Questions tagged [arduino]
Be sure to use the Arduino Stack Exchange for questions that are more Arduino and less electronics.
6,642
questions
0
votes
2answers
23 views
What are these female 2.54mm (0.1") crimp terminals?
So I but some crimping terminals to make my own custom cable connections for the first time today for an Arduino project I'm currently working on.
Comparing to some older ones I have from premade ...
0
votes
4answers
59 views
Electromagnetic 7-segment flip display: H-Bridge alternatives?
I have an electromagnetic 7-segment flip display which has 28 electromagnets for 4 digits.
They run on 20V, have a 7.5W power rating and need alternate polarity applied to switch between the 'on' and ...
0
votes
1answer
58 views
How to increase Amperage while keeping the Voltage the same
I currently have an Arduino Uno board which has an output of around 5V @ 900mA.
is it possible to bump up the Amperage to around 3-4A while keeping the Voltage the same? Maybe with a Transistor, but i ...
0
votes
0answers
28 views
Controller Motor With Multiple Transistors with Arduino
I am trying to control a motor with two MOSEFT transistors (one is enabled and the other is disabled).
The problem is Ardunio requires the grounds to be connected which causes the voltage where M1 ...
1
vote
1answer
17 views
How to connect a Sparkfun LiPoly Charger to an Arduino Nano?
I was able to upload the Adafruit SSD 1306 OLED Library to an OLED Display using an Arduino Nano.
Now I want to power the Arduino Nano via a Lipo Battery but the battery must be rechargeable and I ...
1
vote
0answers
33 views
OBD2 Gateway Over IP
Goal of my project is to transmit and reconstruct data from OBD2 port, creating a "wireless gateway" between car and diagnostics tool.
OBD2 is On Board Diagnostics port required on every car, it uses ...
0
votes
0answers
23 views
Control motor direction with BTS7960
I am using the same BTS but I am controlling it with labview. I am able to control the speed in one direction, even though I have both R PWM and L PWM connected to PWM pins 3 and 7 respectively on my ...
0
votes
0answers
46 views
Why does my circuit short when powering through the same board as compared to an external power?
I have designed a board which follows this schematic:
What I’m trying to achieve is using a N-Channel MOSFET to make the SDOOR inputs connected. The SDOOR inputs are from another controller (STM20) ...
0
votes
0answers
27 views
Good switching regulator for esp32? [closed]
Hi Im planning to design pcb with esp32 chip. Problem Ive run into is power supply. Ill be using esp32 in my car which battery tipically is 13v-14. Linear regulators is to hot to drop that voltage. In ...
0
votes
1answer
31 views
Potentiometer volume control for a piezo buzzer in bridge (2-pin) configuration
I have a 10K potentiometer that I'd like to use to control the volume of a piezo transducer/buzzer, which is driven by one or more MCU PWM-capable pins (ranging from 0 to 3.3V). Originally, my ...
0
votes
0answers
28 views
NODEMCU _ MCP23017 IO Port Expander Schematic Design
I am designing a relay driver using NodeMCU and need additional IO Ports, therefore i have designed a schematic utilizing MCP23017.
I think the schematic looks good, however before i order PCB's ...
1
vote
3answers
107 views
Connect a Switchboard to Arduino
Sorry if this is a simple question, but I‘m quite new to Arduino. What I‘m looking for is a way to connect 100+ strain gauges to one Arduino board.
Now, those each need a separate ADC (HX711) to ...
0
votes
1answer
54 views
What Is The Correct Way To Recombine A Split Serial Signal?
I am trying to replace the lamp and ballast assembly in an Acer P1500 DLP projector. The ballast is an OSRAM PT-VIP-05 COMPACT. It features a UART control scheme that allows the motherboard to query ...
0
votes
2answers
49 views
Wrong ground reference producing wrong output on ADS1115
I am currently working on a project, which involves measuring current in a DC circuit and storing that generated data on an arduino microcontroller.
I decided to go with the ADS1115 and a shunt, which ...
0
votes
2answers
49 views
Arduino for detecting low voltage on UPS
Scraping together some parts, I managed to build a 22AH 12V battery pack, but I don't want to damage the batteries.
I am using 4x 12V 5.5AH UPS batteries wired in parallel.
I have an Arduino Uno, ...
1
vote
1answer
33 views
UART noise on audio lines
I have a fairly simple circuit with an Arduino and a SA818 RF module, I'm providing 3v3 power to the SA818 via two series diodes (dirty I know) and am communicating using software serial, of which the ...
