Relaxation oscillator

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

Scanning current generator

Abstract: This invention relates to sawvtooth wave generators and particularly to relaxation oscillators capable of producing saw-tooth current waves for use in conjunction with eletromagnetic deflection systems for cathode ray tubes. In one form of cathode ray tube used in oscilloscopes, television...

A 24MHz Relaxation Oscillator Using Single Current Mode Comparator with ±1.67% Drift from -40°C to +175°C for Automotive Sensor Application

Abstract: This paper presents a 24MHz RC on-chip relaxation oscillator with single current mode comparator for automotive sensor application. This oscillator implements only one high speed comparator operating in current mode and a local reference voltage to control the charging process. The frequency trimming is executed at room temperature to constrain process and mismatch impacts. Duty cycle deviation is attenuated as low as possible since identical hardware is reused between current and following period. The power supply rejection (PSR) is improved by a local regulator and a RC filter separately. The proposed design is fabricated in 0.18-μm CMOS technology. The oscillator analog core consumes 100μA at 3.3V power supply. The measurement results show that a stable output frequency is created as 24MHz after trimming with ±1.67% deviation from -40°C to 175°C. The supply voltage ranges from 1.8V to 3.6V.

Power voltage reduction compensating circuit for oscillator

Abstract: PROBLEM TO BE SOLVED: To provide a power voltage reduction compensating circuit capable of maintaining the operation of an oscillator with a sufficient margin even when a battery voltage is lowered. SOLUTION: In this circuit, a switch 3 is inserted in series between a power source terminal Vcc of an oscillator 1 and a positive voltage terminal (+) of a battery 2, a resistor R1, a capacitor C1 and the serial connection of the cathode of a diode D1 and the anode of a diode D2 are inserted in parallel between a negative voltage terminal (-) of the battery 2 and a ground terminal GND of the oscillator 1, further a hybrid transformer 4 is inserted between the output of the oscillator 1 and a signal output terminal and the branch output of the hybrid transformer 4 is connected through a capacitor C2 to the node of the cathode of the diode D1 and the anode of the diode D2. Besides, a circuit composed of the resistor R1, the capacitors C1 and C2 and the diodes D1 and D2 is a negative voltage generating circuit 5.

Frequency stabilization for lsa oscillator

Abstract: To compensate for changes in the output frequency of an LSA mode oscillator, the bias voltage pulse applied to the oscillator is varied by means of a feedback circuit. The output of a high or low pass filter receiving the oscillator RF output is retified to trigger a monostable multivibrator. In an advantageous technique, the pulse output of the multivibrator is integrated, amplified and applied to a Zener diode which is connected to the bias voltage input of the oscillator to provide a clipping voltage to the oscillator responsive to changes in the RF output. A constant voltage is applied to the integrator along with the monostable output to prevent low repetition rates of the multivibrator from introducing a significant AC component in the integrator output. Different rates of convergence are provided in the feedback loop by employing a monostable multivibrator whose output pulse width is controlled by an RF discriminator circuit. To determine more precisely the frequency at which the multivibrator is triggered, a differential amplifier system is added to compare the power in the filter output with the power in the unfiltered RF output.

Photon energy detector generating signal in which durations of first and second half cycles are responsive to photon energy and diode continuity respectively

Abstract: A relaxation oscillator produces a cyclical output signal having alternate first and second half cycles. The oscillator includes a timing circuit having a resistance-capacitance network. The resistance includes a PIN photo diode which exhibits a reverse leakage current responsive to the photon energy incident upon the diode. The photo diode defines the duration of the first half cycles as a function of the reverse leakage current of the diode and defines the duration of the second half cycles as a function of the forward drive current of the diode. The first and second half cycles of the output signal are averaged to provide an output level having a magnitude which is responsive to the photon energy incident upon the photo diode and is responsive to the continuity of the photo diode.