Skip to main content

Questions tagged [noise]

Noise is an unwanted disturbance in an electrical signal. This tag is for questions about sources of noise, noise types, issues caused by electrical noise, or improving the signal-to-noise ratio of an analog circuit.

Filter by
Sorted by
Tagged with
1 vote
2 answers
83 views

Is the x-capacitor essential in the circuit below?

hi I hear a buzzing noise from c1 and L1 in this circuit C1 used a film capacitor, not an X capacitor (Film capacitors were used instead of x capacitors because of internal space problems.) I thought ...
 8  minikhh's user avatar
2 votes
1 answer
229 views

10 µF and 0.1 µF capacitors not making any difference in filtering out noise

I have two circuits (green and brown) featuring a load cell, HX711, and ESP32-C3: The HX711 and ESP32-C3 go on top of those round female pin header. The only difference between them is that one is ...
wyc's user avatar
  • 273
0 votes
2 answers
76 views

What should I make of this spectrum analyzer data?

Here I have two signals that I placed into a spectrum analyzer. Channel 1 (yellow) comes from an avalanche photodiode + TIA circuit that has a 50 Ω output resistor, which is directly connected via BNC ...
Collin Fan's user avatar
0 votes
0 answers
32 views

Calculating noise of two resistors in series when one of the resistors has a significant flicker noise component

Two resistors are in series like a voltage divider. One resistor is a very large Vishay TNPW series with no excess noise. Excess noise is defined as noise in excess of the thermal noise due to current ...
BHS's user avatar
  • 145
3 votes
2 answers
382 views

Digital-to-analog-converter PCB: Ground plane cut or not?

I'm designing a DAC board and I'm not sure what would be the best thing to do regarding grounding, to minimize noise. This is the approximate layout I have so far, with the system ground point (also ...
blockworker's user avatar
0 votes
2 answers
110 views

Caps vs. no caps = the same noise?

This is a setup with an ESP32-C3 and HX711. In this oscilloscope reading, there is a 10 μF cap and a 0.1 μF cap across the VCC and GND of the HX711 (it makes the load cell readings more stable). In ...
wyc's user avatar
  • 273
1 vote
2 answers
85 views

Voltage unexpected noise

I'm quite new to the electronic designs so might have made some horrible mistakes in the below circuit. It works as expected but it has a problem. The voltage at the output has some sort of noise ...
Marcin Pluta's user avatar
3 votes
1 answer
72 views

Custom PCB to make a high-precision, low-current voltage source "fix" drift in a lower-precision, high-current current source

I have the following goal, which I presented in a previous question: I'm trying to generate a current source which is extremely low drift but can maintain high current (3A into a few ohms), that ...
Steven Sagona's user avatar
0 votes
1 answer
50 views

Does LISN eliminate differential mode noise?

Do I understand correctly that this LISN circuit doesn't eliminate differential mode noise? And when I get a spectrum, there are two parts of noise: differential mode (DM) and common mode (CM)?
Andr's user avatar
  • 23
1 vote
0 answers
22 views

Sprinkler controller couples electrical noise between stations, firing wrong solenoid

I've been trying to troubleshoot a Toro DDCWP 4 battery-powered sprinkler controller which started exhibiting strange behavior this summer. This is a basic four-station controller paired with RainBrid ...
Luke Soasey's user avatar
1 vote
1 answer
91 views

'Strange' behaviour due to DC motor

TLD: How do I minimise noise / electrical disruptions created by a DC motor? Situation I would like to control a DC motor through DMX512. Therefore I connected a Max485 chip to an Arduino to receive ...
Qwertis's user avatar
  • 21
0 votes
1 answer
48 views

Filter for supply voltage of amplifiers

I need to design an ultra low noise amplifier in transimpedance architecture. This is the architecture I have chosen: In addition to the decoupling capacitors on the supply pin I have also added two ...
Andromeda's user avatar
  • 491
0 votes
2 answers
79 views

