Sony CDPCX-235 Service manual

S®

CD
Changer

Models: CDP-CX235

CDP-CX270
CDP-CX335
CDP-CX400
CDP-CX450

Training Manual

Circuit Description and Troubleshooting

Course: A-122

Sony Service Company

A Division of Sony Electronics Inc ©2000

All Rights Reserved

Printed in U.S.A.

S is a trademark of Sony Electronics

Circuit Description
and Troubleshooting:

Models: CDP-CX235

CDP-CX270
CDP-CX335
CDP-CX400
CDP-CX450

Prepared by: National Training Department

Sony Service Company
A Division of Sony Electronics Inc.

Course presented by _____________________________________

Date___________________________________________________

Student Name ___________________________________________

Table of Contents

Overall Block Diagram 3

Information Gathering 3
CD Playback 3

Power Supply / Display 5

Power Supply 5
Fluorescent Display 7

Power On 11

AC Power Only 11
Power ON 11
Communications IC501 - IC701 11
Communications IC501 - IC101 13

Door Motor Drive 15

Operation 15
Drive 15

Tray Table Motor Drive 21

CD Location & Label Storage 23

Disc Loading Drive 27

Operation 27
Motor Stop 27

Optical Pickup 29

The Laser and Lens 29
Focus Coil 29
Tracking Coil 29

Detector Outputs 29

Servo / Audio Processing Block 31

Servo Block 31
Sled Motor 31
Focus Servo 31

Feedback 15

Tray Table Positioning 17

Tray Table Slots 17
Light Sensors 17

Table Motor Drive 19

Front Panel Rotary Encoder - Operation 19
Direction of Rotation 19
Tray Table Position Sensors 19

Tracking Servo 33
Spindle Motor 33
Audio Block 33

Servo Processing 35

Sled Motor Drive 35
Laser 35
Focus 35
Tracking Servo 35

Spindle Servo 37

APPENDIX

Audio / Display Output 39

Analog Audio Output 39
Digital Output 39
Display 39

Troubleshooting 41

Disc Doesn’t Spin 42
Servo Processing Diagram 43
Focus 44
Disc Won’t Spin Flowchart 45
Disc Spins, But Doesn’t Read the Disc’s

Table of Contents (TOC) 47
RF Output 47
Tracking Servo 47
Disc Spins, But Does Not Read TOC Flowchart 48
Spindle Servo 49

Control A Communications for Additional Features i
Defective Discs iii
Troubleshooting Using the RFO Waveform v
Abbreviations Used in Compact Disc Player vi

No Audio 50

Optical Assembly Tests 51

S Curve Check 51
E-F Balance Check 51
RFO Level Check 52

1

)

CD Mega Changer Product Line (USA

Model Disc List

Capacity Price Cd Mech BD Board List Price Optical Assembly / Part number List Price

All of these numbers sub to 8-848-379-31

2000
CDP-CX235 200 170.00$ CDM-40B A4724029A $76.15 KSS-213BNK / 8-848-379-31 82.12$
CDP-CX270 200 $1,000 CDM-40B A4699163A $112.01 KSS-213B / 8-848-376-01 82.12$
CDP-CX335 300 300.00$ CDM-54-KIBD35E A4724761A $82.12 KSS-213BFN / 8-848-379-31 82.12$
CDP-CX400 400 360.00$ CDM-62-K1BD35A A4724761A $82.12 KSM-213BFN / 8-820-026-03 * 82.12$
CDP-CX450 400 480.00$ CDM-62-K1BD35A A4724761A KSM-213BFN / 8-820-026-03 * 82.12$

