I have a DIY stepper driver (see attached file H_Bridge3.jpg)
Note: That schematic has an error. The driver chip should actually be the TC4427 (Non-Inverting). I discovered this after trying it with the TC4428 and eventually figuring out that that was the “Complimentary Output” version and not the "Non-Inverting " version. After obtaining the TC4427 , the circuit functioned correctly. This driver can handle up to 20A (although my steppers only draw 0.5A).
I have several RAMPS A4988 drivers that work fine with my steppers, but I would like to upgrade my DIY H-Bridge driver by adding a “Front-end” circuit that will convert my driver to a driver
that accepts only two inputs STEP & DIR instead of 4 inputs (A,B,C,D). I understand that the main difference between my DIY driver and the RAMPS A4988 is that the RAMPS is a “Chopper” type driver.
I have three questions:
1- Would adding a logic circuit that accepts STEP & DIR and outputs A,B,C,D , like this one:
make my DIY h-bridge driver a “chopper” type ?
2- Is there any other circuit that will perform the same logic conversion as the one shown ?
3- Is it possible to modify my DIY driver to convert it to a "chopper " type and if so how ?
I have many years of on the job experience as an Electronics Engineering Tech so building circuits is not a problem.