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Questions tagged [resistor]

Passive electronic component which reduces current flow in a circuit, dissipating power as heat.

2
votes
1answer
55 views

How can I tell the resistance of an internal pull-up resistor?

I have a SparkFun ESP8266 Thing Dev board, to which I want to perform a digitalRead() on one of the GPIO ports. I'm using D15, and I'm configuring it for input like this pinMode(15, INPUT_PULLUP); ...
0
votes
0answers
27 views

What happens when using a different resistor? [duplicate]

I want to do this project which calls for a 220Ω resistor. It's pretty basic, controlling an LED with a Bluetooth. I have 100Ω and 330Ω resistors. What would happen if I used either of those? Would ...
3
votes
2answers
74 views

Resistors on LCD - does a small difference matter?

I recently have tried to connect an LCD to my Arduino Uno. The tutorial tells me I need a 220 Ohm resistor, but the only ones I have are 330 Ohm. Does it matter? Here's the Fritzing diagram by the ...
0
votes
1answer
88 views

Pulse counter to measure flow-rate: 0 Pulse issues

I am using a Netafim M-Series flow meter interfaced with a UC-32 Arduino. The goal of this is to create a pulse counter than in turn will allow us to determine flow rate in the meter. (1 US gallon per ...
0
votes
2answers
35 views

Schematic interpretation, where to put resister?

I'm new to schematics, trying to figure out where to put a resistor (no instructions other than the schematic) I'm told I need: 10K variable Resistor x 1, 4.7K Resistor x 1, 100 Resistor x 1 But I ...
0
votes
1answer
38 views

Does blinking an LED with no resistor for a few seconds harm my Arduino?

I am new to Arduino and I just made my first LED blink. I connected the LED to ground and digital pin 13 without resistance (for only a few seconds). Does this harm my Arduino? Hilmi
0
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2answers
174 views

Minimum value I2C-pull up resistor for arduino

I'm trying to determine the minimum value of pull resistor for Arduino Uno The datasheets says for arduino; VOL = 0,4 for IOL = 20 mA. (VDD = 5V) For formula for calculation of minimal pull-up is: ...
-1
votes
1answer
78 views

Minimum value of a pull-down resistor

I've just started working with the Arduino UNO SMD edition and I'm also quiet new to electronics in general. Recently I wanted to try out this tutorial https://www.arduino.cc/en/Tutorial/Button and I ...
0
votes
1answer
25 views

Button isn't working properly

I am new in arduino trying to make race game. My problem is that my button (all buttons) is working sometimes and sometimes not. I am pretty sure that it's because of my code. Could you please help me ...
0
votes
1answer
43 views

Coding force sensitive resistor to give output based on time used?

I have a basic set up of having a force sensitive resistor being used to power an LED as can be seen below. I am wondering how I can code it so that the LED is lit after a pressure has been applied to ...
2
votes
1answer
2k views

Resistor pull-ups for ESP8266

I'm using 4.7kOhm resistor as pullups for GPIOs 2,0,2,16, CH_PD and RESET, and also 4.7kOhm pulldown for GPIO 15. The ESP8266 boots and works fine. Would it be okay for a long shot? Should I use ...
2
votes
3answers
98 views

What is the most Inputs on An analog Pin with a specified Accuracy on the Resistors Used?

I am asking about the technique were switches and resistors in series are used on the analog pin, so it creates a voltage divider when one of the switches is pressed, it a well known technique it is ...
0
votes
0answers
81 views

Arduino IR Transmitter Range Issue

After great struggle, I have finally got IR transmitter working. As first step I was trying to Switch TV Off and it worked. But the issue is that it only works approx. 5 cm away from the TV only. How ...
0
votes
1answer
187 views

4-20 milliamp to volts to pressure maths

I am measuring pressure in bars from OsiSense™ XMLP pressure sensor (4-20 milliamp) on a arduino uno. When the machine im measuring pressure on is switched off the reading is 0v as expected. When the ...
0
votes
1answer
45 views

Powering arduino sensors - what resistor should I use?

Recently I have asked a question, why my sensors do not work on external power supply (link). I have found out, that I was limiting the current too much with the resistors. I have tried using two ...
0
votes
1answer
3k views

Reading 4 to 20ma pressure sensor using uno

I have a OsiSense™ XMLP pressure sensor that I want to read from my Arduino uno. This is the circuit I am looking at building for measure 4 to 20 milliamp. I've read online to find out how to build ...
0
votes
1answer
106 views

In a circuit with a switch and a pull-down resistor, why does the high impedance of the input not discourage current from flowing into pin?