0
votes
1answer
37 views
High Power LED Circuit Design & Constant Current Source Question/Feedback
I'm trying to design a dimmable LED circuit board. It's controlled by Arduino with its PWM signals. I'm new to electronics so I have some question regarding my design and knowledge on it. I've ...
0
votes
1answer
35 views
How do I read a simple touch sensor value from Arduino? [closed]
I suppose instead of connecting to the LED it will connect to A3 on the Arduino for example but I'm having a hard time making it work.
I don't know which point on the circuit should be connected to ...
0
votes
1answer
38 views
A simple Arduino Uno HC-05 system doesn't work
I have an Arduino Uno, HC-05 module and an LED.
I want to connect the HC-05 to my phone and with an app be able to turn on and off the LED and at the same time sending a message from the Arduino to ...
0
votes
0answers
26 views
What is the recommended way to connect TP4056 charger module to NodeMCU v2
I want to power a NodeMCU v2 with a 3.7v 2000 mAh LiPo battery and charge the battery with the NodeMCU connected (i.e. under load). After looking into various forums, I ordered a TP4056 battery ...
1
vote
0answers
18 views
ESP8266-12E & BPM180 - Bad pressure retrieved
I have NodeMCU (esp8266-12E module) and connected BMP-180.
I try to read pressure from BMP-180 in async web request, but it reads bad value.
For testing purposes I log pressure in loop() - and it's ...
0
votes
0answers
41 views
Using one electrical pump for multiple hoses [migrated]
I'm currently trying to figure out a cheap way to build a cocktail machine.
For now the machine should have about 20-30 possible input liquids. These liquids should remain in their original bottle ...
0
votes
1answer
41 views
Circuit design and power management in an Arduino project with stepper motors and solonoids
I am working on a design for a Arduino driven project that controls a 1.7A stepper motor and 2 small solenoid valves. I am using a 12v power supply (Meanwell MDR-60-12) to power the stepper motor (...
0
votes
0answers
85 views
How should I connect 5 buttons to arduino so that I can use the least number of inputs all the buttons are connected to ground [migrated]
The problem here is that I want to connect 5 input buttons to an Arduino but I do not want to utilize 5 input pins of Arduino, is there any matrix like connection using which I can reduce the number ...
0
votes
1answer
67 views
Arduino current measurement
Hello I am planning to use an Arduino to make a joulemeter for a current range of 0-30 amps and voltage range of 0-24V. The voltage measurement is fine but I have questions about current measurement.
...
-1
votes
1answer
123 views
2n2222 can not make it work as gate
simulate this circuit – Schematic created using CircuitLab
I am trying to make a simple switch with the 2N2222, so i can send 5 volts from a 3.3 V output pin on an arduino/raspberry pi.
I have ...
0
votes
0answers
37 views
NodeMCU-12E - Conflict between I2C and SPI
I have SPI SD-card module connected to nodeMCU, and it's worked well. Next I try to connect I2C sensor, and it doesn't work. Looks like SPI conflicts with I2C, because when I disconnect SD-card, I2C ...
2
votes
2answers
405 views
Purpose of a Pull-Down resistor [duplicate]
Being just a beginner I'm really getting confused of pull-down resistors.
Please have a look at the diagram below. Here there is a 10k pull down resistor is connected to ground and the pin 2 of ...
0
votes
1answer
39 views
ESC signal standard and PWM frequency
I got the following code from the video. However, I encountered an issue that, the motor tended to stop working at maximum value.
...
1
vote
4answers
111 views
74HC595 8x16led matrix arduino
I'm currently trying to learn how multi shifting is working and have therefore started a project where I wanna drive 2X 8x8 LED matrix with an Arduino. I have found it that I should work with the ...
3
votes
0answers
74 views
Replacing an ammeter with voltmeter?
I have found this circuit of a millivoltmeter, and it seems like something which as a hobbyist I can do it, and the range of the measurement is very suiting one of my projects, but I would like to ...
8
votes
5answers
262 views
Infinite loop on microcontroller vs modern CPU
On a microcontroller (more specifically, on an Arduino Uno board using the ATmega 328P microcontroller) I would normally use an infinite loop to check for inputs etc (in Arduino land, this is normally ...
8
votes
4answers
3k views
How can I make my PNP amplifier circuit to turn off faster?
I'm using the following circuit to switch a 24V signal to a PLC. The rising edge is fast and perfect(38 ns) but the falling edge of the signal is not as good(3.5us)!
How can I modify this circuit to ...