Issues with Audio Amplifier Circuit - No Output Signal with Capacitor, noise

I'm having trouble with an audio amplifier circuit that I designed, and I hope someone can help me figure out what's wrong. Here's the schematic of my circuit: Rsig is a variable resistor The circuit ...
CHIEN LE's user avatar
0 votes
0 answers
78 views

Persistent ripple at the buck converter output

I developed a half-bridge buck converter, I did all the steps, from the converter calculations, such as accommodating the copper in the appropriate ferrite core, wire gauge diameter, etc., my project ...
ever_pi's user avatar
  • 41
0 votes
0 answers
29 views

How to work with UART to make communication between stm32 and hmi nextion display in noisy environment?

in an ultrasonic generator project, I am using an STM32F334 microcontroller as the main controller and an HMI Nextion display (model NX8048T070) that includes another STM32 for driving the monitor. I ...
Mahdi Javidnasab's user avatar
0 votes
0 answers
34 views

Noise Figure at the Rx ADC output

I need to measure gain & nf of the Rx at the ADC output. I inject sine wave tone to the Rx input. Then I make a ram dump of the IF ADC output, read it, perform fft and finally get the IF PSD. My ...
testdriver87's user avatar
0 votes
0 answers
56 views

Power supply issues for poor man's SONOFF

So I have zero electronics education. I've created some devices just following YouTube videos and what I call a bit of common sense. Long story, but basically found that I could purchase D1 Mini's (...
Cancun Manny's user avatar
1 vote
1 answer
94 views

Ground loop issue with Raspberry Pi and amplifier board

I'm trying to run a Raspberry Pi with a USB audio adaptor into an external amplifier board via 3.5mm, then running out to speakers from the amp. Right now I'm getting a lot of electronic noise coming ...
youcloudsofdoom's user avatar
1 vote
3 answers
94 views

Can a high-precision, low-current voltage source "fix" drift in a lower-precision, high-current current source?

I'm trying to generate a current source which is extremely low drift but can maintain high current (3A into a few ohms), that should be similar to this expensive high-precision current source. However,...
Steven Sagona's user avatar
1 vote
0 answers
22 views

EFT (IEC 61000-4-4:Burst Test) Fail. I used SPI Interface [closed]

I am using TI ADC part# ADS131E08 and STM MCU Part# STM32H7 Series. #3 channel : Voltage measurement (3phase) #3 channel : Current measurement (3phase) #1 chanel : Internal-zero current measurement. #...
DSKIM's user avatar
  • 11
2 votes
0 answers
34 views

Question re: layout and grounding of a PCB with SPI-controlled H-bridges and load switches

My question is regarding the layout, and in particular the grounding, of a PCB that has a microcontroller that controls various H-bridge drivers (that will be PWM’d) and load switches via SPI. The ...
Mark512's user avatar
  • 21
0 votes
1 answer
74 views

Noise in ADC PIN

for signal conditioning before feeding it to the ADC of a microcontroller, I have the circuit shown in the image below. The 12V comes from an external source, and my goal is to measure this voltage ...
Anthony Maisincho's user avatar
0 votes
0 answers
51 views

Periodic Voltage and Current Fluctuations in Autonomous Robot System

I have an autonomous robot system powered by a 24V LiFePO4 battery that has several distributed PCBA's getting their power from the 24V battery, and also having their own on-board DC-DC buck ...
Sam's user avatar
  • 1
0 votes
0 answers
33 views

PCB Power and Ground planes Setup [duplicate]

When designing a 2-layer PCB, I've read that ground planes are good to reduce noise and to provide a stable-ish ground reference when a board isn't connected to a chassis, ground etc. If I need to ...
Steam Ranger's user avatar
0 votes
0 answers
44 views