I'm a beginner to Arduino and circuits. I've spent the last couple hours hung up on the concept of how current flows through switches and pull-down resistors, having read every thread and watched ...
0
votes
0answers
817 views

Using Capacitive Sensing Library with a 74HC4067 multiplexer

I'm trying to use the Capacitive Sensing Library by Paul Badger in conjunction with one or more 74HC4067 multiplexers to achieve a lot of capacitive touch inputs. I came across this youtube video ...
2
votes
2answers
2k views

Purpose of this resistor in Arduino Nano schematic

I was looking at the Arduino Nano's schematic and noticed a resistor that seems to be pointless (RP2C on this picture). Also there is numbers 6 and 3 on it, does it mean that resistor is connected to ...
0
votes
1answer
164 views

How do I pull up D1-D6 using 10k ohm resistors?

I'm using push buttons to control CR servos (button1=turn CW; button2=turn CCW). How do I pull up D1-D6 and what does that do exactly? I can't find a tutorial that explains it well enough how to use ...
2
votes
2answers
1k views

8Ω speaker, what resistor values to use?

I want to connect 2 speakers of 8 ohm to 2 (different) pins of the Arduino. However, for this example one speaker is enough. I came across a lot of circuits without or with a single resistor which on ...
1
vote
3answers
2k views

How to select which resistor is required for my curcuit to reduce voltage

I am trying to connect arduino and esp8266 as like this I know arduino runs at 5V and RX of ESP8266 should not have voltage more than 3.5V. If you see my diagram there voltage is large than need on ...
-1
votes
1answer
532 views

Understanding schematics: resistors attached to Attiny85 pins V-USB

I'm currently trying to create my own Attiny85 usb thumb(to mimic an joystick). I understand that I have to limit the voltage on the attiny's pins that are connected to the D+/- pins from the usb. In ...
1
vote
1answer
94 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 ...
3
votes
3answers
4k views

What difference makes resistance of thermistors?

Following this thermistor tutorial i used 1k thermistors (and resistors) instead of 100k as in video. What difference does it make? What about 10k thermistors? Is it good idea to use 1k/10k/100k ...
2
votes
5answers
5k views

Stop Led's from blinking

My code: // Pin 13 has a LED connected on most Arduino boards. // give it a name: int led = 13; const int buttonPin = 2; // the setup routine runs once when you press reset: void setup() { // ...
3
votes
2answers
588 views

Newbie Arduino DC motor problem

So I am new to Arduino and new to electronics in general. I've looked up a few tutorials and they all have a simple early tutorial that turns on a DC motor and turns it off again. Something like this: ...
0
votes
1answer
38 views

Arduino Starter Kit - firmly wiring longer parts

I am getting started with project 01 on the Arduino starter kit. I'm facing an issue when wiring parts with long ends e.g. led & resistor. To make the simple circuit with led, resistor & ...
2
votes
1answer
103 views

What is micro C in a circuit diagram?

This is probably a simple question but I am a beginner with these things. What does the micro C part of the circuit diagram mean? The diagram is from the datasheet of the tssp77038 IR receiver. Does ...
4
votes
1answer
317 views

Getting the DS18B20 detected and temperature read

I'm quite new with the electronics part of Arduino, but I thought that this was the basic way to get the DS18B20 temperature device hooked up. However, I can't detect it in my program using OneWire ...
1
vote
0answers
203 views

How to use Honeywell NBP Series Sensor with Arduino

I am trying to use HONEYWELL NBPDANN100PAUNV Pressure Sensor. I found a example here http://www.circuitstoday.com/interfacing-pressure-sensor-arduino As this example says as instrumentation ...
3
votes
3answers
172 views

Unexpected Delay Between For Loops

I made some arduino code for leds that blink down a row and then back again, but when the program is run, there is an approximately 2 second delay in between the first for loop and the second. This is ...
1
vote
1answer
559 views

Formula for current through shift register

Hi I am programmer that just started learning electronics and Arduino. I built this simple circuit on Autodesk Circuits earlier. Originally I used 220 ohm resistors. Then when I ran the simulation ...
0
votes
1answer
45 views

