3-4-L. Motor Driver; Tray Position Detection - Sony DVP-M35 Operation Manual

Disc loading, unloading, and chucking operations are performed with one DC motor. Its
block diagram is dhown in Figure 3-19.

3-4-l. Motor Driver

The system controller IC (ICSOS) controls the open and close of the tray. It monitors the
sensors of the mechanism and
controls the operations of the tray motor via the L G/A IC (1004).
The tray open/close signal is output by 3-state PWM modulation from IC804.
H (5V) = Open
High Z = Stop
L (Gnd) = Close
The tray speed is controlled by increasing/decreasing the PWM duty ratio.
The TRAY FREE signal is used to control the Mute terminal of the driver directly, turn OFF
the motor drive, and free the operations.
During the stop state, the potential difference between the two terminals of the motor is
controlled to OV, while during the Tray Free state, the motor is not controlled at all.
3-4-2.

Tray Position Detection

Tray position detection is carried out by the chucking sensor PHOOl and tray out sensor
SO01 on the TK-47 board. These signals are input to the MB-78 board via the flexible flat
cable, and input to L G/A (IC804) CHUCK @P, and TRAY BP.
The relation between tray position and sensor signals is as shown below:
Mode
Tray out position
Tray operating
Chucking position
<TRAY OUT (CNOOS@)>
H
L
L
<CHUCKING (CNOOS@)>
L
L
H