Shop OBEX P1 Docs P2 Docs Learn Events
Need Help! Can SN754410 handle 40RPM 12V 22 oz-in Torque 160mA DC Gearmotor — Parallax Forums

Need Help! Can SN754410 handle 40RPM 12V 22 oz-in Torque 160mA DC Gearmotor

bilalofnedbilalofned Posts: 1
edited 2011-04-04 14:13 in Robotics
I am planning to build a Pan Tilt mechanism for my video Camera JIB. I have selected 40RPM 12V 22oz-in 160mA DC gear motor from servocity [http://www.servocity.com/html/40_rpm_gear_motor.html] along with additional gear box with a ratio of 8.45:1 [http://www.servocity.com/html/gearmotor_gearbox.html]. On the controller side I have selected SN754410 as motor driver IC which supports 1A current per motor with peak current up to 2A per motor.

My question is, is SN754410 capable enough to handle this configuration of motor or there should be some other work around to it?

I would like to hear from experts.

Br
Bil

Comments

  • Duane DegnDuane Degn Posts: 10,588
    edited 2011-04-01 15:56
    I've used the SN754410 chip in several projects. I'd be inclined to think it would work with this motor. The problem is SevoCity gives the stall torque but not the stall current.

    I've recently been told that one can stack two SN754410 chips on top of each other to double the current. This might be an option.

    Hope this helps until an "expert" answers.
  • ercoerco Posts: 20,256
    edited 2011-04-02 10:58
    Stall current can be exceeded when a motor reverses quickly, especially if the load has mass & momentum (like a camera). And I've also seen driver ICs stacked & soldered to increase current capability. Not elegant, but it works!
  • RobotWorkshopRobotWorkshop Posts: 2,307
    edited 2011-04-02 11:12
    There is a lot more details in this thread:

    http://forums.parallax.com/showthread.php?130365-%28Need-Advise%29-RC-ESC-or-L298&highlight=sn754410

    You can stack those chips and I usually add a DIP heatsink on the top chip (with some heatsink grease) which can cool both chips.

    Robert
  • ercoerco Posts: 20,256
    edited 2011-04-02 15:33
    from http://www.junun.org/MarkIII/Info.jsp?item=60

    This popular H-Bridge chip can be used to drive 2 DC motors, solenoids, relays, or other inductive loads with a peak current of 2 amps and a continuous sustained current of 1.1 amps per driver. Supports load voltages from 4.5V to 36V.
    Contains internal protection diodes and thermal overload protection. Two SN754410NE chips may be stacked to double the current capacity.

    Sounds up to it, especially if you stack two.
  • RobotWorkshopRobotWorkshop Posts: 2,307
    edited 2011-04-02 16:41
    This is the way I build them.....

    Robert
    Stacked.jpg
    767 x 765 - 83K
  • Duane DegnDuane Degn Posts: 10,588
    edited 2011-04-04 13:30
    Robert,

    That's a nice looking heat sink. It looks like it contacts both chips.

    Do you have a supplier and part number for those?

    It looks like you can still use the chip in a socket. I was afraid I'd have to solder them in place when I used the piggy back method.

    Duane
  • RobotWorkshopRobotWorkshop Posts: 2,307
    edited 2011-04-04 14:13
    I'm not sure where to get them in gold any more but you can easily pickup the same thing in black from Mouser:

    http://www.mouser.com/ProductDetail/Aavid-Thermalloy/580200B00000G/?qs=sGAEpiMZZMttgyDkZ5WiujXDzyHJDjizpZf%2fI3f18mc%3d

    Just slip the heathsink on the top chip first. Then put a little heat grease on the top of the bottom chip before sandwiching them together and soldering. If you solder just where the leads meet then you can just plug it in a socket so it can easily be removed.

    There is also a 40-pin version of this Heatsink which would work well with the Propeller.

    Robert
Sign In or Register to comment.