Tagged Questions
0
votes
1answer
34 views
Powering circuit and Arduino with single power source
I am trying to power an Arduino Uno as well as my circuit using Li-Ion batteries. They are 2 18650 Lithium Ion batteries (rated at 3.4 V each = 7.4 V total).
I have this battery plugged into the Vin ...
1
vote
0answers
71 views
Designing circuit with Arduino and optocoupler: beginners problem
Firstly, I am a beginning hobbyist starting doing some electronics and this is my absolutely first attempt in trying to automate something. Here is my circuit (or what I intend):
I don't know if my ...
0
votes
4answers
133 views
Voltage decreases on higher current
I have a circuit composed of Arduino Mini Pro 3.3V and GY-GPS6MV2 (GPS Ublox NEO-6M). I have tried to power it with 3 different sources:
3xAA NiMH in serie connected to RAW pin of Arduino and using ...
0
votes
1answer
95 views
how to provide a steady voltage, in case of source voltage drop due to heavy consumers in the circuit
I am designing an arduino circuit in which the power source is a battery connected to some heavy current consumers, these consumers are intended to work for short time and infrequently, my question is ...
4
votes
3answers
280 views
Thermistor control of peltier voltage with Arduino (for DSLR chill box project)
I am mildly familiar with electronics, mostly from playing around with electronics kits as a kid. That was a long time ago, though, maybe as much as 20 years ago. I am currently working on a cold or ...
0
votes
1answer
70 views
Female Rectangular Headers with Long Pins (Pass-through style)
Female Rectangular Headers with long pins (passthrough style) are used to stack/connect an Arduino shield board to the Arduino board. 1x8 and 1x6 position headers are easily found.
Problem: However ...
2
votes
4answers
184 views
Thermocouple reading different from Commercial Datalogger when using Arduino
A K-type thermocouple is connected to a thermocouple breakout board that outputs 1.2V to 8.8V that covers the entire -260C - 1380 °C of K-type thermocouple. This output is than divided by ...
0
votes
1answer
83 views
Differential analog signal conversion using Arduino Uno
I need to perform a A/D conversion for a differential signal using Arduino Uno. I have tried a software method where I connect one input to A0 and another to A1, read ADC for both channels and then ...
0
votes
1answer
49 views
Arduino Mega driving 5V to 12 V
I am working on a project which involves using an Arduino Mega, and I am trying to use an NMOSFET (BUZ101S) and an NPN BJT (2N3904) to drive the 5V output from the MCU back and forth between 0V and ...
0
votes
2answers
73 views
Transistor Arduino Loss of Voltage
simulate this circuit – Schematic created using CircuitLab
I have a wire connected to the base of the transistor that goes to the PWM pin 9 on the Arduino Uno.
On the collector of the ...
1
vote
2answers
265 views
Do I have other options but shorting out those diodes?
I've been trying to connect my LED stripe -> rgb amplifier -> Arduino Mega 2560 -> PC. After connecting it according to this guide, nothing happened.
Looking inside the amplifier I noticed the three ...
1
vote
1answer
397 views
Calculating battery percentage using an Arduino
I'm doing a little project using a Lipoly charger and a 2500mAh 3.7V battery, both from Adafruit. I'm trying to display the percentage left on the battery. For that I'm using this little sketch :
...
0
votes
4answers
189 views
3.3V Regulator giving 4.8V with 5V Input
The ST L78L33ACZ 3.3V voltage regulator has 5.028V in the Vin pin but the Vout pin is giving 4.765V.
The datasheet states that ...
1
vote
1answer
113 views
Do I need trivial resistor or not if V/I = zero or almost zero
As the title says, do I need trivial resistor or not if V/I = zero or almost zero?
For instance:
Assume I'm using 3V buzzer and 2V LED in series with an Arduino 5V pin.
$$R = \frac{(3 + 2 - ...
0
votes
1answer
116 views
Drive a DC motor rated for higher than 5V
How would I go about if wanted to drive a 10V DC motor with 5V logic, suuch as the one found by an Arduino, at different rotation speeds? Is there such thing as a motor driver that accepts an ...
1
vote
3answers
482 views
Read Positive and Negative Voltage in Arduino
It's a long story, but I took apart and RC car and wanted to have the Arduino use analogRead() to get the values of my motors and steering. I have measured with my ...
2
votes
2answers
481 views
How to power a Arduino Yun with a 6V battery?