*use ’CX335 manual for part number

1999 of spindle or sled motor
CDP-CX225 200 250.00$ CDM-40 A4699038A $112.01 KSS-213B / 8-848-376-01 82.12$
CDP-CX230 200 300.00$ CDM-40B A4724029A $76.16 KSS-213BNK / 8-848-379-31 82.12$
CDP-CX270 200 $1,000 CDM-40 A4699038A $112.01 KSS-213B / 8-848-376-01 82.12$
CDP-CX300 300 360.00$ CDM-54-KIBD35E A4724761A $82.12 KSS-213BFN / 8-848-379-31 82.12$
CDP-CX350 300 480.00$ CDM-54-KIBD35E A4724761A KSS-213BFN / 8-848-379-31 82.12$
CDP-CX691 300 CDM-54-KIBD35E A4724761A KSS-213BFN / 8-848-379-31 82.12$

1998
CDP-CX210 200 CDM-40 A4699038A $112.01 KSS-213B / 8-848-376-01 82.12$
CDP-CX220 200 CDM-40B A4724029A $76.16 KSS-213BNK / 8-848-379-31 82.12$
CDP-CX240 200 CDM-40B A4724029A KSS-213BNK / 8-848-379-31 82.12$
CDP-CX260 200 CDM-40B A4724029A KSS-213BNK / 8-848-379-31 82.12$
CDP-CX270 200 CDM-40 A4699038A $112.01 KSS-213B / 8-848-376-01 82.12$
CDP-CX90ES 200 $1,100 CDM-40 A4699038A KSS-213B / 8-848-376-01 82.12$

List Prices are as of 7/1/00

Introduction

This training manual is based upon the model CDP-CX235 CD Changer.
This model is the entry changer in the “Mega” Changer product line for
the year 2000. The “2” in the model number refers to the 200 disc capac­ity of these Changers. These 200 series models are mechanically com­plex so there are more CD transport and mechanical adjustments to be
made.

The concepts and circuitry in this 200 disc model are similar to the 300
disc CDP-CX300 series and 400 disc CDP-CX400 series CD Changers.
In these larger capacity models, the CD transport and CD mechanism
use fewer parts. As a result, the higher capacity Changers require fewer
adjustments.

Generally, the electrical troubleshooting procedures and test modes out­lined in this training manual can be applied to all of the changer models
listed for the last three years. This is because for troubleshooting pur­poses, they are electrically similar. Mechanically, the 200 disc Changers
use one basic chassis and the 300 and 400 disc Changers use another
chassis so the mechanical adjustments differ.

Model CDP-CX90ES/CDPCX-270

Model CDP-CX235

The board layout of the CDP-CX235 is shown. The bulk of the electronics
are on the rear main board. To its left in the vacant area is the CD mecha­nism housing the optical assembly and servo (BD) board. The small boards
along the bottom of the chassis hold the tray table and disc sensors. The
top illumination board houses 3 LEDs to light the disc compartment when
the CD Changer is powered on.

The model CDP-CX90ES/CDPCX-270 was carried over from the 1998
year because it was the only chassis that had the following major fea­tures:

• A video output for an on-screen display using a TV.

• A front panel jack that permitted a computer keyboard to be plugged

in. This allowed the user to label or re-label each CD slot location
quickly using the keyboard instead of the slower remote control

.

2

3

Overall Block Diagram

At the core of the 200 disc CD Changer is the System Control (Syscon)
IC501. IC501 serves as the interface between the user and the mecha­nism. Before IC501 can respond to the user’s commands for a disc to
play, it must know the following:

· If the Disc door is closed.

· If the CD Mechanism is in the chucked position.

· At which disc slot is the tray table is positioned.
Some of this information is stored in an external memory IC; the remain­der IC501 will have to gather at power ON using the sensors and switches
linked to the Door, Tray Table and Loading Motors.

Information Gathering

Pressing the power ON button causes IC501 to use “IC SW” to switch on
regulator IC506. IC506 apples power to the BD board, which houses the
optical assembly. D+5V is also applied to the LED in the door compart­ment to inform the user power is ON.

After Syscon IC501 turns on power, IC501 accesses its external memory
IC. Data about the disc last loaded in the CD Mechanism is returned to
IC501. The disc label information is output as data to the FL Display IC
for display on the front panel fluorescent tube. If there was no label infor­mation, then just the disc’s number is displayed.

