HA13614FH Datasheet, PDF (14/26 Pages) Hitachi Semiconductor – Combo (Spindle & VCM) Driver

HA13614FH
Commutation Timing of the Spindle motor
U
V
W
B-EMF
CT
PHASE
(EXTCOM=0)
*1
PHASE
(EXTCOM=1)
OUTPUT
PWM
B-EMF
PWM
PWM
Vpss
Vpss/2
GND
tspndly
*2
*3
IU
0
tsrctl
commutation
time
Note: 1. In the case of external commutation mode (EXTCOM=1), the signal PHASE will toggle at every B-
EMF zero-crossing, and selected the internal commutation mode (EXTCOM=0), the PHASE will
have the same period as B-EMF of the spindle motor.
2. This is delay time by pre-LPF of the B-EMF amplifier. This delay time can be adjust by the value
of external filter capacitor C101, C102. To get the maximum driving efficiency of the spindle
motor, these capacitor value should be chosen as equation (17) in the “External components”
section.
3. The slew rate of every commutation timing is controllable by changing the SRCTL1, SRCTL2 and
SRCTL3 in the serial port.
Figure 9 Commutation Timing of the Spindle motor
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