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SN74LVC4245A: SN74LVC4245A question

Part Number: SN74LVC4245A

Hello,i want to convert the signals from 3.3v given by the microcontroller to 5v to drive a lcd,but i have one servo motor and two esc(electronic speed control) who also want the signals at 5v.

I saw many voltage Translation / level Shifters and i decided to use SN74LVC4245A.I will have some problem in driving the servo motor and esc with this level shifter??

Thanks.

  • Hi Thanos,

    It will depend on voltage and current requirements at the servo motor and ESC. The SN74LVC4245A can maintain ~4.3V output while sourcing ~24mA (derived from VOH on electrical characteristics table) on a single channel, however the total current sourced must be less than 100 mA (absolute max table).

    You also can't drive the outputs above VCCA + 0.5V or below -0.5V, so connecting directly to a motor would likely be a problem (protective external diodes can be added to avoid this problem)


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  • In reply to Emrys Maier:

    Thank you for your response,the truth is that I do not know on requirements in current the "signal" pin of servo motor and esc?
    How can i learn it?

  • In reply to Thanos Sig:

    The motor and ESC should have some kind of datasheet or at least specifications to indicate requirements for inputs. I'm afraid you will have to contact the manufacturer if they don't publish something directly.


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  • In reply to Emrys Maier:

    It will be ok.
    I want to have a direction from it B to A(3.3v to 5v) so it should be the pins "oe" and "dir" connect in the gnd,correct?
    Apart from decoupling capacitors It needs something else??
  • In reply to Thanos Sig:

    From section 9.4 of the datasheet, tying both OE and DIR to ground will result in operation 'B data to A bus' -- you are correct.

    No, nothing else is required.


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  • In reply to Emrys Maier:

    Fine,thank you very much for your help.

    Thanks.