My Arduino UNO set, rest continuallywhen l'm using external power supply

Hi, l’m working on obstacle avoiding robot project using arduino uno everything was fine but recently l got a problem which is that my arduino reset and set itself continuously when l’m using external power supply{ l made it manually}. when l’m using the usb everything works fine but the board set and reset continuously and my robot and the program doesnt work with external power supply ! this problem started with me 3 days ago (after l programmed the arduino using usb at the same time the external power supply was turned on and connected to the board). I’m using dual motor shield with max current of 2A from Adafruit. plez help me to identify the reasons beyond this problem =( =( =( =( =( =( =(


What voltage is your external supply? and what voltage is making to the Arduino when the robot is in motion. If you are using the electrical jack on hte Arduino it needs 7 to 9 volts for the regulator on the Arduino board to function properly.

l'm using 5v for the arduino board and 5v fro the motor shield

l just tried 9v for the ardiuno and 5v for the motor shield and vice verse but the problem is sill . plez help me guys and thanks in advance =( =( =( =( =( =( =( =( =(

Get something proper. Are you even sure this thing is DC ?

fahmi5555: l'm using 5v for the arduino board and 5v fro the motor shield

The External power supply for Arduino Unos needs to be 7-12V.

From this spec

Input Voltage (recommended) 7-12V

The board can operate on an external supply of 6 to 20 volts. If supplied with less than 7V, however, the 5V pin may supply less than five volts and the board may be unstable. If using more than 12V, the voltage regulator may overheat and damage the board. The recommended range is 7 to 12 volts.

Asking if there is a problem with part of your circuit and not supplying any details isn't a good way to get an answer.

Details necessary: 1. What is the voltage and current capability of your external power supply. 2. Where (pins) are you connecting that supply to?

First, you need to use 7 to 12 volts; check Second, have you check the quality of your power supply ? I strongly recommend Have you used AA batteries ?