Hey guys,
I am designing a circuit for DC motors. I just need your opinion on something before I go and print the PCB
I just want to ask you if I need to put a resistor on pin 3 of the IR2110 to limit the current?
especially that the motors also run on 12V.
On the PCB the 12V on pin 3 of IR2110 is very close to pin 2 of Q5.
would it be a problem if I connect them together? and if so, is it better to have a resistor (~100ohm??) between pin 3 and 12V?

Thank you 3 is very close to pin 2

 

Don't have a resistor but you must have a capacitor from pin 3 to pin 2 of both U10 and U13. Very close to the IC. 100nF ceramics would be good.

I take it that this is the same 12V supply as the top of the H bridge. Should not be a problem. The 12V supply also needs a large electrolytic capacitor. 2000uF or so depending on the current draw of the motor.

 

I have three motors. 1 draws at full load 5A. one motor draws 0.17A and one draws 1 or 2 A

 

I see you have the Hin and Lin pins connected together.
My thought is that will not work. You would then be driving both sides the same.
Have a look at connecting one Hin to the Lin of the other side, and see how that works. You need to drive one side high and the other low to get the motors running.
Both high or low will not drive them.

 

I see you have the Hin and Lin pins connected together.
My thought is that will not work. You would then be driving both sides the same.
Have a look at connecting one Hin to the Lin of the other side, and see how that works. You need to drive one side high and the other low to get the motors running.
Both high or low will not drive them.

Oh yes true. I did that by mistake. Thanks a lot