Thread: lightweight, inexpensive speed controllers
View Single Post
  #16   Spotlight this post!  
Unread 04-12-2013, 06:52
efoote868 efoote868 is offline
foote stepped in
AKA: E. Foote
FRC #0868
Team Role: Mentor
  
Join Date: Mar 2006
Rookie Year: 2005
Location: Noblesville, IN
Posts: 1,427
efoote868 has a reputation beyond reputeefoote868 has a reputation beyond reputeefoote868 has a reputation beyond reputeefoote868 has a reputation beyond reputeefoote868 has a reputation beyond reputeefoote868 has a reputation beyond reputeefoote868 has a reputation beyond reputeefoote868 has a reputation beyond reputeefoote868 has a reputation beyond reputeefoote868 has a reputation beyond reputeefoote868 has a reputation beyond repute
Re: lightweight, inexpensive speed controllers
Quote:
Originally Posted by yash101 View Post
Also, using a linear voltage regulator at those currents would cause the magic smoke of death to puff out of the regulator. Powering my RasPi from an LDO gets the chip so hot, I have it connected to the aluminum chassey of the robot for a ginormous heat sink!
Depending on the current draw of the controller, as well as the supply voltage of the battery, a low dropout regulator may be just fine. Basically what you need to remember is the difference in the battery voltage and supply voltage is just waste at the linear regulator.

If you have a 12V battery with a 5V linear regulator, drawing 700mA from it will cause it to act as a 4.9W space heater (gets hot very quickly).
If you have a 7.4V battery with a 5V linear regulator, drawing 50mA will only waste .12W, which is much more manageable from a power dissipation perspective.
__________________

Be Healthy. Never Stop Learning. Say It Like It Is. Own It. Like our values? Flexware Innovation is hiring!. We're looking for Senior Automation, Software, and System Engineers. Check us out!