And here I come up with yet another full schematic, and a question.

In the attached typical application circuit, what for are tha caps between Vb/Vs and Vcc/COM, and the diode between these pairs?

 

And here I come up with yet another full schematic, and a question.

In the attached typical application circuit, what for are tha caps between Vb/Vs and Vcc/COM, and the diode between these pairs?

The cap between Vb/Vs plus the diode make up a "charge pump" circuit to give ~10V to the gate when the upper mosfet is on.

The cap between Vc/com is to provide extra voltage to the chip if needed when it is switching.

Your schematic shows a Pmos in the upper switch, it won't work in this type of circuit. Both high and low side mosfets need to be Nmos, when using a half bridge driver.

 

Your schematic shows a Pmos in the upper switch, it won't work in this type of circuit. Both high and low side mosfets need to be Nmos, when using a half bridge driver.

Totally missed that, yes. Which leads to another question: will the same circuit with two NMOS still provide the push-pull functionality needed to drive the motor?

If yes, what would be the purpose of using a p+n configuration as shown in one of the appnotes you referenced (see attachment) -- I was actually trying to repeat that.

 

Just guessing here but, if you used that circuit you wouldn't need an inverter gate to make the high and low signals work. By that I mean, when the high side is on, it automatically shuts the low side off, using one output from the micro. If you had both switches as Nmos, you would need an inverter on one of the gate signals. That would then do the same as one Pmos and one Nmos.

Since I don't use micros I'm just guessing about this.

 

Just guessing here but, if you used that circuit you wouldn't need an inverter gate to make the high and low signals work. By that I mean, when the high side is on, it automatically shuts the low side off, using one output from the micro. If you had both switches as Nmos, you would need an inverter on one of the gate signals. That would then do the same as one Pmos and one Nmos.

Since I don't use micros I'm just guessing about this.

Thank you. I was just wondering about any electrical characteristics of FETs unknown to me, similar to BJT active/saturation modes, but apparently it's just for simplicity.

Since all is figured out, I will be ordering components. I did some research on determining rotor position. Apparently I will not be able to install Hall effect sensors due to construction of the motor I have, so I will use back emf sensing.
Any required circuitry should be possible to do on a separate PCB, since I want the driver operational first.