FAN8729 Fairchild Semiconductor, FAN8729 Datasheet - Page 14

• Manufacturer Part Number: FAN8729
• Description: Motor / Motion / Ignition Controllers & Drivers BLDC+4CH BTL
• Manufacturer: Fairchild Semiconductor
• Type: Spindle Motor Controllerr

Specifications of FAN8729

• Operating Temperature Classification: Commercial
• Package Type: PQFP
• Operating Supply Voltage (min): 4.5V
• Operating Supply Voltage (max): 13.2V
• Operating Supply Voltage: 4.5 V to 13.2 V
• Supply Current: 16.5 mA
• Mounting Style: SMD/SMT
• Package / Case: QFPH-48
• Lead Free Status / RoHS Status: Compliant

6. Calculation of Gain & Torque Current
• Toque limit circuit limits the current of spindle motor.
• Driver amp circuit limits the current of spindle motor by comparing the voltage detected from R
• Output current of the motor can be limited by adjusting the R
• Maximum output current of motor is found as follows;
• VMAX within IC is fixed at 350mV.
• Gm of torque sense amp is set to 0.71.
from torque sense map.
Io
[
mA
]
ECR
ER
=
V
Rcs
max
-
+
=
Gm
350
Rcs
mV
Current / Voltage
Convertor
Absolute
Values
Vin
-
+
VM1
current limiting
R1
Max. output
VM1
+
-
Vmax
-
+
+
CS
Driver
value.
Feedback loop
Negative
Commutation
H1
Transistors
Distributor
Io
Power
VM1
H2
CS1(Pin11)
Rcs
H3
-
Vs
+
Current sense
W
U
V
Output
Io
CS
and the voltage output
FAN8729
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