rs14smith
Member
There are a number of ways to make a high side driver that's required for Q1 and Q3, but generally they are either an IC or a number of discretes.
Here's an example:View attachment 39323
I found it at: **broken link removed**. They don't tell you how to get VGH, which should be 7-12 volts above your top power rail, or in your case it would be 19-24 volts. It needs to have a generous peak current capability (0.1uF or more) but only needs to provide a few mA continuous. If you change R7, R10, and R11 to be 33k, it should still be fast enough for your circuit since you aren't changing directions frequently or rapidly.
[edit]The gate voltage should be independently, you can't hook two gates together.[/]
I wish I could offer a simpler solution, but this is why for one-offs I use the slightly more expensive P-channel MOSFETs instead.
In your application, I would seriously consider small relays.
Yeah this seems to be becoming more and more complicated using the FETs to switch the polarity for the motor the more I learn what's needed to make this particular circuit work.
I'm a bit new to relays in general, as I've never worked with them, but how much simpler would that make my circuit compared to the one I have now? Reason I ask is, I'm still in the prime state of my project, so this is the time to make major changes if needed, so if I need to simply ditch my current circuit and go with a easier more simplified version, then that's what I'll do