Relaxation oscillator

About: Relaxation oscillator is a research topic. Over the lifetime, 1952 publications have been published within this topic receiving 22326 citations.

Temperature Measurement in Thermogravimetry

Abstract: A method is described whereby the temperature of a sample in a thermobalance may be determined directly without the large uncertainty that usually accompanies these measurements. The procedure consists of using a unijunction transistor relaxation oscillator with a thermistor as the resistive part. The entire primary circuit including the power supply is made part of the balance suspension and is weighed along with the sample. The frequency of oscillation which is a function of sample temperature is relayed to an events‐per‐unit‐time meter via a mutual inductance between two suspended coils. The nonlinearity of the thermistor is removed to a considerable extent by a compensating circuit.

Oil burner spark ignition system

Abstract: AN OIL BURNER IGNITION SYSTEM PRODUCES A TONGUE-LIKE CONFIGURATION OF INDIVIDUAL SPARKS EXTENDING FROM A PAIR OF DISCHARGE ELECTRODES AND INTO THE SPRAY PATTERN OF OIL PARTICLES PRODUCED BY THE BURNER NOZZLE. THE SYSTEM INCLUDES A SPARK GENERATING RELAXATION OSCILLATOR CIRCUIT CAPABLE OF PRODUCING INDIVIDUAL SPARKS AT A FREQUENCY SUCH THAT SUBSEQUENT SPARKS ARE ABLE TO FOLLOW THE ELONGATING IONIZED AIR PATH ESTABLISHED BY PREVIOUS SPARKS. THE OSCILLATOR CIRCUIT INCLUDES A CAPACITOR CHARGED FROM AN AC POWER SOURCE AND REPTITIVELY DISCHARGED DURING ALTERNATE HALF CYCLES AT RAPID INTERVALS THROUGH THE PRIMARY WINDING OF A TRANSFORMER BY MEANS OF A CONTROLLED RECTIFIER GATED IN ACCORDANCE WITH THE CAPACITOR CHARGE LEVEL.

Relaxation oscillator having a supply voltage independent output frequency

Abstract: Techniques and architectures corresponding to relaxation oscillators having output frequencies that are supply voltage independent are described. In a particular embodiment, an apparatus includes a relaxation oscillator having one or more capacitors and a compensation current circuit coupled to the relaxation oscillator. The compensation current circuit is configured to regulate current provided to the one or more capacitors of the relaxation oscillator in response to changes in a supply voltage provided to the compensation current circuit and to the relaxation oscillator.

Recording and indicating system particularly for locomotives and the like

Abstract: A system for providing signals indicative of the instantaneous power output and the time integral of power output in both analog and digital form. The analog signal indicative of the instantaneous power output is obtained by providing a switchcontrolling digital signal whose frequency is linearly proportional to the instantaneous amplitude of the voltage applied to the d.c. traction motor and whose pulse durations are of fixed value. The controlled switch is normally closed and is connected in shunt with an averaging circuit so that the switch normally short circuits the averaging circuit and provides a path for a current source whose output is linearly proportional to the current supplied to the motor. The averaging circuit, which includes a d.c. current meter, sees a digital signal whose frequency is modulated according to the supplied voltage and whose amplitude is modulated according to the instantaneous current. An integrating capacitor in the averaging circuit drive a relaxation oscillator to provide a digital signal whose frequency is linearly proportional to the instantaneous power so that integration of this signal yields an indication of powerhours. An improved amplifier particularly suitable for accurate amplification of small signals is provided also.

Phase-locked loop with capacitive voltage divider for reducing jitter

Abstract: In a phase-locked loop comprising a phase detector (1), a loop filter (5) and a controlled oscillator (17) which are arranged on a common integrated circuit, interferences coupled into the substrate of the integrated circuit by other parts of the circuit are suppressed. In a first embodiment of the invention, this object is achieved in that the controlled oscillator (17) is preceded by a capacitive voltage divider (9) which comprises at least two capacitances (10, 12), the controlled oscillator (17) is controlled in dependence upon the output signal of the capacitive voltage divider (9), and the capacitive voltage divider (9), together with the phase detector (1), the loop filter (5) and the controlled oscillator (17) is arranged on an integrated circuit. In accordance with a second embodiment of the invention, the reduction of interference is achieved in that the controlled oscillator (17) has a differential structure and comprises at least two voltage-controlled current sources (18, 19) whose circuits are coupled to a power supply potential and to a substrate on which the integrated circuit is arranged, the controlled oscillator (17) has an output stage (20) which is arranged behind the voltage-controlled current sources (18, 19) and generates two differential digital signals in dependence upon the differential signals applied thereto, which differential digital signals are generated with a high edge steepness by means of switching between two potentials and are applied to amplifier stages (56, 57) which are arranged between power supply potential and reference potential and supply two differential output signals operating at reference potential.