5
CIRCUIT OPERATIONAL DESCRIPTION
) Motor Drive IC: AT5888S
The AT5868S is a 5-channel BTL driver IC for driving the motors and actuators in products
such as CD-ROM/DVD-ROM/DVD-Player drives. Two of the channels use current feedback to
minimize the current phase shift caused by the influence of load inductance. Driver IC gener-
ates the focus signal and the tracking signal for pick-up actuator, the sled signal for feed,
spindle signal and the load signal for opening and closing of the tray. The focus signal, the
tracking signal, the sled signal and the spindle signal are input into each relaxant port of
the drive IC(in the order of No. 26 pin, 23, 4, and ) and set the gain amplification and the
center voltage through the internal OP-AMP and drive on both sides and then the focus sig-
nal and the tracking signal will be output as VOFC+, VOFC- and VOTK+, VOTK- on actuator,
the sled signal and the spindle signal will be output as VOSL+, VOSL- and VOLD+, VOLD- on
each motor. For the load signal the input opening/closing signal is output as VOTR+, VOTR-
through the loading PRE FWD REV circuit.
Motor Drive IC (AT5888S) Block Diagram
Actuator
Driver(6x)
MUTE
Actuator
Driver(6x)
Spindle
Driver(4X)
Sled
Driver(4X)
Thermal
Shut down
+
-
+
-
10K
25K
GND
Vcc2
28
27
26
25
24
23
22
21
20
19
18
17
16
15
8
9
10
11
12
13
14
1
2
3
4
5
6
7
PGND
25K
10K
Vcc1
PGND
Vcc2
Vcc2
Vcc1
Pre-DRV
TRAY
DRIVER
VCTL
FWD
REV
TRB_2
NC
NC
REGO2
TRB_1
REGO1
VOTR-
VOTR+
VOSL+
VOSL-
VOFC-
VOFC+
VOLD-
VOLD+
VOTK-
VOTK+
-
+
-
+
VINSL+
VINFC
MUTE
BIAS
VINTK
VINLD
GND
VCC2
VCC1
10K
25K
15K
10K
- +
+
-
CIRCUIT OPERATIONAL DESCRIPTION
Sm(SANYO_DVD-DX500)051220.indd 5
2005-12-29 8:58:39
