I am using T.I SN754410 IC to drive bi-directional, I discover the mean output voltage of one side is higher than the other side output. I check thru the oscilloscope, the mean voltage from one side is about 4.5V, the other side mean is about 2.1V. So one side of the motor is working and the other side not working, despite I use the same motor and same PWM to enable both side. Can someone help why is it like this ?
I have used the 754410 chips many times and never have I seen that problem. So I think that there is something in your wiring or code that is not right. Can you post a schematic of your setup?
The enable Pin of the L293D or SN754410 motor driver connect to ATTiny45 PWM output pin.
When I measure the enable pin without the ATTiny45 IC, the enable Pin of L293D have 2.1V.
According to the spec, the max Low of Enable pin is 1.5V, why this IC give me 2.1V. I suspect this 2.1Vwill corrupt my ATTiny program because the PWM will have 0-5V.
But when I change the new SN754410 IC,this IC by default give me 2.1V. I am curious is this normal?
Have you got a spare SN754410 so you can check if one of them is damaged?
And you need to post a diagram showing how everything is connected. Verbal descriptions of wiring are too easy to misunderstand.
...R
I found the issues, the issue is the ground is noisy, it is not 100% grounded. I re-soldered every pins and the problem is gone.