Bidirectional DC motor

Discussion in 'The Projects Forum' started by lihle, Nov 30, 2010.

  1. lihle

    Thread Starter Active Member

    Apr 12, 2009

    i need your help to identify where the problem is. i am currently trying to drive a DC motor using 9V for two direction and i am using the full h-bridge. i connected it as shown in figure 6 (attached datasheet). when i set the forward direction by setting pin 10 to 5V and pin 12 to 0V the motor cont move. I am using the L298N. i have not put the protecting diodes as shown in the circuit.

  2. beenthere

    Retired Moderator

    Apr 20, 2004
    You might want to get the data sheet for an L297. That is the IC that drives the L298.

    To learn why, read the material at this link -

    If that is a straight DC motor, ignore the stuff about a stepper. There are at least 4 inputs that have to be satisfied to make the 298 work.
    Last edited: Nov 30, 2010
  3. t_n_k

    AAC Fanatic!

    Mar 6, 2009
    Have you checked that all the other inputs to the driver are correctly connected and at the appropriate voltage levels? Particularly pins 11 & 15...?
  4. SgtWookie


    Jul 17, 2007
    The L298 will drop quite a bit of voltage across itself (~4v), even with a 1A load.
    If you are using a 9v supply, then almost half the power is getting dissipated in the L298.

    L298's need LARGE heat sinks. Otherwise they will burn up almost immediately.

    They also need a 5v supply for logic. If you tried using 9v for the logic supply, you have destroyed the IC.

    If you are trying to power it using a 9v "transistor" battery, you're wasting your time.