Syscon now takes a series of steps to check the memory information:

Once Syscon IC501 is confident the tray table information is valid, IC501
turns the CD Changer control over to the user by accepting pushbutton
commands.

The user can use the front panel controls to select another disc or play
that one. When Syscon knows the loading motor is in the chucked posi­tion (loading motor switch), the CD can be played.

CD Playback

Syscon IC501 initiates CD play by sending data, clock and latch commu­nications to IC101 on the BD board. This causes IC101 to turn on the
laser, focus, tracking and spindle servos that employ the laser diode, along
with the focus coil, tracking coil, sled motor and spindle motor in the opti­cal assembly.

Once these servos are operating, the disc information (RFO) is output.
RFO is received by Servo Control IC101 which:

• Converts the data back to the original modulation scheme (EFM).

• Error corrects the data (parity error correction).

• Reconstructs its original pattern (CIRC).

• Creates additional digital samples (oversampling) to reduce noise in

the final analog audio.

• Converts the signal from digital to analog form (D/A Converter).

1. Syscon activates the disc door motor to close the door if its corre­sponding switch indicates the door is open.

2. Next, Syscon checks the loading motor switch position to see if the
CD Mechanism is in the chucked position (disc loaded).

• If chucked, IC501 will initiate disc PB to read its TOC.

• If unchucked, IC501 will drive the tray table motor, rotating its discs

past the disc sensors. While the tray is rotating, the tray sensors
inform IC501 of the disc slot location while the disc sensor tells
IC501 if there is a disc present at that slot. The last disc played
according to memory will be loaded and its TOC read (if present).

Analog audio is output from IC101 to the rear panel jacks.

BD BOARD

OPTICAL

PICK-UP

ASSEMBLY

KSS213B

MAIN BD.

-28V

SOURCE

MEMORY

POWER

SUPPLY

FILAMENT

VOLTAGE

A-F

RF AMP

COIL &
MOTOR
DRIVER

FRONT
PANEL
BUTTONS

-13.5V SOURCE
+5V SOURCE

+11.5V

SOURCE

RFO

ERROR
SIGNAL

IC501

SYSTEM

CONTROL

IC101

SERVO

CONTROL/

DSP

IC

SW

IC506REG

/SW

LINE OUT

D

OUT

DIGITAL

OPTICAL

OUTPUT

JACK BD.

IC503
MOTOR
DRIVER

FL DATA,CLK,LATCH

DISC DOOR

LIGHT

D+5V

+7V

RESET

AUDIO
MUTE

M

DOOR

M

TRAY

M

LOADING

IC701

FL DISPLAY

DRIVER

TO BD BOARD

IC401

AUDIO

AMP

MUTE

RESET

FROM

IC506

SWITCH OR

SENSOR

FL DISPLAY

TUBE

DISPLAY BD.

L

R

AUDIO

OUTPUT

(JACK

BD.)

TO DISPLAY BD.

OVERALL BLOCK DIAGRAM (MODEL CDP-CX235)

4

0A122 1251

7/5/00

5

Power Supply / Display

Overview

The power supply stage produces seven voltages when the CD Changer
is plugged into AC. Some of these voltages from the main board power
the FL Driver microprocessor IC701 and the FL indicator tube on the dis­play board.

Power Supply

Power Supply Output

Output Voltage From Destination

1. +11.5Vdc Bridge Rectifier
D501-4

2. 13.5Vdc Bridge Rectifier
D501-4

3. +5Vdc Source Regulator IC504 Syscon IC501 (not shown),

4. +5Vdc Bridge D501-4 &
Zener D508

5. Reset +5V Reset IC505 Syscon IC501 (not shown),

6. 3.7Vac Power Transformer
T901

7. -28V Q501/emitter Reference voltage for the

Regulator/Sw IC506,
+5V Regulator IC504,
Motor Driver IC503.

Audio mute transistors
(Q325/e, Q327/e and
Q425/e), Motor driver
IC503.

FL Driver IC701.
Mute transistors Q325/e,

Q327/e and Q425/e.

