Tagged Questions

4
votes
2answers
112 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
78 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
170 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 ...
2
votes
2answers
144 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 ...
0
votes
1answer
124 views

Getting a incorrect voltage from a analog sensor

I'm trying to build a very simple thermometer using shift registers, 7-segment LEDs, and a LM35. The idea of the project is to learn more about shift registers and how to use them. What I've done so ...
1
vote
0answers
398 views

ACS714 5A AC Current Sensing arduino

hey guys i just got my ACS714 -5 to +5A IC i am new the current and voltage sensing i googled for tutorials on ACS714 5A but couldn't find a suitable tutorial with AC sensing. I got the code below ...
1
vote
3answers
359 views

Common ground and voltages

Further to a question I asked earlier, I realised that common ground confuses me. I have a USB powered Arduino and a separate Battery supply. The battery supply negative is connected to the Arduino ...
2
votes
4answers
948 views

How can I drive 12v LEDs from my Arduino Nano?

Background I am building a scale RC helicopter and ordered a bunch of 3mm LEDs to give it some nice navigation and strobe lights which I plan to drive with an Arduino Nano. Problem is that I goofed ...
2
votes
1answer
790 views

Arduino & JY-MCU Bluetooth module

I've got a bluetooth module from dx and connected it to my Arduino UNO R3. It was working just perfect but after a couple of hours of work it just stopped sending data. I think, the problem is with ...
0
votes
1answer
194 views

How to tell if mains voltage is on with microcontroller?

I want to be able to tell if the mains voltage is on or off with an Arduino. How could I do this safely with minimal components (or components from Radio Shack)?
0
votes
0answers
35 views

Can I use a 12V / 2A power supply with a 12V / 1.3A motor? [duplicate]

Possible Duplicate: Choosing power supply, how to get the voltage and current ratings? I just ordered this motor, and the description says it was tested with a 12V / 1.3A power supply. Now ...
2
votes
2answers
89 views

Maximum effective range of RG-6/U in CCTV

How long RG-6u i can use in my cctv? what's is the effective range using RG-6u?
1
vote
1answer
159 views

Connecting arduino to power another device

I have an arduino board which I want to use to give power to a device which uses two 1.5V batteries. I think I have to remove the batteries from the device and control the power supply via arduino, ...
1
vote
0answers
488 views

Arduino Mega run on 2 AA batteries? [closed]

I am completely new to electronics and I have a question. I read that the Arduino Mega runs on 5V and that a supply of 6-12V is recommended for stable operation of the board. So what if I wanted to ...
0
votes
2answers
747 views

Using Vin pin on Arduino with a shield

I just bought a wifi module shield and using it with Arduino. I power Arduino (with the wifi shield on it) via USB from the PC. I need to demonstrate it without using the PC as a power supply. And I ...
1
vote
4answers
3k views

How can a Arduino (5v) power a device that operates on >12v?

Say I buy a device that requires 25 volts to function, but I want to control it using my 5v arduino. How would I go about powering/controlling higher voltage devices?
6
votes
1answer
671 views

With a uC, I can input analog voltage levels, how do I output them?

With a uC, I can input analog voltage levels, how do I output them? I have a simple Arduino Uno R3 I had picked up, which has a few of each pin types (analog input, digital output/pwm, serial) and ...
4
votes
3answers
613 views

How can I know if I'm safe from burning out my robot with more voltage?

I have a Wowwee animatronic robot that I've been tinkering with, with the goal of hooking my arduino up to it so that I can control it from my computer. The problem is, using a multimeter, I've ...
3
votes
1answer
188 views

Arduino LilyPad Input Voltages Below the Input Voltage in Specs

The LilyPad spec page says: Input Voltage 2.7-5.5 V I understand that an input voltage greater than 5.5 V would damage the device, but what if it's below 2.7 ...
0
votes
2answers
414 views

TLC5940 and ADXL335 circuit 'glitches' on perfboard. Need decoupling caps?

