What exactly is wrong with the all in one boards for a beginner machine? It works great on my CNC3040, although I realize it is slow.
Oops, I didn't realize this thread was 9 pages long I only read the first one!
For a 'beginner machine' clearly they serve a useful introductory purpose, however having used both performance wise there's just no comparison. I guess the risk is people may be put off CNC all-together by the poorer performance and faults if they occur.
Briefly, most of the all-in-one boards I've seen (TB6560 is a good example) use either one or two single ICs which contain the 8 MOSFETs required to drive a stepper motor in bi-polar configuration. The good single drivers use 8 individual MOSFETs, which has numerous advantages. The main one is all these H-bridge ICs tend to have much lower voltage ratings which very severely limits performance, so people often try to push them outside the ratings resulting in premature failure. Often they are sold with cheap stepper motors that have a high inductance, so actually require an even greater voltage. In addition to this the current ratings are generally lower - I don't think there are any available which will deliver the 4.2A required for a 3Nm stepper motor, so again the torque can be limited unless the machine/motors are small.
For single MOSFETs there's a much greater choice available, so you can get ones with better ratings which helps to lower the heat dissipation and other useful characteristics. A significant advantage is the controller has full control over the switching of the 8-MOSFETs - this makes it possible to add features such as resonance damping and vector current control which improve high-speed torque, so you get more torque from the same motor.
Clearly there's no definitive answer, each machine is different...but in general I wouldn't advise getting them.
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