FL Driver IC701,
LED Driver IC702 (not
shown).

Fluorescent Display Tube
filament

Fluorescent Display

The positive output of the bridge rectifier is filtered by C501 to become the
+11.5V source voltage.
The negative output of the bridge rectifier is filtered by C502 to become
the –13.5V source voltage.

+5Volt Source

The +11.5V source voltage is reduced and regulated by IC504 to produce
the +5V source voltage for the CD Changer.

+5Vdc

The +11.5V source voltage is reduced by R505 and R508 and applied to

5.1 volt zener diode D508 for shunt regulation. Shunt regulation is when
a device like this variable resistance zener diode is placed in parallel with
the load. The zener diode resistance varies to keep the voltage at the
load reasonably stable.
This +5 volts that is output is used by the mute transistors Q325, Q327,
and Q425 to control the left and right channel audio muting at power ON
and OFF and when plugged and unplugged from AC.
D509 and C505 are used to insure there is sufficient voltage for the mute
operation when the unit is unplugged. C505 holds the +5V for the mute
transistors and diode D509 blocks this voltage from being used by the
loads on the 11.5V line (D509/anode).

Reset +5V

When the +5Volt Source voltage outputs regulator IC504, IC505 creates
a reset pulse using R506 and C507. Each one of these three parts has a
role in creating the reset pulse. When the source voltage is input IC505,
IC505 holds it output LOW for a fixed amount of time dependent upon
IC505’s design. This LOW grounds out C507 at the output. When the
IC505 releases ground, C507 is charged by R506 to +5V.
The reset output of IC505 is applied to the IC501 and IC701 microproces­sors in this CD Changer. Generally, reset occurs when the reset input to
a device is held LOW while power (Vcc) is applied.

+11.5V Source / -13.5V Source

When the CD Changer is plugged into AC, this voltage is applied to the
primary winding of T901. The secondary winding that is center taped
applies 20.6Vac to a four-diode bridge rectifier designated D501 to D504.

L901
NOISE
FILTER
CHOKE

Ω

55

THERMAL
FUSE

MAIN BD.

T901

JACK

BD.

C502

1000

2Ω

D505

Ω

2

Ω

2

+

41

R502

D506
30V

3.7VAC
FILAMENT

VOLTAGE

R501
33k

Ω

-28V

-40V

P

Q501

D507

6.2V

IC505

PST994D
C503
100

+

IC504

REG

TA7805

+

D501-

D504

D509

R505

R508

D508

5.1V
+11.5V SOURCE TO: IC506

REGULATOR,
IC503 MOTOR DRIVER

+

+11.5V

C501

3300

-13.5V SOURCE TO: MUTE
TRANSISTORS Q325,Q327,
Q425 AND IC503 MOTOR DRIVER

C507

R506

SYSCON

IC501/30

C506

C505

+

14 2 3

15 1 1

JOG

BD.

13 3 2

115

+

7 9 9

+5V

SOURCE

(B+)

+5V TO MUTE
TRANSISTORS
Q325/E,Q327/E,
Q425/E

FL701 FL INDICATOR TUBE

1

-28V

65

R701

100k

-28V

7

RESET

+5V

+5V

2.5V p-p

OSC.2.48MHz

WORDS

GRIDS 1-15

DATA,
CLK FROM
SYSCON IC501

G16

N

Q701

55

56

VFL

60

FL DRIVER

MSM9202-03GS

VCC

64

OSC0

C702

G

1

P

(36)

LED DRIVER

M66310FP

+5V

DIG 16

IC701

OSC1

58

59

R706

SQ. WAVE

DISPLAY BD.

IC702

P1-36

G1-15

5V p-p

FRONT
PANEL
LED’s

POWER SUPPLY (CDP-CX235)

6

1A122 1238

7/7/00

7

When the output of IC505 is LOW, these microprocessors are held in
reset and are inactive (apparently dead).

3.7Vac

A low AC voltage from power transformer T901 is applied to the filament
of the fluorescent indicator tube FL701.

