so i was just doing the project when i have the bright i idea to put 16 volts through the ext power block but the arduino smoked and stopped working any reasons
Thanks for letting us know.
a7
So i wanted to know any possible reasons for it
If you show a schematic of how you have all this stuff connected and show us where your connected 16 volts, then someone can suggest the problem.
You most likely connected the 16V to your Arduino somehow. That will make its smoke.
Smoking is a health hazard?
There are several boards that fall under the umbrella name of Arduino Uno. None of them, to my knowledge, have anything called an "ext power block".
If you are referring to the barrel plug connector, and if you are referring to an Arduino Uno R3, by applying 16V to that connector, you have exceeded the allowable voltage for that input.
As stated in many, many places, beginning with the official Arduino Uno R3 documentation, the allowable voltage input for the barrel plug connector is 7-12 volts.
Or are you referring to some connector on your completely unspecified motor driver? Your punctuation free lower case word soup makes it very difficult to tell exactly what it is you are actually referring to.
Noooo im using a motor driver
Oh, you are using a motor driver. Was it something on the driver that smoked, or something on the Arduino itself? And could you please be so good as to provide a link to said driver so that we might know which motor driver out of the dozens available for the Arduino that you are in fact using?
The Arduino smoked or the Voltage Regulator smoked? The Arduino UNO Rev 3 board has two onboard regulators, one for making 3.3 volts and one for making 5.0 volts. Both are linear voltage regulators. While this seems to apply:
The Arduino Uno has a 5-volt linear voltage regulator on its circuit board, allowing you to use its coaxial power connector to connect a power supply of 8 to 20 volts DC. The regulator reduces this to the 5 volt DC level that the Arduino uses.
That 8 to 20 volts is not quite true. When I apply 12 volts the 5.0 volt regulator starts getting hot to the touch. You need to understand how a linear regulator actually works. If I start with 16 volts in and I get 5 volts out did you ever wonder where the 16 - 5 = 11 volts went? Combine the 11 volts with the current being passed through the regulator and start thinking watts and heat produced. Normally the regulator will go into thermal overload and shut down but not always.
So what component exactly smoked?
Ron
Im quite sure its not the motor driver as the led and everythings working but the arduino is not i think it was the regulator bit isnt it not supposed to give voltage to the arduino?
I am using a motor driver sheild
Please post a link to your motor driver.
Please post a schematic of your project, with attention to where power comes from and how it is routed to the parts that need power.
So far it sounds awfully like you've damaged your Arduino board.
Please post pictures of the motor driver, too and bottom, and your toasted Arduino board, top and bottom.
A repair is perhaps beyond your abilities, and perhaps beyond being a reasonable course of action for anyone.
Try uploading the simple blink sketch to the Arduino board with nothing else attached, just the board and the USB cable to your computer.
a7
Well the picture looks like this:
Looks to me like the 5.0 Volt regulator on an Arduino Uno Rev 3 or Mega board powers the Arduino as well as anything and everything 5.0 volts including anything connected to the boards 5.0 volts. The connector on the left in the image is the barrel connector.
Ron
Instead of the 9v i used 4 li ions in parallel for 16 volts i cant gives pictures as its with my friend but according to me the regulators toast what i want to know is can the motor driver transmits power to the arduino… sorry for the rookie questions
I assume you mean series rather than parallel on the batteries.
I would remove the shield and try powering via the USB port and run something simple like the blink example code.
Ron
We're 15 messages into the topic, and we're finally getting some useful information.
That's a clone of the long discontinued Adafruit V1 motor shield. People continue to buy it because it's cheap. And thereby learn the lesson of "the poor man pays twice".
Did you happen to have the PWR jumper on the motor shield in place when you applied 16V to the shield? Thereby delivering 16V to the input of the 5V regulator on the Arduino? Thereby overloading the regulator and causing it to burn up?
Who must we believe 
From Arduino Uno Rev3 — Arduino Online Shop
Yes, I know there is a difference between 'recommended' and 'limit' 
I'll believe the engineers rather than the marketing people every single time.
Besides... that's for an official R3. Care to place a wager on the OP having a 3rd party board with components with lower voltage ratings being used?
1 Like
Ok this might be a rookie question but what is a pwr jumper
And yes thats the v1 i bought it cuz it was relatively cheaper…..and why was it discontinued was there any problems with it
Well my freind did buy it of somewhere sketchy