200w for PMDC motor that is 12/24Vdc(Im running this with 12V) and 800W series motor with 48Vdc though I plan to run it on 24Vdc...the current tolerance for this one is 16A.....

 

Sure, they're cheap. They're getting mighty "long in the tooth" though.

With the amount of current you're switching, it would be a good idea to keep your switched circuit portions short and thick, for low resistance and inductance. If you're using a number of MOSFETs in parallel, that will be pretty hard to do.


I mean turning just ONE of the low-side MOSFETs on continuously, and switching the high-side MOSFET on and off for PWM. You might have problems trying to keep a high-side MOSFET on continuously.

The problems you'd have with shoot-through would only occur when you change the direction of the motor from forward to reverse or vice-versa. But if you turn the MOSFETs OFF and wait for a period of time sufficient to discharge the gate charge completely (not long; 1mS would likely be enough) then you could run the motor in the opposite direction.

Be mindful about sudden motor reversal. This will place very heavy current demands on the bridge, much worse than if the rotor of the motor were locked (stalled).

Hi SgtWookie.

I'm trying to absorb all the info on the IR2110, as I'm building a robot running on a pair of geared conveyor belt motors, but I'm a newbie no doubt.

I hope this doesn't go back on ground already covered, but checking the forums, I learn a lot, but still don't quite get it. I've been tearing my hair out breadboarding the bridge circuit, but I'm beginning to reckon its not the bootstrap circuit that's really the issue, but the signals I put in.

I need to get my head around the actual driving of the entire circuit, so correct me if I'm wrong:

High-side inputs of both chips have PWM running to...BOTH High Inputs constantly, doing the whole charging of the bootstrap and the easier running you mention.... and then the low-side inputs become enables for either side of the h-bridge?

I've also seen another issue I don't 100% understand, and that is, COM and VSS: to couple, or not to couple? Practically in a circuit running of 12v battery, what should be done about the grounds of the 5v supply and the 12v main supply?

Really appreciate the help you have given everyone already on this subject.