-28V

The 41-ohm secondary winding of transformer T901 produces 31.7Vac
that is rectified by D505. The –40Vdc produced is regulated by Q501
using zener diode D506 for voltage stabilization.
The –28Vdc output from regulator Q501/emitter is applied to the fluores­cent driver stage as the negative supply voltage and to one end of the
filament via D507as the tube’s electron source.

Fluorescent Display

The FL701 Fluorescent Display tube needs the following to light a seg­ment or a word in the tube:

• Filament voltage

• Positive voltage simultaneously applied to the grid and plate.

Basic Operation

The filament voltage comes from the power transformer T901 and the
positive pulses come from FL Driver IC701.
Just like a vacuum tube, the fluorescent display tube needs a source of
electrons. The electrons come from the filament, which is connected to
the –28V source. A controlling grid in the middle acts as a gate to deter­mine if electrons should pass onto the plate to make it glow. At the gate,
a more positive voltage than the filament attracts the electrons and opens
the gate. A grid voltage that is the same as the filament will keep elec­trons from leaving the filament so there is no glow.
The plate structures will be phosphorescent when struck by electrons. To
get the electrons to the plate, the plate must have a positive voltage to be
attractive.

P1

Grid & Plate Array

Within the FL tube there are 16 grid structures, each containing 36 plates.
Each grid structure produces a character or number by luminating a com­bination of plates.

P3

P1
P2
P3

G1

P4
P5
P6

P1
P2
P3

G2

P4
P5
P6

Plate and Grid
Structures

To make a specific plate glow, a grid structure is selected and a positive
voltage is applied to it. At that time, the plate structures that must glow
are also brought positive. In the diagram above, when G1 and P3 lines
are brought HIGH, the P3 plate in the G1 structure will glow. Even though
the P3 structure in the G2 structure is connected in parallel, receiving the
same voltage, it will not glow because the G2 voltage is LOW at this time.
The job of FL Driver IC701 is to create and time the grid and plate pulses.

Fluorescent Driver IC701

When the CD Changer is plugged into AC, Vcc is applied to IC701/pin 64,
starting its internal oscillator. The R-C parts that set the frequency of this

2.48MHz oscillator (16MHz is on the schematic) are located at IC701/
pins 58 and 59.
Also at AC plug in, the FL Driver IC701 is momentarily reset. IC505 mo­mentarily holds its output LOW when +5V is input. This LOW resets FL
Driver IC701 when Vcc (power) is present at pin 64. The LOW lasts for

0.2ms (IC505) + 0.8ms (C507) = 10ms.

Simple FL

P2

GridFilament

Plates

Tube
Structure

L901
NOISE
FILTER
CHOKE

Ω

55

THERMAL
FUSE

MAIN BD.

T901

JACK

BD.

C502

1000

2Ω

D505

Ω

2

Ω

2

+

41

R502

D506
30V

3.7VAC
FILAMENT

VOLTAGE

R501
33k

Ω

-28V

-40V

P

Q501

D507

6.2V

IC505

PST994D
C503
100

+

IC504

REG

TA7805

+

D501-

D504

D509

R505

R508

D508

5.1V
+11.5V SOURCE TO: IC506

REGULATOR,
IC503 MOTOR DRIVER

+

+11.5V

C501

3300

-13.5V SOURCE TO: MUTE
TRANSISTORS Q325,Q327,
Q425 AND IC503 MOTOR DRIVER

C507

R506

SYSCON

IC501/30

C506

C505

+

14 2 3

15 1 1

JOG

BD.

13 3 2

115

+

7 9 9

+5V

SOURCE

(B+)

+5V TO MUTE
TRANSISTORS
Q325/E,Q327/E,
Q425/E

FL701 FL INDICATOR TUBE

1

-28V

65

R701

100k

-28V

7

RESET

+5V

+5V

2.5V p-p

OSC.2.48MHz

WORDS

GRIDS 1-15

DATA,
CLK FROM
SYSCON IC501

G16

N

Q701

55

56

VFL

60

FL DRIVER

MSM9202-03GS

VCC

64

OSC0

C702

G

1

P

(36)

LED DRIVER

M66310FP

+5V

DIG 16

IC701

OSC1

58

59

R706

SQ. WAVE

DISPLAY BD.

