D to A converter for dc motor drive.

Discussion in 'The Projects Forum' started by lam58, Apr 10, 2014.

  1. lam58

    Thread Starter Member

    Jan 3, 2014
    Hi, I'm doing a project where we have to design a small electric car to race around a track that follows a 20kHz 1 amp ac current carrying wire. At the moment we're using an arduino to control the motors. We currently have two designs for the D to A and power amps show in the figures below. I designed the original summing amp which theoretically worked fine, however, according to my team mate it was 'rubbish' because it didn't work when connected to the motors and he designed another type of D to A and power amp. Turns out that the reason it didn't work was because the he put the voltage regulator on the arduino board we soldered the wrong way around.

    Unfortunately both my team mates have decided to stick with the second D to A. Basically I'm wondering if someone could have a look at both designs and perhaps if you can be bothered simulate them and tell me which design is better.

    I'm not bothered if the second design is better because I just want to win the race, I just feel it's a bit unfair that without the D to A and power amp that I designed I don't have much to contribute to the end product.

    Thanks in advance.

    Note: My design schematics are the ones with Circuit lab, lam58/mOUSE CONTROLLER in the black bit at the bottom, and the schematic with the pulse simulation above. There is a 100nf capacitor between the summing resitors and input to the 741 op amp.

    Also I forgot to add that the dc motors can take a max of 6v.
    Last edited: Apr 10, 2014
  2. shteii01

    AAC Fanatic!

    Feb 19, 2010
    Arduino usually has DAC on the board.
  3. lam58

    Thread Starter Member

    Jan 3, 2014
    Yeah, but we're using the digital outputs of the arduino.