LB1668 SANYO [Sanyo Semicon Device], LB1668 Datasheet - Page 6

• Manufacturer Part Number: LB1668
• Description: Two-Phase Unipolar Drive Brushless Motor Drivers
• Manufacturer: SANYO [Sanyo Semicon Device]

Automatic Recovery Circuit C-Pin Voltage
1. While the blades are turning, the capacitor is charged with a current of about 3 µA (typical), and C is discharged by
2. When the blades lock, the capacitor is no longer discharged, and the voltage across the capacitor increases. The
3. When the output is turned off, the capacitor is discharged at about 0.44 µA (typical). When the capacitor voltage falls
4. If the lock is cleared at the point the capacitor voltage reaches V
pulses that correspond to the motor speed.
output is turned off when that voltage reaches 0.8 V
under V
turned on at this time.) These operations, i.e. items 2. and 3., are repeated with a ton:toff ratio of about 1:6 to protect
the motor.
on.
TH
2, if the lock state is not yet cleared the capacitor continues discharging until V
LB1668, LB1668M, LB1667, LB1667M
IN
.
TH
2, motor rotation is started by turning the output
TH
1. (Note that the output is
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