Noise added by an amplifier when deriving Friis's formula

I have been asked to derive the equivalent noise factor for a cascaded system of two amplifiers. Here is the figure of the system (assuming a general configuration where \$ G_1 \$ and \$ G_2 \$ are ...
sandun herath's user avatar
1 vote
1 answer
49 views

Noise in classical quantum transmission

In classical quantum transmission, we introduced a scattering model that includes two components: free projection and collision Now, in this figure, this model is introduced that when it goes up in ...
Sajadi's user avatar
  • 145
1 vote
0 answers
35 views

Output Noise of MOSFET with parallel current source

How can I calculate output noise voltage of the given circuit? Noise contribution of the M1 to output noise current: $$4kT\delta g_{m1}$$ Noise contribution of the RG to output noise current: $$4kTR_G[...
Aldrich Taylor's user avatar
1 vote
1 answer
43 views

TDM signals crossing

I'm working on a 2-layer PCB design and trying to do the best I can for signal integrity. I have 2 TDM lines and at a certain point they cross between each other. See image below. Is this likely to ...
Emerson's user avatar
  • 423
2 votes
1 answer
84 views

Proof showing thermal noise of 2 resistors in series behave as a single noisy resistor

For the second part of this question, I came up with two slightly different answers? I believe it's the second one however I am not too sure which one would be the correct one. First one: Second one: ...
zoghii's user avatar
  • 177
0 votes
1 answer
76 views

Mains hum in TDA7265-based active loudspeaker

The old pair of M-Audio Studiophile AV40 active speakers (one box containing all the amplifier parts and the second is just a passive box) I have have developed a clear low-frequency hum. This hum is ...
paulus's user avatar
  • 1
0 votes
1 answer
59 views

what is the source of this noise when recording to raspberry pi using USB soundcard

I connect aux out from my laptop to USB soundcard mic in and use arecord to record audio. But I am getting noise even recording at CD quality. The nature of the noise is really strange as it seems to ...
Vrisk's user avatar
  • 376
3 votes
1 answer
117 views

Choosing Y-capacitor value for isolated DC-DC

In an isolated DC-DC converter datasheet (link), the Y-capacitor recommended is 270 pF. How is this value arrived at? And would the intended use of the Y-cap be achieved if a higher value like 1nF is ...
EarthLord's user avatar
  • 597
1 vote
1 answer
103 views

Differential Amplifier Output Ringing

I designed this circuit. It is a fully differential amplifier of gain one. I am getting this ringing and noise on the output of tx1_o Blue is where the probe is and ground is on circuit's ground. Here ...
Ishmael's user avatar
  • 11
0 votes
0 answers
26 views

ESP32 rebooting on gpio LOW

I am using esp32-wroom-32 module to turn on/off the 24v electronic solenoid valve using 5v relay. Detailed circuit is shown in the image below. However according to my observation whenever the ...
java bee's user avatar
1 vote
3 answers
173 views

When compared to single-ended signals, do differential signals actually offer better EMI protection?

I'm looking for clarification on whether differential signals actually offer benefits with regards to EMI protection versus single-ended signals. Here is my current understanding (feel free to make ...
Izzo's user avatar
  • 2,036
0 votes
0 answers
69 views

Noise in audio amplifiers when touching the smartphone touchscreen as an audio source

While observing the audio output of my smartphone on the oscilloscope, I noticed a signal being generated when I touch the touchscreen. This signal is around 500Hz and appears in groups of 3 peaks, ...
boromyr's user avatar
  • 53
0 votes
0 answers
21 views

TPS61088RHL high ripple noise on normal operation

I have been working with one project which require 12 V power supply with at least 1.5 A current. I used TI Webench power designer tool to create simple 5-10 V input and 12 V 2 A output design. Since ...
Dominykas's user avatar
  • 433
0 votes
1 answer
63 views

Spectrum analyzer bandwidth and noise floor

I have a DUT to measure on a spectrum analyzer. The noise floor is -100 dbm. My signal has a bandwidth of 10mhz. I want to measure the amplitude of my signal and I measure the signal amplitude to be ...
user4434's user avatar
  • 159
0 votes
1 answer
49 views