IC702

P1-36
G1-15

5V p-p

FRONT
PANEL
LED’s

POWER SUPPLY (CDP-CX235)

8

1A122 1238

7/7/00

9

,

,

Plug into AC

+5V

T

1

2

CH1 5.00 V=

CH2!5.00 V= MT B10.0ms- 3.16dv ch1+

Reset

10msec/div

After reset, IC701 begins normal operation, producing sequential grid
pulses first. When IC701/pin 60 goes HIGH (+5V), IC701 outputs a posi­tive going pulse at each grid pin, one after the other. Each grid pulse is
applied to a grid cluster consisting of 36 individual plate structures. After
all 16 grids are pulsed (G1 – G16), the sequence repeats. Nothing ap­pears in the display at plug-in because the fluorescent tube has not re­ceived plate voltage.
The waveform below shows grid pulses applied to G14, G15, and G16 of
the fluorescent tube.

ch1

ch2

ch3

ch2:dc =-27.3 V, rms = 28.3 V
1

pkpk= 33.8 V, freq= 304 Hz

2

3

T

CH1 20.0 V=

CH2 20.0 V=

CH3!20.0 V= CHP MTB 500us- 2.34dv ch3+

Fluorescent tube Grid pulses at Power OFF

Plate voltage pulses appear only when the CD Changer is powered ON.
At power ON, Syscon (IC501 is not shown) sends data to IC701 so it can
output these pulses. Positive pulses are output the appropriate plate pins
P1-36 to form a number, letter or word when a grid pulse is simultaneously
present.
The following waveforms show a plate signal (Ch 1) compared to the grid
16 signal (Ch 3). This plate segment is lit at the grid assembly 16 location
when both the plate and the grid outputs are HIGH.

ch1

ch3

1

3

T

CH1 20.0 V=

CH3!20.0 V= CHP MTB 500us- 2.34dv ch3+

Fluorescent tube pulses during Power ON
Chan Name Location Voltage
1 P14 IC701/pin 18 30Vp-p
3 G16 IC701/pin 55 30Vp-p
Time base = 500usec

By looking at Channel 1, we see that the plate signal also goes high at
times when grid 16 is not HIGH (Ch 3 = LOW). This means a similar plate
at a different grid is lit at this time.

Chan Name Location Voltage
1 G14 IC701/pin 53 30Vp-p
2 G15 IC701/pin 54 30Vp-p
3 G16 IC701/pin 55 30Vp-p
Time base = 500usec

L901
NOISE
FILTER
CHOKE

Ω

55

THERMAL
FUSE

MAIN BD.

T901

JACK

BD.

C502

1000

2Ω

D505

Ω

2

Ω

2

+

41

R502

D506
30V

3.7VAC
FILAMENT

VOLTAGE

R501
33k

Ω

-28V

-40V

P

Q501

D507

6.2V

IC505

PST994D
C503
100

+

IC504

REG

TA7805

+

D501-

D504

D509

R505

R508

D508

5.1V
+11.5V SOURCE TO: IC506

REGULATOR,
IC503 MOTOR DRIVER

+

+11.5V

C501

3300

-13.5V SOURCE TO: MUTE
TRANSISTORS Q325,Q327,
Q425 AND IC503 MOTOR DRIVER

C507

R506

SYSCON

IC501/30

C506

C505

+

14 2 3

15 1 1

JOG

BD.

13 3 2

115

+

7 9 9

+5V

SOURCE

(B+)

+5V TO MUTE
TRANSISTORS
Q325/E,Q327/E,
Q425/E

FL701 FL INDICATOR TUBE

1

-28V

65

R701

100k

-28V

7

RESET

+5V

+5V

2.5V p-p

OSC.2.48MHz

WORDS

GRIDS 1-15

DATA,
CLK FROM
SYSCON IC501

G16

N

Q701

55

56

VFL

60

FL DRIVER

MSM9202-03GS

VCC

64

OSC0

C702

G

1

P

(36)

LED DRIVER

M66310FP

+5V

DIG 16

IC701

OSC1

58

59

R706

SQ. WAVE

DISPLAY BD.

