subcircuit, integrator subcircuit, filter subcircuit, and comparator unit subcircuit.

Abstract: In a PLL frequency synthesizer capable of minimizing power consumption in the power saving operation, there are disposed a voltage controlled oscillator, a phase detector, an active filter, a reference frequency oscillator, a dual modulus prescaler, and a pulse swallow counter having a modulus control terminal. In the power saving operation, the modulus control terminal is set to an inactive state by a controller to prevent power of a power source from being supplied via the pulse swallow counter to the dual modulus prescaler.

Abstract: A battery-powered magnetic pen has an oscillator for generating a magnetic field at a contact frequency and a proximity frequency. The oscillator is connected to a resettable timer. The pen also includes a tip switch that is actuated in response to the pen being brought into engagement with an object and disengaged from the object. The tip switch is connected to a pulse generator and to the oscillator. Each time the pen is brought into engagement with an object, the pulse generator resets the timer to initiate the timing of a time out period. Assuming the oscillator is off, the first time the pen contacts an object, the resetting causes the oscillator to be turned on. So long as the oscillator is on, the opening and closing of the tip switch causes the oscillator to switch between the contact frequency and the proximity frequency. Should the timer reach the end of a predetermined time out period, the oscillator is shut off.

Abstract: A phase-lock loop circuit including a voltage-controlled oscillator for generating a clock signal. The voltage-controlled oscillator includes a plurality of multiplexers coupled in series. The signal generated by the last multiplexer in the series is used as a clock signal. Each of the multiplexers in the series has a select input. Either a first signal or a second signal propagates through the series of multiplexers, depending on a select signal applied to the select inputs of the multiplexers. The second signal is the first signal with a predetermined delay. A 3-input multiplexer is connected to the first and last multiplexers in the series to the form a ring oscillator. The first or second signals output by the last multiplexer in the series is sent to an input of the 3-input multiplexer, and a test signal is sent to a third input of the 3-input multiplexer. The 3-input multiplexer also receives the select signal and a test mode signal.

Abstract: A battery-powered, magnetic-pen oscillator includes a circuit having a first transistor arranged in a common emitter configuration. A feedback loop includes a transformer and the transistor that produce a loop phase shift of zero degrees and a loop gain of one to cause oscillation, and additionally creates the magnetic field emitted by the pen. A second transistor provides current mirror biasing for the first transistor and determines the amount of current flowing through the first transistor.

Abstract: A voltage controlled oscillator (VCO) (2) provides an output signal which has a 50% duty cycle and a frequency which depends on the voltage of a control signal (V) supplied thereto. The VCO (2) comprises first (C.sub.L) and second (C.sub.R) capacitors and first (3) and second (5) circuits. Each of the first and second circuits comprises a current supply arrangement (10, 12, 14, or 18, 20, 22) coupled to a respective one of the capacitors (C.sub.L or C.sub.R) and to receive the control signal (V), and a Schmitt trigger (6 or 16) coupled to the respective current supply arrangement and to the other capacitor, which is not coupled to the respective current supply arrangement. Each current supply arrangement of the first and second circuits alternately charges and discharges the respective capacitor, in dependence on the switching of the respective Schmitt trigger, so that the VCO (2) oscillates between the charging of the first and the charging of the second capacitor.

Abstract: A variable reluctance transducer system incorporating digital control of parallel resonant circuits including two inductive sensors L1 and L2 on each side of a flat diaphram. The dual variable reluctance elements provide dual frequency signals for digital calculation to obtain a quotient of the frequencies, thereby substantially eliminating the resonant frequencies as a variable in the accuracy of the device. Manipulation of the produced quotient by a micro-controller 10 employing digital calibration tables stored in a programmable read only memory 14 allows calibration reponsive to a temperature sensor 16, thereby substantially eliminating temperature induced errors in the system, further increasing accuracy.

Abstract: An oscillation inducing circuit includes a power-on circuit connected to a power supply of V.sub.DD, a plurality of transfer gates, and a capacitor. The power-on circuit (1) supplies a control signal having a first level to the transfer gates so that a capacitor is charged in a first polarity direction to an instantaneous level of the increasing power supply voltage, and (2) supplies a control signal having a second level so that the capacitor is charged in a second polarity direction, opposite to the first direction, to a voltage equal to an addition of the previously charged voltage and the present instantaneous power supply voltage. Together, these two charges produce a relatively high voltage for initializing the circuit and starting an oscillator.