I created a circuit containing one TLC5940 and one ADXL335 breakout board. The ADXL board comes configured with 0.1 uF capacitors to set the bandwidth of each axis to 50Hz. It is wired to an Arduino ...
2
votes
2answers
4k views

Arduino, controlling leds with 3.3V even though dig. has 5V?

The LEDs I have can nicely run on 3.3V, with a minimal power dissipation to bring down 3.3V to 2.0V. My Arduino has 5V for its digital pins however, and I do not know of a way to use 3.3V unless I ...
4
votes
4answers
1k views

Why won't my arduino board read an analog pin correctly?

I'm working with an Arduino Uno board. I have a series of voltage dividing circuits off to the side of a breadboard to give me four different voltages. I'm connecting to my laptop. I am using the ...
1
vote
2answers
219 views

Connect a microcontroller to a gadget

Although I have average programming skills, I'm not far from being an noob concerning electronics! I therefore want to kindly ask you to help me connect my (already programmed) Arduino Uno to the ...
2
votes
3answers
463 views

Does this amplifier work with 5V?

I'm using an Arduino to read an analog signal from an electret microphone. Here is the circuit: But I will be powering it with 5V from the Arduino, So would this work okay? Thanks!
1
vote
1answer
498 views

Is there an Amp + Volt-meter on a chip or should I use the Arduino Analog?

I'm thinking of building a general purpose battery charger. It would charge LiPo packs, 9V, AA, AAA, etc... I've been doing a bit of Googling and read that the internal Phone charging circuits tend ...
4
votes
4answers
3k views

Negative voltage from Arduino?

I recently got a INA101HP see picture below. I was trying to use it on a breadboard. To power the op amp I connected 5V to +vcc pin but then I realized I did not really get how to provide -5V for the ...
2
votes
4answers
2k views

Voltage drops and current for LED?

I created the following circuit on a breadboard and used the Arduino Uno 3.3V supply for the power supply: ...
2
votes
2answers
2k views

Best way to get +5V or +12V or 0V from arduino pin

I am working on an eeprom programmer as an Arduino shield. There are two pins on my eeprom that require a 12V signal as part of the programming process. One of them is an address pin that I am also ...
3
votes
1answer
705 views

What is the voltage range on an Arduino pin when doing analogRead()?

I know what an Arduino's ADC generates a number with 10 bits of resolution (0 to 1023). How is this number generated? Is there a minimum and maximum voltage it will assign 0 and 1023 to, respectively? ...
3
votes
2answers
997 views

Circuit for testing LiPo batteries?

I have some lipo batteries I'd like to test. Ideally it would do the following: how much time does it take to discharge to minimum allowed voltage? how flat is the discharge curve? how many mAh ...
2
votes
2answers
2k views

Arduino Input/Output Range (Cable Length)

So I have this crazy idea to illuminate a few Christmas lights on the exterior of my house this weekend. I plan on running 2 Cat5e cables about 11.5 meters (~38 feet) from an Arduino board to sensors ...
5
votes
5answers
2k views

How do I read analog devices that produce relatively high voltage?

I found a sensor recently that emits ±90V (AC) on stimulus. How would I go about reading this from an arduino? Update I didn't think there were so many options. :) The kind of thing I'm looking ...
22
votes
4answers
3k views

\$I^2C\$ 3.3 to 5.0 V conversion

I'm trying to interface a 3.3V \$I^2C\$ device to a 5V Arduino. I don't have any problem with SCL line. I can use a simple voltage divider but I have an issue with the SDA line as this is ...
7
votes
5answers
2k views

Implementing I2C to analog

How can I implement (or maybe there is an IC that already does that) a board whose input would be I2C and output would be analog voltage (0V - 5V) ? Eventually I would like to connect a couple of ...
4
votes
3answers
723 views

Correct DC Adapter type to use for Arduino

What's the correct DC Adapter to use with Arduino? Voltage etc?