IC702

P1-36
G1-15

5V p-p

FRONT
PANEL
LED’s

POWER SUPPLY (CDP-CX235)

10

1A122 1238

7/7/00

11

PM3394, FLUKE & PHILIPS

,

Power On

Once the CD Changer is plugged into AC, pressing the front panel Power
button permits Syscon to enable regulator IC506. IC506 outputs D+5V,
+7V, and a reset signal to power the remaining devices on the BD board
and turn on 2 LEDs to illuminate the disc door compartment.

AC Power Only

When the CD changer was plugged into AC, Syscon IC501 received power
at pin 37 and was fully functional as marked by the X501 activity at pins
31 and 32. There is even data and clock signals leaving IC501/pins 18,
19 and 58. These signals go to FL Display Driver IC701, but there is no
instruction to turn on the front panel display while the unit is still OFF.

ch1

ch2

ch3

1

T

2

3

pin 65 to enable regulator IC506. IC506 has three outputs:

1. D+5V from pin 2 is used to:

• Power the digital ICs on the DB board; and

• Turn on the LED at the disc door compartment. This also lets the user

know the unit is ON.

2. +7V from pin 9 is used to:

• Power the focus/sled/tracking driver IC102; and

• Power the coils and motors on the BD board

3. XRST from pin 6 goes HIGH to:

• Unmute the analog audio output lines; and

• Enable Servo Control IC101 and the focus/sled/tracking driver IC102

on the BD board.

Communications IC501 – IC701

At power On, the communications activity increases between IC501 and
IC701. This is to provide constant update information to the display IC701.

ch1

ch2

ch3

1

T

2

Power ON

Syscon IC501 receives the power ON command from the front panel push
button at pin 44 (LOW). IC501 responds by outputting a HIGH at IC SW

CH1 5.00 V=

IC501 Activity at Power OFF

Channel Name CN501/pin

1. FL Data 1

2. FL CLK (Clock) 2

3. FL LT (Latch) 4

Time base = 50usec/div

3

CH1 5.00 V=

IC501 Activity at Power ON

Channel Name CN501/pin

1. FL Data 1

2. FL CLK (Clock) 2

3. FL LT (Latch) 4

Time base = 50usec/div

PUSH
BUTTONS

POWER

DISPLAY BD.

MAIN BD.

R732

CN701/602

+11.5V

+5V

2

JOG BD.

50mVp-p

X501

10MHz

4Vp-p

97

CN601/501

KEY 1

VCC

VCC

32

31

+5V

37 65

IC501

44

SYSCON

CXP84340-075Q

VCC

1

4
8

10

ICSW

IC506 LA5616

REG

EN1

EN2

REG

FL DATA

18

FL CLK

19

58

50

48

49

RESET

FL LT

DATA

CLK

XLT

DOOR
LUMINATION

C508

CN501

1

2

4

18

20

19

CN502

2

6

7

4.8V

9

+

IC701/PIN

63

62

61

5

7

6

IC101/PIN

D+5V

SOURCE

XRST TO

C509

IC101/3,

IC102/15

+5V

C511

+7V
SOURCE TO
DRIVER
IC102 (B BD.)

IC701
FL DRIVER
(DISPLAY BD.)

IC101
DSP
(BD.BD.)

TO
BD.
BOARD

POWER ON
MUTE
(MAIN BD.)
Q325,Q327,
Q425

POWER ON

12

2A122 1242

6 28 2000

Communications IC501 – IC101

PM3394, FLUKE & PHILIPS

Communications from Syscon to Servo Control IC101 does not occur
until the disc is chucked on the spindle motor and ready to play (after the
loading motor finishes chucking the disc). This communications is shown
below:

ch1

13

ch2

ch3

1

2

T

3

CH1 5.00 V=

CH2!5.00 V=

CH3!5.00 V= CHP MTB1.00ms- 3.24dv ch3-

Channel Name CN502/pin

1. Data 18

2. CLK (Clock) 20

3. XLT (Latch) 19

Time base = 1msec/div

IC501 Activity at CD Play

PUSH
BUTTONS

POWER

DISPLAY BD.

