Questions tagged [capacitors]
A device used to store an electric charge, consisting of one or more pairs of conductors separated by an insulator.
24
questions
-1
votes
1answer
35 views
Insufficient force from 6v 1A push-pull solenoid powered by a stepped down 9v battery (relay) to be used as a kicker, why and what can be done? [closed]
I am powering a 6v 1A push-pull solenoid (https://www.tinytronics.nl/shop/en/robotics/accessories/solenoid-push-pull-6v-300ma-jf-0530b) using a 9v rechargable battery using a relay; the 9v is stepped ...
1
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0answers
46 views
Debouncing interrupt using capacitor
I'm currently working on nodeMCU and need to use interrupt pin. I find out there are bouncing problem when using interrupt thus i use capacitor 100uF to solve this problem. The question is by using ...
2
votes
1answer
59 views
Arduino Mega Clone CH340G Capacitor Values
I'm making my own Arduino Mega board with ATmega2560-16AU and CH340G. Jump to the end of the post to find the real question.
I have already ordered a PCB before and it didn't work when I soldered ...
2
votes
2answers
69 views
How safely write to SD or Eeprom on Arduino power off
I want to constantly store data to sd. But how I make sure data is not corrupted on moment of power off? I think I could add small capacitor on 5V and check when voltage drops, so I would stop data ...
2
votes
0answers
70 views
Reliably using analogRead as a compact digitalRead
My goal is to reduce pins being used for micro-controllers with limited pins, or projects requiring a few different digital input values.
How I intend to do so is by using ADC pins to gather four ...
0
votes
1answer
43 views
USB disconnects when using a capacitor
I'm currently working with some WS2812B LEDs and tried out adding a capacitor to be safe from voltage spikes (was recommended by Adafruit). I noticed that a soon as I connect a capacitor between 5V ...
0
votes
1answer
171 views
Placing decoupling capacitors when building an Arduino PCB with Atmega328-PU
I have previously asked this question:
Custom build of arduino on a pcb
And thanks to the answer by Majenco I have learned that my circuit works a lot better when adding a capacitor. For example I ...
0
votes
1answer
74 views
Please help me read this Schematic Diagram
So, i'm trying to build an Obstacle Avoiding Robot by refering this site "Robot Obstacle Avoiding Car
On the website they have provided with very poor Circuit Diagram.
Please help me read the ...
-3
votes
1answer
129 views
Serial communication stops when powered with batteries?
Circuit explanation-
Arduino Uno connected to multiple sensors and to 16 x 2 LCD.
Uno's TX pin to ESP-01 RX pin.
Uno has been programmed to read values from sensors and display them on LCD along ...
0
votes
2answers
231 views
How to safely remove arduino nano from breadboard? [closed]
I did some prototyping with arduino nano in breadboard. And then after i done with the design, I was gonna implement it in a printed pcb so i need to remove the nano from breadboard. And this is when ...
-2
votes
1answer
283 views
What should the cut-off frequency be? [closed]
To convert a PWM signal to a DC voltage it must be filtered with a low pass filter. How can you know which cut-off frequency should be used and how do you calculate the values for the resistor and ...
4
votes
2answers
2k views
Why is AREF connected to a capacitor in the Arduino Pro Mini Schematic?
I'm currently looking at the Arduino Pro Mini schematic and have noticed that the pin AREF (analogue reference) is connected to a 0.1uF capacitor as shown below:
I have done some research and read ...
0
votes
0answers
161 views
Testing a capacitor with a nodeMUC Lolin V3
Apparently it's possible to test the capacitance of a capacitor with an arduino. In this thread, someone tries to do the same on a NodeMCU but the conclusion is that it's enough to get the change in ...
0
votes
1answer
97 views
How would I go about powering addressable RGB LED light strip? [Arduino Nano] [closed]
The addressable RGB LED I have is WS2812B. I plan on controlling the LEDs via an Arduino nano. I have a total of 188 LEDs to supply power to.
Would I require anything between the addressable RGB LED ...
0
votes
1answer
158 views
How can I power a NeoPixel ring and strip through Arduino MKR1000?
I currently have a MKR1000 which is connected to 1 ring with 8 neopixels, 1 strip with 20 neopixels, 1 microwave sensor, 1 speaker, 1 rotary encoder. I am running the NeoPixel positive and negatives ...
0
votes
1answer
263 views
Capacitors, Arduinos and Saving Data
In short, I have programmed and wired a speed/odometer and all is working well. However, I need to save data from the components/sensors once a power button is pressed, which has led me down the road ...
0
votes
1answer
2k views
How to keep a pin LOW for a small amount of time after pushing a button and while device is booting?
Context
I keep the board in deepsleep mode and want to wake it with different buttons. I need to know which button has been pushed on boot. The board is immediately put back in deepsleep mode ...
0
votes
1answer
2k views
Reading values from TTP229 capacitive touch sensor on arduino
I would like to be able to read the raw capacitive sensor values from a TTP229 chip through i2c in Arduino. I have one of these breakout boards to play with :
My goal is to get values similar to ...
4
votes
4answers
2k views
Is the ShiftOut tutorial on the official Arduino website really wrong regarding the capacitor?
I'm talking about this tutorial "Serial to Parallel Shifting-Out with a 74HC595" from the official Arduino website. It provides the following schematic:
I've read a couple of times now, that the ...
1
vote
2answers
2k views
Purpose of capacitors in this project
I'm currently working on a project where I am making a wheeled robot using the Hack-e-bot library on the arduino. The circuit board which I have planned to put together through soldering will ...
1
vote
1answer
345 views
Decoupling cap for self-powered LED matrix and LED strip
Should I add a decoupling capacitor to my RGB 16x32 LED matrix powered directly via the 5V pin?
When I display a spectrogram, the current load is fluctuating quickly in the 100-250 mA range (on ...
1
vote
1answer
265 views
PWM water pump flow control - should I use capacitor for MOSFET? [closed]
I want to control flow level on 12V water pump with PWM pin, I'm using IRF520N MOSFET for that (and dedicated 12V power supply).
Should I use some capacitor on MOSFET output to "smoothen" voltage? ...
1
vote
2answers
3k views
Correct Capacitors to use with L7805 Voltage Regulator
I am making my own arduino. I am in the process of hooking up power to the Atmega328.
In both these articles they use the L7805 voltage regulator with two 10uF capacitors.
https://www.arduino.cc/en/...
0
votes
1answer
173 views
Resistors/capacitor used in connecting 23LC1024 SRAM 1 Mbit
Yesterday I received by 23LC1024 SRAM with 1 Mbit memory.
I tried to search for some libraries and ways how to connect it.
So I searched around on internet first for the connections and saw some ...
