L297 Datasheet, PDF (5/11 Pages) STMicroelectronics – STEPPER MOTOR CONTROLLERS

L297-L297D
MOTOR DRIVING PHASE SEQUENCES
The L297’s translator generates phase sequences
for normal drive, wave drive and half step modes.
The state sequences and output waveforms for
these three modes are shown below. In all cases
the translator advances on the low to high transis-
tion of CLOCK.
Clockwise rotation is indicate; for anticlockwise ro-
tation the sequences are simply reversed RESET
restores the translator to state 1, where ABCD =
0101.
HALF STEP MODE
Half step mode is selected by a high level on the HALF/FULL input.
NORMAL DRIVE MODE
Normal drive mode (also called ”two-phase-on” drive) is selected by a low level on the HALF/FULL input
when the translator is at an odd numbered state (1, 3, 5 or 7). In this mode the INH1 and INH2 outputs
remain high throughout.
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