Switch between ntc resistor sensors time based for other device

We have a heating system that uses an ntc resistor to measure water temperature. I would like to replace that ntc resistor by a fixed one (low enough to disable heating) temporary on a 5 minute ...
0
votes
2answers
771 views

Multiple I2C BREAKOUTS with pull-up resistors doesn't work [UPDATE]

[UPDATE] Now it works fine but the as soon as I add the GY-521 module (hardware not software), it starts sending me crapy info Project uses: Arduino Pro Mini as brain FTDI as a programmer GY-521 ...
3
votes
1answer
89 views

Self made microphone burns Arduino

I'm very new to electrical engineering and I'm trying to read microphone input with Arduino Nano. I've made a separate microphone module (based on this example) and plugged it into Arduino like this: ...
0
votes
3answers
167 views

Why have resistor at end of circuit cycle if GND dissipates final energy?

The first challenge on the Arduino Uno manual is to make a closed circuit with a button and LED. The voltage is provided by the 5V pin (non IO), connected by wire to (+) on the bus (breadboard). The ...
1
vote
1answer
124 views

digitalPin giving lower voltage than Vcc

I am using an ATTINY88 for a project that requires to turn on an LED. Right now I am using pin PA1(ADC7/PCINT25). I noted, however, that when the pin is ON, I get about half the voltage that is ...
0
votes
1answer
35 views

How to encode resistance change (reed) for Arduino?

I have a water counter which switches reed on each 10 liters of water. I would like to count these values with Arduino. I wrote a program which counts changes from analog input and connected counter ...
1
vote
2answers
373 views

Use LDR with 220 ohm resistor

I have read many tutorials on LDR(Light dependent resistor) with Arduino which includes a 10 kilo ohm resistor but can i use it with 220 ohm resistor or even without resistor.
0
votes
3answers
94 views

How can I understand the circuit diagram for Arduino Starter Kit Project 4?

I have acquired the arduino starter kit project book, and the explanations seem at times confusing and difficult to understand. Concerning the above circuit diagram, the book states (I am ...
0
votes
1answer
40 views

How to 'label' module using electric techniques

I am in a project where it makes set of 'modules(set of separate circuits that will work as a sensor when connected to the board' that would be connected to Arduino Mega. Currently, I'm planning to ...
-1
votes
1answer
123 views

Photoresistor Switch

How would I use a photoresistor like a switch. My issue is it is always bleeding out a little bit of power and always on. Is there a way to connect it to a digital pin and when a resistance of xxx is ...
3
votes
3answers
1k views

What is the minimum wattage of resistors for breadboarding with Arduino Uno?

I'd like to buy new resistors for breadboarding with my Arduino Uno. There are 0.25W, 0.4W, 0.6W, 1W, 2W, 3W, 5W, 10W resistors in the shop. What is the most suitable for this operation?
0
votes
1answer
113 views

Diode lights generate false interruptions

I have spent quite a considerable time debugging my code that was triggering false interruptions. I have found out that the source of the error were the diode lights (on the picture). I would like to ...
0
votes
1answer
388 views

Driving multiple LED arrays with shift registers

The project I'm building requires multiple LED arrays. I'm going to wire these LEDs in parallel and then connect the arrays to individual pins on a shift register. In addition to the LEDs running in ...
1
vote
3answers
650 views

does INPUT_PULLUP uses power?

When using a digital pin as input, one has the option of using the internal arduino resistor, which is connected to VCC; that is setting the digital pin as INPUT_PULLUP, and then the pin reads HIGH. ...
1
vote
2answers
4k views

10k ohm Potentiometer vs 10k ohm Resistor on LCD Display

I'm trying to use a LCD Display with my Arduino, but I don't have a potentiometer and all of the guides I find always require one, usually a 10k ohm potentiometer. The point is that I'm not very good ...
2
votes
1answer
277 views

what is the importance of the resistors that connect to push buttons ? can i replace them by wires?

Please, iam a junior in arduino and i want to know what is the importance of the resistors that connect to push buttons? can i replace them by wires? thanks in advance.
0
votes
2answers
5k views

Can I supply the board's 3.3V directly to the AREF pin?

Short dumb question: can I connect the 3.3V pin and the analog reference pin (AREF) directly? I've heard mentions of a 32K internal resistor but I'm not willing to risk a short circuit without ...