MAIN BD.

R732

CN701/602

+11.5V

+5V

2

JOG BD.

50mVp-p

X501

10MHz

4Vp-p

97

CN601/501

KEY 1

VCC

VCC

32

31

+5V

37 65

IC501

44

SYSCON

CXP84340-075Q

VCC

1

4
8

10

ICSW

IC506 LA5616

REG

EN1

EN2

REG

FL DATA

18

FL CLK

19

58

50

48

49

RESET

FL LT

DATA

CLK

XLT

DOOR
LUMINATION

C508

CN501

1

2

4

18

20

19

CN502

2

6

7

4.8V

9

+

IC701/PIN

63

62

61

5

7

6

IC101/PIN

D+5V

SOURCE

XRST TO

C509

IC101/3,

IC102/15

+5V

C511

+7V
SOURCE TO
DRIVER
IC102 (B BD.)

IC701
FL DRIVER
(DISPLAY BD.)

IC101
DSP
(BD.BD.)

TO
BD.
BOARD

POWER ON
MUTE
(MAIN BD.)
Q325,Q327,
Q425

POWER ON

14

2A122 1242

6 28 2000

15

Door Motor Drive

The sliding door in the model CDP-CX235 was an improved feature over
the previous manual trap door that the user pulled down to access the
disc tray table. The sliding door mechanism consists of a motor that
drives a series of gears to slide the door on plastic tracks. The door motor
stops turning when the limit switch is toggled in the closed or open posi­tion.

Operation

Syscon IC501 controls the door movement. Only after the CD Changer is
powered ON will IC501 respond to the OPEN/CLOSE Door button at the
Key 2 input (IC501/pin 43).

Pressing the door button causes IC501 to check the position of the door.
S810, a 3-position switch, places one of three voltages at Syscon IC501/
pin 39 to indicate the door position.

Door Position Feedback

Door Position Location Voltage
Closed CN504/pin 1 2.5V
Neutral (in-between) CN504/pin 1 5V
Open CN504/pin 1 0V
A closed door will be driven open and vice versa.

Drive

Syscon IC501 applies an output voltage to pin 23 or pin 24 to drive the
motor. The resultant positive or negative voltage is applied to the door
motor.

Door Motor Drive
Movement IC501/pin 24 IC501/pin 23 IC503/pin 9
Door Opening 4.7V 0V -3.6V
Door Closing 0V 4.8V +3.7V

Feedback

As the door moves, S810 enters the neutral position and 5V is applied to
IC501/pin 39. When the door reaches the end of travel the door toggles
the S810 limit switch to the other end. IC501/pin 39 is lowered to either

2.5 or 0V. IC501 responds by stopping the motor voltage at pin 23 or 24

S621

OPEN/

CLOSE

DOOR

+5V

CN601/501

JOG

BD.

R620

6
4

10
12

+5V

72

IC501

SYSCON

CXP84340

KEY 2

43 39

C620

73

DR

OUT

DR

IN

DOOR

SW.

24

23

R543

R552

R551

R553

8

7

(-VCC)

R554

12

-

+

CXA1291P 1/3

13 14

-13.5V

+11.5V

(VCC)

IC503

R555

1.2

9

Ω

DR-SW.

C551

R557

OUT 3

C552

R556

1.2

D OUT

R558

D IN

Ω

GND

CN504/811

CN812/810

3

4

2

1

1 2

DOOR

MOTOR BD.

M

M810

+5V

DOOR MOTOR DRIVE

16

R807

DOOR

SW BD.

OPEN

NEUTRAL

CLOSE

S810

3A122 1243

6 28 2000