A3967
STEP
INPUT
Microstepping Driver with Translator
Half Step Operation
MS1 = H, MS2 = L, DIR = H
100%
70.7%
PHASE 1
CURRENT
–70.7%
–100%
100%
70.7%
PHASE 2
CURRENT
–70.7%
–100%
Dwg. WK-004-18
The mixed-decay mode is controlled by the percent fast decay voltage (VPFD). If the volt-
age at the PFD input is greater than 0.6VCC then slow-decay mode is selected. If the volt-
age on the PFD input is less than 0.21VCC then fast-decay mode is selected. Mixed decay
is between these two levels.
Allegro MicroSystems, Inc.
11
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com