Voltage question

Hi I am a beginner at electronics and I'm trying to build a "smart" electric toy car. Right now I am using 2 components : 1 Sensor and one motor controller. Both of them need 5V input to function(motor controller can handle more). I am currently using the standard 4-AA batteries to power the motor controller and I connected the sensor to the 5V Arduino.

My plan is to add more sensors but I don't want to have a different power source for each.

So my question is : Is there a way for them to both use the 5V arduino output and function as the same time without adding other components(except wires and soldering)?

If not, what do I need to add?



If the motor controller is controlling another power source to actually power the motors, then it can be "powered" by the Arduino. The sensor is no problem. The limit on what you can power from the Arduino is 40mA or less (preferably less) from each pin, with a total of 200mA from all pins.

Actually I would like to NOT have another power source. I'm aiming to have the lowest total weight possible, and those 4 AA batteries add quite some weight. I'd like to power both the sensor and the motor(very small toy car motor) trough the Arduino 5V power output.

it's only to have a single power source, to make it smaller and lighter.

If it's not possible I will keep the external power source. I'm new to electronics and I figured that if they both need 5V input I could use the arduino to power everything.

my mistake. I forgot to mention that the arduino itself was powered by a single 9V battery which was the simplest way I found to power it up. I wanted to use the power from that battery without having to modify the wiring from the battery to the arduino.

From what you tell I understand that the way to go would be to power both the arduino and the motor from the battery (trough parallel or serial wiring) rather than powering only the arduino and using to power the motor. Does this sound right?

single 9V battery

You are aware that a 9V Battery is BIG on volts but LOW on power. You won't run much for very long.

Compare: Double AA Battery is designed for: 50MA loads 9V Battery designed for 15MA loads.

Does the sensor need 5V? If not, power the arduino & sensor in parallel with 4.5V from 3 of the batteries direct to the VCC pin, and use all 4 batteries for the motors.

Thanks all for the replies I think I jumped into that too fast, I'm gonna go do some more reading before going further on that.

Compare: Double AA Battery is designed for: 50MA loads 9V Battery designed for 15MA loads.

He did, of course, mean “Compare: Double AA Battery is designed for: 50mA loads 9V Battery designed for 15mA loads.” :wink: