SA5664 Datasheet, PDF (6/12 Pages) Silan Microelectronics Joint-stock – 3-PHASE SPINDLE MOTOR DRIVER FOR CD-ROM

SA5664
Rotation
EC<ECR
Regular
EC>ECR
Stop
We can determine the value of input-output gain GEC by RNF resistance, and calculate it with the following
formula. GEC=0.325/RNF [A/V] (GSW=L)
GECM=0.65/RNF [A/V] (GSW=OPEN)
GECH=1.40/RNF [A/V] (GSW=H)
Torque limit current ITL can be calculated by ITL=0.35/RNF [A]
The input range of ECR and Ec is 0.5 V ~ 3.3 V (RNF = 0.5 ¡).
(3) Power save
When power save function is activeˈall power TRs turn off.
(4) Reverse detection
EC
ECR
Fig.3
High Active
A
H1+
D
Q
H1-
H2+
CK
H2-
D-F/ F
l When the output of the AND Gate, A is High, the output of the Driver becomes open and the motor stops.
l When in the state of the forward rotation, the D-F/F output Q is LOW and the control input is EC < ECR, so
the motor rotates normally.
l At Forward rotation, if the 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
High and the AND Gate output, becomes High. Thus detective circuit operates, make the output of the
Driver becomes open and the motor stops.
Forward rotation at EC<ECR.
Rotating speed is decreased due to reverse torque at EC>ECR.(forward)
When motor rotates in reverse, reverse detection operates and output become open.
Rotating reverse at short time due to motor inertia.
Stop
HANGZHOU SILAN MICROELECTRONICS CO.,LTD
Http: www.silan.com.cn
REV:1.1 2005.08.09
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