I would like to power my Arduino Yun board with the following battery:
Arduino Yun has a VIN pin that represents the input voltage to the Arduino board. The official documentation says:
Unlike ...
1
vote
1answer
356 views
Designing/looking for a circuit board for a vaporizer [closed]
I recently decided to look for/create a board for a vaporizer and have no idea where to start. I will probably end up programming the program in C or C++. To better explain this, I will explain the ...
0
votes
1answer
213 views
How can I limit the current in a 12v car battery to be safe for my 25a motor driver?
I have a 25amp Sabertooth Motor controller that can be powered by my 12v car battery. I have big 24v wheelchair motors attached to the motor controller.
I do not know how much current that the motors ...
-3
votes
2answers
488 views
Max voltage for Arduino ATmega328 VCC pin (not raw!)
I am thinking about getting both the Pro Mini 3.3V and the 5V boards.
Example (but I may end up going generic, not sure yet)
3.3v: https://www.sparkfun.com/products/11114
5v: ...
0
votes
3answers
195 views
Regulated +5V drops when relays are switched on
A regulated power supply RAC02-055C/277 provides 5V to an Arduino driving 2 relays. The power supply is rated to provide 2W of power.
Connecting a multimeter between one of the leads of the power ...
0
votes
3answers
140 views
Voltage of Voltage Regulator changes when a Potential Divider is added
A Keithley 2400 Source meter is used to provide +7V. Using Fluke 179 Multimeter, the potential across the source meter leads is 7.00V.
The source meter is then ...
2
votes
1answer
168 views
Amplifying and Reading a 0-1 V signal into Arduino
I'm trying to read the (0~1V) output of a current transformer (CT) into the 10-bit ADC input of an Arduino Nano. The CT is sensing the L wire carrying 120V at 60Hz.
...
0
votes
1answer
75 views
7V or 12V Power Supplies for Arduino
The recommended input voltage for Arduino is 7-12V. Given that both 7V and 12V power supplies (AC-to-DC converters) are available, which voltage will be more suitable/practical? Could be in terms of ...
0
votes
4answers
279 views
Converting ~5V DC to 12V DC safely
We have an Arduino device that is using a sensor requiring ~12V. Are Step up devices safe? Are there any dangers in terms of current etc?
To elaborate; we plan to run the 5v supply from the arduino ...
-1
votes
1answer
261 views
1-Wire Network, Voltage and Current Questions
EDIT: Schematic updated to show multimeter test point as requested. Altered test points for first 3 questions.
EDIT: Added scope picture for Q4/5.
I have created the following test circuit to ...
2
votes
3answers
328 views
PWM'ed DC motor not running when loaded
I am trying to build a robot with the Arduino Uno and the H-Bridge SN75441.
The robot has 2 1.5V rated motors. I set it up with this tuto: http://www.mlbelanger.com/arduino/ard-bot/
So the circuit ...
0
votes
1answer
220 views
Power arduino with 7.2v rc racing battery?
Sorry if this is a bit of a stupid question, I just want to make sure before I destroy my arduino.. Is it okay if I power my Arduino Mega from a high current 7.2v battery pack?
The battery I'm ...
1
vote
2answers
859 views
Switching 9V using a NPN transistor and an Arduino
First of all, I'd like to say I'm not an Electrical engineer so please bear with me. I haven't got a sketch for what I'm trying to achieve but hopefully I can explain it ok.
I have an NPN transistor ...
1
vote
4answers
218 views
Relevance of amperage in a voltage divider circuit
I'm not very competent on the electrical engineering, so forgive me if this is a dumb question.
I'm trying to make a voltage divider circuit to monitor the battery level of a project I'm working on. ...
0
votes
1answer
152 views
How do I increase the voltage of a circuit that powers and transmits data to an led
I am a noob, but I managed to make a TV-B-Gone out of an Arduino UNO and some parts (I used this tutorial: http://www.instructables.com/id/Arduino-TV-B-Gone/). It only does one led, but I want it to ...
1
vote
2answers
2k views
Wiring an IR phototransistor
I'm a beginner at electronics. I'm trying to use this Infrared phototransistor and my Arduino together: http://www.maplin.co.uk/infrared-transmitter-and-receiver-10379
I'm using the popular library ...
0
votes
3answers
124 views
LEDs through Arduino Uno [duplicate]
I know next to nothing about electric engineering, so I got the Arduino Uno R3 and a bunch of LEDs to play around with and hopefully learn something. I have no idea about the proper terminology or ...