Abstract: A source for generating energy in the microwave region to a load comprising a transmission line, a semiconductor switch connected between said transmission and said load, said switch being operable, in its open state, to sustain a voltage corresponding to the average maximum electric field physically sustainable by the switch and, in its closed state, to sustain the maximum current density J equal to Wd.sub.3, where W is the width of the switch and d.sub.3 its thickness to thereby supply maximum power to the load and maximum switching speed.

Abstract: An adjustable output level transmitter includes a direct current energy source, an L-C tank circuit and a switching means for sequentially coupling the capacitors of the tank circuit to the direct current energy source and ground. The output signal frequency is equal to the resonant frequency of the L-C tank circuit and the output signal level is a function of which capacitors of the L-C tank circuit are sequentially coupled to the energy source. The circuit functions in a Class D mode with the inherent advantages of minimal power loss and very high efficiency. Due to the manner of switching utilized, the output signal frequency is very stable and unaffected by the mode of capacitor switching.

Abstract: An oscillation circuit having multiple separately addressable oscillator stages for applying RF voltage across selected capacitive loads where each stage includes a power driver, a transformer and a quench/clamp circuit. The oscillation circuit includes one enablement circuit responsive to an externally applied enablement signal and address signal and a common feedback circuit connected between one end of all of the transformers and the enablement circuit. An externally applied address signal and an enable signal selects a particular oscillator stage and initiates action of a power/driver circuit to provide an initial pulse of AC current through the associated transformer for a preset period and the feedback circuit detects negative zero crossovers of the waveform of current through that transformer primary to maintain actuation of the driver circuit for as long as the external enable signal is present.

Abstract: To excite a resonator so that it oscillates at its resonant frequency, a self-oscillating system is used having a digital delay element (such as a digital memory) or an analog delay element (such as a bucket-brigade device) inserted in a feed-back loop. Detecting the oscillation signal and exciting the resonator is done periodically and alternately. Thus, the oscillation signal is detected while the resonator oscillates freely. In the embodiment disclosed, a coil (1) serves both to detect the oscillation signal and to excite the resonator which is in the form of a string (2). A switch (3) is controlled so as to apply the detected signal to a delay circuit (7) during each first period and to supply the delayed signal as an exciting signal to the coil (1) during each second period.

Abstract: A source for generating microwaves using sequential switching of cascaded TEM transmission lines of arbitrary lengths charged to arbitrary voltages where the delay between any two switches is equal to or greater than the temporal length of the transmission line separating them, the first switch activated being the one closest to the load. The source uses an optimized transmission line and switch geometry which yields the highest possible power flow. Various folded configurations of the source which provides added compactness and simplified energizing are also disclosed.

Abstract: A solid state oscillator which may be used as a microwave electronics teaching aid. The solid state oscillator is powered by a klystron power supply, and is interchangeable with a klystron. The solid state oscillator includes a circuit having inputs, through which a conventional klystron AC filament voltage is inputted. The circuit then rectifies and raises the input voltage to a higher level, and then tunes the higher level DC voltage to a resonant frequency. The raised voltage is powered by a microwave signal by means of a solid state microwave diode mounted in a wave guide.

Abstract: A zero-phase restart circuit that provides a new circuit element in the path of the incoming data signal in order to delay the data signal by an amount equal to the delay caused by the restart circuitry. This ensures that the phase difference between the two signals will be zero at restart and thus effectively cancels out the residual error seen with the prior art. This technique remains effective well into higher data rates. The advantages of the present invention allows the circuit to operate near its limit without suffering large transients on the VCO control voltage and the VCO frequency. The overall system will not be limited by the transient response on the VCO control voltage nor the VCO frequency. It allows for higher operating speeds of data. Further, the new method will allow the system to better tolerate the jitter of the incoming data such that the restrictions on the jitter performance of the incoming data can be reduced substantially, i.e., allow more jitter to exist on the data.

