[Ito-Brazil] pointed out N-Labs simple current limiter for stepper motors. A current limiting system will let you run stepper motors at higher speeds, with greater torque and efficiency without overheating. This particular design is meant to improve upon the common L/R and Chopper drivers. It can handle high voltages without using large resistors and is high performance without using expensive ICs.
You got to be kidding!
The guy is using linear current source to limit the current. What is new about it? It will work for steppers found in floppy disk drives. What about motors that require few amps per phase? Let’s say a motor with 5A 2V windings. And a power supply of 24VDC. Well, 22V has to be droped across the current source. 22 x 5 = 110W. This circuit has to dissipate 110W per phase while the motor dissipates 10W per phase. Very efficient approach, obviously.
That is the reason why choppers are used.
The guy is clueless.