-1
votes
0answers
40 views
What is the acceptable voltage range for 3.3v sensors and other devices?
I have a few sensors I am working with that accept 3.3 voltage only. I am also working with a few Arduino Nano-type boards, which are not of perfect quality and give out 3.5-3.6v at the 3.3v pin. Now, ...
1
vote
1answer
92 views
AC Nanovoltmeter for Arduino alike?
I have searched across web, but I am unable to find such a circuit.
I am looking for a circuit of a AC nano-voltmeter in range 5-10 to 100 nV which output is suitable to be handled by some precise ...
0
votes
1answer
52 views
Proper usage of PC817 Optocoupler
I'm creating a logic based circuit and below is my schematic.
The circuit first steps down a 24 VDC input to about 3.7 VDC using a 150K ohm resistance and a 5.1V Zener diode.
This 3.7 VDC is fed to ...
1
vote
5answers
98 views
Small 5V BLDC motor controller - 6 mosfet IC
I am creating follow focus system (motor with gears that moves camera lens ring). I think the best choice is BLDC motor (DC geared are too loud, stepper don't have enough torque or too big).
I need ...
0
votes
0answers
56 views
0-5V Audio Signal with TL082
I am working on an Arduino project that requires me to be able to handle audio input from a 1/4" input jack, and it needs to be powered with just one 9V DC input. Since the Arduino cannot process ...
0
votes
0answers
17 views
Arduino FFT noobie question [migrated]
How do you obtain the real and imaginary parts of a signal using FFT in arduino?
I could not find a particular tutorial with code for this purpose in the internet.
0
votes
1answer
33 views
Non-intrusive Detection of Power On/Off for a Piece of Instrument
I have a spectrometer that is basically a diffraction grating driven by a stepper motor. I am controlling it with an Arduino UNO that sends off a pulse train, each pulse moves the grating by some ...
2
votes
1answer
80 views
Trying to wire up a couple dozen LED-lit toggle switches to an Arduino Mega
Update: Worked out a rough (I'm sure) schematic of the current idea for a smaller version of the circuit. A bit of info before the question;
The Arduino has a current cap of 200ma across all I/O pins,...
0
votes
2answers
35 views
3v output to switch on transistor for 5v fan
Im having trouble selecting resistors for my circuit. I have a 5v supply and my wemos board has a digital pin output of 3v.
I want to use the wemos output pin to switch a transistor (BC547) on to ...
0
votes
2answers
95 views
How can I use an Arduino to simulate button presses on this Remote Control PCB
I read with interest here this post: How can I use an Arduino to simulate button presses on this PCB
I am a beginner in this and I am trying to learn how to do this based on a small remote control I ...
1
vote
1answer
64 views
Voltage and Current Sensor for Alternating Current
I want to measure the voltage and current of a AC powered device using a micro controller like Arduino. I am unable to find it.(I am new to these).
Is there a circuit or sensor which isolates from the ...
0
votes
1answer
46 views
Soldering iron thermocouple measurement HELP
I'm working on a relatively simple soldering iron circuit. I'm using a T12 tip, which consists of a resistor and thermocouple in series.
I'm driving the gate of the N channel mosfet with 20V via a ...
16
votes
6answers
11k views
In this transistor circuit, what is the purpose of the diode across the motor?
I am trying to follow an Audrino tutorial with my kid and I am confused by the role of the diode in this circuit.
In particular, I have the following questions:
It looks like the circuit will work ...
-1
votes
0answers
42 views
HC-05 missing characters received via serial - possible issue with voltage divider
I have a HC-05 set up (like here) with the receive pin (of the hc-05) getting a voltage of 3.3V from a resistor network of 1.2k and 2.2k from the Arduinos 5V. (I also have a simple software serial ...
-1
votes
1answer
50 views
How to control a boost converter by using pwm from Arduino [closed]
I am creating a simple boost converter that step up voltage in the range 5V-30V. The switch is a MOSFET controlled by PWM output of an Arduino (with additional necessary components.) I want to ...
0
votes
1answer
31 views
How to use arduino control an ESC and flash?
Basically, I want to use PWM wave or something alike from Arduino to directly control the speed of a brushless motor through an ESC.
I saw an example on the Arduino Brushless Motor Control Tutorial | ...
0
votes
0answers
30 views
Wireless Audio Transmission with NRF24L01
:)
I have been planning to do a project on transmitting audio through arduino using NRF24L01 RF Modules at the same time sending data commands. I am really a beginner in terms of audio circuits so I ...
