Hi all,
I'm a Mechanical Engineering underghraduate that got stuck with the job of creating a triple half bridge motor driver for some hobby BLDC (A2212) motors.
The motors have a max stall current of 10 amps at 12 volts and as such I am trying to make all of my components meet or exceed that rating. Though these motors are just used to launch ping pong balls so I expect they're just going to be driven at the no load current of 0.5A.
My problem is that I initially purchased some L6385E drivers for the fets so I wouldn't have to deal with P-channels and N-channel combinations. This hasn't worked out well for me as I've had a ton of trouble with these drivers, the nail in the coffin for them is that we've switched to a Teensy 3.1 for control and these drivers will not take 3.3v logic input.
My current situation is that I have a boost converter to supply high voltage from my main 12v power supply and I would like to still use my N-Channels (FQA32N20C) in both high and low positions. I think this is possible because I have the boost converter left over from trying to get the l6385's to work so I have the high voltage needed to turn on the high side N-Channels.
What I'm currently thinking is attached as test-driver.png. I've been looking online and it seems that people use a similiar circuit but with Q2 and Q3 reversed. I don't quite understand why that is. Wouldn't that invert the logic signal and never fully turn on the low side pnp? What am I missing?
Given that I already have 2 voltage sources, would my test-driver work? How could I make it better? Keep in mind that Vin is about 20v and VDD is 12v, I have no idea about naming conventions so I apologize if this is completely against the norm. The lines on the left are 3.3v login input and the single line on the right is the motor output.
I technically have no budget left but if anyone has a suggestion of a cheap component that would greatly simplify this, please feel free to suggest. I am pretty sick of IC's from st electronics though.
I'm a Mechanical Engineering underghraduate that got stuck with the job of creating a triple half bridge motor driver for some hobby BLDC (A2212) motors.
The motors have a max stall current of 10 amps at 12 volts and as such I am trying to make all of my components meet or exceed that rating. Though these motors are just used to launch ping pong balls so I expect they're just going to be driven at the no load current of 0.5A.
My problem is that I initially purchased some L6385E drivers for the fets so I wouldn't have to deal with P-channels and N-channel combinations. This hasn't worked out well for me as I've had a ton of trouble with these drivers, the nail in the coffin for them is that we've switched to a Teensy 3.1 for control and these drivers will not take 3.3v logic input.
My current situation is that I have a boost converter to supply high voltage from my main 12v power supply and I would like to still use my N-Channels (FQA32N20C) in both high and low positions. I think this is possible because I have the boost converter left over from trying to get the l6385's to work so I have the high voltage needed to turn on the high side N-Channels.
What I'm currently thinking is attached as test-driver.png. I've been looking online and it seems that people use a similiar circuit but with Q2 and Q3 reversed. I don't quite understand why that is. Wouldn't that invert the logic signal and never fully turn on the low side pnp? What am I missing?
Given that I already have 2 voltage sources, would my test-driver work? How could I make it better? Keep in mind that Vin is about 20v and VDD is 12v, I have no idea about naming conventions so I apologize if this is completely against the norm. The lines on the left are 3.3v login input and the single line on the right is the motor output.
I technically have no budget left but if anyone has a suggestion of a cheap component that would greatly simplify this, please feel free to suggest. I am pretty sick of IC's from st electronics though.
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