The invention discloses a stepping motor 
subdivision driving device with 
current vector constant 
amplitude control, which comprises an RS232 interface circuit, an optocoupler isolation circuit, an LED indication circuit, a 
voltage and current protection circuit, a 
subdivision driving power supply circuit, a main 
control unit, a power  The drive circuit, two-phase 
stepper motor and current detection and conditioning circuit, the RS232 interface circuit, optocoupler isolation circuit, LED indicator circuit, 
voltage and current protection circuit, 
subdivision drive power supply circuit and current detection and conditioning circuit are respectively connected with the main 
control unit  connection; the main 
control unit, the power drive circuit are connected to the two-phase stepping motor in sequence, and the power drive circuit is connected to the current detection and conditioning circuit in sequence.  The 
current vector constant-
amplitude control stepping motor subdivision drive device of the present invention can overcome the defects of poor adjustability, low control precision, low reliability and poor 
repeatability in the prior art, so as to achieve good adjustability and control  The advantages of high precision, high reliability and good 
repeatability.