m56755afp Mitsumi Electronics, Corp., m56755afp Datasheet - Page 5

• Manufacturer Part Number: m56755afp
• Description: Spindle Motor Driver
• Manufacturer: Mitsumi Electronics, Corp.

HALL AMPLIFIER INPUT AND COMMUTATION
The relationship between the hall amplifier inputs voltage and the
motor current outputs is as shown in Figure 2.
Figure 2.
HALL AMPLIFIER INPUT SENSITIVITY SELECT
Figure 3.
SLEEP MODE FUNCTION
Figure 4.
LOW or OPEN
The hall amp
input voltage
minimum is
50mVp-p.
Hall
inputs
Output
current
Hall-Bias off
OPEN or HIGH
120 degree
soft switching
Motor Stop
Bias off
START / STOP
U
V
MODE4
Hw+
120 degree switching
Hall-Bias on
** Io current
W
Motor on
will be shape.
Bias on
The hall amp
input voltage
minimum is
35mVp-p.
HIGH
U
Hv+
GND
V
W
Hu+
U
V
W
SOURSE
SINK
Hall elements
Figure 3 shows the hall amplifier input sensitivity select function.
An user is able to select the sensitivity of a hall amplifier to match
with the hall elements type.
If the output minimum level of a hall elements is a low level as
below 50mVp-p, please connect the MODE4 to GND at external.
In this case, the output current will be shape. If the output minimum
level of a hall elements is more higher than 50mVp-p, please make
the MODE4 to open, then the output current will be commutated
softly.
We recommend that the output level of a hall element is used for
80mVp-p to 120mVp-p and the MODE4 is made to open.
Figure 4 shows the sleep mode function. If the
open or low, the current output will be high impedance and then
the motor will be stop. Also, the IC bias current wil be a slight
current (please make reference the electrical characteristics). At
the same time, the hall bias output will be cut off. When the
goes high, the all of circuits will be available.
W
V
MITSUBISHI <CONTROL / DRIVER IC>
W
V
U
U
FORWARD
EC < ECR
V
U
SPINDLE MOTOR DRIVER
W
W
V
U
M56755AFP
Outer loator
1
REVERSE
EC > ECR
pin [S/S] is set to
1
pin