The L297 Stepper Motor Controller is primarily intendedfor
usewith anL298Nor L293Ebridge driver
in stepper motor driving applications.
It receives control signals fromthe system’s controller,
usually a microcomputer chip, and provides all
the necessarydrive signals for the power stage.Additionally,
it includestwoPWMchoppercircuits toregulate
the current in the motor windings.
With a suitable power actuator the L297 drives two
phase bipolar permanentmagnet motors, four phaseunipolarpermanentmagnetmotorsandfourphase
variable reluctancemotors.Moreover, it handles
normal,wave drive and half step drivemodes. (This
is all explained in the section ”Stepper Motor Basics”).
Two versions of the device are available : the regular
L297 and a special version called L297A. The
L297A incorporates a step pulse doubler and is designed
specifically for floppy-disk head positioning
applications.