Abstract: A pulse repetition frequency (PRF) pushing compensation circuit to negate PRF-induced frequency shifts and ambient temperature change-induced frequency shifts in pulsed RF sources. The PRF pushing compensation circuit samples PRF voltage and feeds it into a resistor-capacitor (RC) network so that the DC voltage component across the capacitor is directly proportional to the PRF. The DC voltage is then amplified, via a transistor, and fed to a varactor diode circuit coupled to the source's frequency determining element (e.g., dielectric resonator, microwave cavity, or other element). With a varactor diode tuning the source, the capacitor voltage derived from the PRF voltage is applied to the varactor diode to effect a frequency shift in the pulsed RF source which is equal and off-setting to the PRF-induced frequency shift. Temperature sensitive resistors can be used in the DC offset voltage of the varactor diode circuit to compensate for frequency changes due to ambient temperature variances.

Abstract: A stabilized gated oscillator that provides pulses at a predetermined repetition rate in phase coherence with a gating signal includes a ceramic resonator in a feedback resonant circuit between the output terminal and the input terminal of a linear amplifier. The resonant circuit, which establishes the repetition rate, is constructed to provide an oscillator frequency in a frequency range between two resonant frequencies of the ceramic resonator wherein the ceramic resonator acts as an inductance.

Abstract: An oscillator circuit for supplying a gas discharge path. A self-oscillating oscillator is controlled by pulses whose width, amplitude, and/or frequency are regulated as necessary to stabilize the oscillator output power, energy, and/or voltage.

Abstract: A high-frequency power oscillator includes a tetrode electron tube (5), a current source (3) and a voltage-limiting circuit (4). The current source (3) is connected to the screen grid of the tetrode (5). This limits the screen grid current when the voltage on the anode of the tetrode (5) is momentarily lower than the screen grid voltage. Between the screen grid and the cathode of the tetrode the voltage-limiting circuit (4) is inserted. This circuit starts to conduct above a predetermined threshold value. This forms a limit to the screen grid voltage so that is is possible to operate the tetrode (5) in a pulsating manner. The voltage-limiting circuit may comprise a triode (4) with a voltage source (2) providing a constant voltage between the grid and the cathode of the triode (4).

Abstract: A self contained circuit to enable a tank type (coil/capacitor) voltage controlled oscillator to start up and free run from a known state. The circuit allows the oscillator to be stopped to within two periods by invoking its only input logic signal and also restarted with no adverse effects on its free running operation. It includes three current mirrors, one which sets the current for the other two mirrors and of the final two, one actively sets a bias on a coil (stops oscillation) while the other makes up for the lack of coil bias by providing an equivalent amount current influx to the oscillator in the free running condition.

Abstract: A gated oscillator circuit for generating a sampling signal for digitally processing television signals, uses an LC oscillator to achieve, high frequency stability and reduced edge jitter. Circuitry is provided on both sides of a tank circuit in the oscillator for decoupling the tank circuit from other active circuit elements thereby enhancing the frequency stability.

Abstract: A power amplifier driven in the switching mode is started into oscillation by a pulse from an auxiliary oscillator when it is first activated. Reactive currents thereby resulting in an output filter network, containing a series resonant circuit followed by a parallel resonant circuit which is connected across a load impedance, then produce the switching in of a feedback circuit, after which the amplifier oscillates in a self-excited mode, at a frequency determined by the tuning of the resonant circuits.

Abstract: A circuit and method of operation thereof for initiating a fast rise pulse scillator in a projectile fuzing system is less susceptible to external counter measures. The oscillator circuit includes an oscillator transistor which has a step recovery diode connected to the base of the transistor. The step recovery diode is forward biased for storing charge therein and then reverse biased thereby producing an internal transient in a tank circuit, also connected to the base of the transistor, which produces a rapid buildup of oscillations.

Abstract: An oscillator circuit comprising a feedback amplifier circuit having a power supply terminal, a resonant circuit comprising a crystal, and a differential amplifier which is coupled to a bias current source which is switchable stepwise by means of a level detector for the stepped excitation of the resonant circuit from a predetermined potential at the power supply terminal. When switching on the power supply voltage, the level detector insures that the resonance of the oscillator circuit is achieved in a defined and a reproducible way.

Abstract: A frequency set-on oscillator comprises an input switch (12) an amplifier (22) and a delay line (16). A frequency divider (14) having two outputs is provided in line with the input switch (12). The two outputs of the frequency divider are connected to a mixer (20), one of the outputs containing the delay line (16). The output of the mixer (22) is fed to the amplifier (22) and the output of the amplifier is fed back to the input switch (12) via a bandpass filter (24). The device of the invention is a very simple network configuration capable of sustaining a desired frequency for very much longer periods than has been possible with previous devices.