A-Weighted Noise Power Calculation

Can anyone please show me how to calculate the A-weighted noise power of a noise source. Consider the case of a resistor having a spectral density of 4kTR. What is the A-weighted noise power of this ...
Kenlucius's user avatar
  • 179
0 votes
1 answer
77 views

What could the strange noise in the images be due to? They appear to be composed of 8x8 squares, and many of them contain different patterns [closed]

The question may seem silly, but I am curious about the structure of images from a certain biomedical image dataset. If you enlarge the following image fragments, you can see that they consist of 8x8 ...
forest-spells's user avatar
0 votes
0 answers
38 views

Operation amplifier optimized layout- Noise- Signal Integrity

I was watching a seminar from Fedevel academy, in this seminar as all the datasheet has mentioned, we need to remove GND and PWR plane underneath the negative inverting pin and the output pin of the ...
Andromeda's user avatar
  • 491
1 vote
1 answer
36 views

How can initial switching artifact lift the entire noise floor?

This switching artifacts occur at first data points. Why does it lift the entire noise floor? Is it because all the frequencies in the white noise got amplitude? or only lower frequencies which is ...
Jtl's user avatar
  • 847
2 votes
1 answer
57 views

How can I shield electronic devices against interference from a plasma cutter? [closed]

I am trying to build an NC plasma cutter with a 3D printer. This was the setup: To do some tests I've mounted the plasma torch (Parkside) to the printer's (Creality CR-10) carriage. The button on the ...
big_bear's user avatar
6 votes
3 answers
280 views

Problem implementing a voltage divider with a buffer amplifier

I'm currently working on a project where I need to implement a voltage divider followed by a buffer amplifier to scale down a voltage signal by a factor of ~10. However, I'm encountering some issues ...
LeCarthique's user avatar
0 votes
2 answers
109 views

Reflection on PCB + antenna

I have a transducer with 64 outputs. I want to have 3 of the outputs on my amplifier input in a way that I can choose between them. My first idea for implementing this was to use jumpers as follows: ...
Andromeda's user avatar
  • 491
0 votes
2 answers
55 views

Plotting signal to noise ration (SNR) in SPICE softwares

I want to plot SNR in TINA TI software, do you have an idea how can I plot do it? In this software I just have access to total noise plot and data as follows: (what would be the relationship between ...
Andromeda's user avatar
  • 491
1 vote
1 answer
71 views

Negative offset voltage on analog input in data acquisition device (DAQ) connected to a photodiode in the dark

I have a data acquisition device (DAQ): USB-6002 from National Instruments (NI). I am recording an analog voltage from a (cathode-grounded) photodiode through a variable resistance (50-100k Ohms). I ...
Omnistic's user avatar
0 votes
1 answer
66 views

STM32 SWD Debug Hangs

I try to debug my PCB, which has STM32G030, with SWD in a 3kHz noisy environment. SWCLK and SWDIO traces have both 22 Ohms series and 10k Ohms pull-up resistors attached to them. As the noise source ...
Semih's user avatar
  • 67
0 votes
1 answer
31 views

Voltage reference 1/f noise datasheet comparison

I would like to compare the 1/f noise of the voltage references LT1021 and LTC6655. The LTC6655 has a spec of 0.25 ppm (0.1-10Hz) and the LT1021 has 3uV_pp (0.1-10Hz). I assume these datasheet ...
Stefan Wyss's user avatar
  • 7,653
2 votes
3 answers
801 views

Noise density in 1/f region

The datasheet of the ADR1000 voltage reference specifies the 1/f noise density as 30nV/sqrt(Hz) at 10Hz and 300nV/sqrt(Hz) at 0.1Hz. Given that this is the 1/f region of the voltage reference, how can ...
Stefan Wyss's user avatar
  • 7,653

1
2 3 4 5
43