1. Engineers
    “We are creating a common platform for every engineer in the world"
    Are you a part of it yet?

    Start Now - It's FREE
    Dismiss Notice

l293d motor driver IC help

Discussion in 'Robotics | RC | Automation' started by pratik20990, Dec 29, 2009.

  1. pratik20990

    pratik20990 Apprentice

    I am using L293D motor driver for line follower which has the following pin configuration-
    In this at Pin no. 8 we have to apply the voltage at which we want to drive the motors, say, 9V. I want to ask that how can we apply that voltage at a single pin when the rest of the circuit is operating at voltage less than 5V.
  2. silverscorpion

    Engineering Discipline:
    Electronics & Telecommunications
    Well, I dont get your question.. What's the problem in giving two different voltages to 2 pins in the same IC??

    Pins 1 and 9 (Enable pins) are to be connected to 5V. And pins 8 and 16 are to be connected to the same source
    which is used to run the motors. Meaning, if you use 9V to run the motors, connect the pins 8 and 16 to the
    +ve of the 9V supply . Ground the -ve of the supply. That's all.. What's confusing here??

    Oh, if you're asking how you get 9V into the ckt from nowhere, you can always use a voltage regulator. Get a 7809 and
    give 12V from a normal 12V battery to it. It'll regulate it to 9V. Give that 9V to pins 8 and 16. Is it Clear?? :):)
  3. pratik20990

    pratik20990 Apprentice

    Thanks for your help. You have nearly understood my question but I still have some doubt.
    I am making the circuit on a breadboard which has AT89S52 IC, L293D IC and 7805 voltage regulator. I am using a 9V battery input to 7805 which converts it to 5V. Now, if I use another 9V battery to directly give input to pin 8 of L293D by its positive terminal then can I ground the negative terminal by just connecting it to ground of that same breadboard. Will the circuit be complete then and will it work?:confused:

    Please reply....:rolleyes:
  4. dossdss

    dossdss Apprentice

    Engineering Discipline:

    i know am replying too late for the post...:eek: but it may help to those who need to read it....

    actually i want to correct that in l293D
    pin8 = that voltage at which you want to drive the motors and
    pin16= supply vtg for the chip, that is 5V. not same as pin 16.
  5. dossdss

    dossdss Apprentice

    Engineering Discipline:

    yes the negative terminal of the other battery has to be connected to the ground of the same circuit.

Share This Page