Water Agitator Pump Needed

Hello there,

I would like to make a "sous vide" cooking device with a crock pot I have. More or less, the concept is to keep food cooking for long periods of time at a specific temperature, which will be regulated by a waterproof thermistor and an Atmega 2560. I have some experience setting such projects up and coding. However, I would like some sort of water agitator...I thought of using a small external air pump, with a tube to the bottom of the crock pot, to constantly blow a small stream of air into crock pot.

First of all, I had trouble finding a small enough air pump. I have settled on this one:

http://www.trossenrobotics.com/robotgeek-pump-small

However, it operates at 6 or 12V, neither of which can be supplied by the 2560.

Should I choose a different pump? Are them some amplifier configurations that will allow me to run this pump off of the 2560? Should I use a completely different method altogether to agitate the water?

Thank you in advance,

Arthur

Since the motor (pump) only needs to run in one direction (no forward and reverse) the driver for the pump can be a logic level MOSFET. To choose a proper MOSFET you will need to know the stall current of the pump motor.

For more information google “arduino mosfet motor driver”.
dc motor driver.jpg

student_cougar:
Should I choose a different pump? Are them some amplifier configurations that will allow me to run this pump off of the 2560? Should I use a completely different method altogether to agitate the water?

Even if you would get a 5V water pump (they do exist - I have a bag full of them) you can't power it off the Arduino board as its regulator just can't take the strain. You have to use a separate power supply for it - the power supply can be shared between the two but power to the pump must be split off before the Arduino board.

Thank you both! I will look into a transistor combination that would allow me to use the pump, and perhaps a separate power supply.