Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [oscillation]

Oscillation refers to the repetitive variation of electrical signals.

Oscillation is the repetitive variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states. In the context of Electrical Engineering, oscillation refers to the repetitive variation of electrical signals.

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How does this old oscillating light board work?

I know EE.SE loves a good treasure hunt, so here's one to noodle on. This device was made in the 1950s or 1960s by a Bell Labs EE. He designed it as a toy to amuse his young son. Said child, now turning 70, has asked a family member (me) how it…
Kenn Sebesta
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Why doesn't LTSpice predict this op-amp oscillation?

I'm developing a circuit to act as an electronic load for bench testing power supplies. An earlier question about how to test this circuit received several very useful answers and can be found here: How to test op amp stability?. This question is…
scanny
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Where do the oscillations on the output voltage of my buck converter come from?

I am currently building a buck converter. Its main parameters are the following: 24V input 5V/3A output Able to sustain large load transient currents caused by the switching of power LEDs (~2A) I selected a synchronous buck converter from TI which…
Bat_AAAAAHHH
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This op-amp buffer is oscillating and I can't figure out why

Currently, this is the only assembled part on the circuit board. This is a simple inverting buffer circuit that should be at the input. The op-amp (LTC6241HV) is powered +/-5V from a linear bench power supply. The power pins are bypassed with 0.1uF…
user733606
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LTspice diode bridge rectifier input oscillating

I've made a LTspice model of a diode bridge rectifier, but when I simulate my circuit, the input voltage is oscillating. Here is my schematic, along with the simulation result of the voltage at node 3 (marked with an arrow.) When I zoom in on these…
Ana Ćupurdija
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What prevents this op-amp reference buffer from oscillating?

I was just perusing the open-source schematic for an ECG amplifier, found here. The schematic contains what I take to be a reference-voltage buffer, with heavy use of capacitive filtering: From what I understand, using an op amp in unity-gain…
davidf2281
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The Intuition for RLC circuits

I'm reading through Hayt's Engineering Circuit Analysis 9e and it does a fairly good job of giving the intuition for "where" the energy is going in a damped RLC circuit, but I'm hoping that someone here can help me get full closure. Consider a…
EE18
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Why does this circuit oscillate?

The circuit below is an oscillator. When I simulate it with ltspice, it does indeed generate a waveform (although it doesn't seem to be a very pure sine wave). What I fail to understand is why it oscillates. All the basic literature I have read so…
blondiepassesby
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Chopper Amplifier feedback loop stability

I have a question regarding the stability of a circuit I plan on building. This is a voltage-controlled current source, with the IN-AMP being used to sense the current through Rsns and provide feedback to the op-amp. I'm trying to use a programmable…
Jordan
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Is it possible for an opamp to oscillate at a frequency greater than its GBP?

I was installing a tl3141 into a headphone amplifier circuit and it appears to break into ~250mVp-p oscillation at 8-10MHz on the lower half of the waveform when fed a 1kHz sine wave. Is that even possible given the specs of the opamp (GBP 1.1MHz,…
Frosty
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Controlling heater with PWM through MOSFET

I'm trying to control a heater coil (resistance ~0.9 Ohm) with PWM using a MOSFET. PWM modulator is based on LM393, MOSFET is IRFR3704 (20V, 60A). If I place 1k resistor in place of heater everything runs fine and waveforms at testpoints CH1 and…
s0me0ne
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Why is this op-amp circuit oscillating?

The 40 dB gain op-amp circuit below oscillates (rail to rail) at around 140 kHz when there is no signal generator driving Vin. With a signal generator driving Vin at 10 mVpp it's fine with signals 15 kHz up to 100 kHz (range of interest). Even at an…
mountainmad
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Oscillating comparator in a discrete DC-DC converter

I am making a boost converter for a Geiger counter, based on the STM8L152 MCU. Here's the circuit: The circuit reaches the correct voltage and consumes only 8 μA, however, there are parasitic oscillations in the comparator output (yellow trace),…
Archimedes
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How to calculate the frequency of oscillation of this low-pass phase shift oscillator?

In the following phase-shift oscillator a low pass network is used instead of a high-pass network. simulate this circuit – Schematic created using CircuitLab Usually the frequency of oscillation for a high pass is given by: $$ f_{oscillation} =…
Physco111
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Turning on a PNP BJT from a discrete signal

Some background, though I'm not sure if it'll be relevant to my question: In my design, I have two power stages, a 1st stage PFC boost converter, and a second stage asymmetric halfbridge (I'm using the NCP1605 and FSFA2100 control ICs, respectively,…
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