FAN8400D Fairchild Semiconductor, FAN8400D Datasheet - Page 9

• Manufacturer Part Number: FAN8400D
• Description: 3-phase BLDC Motor Driver With PLL
• Manufacturer: Fairchild Semiconductor

Application Information
1. Output Block
• 3 Phase power transistor and free wheeling diodes
• Reverse active type upper side diodes and parasitic lower side diodes
• full wave current linear drive with current feedback
• Connection with external capacitor to prevent voltage spike and oscillation by current drive
• Output transistor commutation by "Winner takes all" method
• Built in over current limit (OCL) circuit
2. Hall AMP Block
• Detection of rotor position using 3 phase hall sensors
• Determination of output commutation by hall signal
3. AGC Block
• This block is remained output amplitude.
• It is controlled by envelope through hall signals.
NOTES:
V
H
H
4. Speed Control Block
• Digital phase locked loop (PLL) circuit
• Generating error pulse between rising edge of clock and falling edge of FG signal.
• High precision stable speed control
AGC
NI
I
is hall inverting voltage.
is hall non inverting input voltage.
is voltage of AGC output.
Hall U
H
H
H
L
L
L
Hall V
H
H
H
L
L
L
Hall W
H
H
H
L
L
L
V
AGC
Output U
M [M]
M [M]
-------------------- -
H
L [H]
L [H]
H [L]
H [L]
NI
1
–
Forward torque [ Reverse torque]
H
I
Output V
M [M]
M [M]
L [M]
H [L]
L [H]
H [L]
FAN8400D (FAN8400BD3)
Output W
M [M]
M [M]
H [L]
H [L]
L [H]
L [H]
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