KA3011BD Fairchild Semiconductor, KA3011BD Datasheet - Page 11

• Manufacturer Part Number: KA3011BD
• Description: Motor / Motion / Ignition Controllers & Drivers
• Manufacturer: Fairchild Semiconductor
• Type: 3 Phase Brushless Spindle Motor Driverr

Specifications of KA3011BD

• Operating Supply Voltage: 5 V
• Mounting Style: SMD/SMT
• Package / Case: SSOPH-28
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

KA3011BD
6. REVERSE ROTATION PREVENTION
• When the output of the OR Gate, A is LOW, it steers all the output current of the current sense Amp to the Gain Controller
• As in the state of the forward rotation, the D-F/F output, Q is HIGH and the motor rotates normally. At this state, if the
zero. The output current of the Driver becomes zero and the motor stops.
control input is changed such that EC>ECR, then the motor rotates slowly by the reverse commutation in the Driver. When
the motor rotates in reverse direction, the D-F/F output becomes Low and the OR Gate output, becomes LOW. This
prevents the motor from rotating in reverse direction. The operation principle is shown in the table and the flow chart.
At the moment that the motor rotates in reverse, the reverse rotation preventer makes the output power transistor open.
E
H2+
H2
H3+
H3
E
CR
C
Rotation
Reverse
Forward
+
+
+
Rotating speed is decreased due to reverse torque at E
H2
H
L
CK
D
D-F/F
Rotating reverse at short time due to motor inertia
Q
Stop within 1/6 turn reverse rotating
H L
H L
Forward rotation at E
H3
A
Low Active
11
D-F/F
(Q)
H
L
C
< E
C
>E
CR
Controller
Current
Sense
Amp
Gain
CR
. (Motor still rotates forward)
Forward
E
Reverse rotation preventer
C
<E
-
CR
Driver
Brake and stop
E
C
>E
-
CR
M