-1
votes
2answers
610 views
How to use a digital potentiometer to control current
I am attempting to rig an RC Car's rear wheels to an arduino.
Initially I attempted to just hook it into the powered digital pins but after MUCH headache I realized I wasn't getting enough current.
...
0
votes
1answer
122 views
Multiple LED over Serial communication with Arduino
Several LEDs are being driven by Arduino. The LEDs to be lit up are sent to Arduino over serial port. When Arduino receives 12H\n over serial, it will execute ...
4
votes
2answers
1k views
Trouble on switching a 3V relay with Arduino digital pins
I am using the Arduino Ethernet with POE and I am in trouble when I have to enable my relay by using a digital pin. What I would like to make is to start a motor by using a relay, which relay is ...
1
vote
1answer
56 views
Reading power consumption data
So if I have a batter that says it can produce a max of 2000mAh and a device that says it uses 3.6 mA does that mean I can run the device for 2000mAh / 3.6mA ?
How does the voltage get factored into ...
2
votes
4answers
287 views
How can I electronically sense the state of an LED in another device with an Arduino?
I'm working on a project to integrate an off the shelf garage door monitor with an Arduino. The base station has a pair of LED's that flash in different patterns to indicate the state of the remote ...
0
votes
0answers
96 views
Step Voltage Down
I have an Arduino and several Strings of LEDs being powered by a wall wort. The LED portion is fine as is, however the Arduino has an ethernet shield attached and it is getting very hot when on. The ...
5
votes
2answers
1k views
Vin output voltage of an Arduino
I have got a very simple and fast question.
I have connected 6v to the power jack of my arduino, and when I tested the output voltage from the Vin, it turns to be 5.3v with no connection and 4.8 with ...
1
vote
1answer
498 views
Verify changed analog reference voltage on Arduino
I want a reference analog voltage of 2.0 volts on a 3.3 V Arduino.
Since there is an internal resistance of 32k on the Arduino, I hooked up a 21k resistor to Vcc.
How can I confirm that I now have ...
1
vote
1answer
539 views
What could happen if I plug into my Arduino an AC adapter instead of a DC one?
I´ve read that Arduino needs a DC adapter and not an AC one, I know that.
What could happen if I plug into my arduino an AC adapter?
I need to do a quick test with two small 4.5v DC motors, and I ...
3
votes
1answer
231 views
Why does an arduino need 7V if it uses 5V?
The recommended voltage for an arduino Vin is 7-12V. The Vin can't be outside 6-20V for proper operation. If Arduino uses 5V on its rails and for its logic, why is 7V needed?
2
votes
1answer
185 views
How do I convert a signal of 3v to 2v to a signal of 0 to 5 v
I'm measuring input voltages between 2v and 3v (3v volts corresponds to a reading of 0 and 2v corresponds to a reading of 10,000) on the analogue in of my arduino. I would like to measure the voltage ...
-2
votes
1answer
90 views
Arduino+MotorShield v3: Jumper's position (PWR Ext/Sel Ard) using DC motors [closed]
Is it necessarily to connect an additional external power supply to the "Motor Shield" when using DC motors?
Or enough to set the jumper on "Motor Shield" in "Sel Ard" position and connect the Arduino ...
1
vote
1answer
112 views
Reading signals in a car 9-14.5v and translating to arduino HIGH / LOW
I have a project that requires me to trigger certain events in an Arduino based on certain electronic devices in the car being switched on and off. I essentially need to read a 12v HIGH state in the ...
4
votes
3answers
1k views
Have I fried my Arduino UNO?
So I've recently been playing with my first Arduino, until it, for some weird reason, stopped working.
What I did:
I had it attached to a breadboard. When I say attached, I mean it was supplying ...
0
votes
1answer
214 views
How does a multimeter convert voltage/current to a numerical value?
Just wondering... How does a digital multimeter work ? How can it convert a voltage, a current or a resistance to a numerical value ? I guess there is some programmable chip inside, but how does this ...
2
votes
3answers
661 views
Circuit that can convert current pulses to voltage
I have an anemometer which outputs current pulses. I can't take it apart but I know there is a phototransistor and LED in parallel shining through holes to it. I was told that with 30m/s wind there ...
3
votes
2answers
423 views
Driving 3.3 V LEDs with an Arduino and a shift register
I'm planning to build a simple LED matrix with an Arduino and some 74HC595 shift registers. However my Ardiuno outputs 5 V to the registers which will pass that 5 V on. How and where along the line do ...
