Kenwood DMCK-3 Service manual

PORTABLE MD PLAYER

System ........................... Mini disc digital audio system

Read method ................. Noncontact optical reading system (semicon-

ductor laser)

Sampling frequency ...... 44.1 kHz

Audio compression ....... ATRAC (Adaptive Transform Acoustic Coding)

Number of channels ...... 2 channels

Frequency response ...... 20 Hz to 20,000 Hz (± 3 dB)

Wow & flutter ................ Less than unmeasurable limit (± 0.001 %

W.PEAK)

Input/Output terminal .. Remote control/Phones jack

Rated power output ...... 9 mW+9 mW

Power source

DC IN jack (4–5.1V)

: Specially provided AC adaptor

: Car battery adaptor (sold separately, DC-C70)
DC 1.5V : Commercially sold AA alkaline battery (LR-6) × 1
DC 1.2V : Specially provided rechargeable battery (NB-150) × 1

(Charging time : About 3 hours)

Battery life (Fully charge, with “PS on” setting ON)

Specially provided rechargeable battery (NB-150) × 1......... Approx. 7 hours

Commercially sold AA alkaline battery (LR-6) × 1 ............... Approx. 8 hours

÷ At 0.5mW+0.5mW output (32 Ω load ).
÷ Standard value during continuous use/charging in an temperature of

25˚C.

÷ Time of use may vary depending on battery maker, battery type, use

environment, and temperatute.

÷ Time will be shorter when “PS off” Mode is set.

Dimensions (not including protruding parts)

W :99 mm (3-7/8”)
H :17 mm (11/16”)
D :75 mm (2-15/16”)

Weight (Net)............ 115g (0.25 lb)

not including the accessory rechargeable batter
140g (0.31 lb)
including the accessory rechargeable battery

1. KENWOOD follows a policy of continuous advancements in development.

For reason specifications may be changed without notice.

2.The full performance may not be exhibited in an extremely cold location (under a water-freezing temperature).

Notes

Notes

DMC-K3

SERVICE MANUAL

© 1999-1/B51-5503-00 (K/K) 2837

Lid assy
(A53-2123-03)

Escutcheon
(B07-2443-01)

Dressing panel
(A21-3741-04)

BATTERY ( L6 .R6 .AA .AM3 ) 1 . 5V

NI - MH BATTERY 1 . 2V

IN

Knob
(K29-7477-04)

Battery cover
(A09-1118-03)

OPEN

Knob
(K29-7475-03)

– VOLUME +

KENWOOD CORPORATION MADE IN JAPAN

Knob
(K29-7476-03)

Knob
(K29-7478-04)

HOLD

OPEN

Metallic cabinet assy
(A01-3664-03)

SPECIFICATIONS

DC IN 4 - 5. 1V

DC jack
(E03-0357-05)

PHONES

Miniature phone jack
(E11-0381-05)

Illustration is DMC-K3(S).

In compliance with Federal Regulations, following are reproduc­tions of labels on, or inside the product relating to laser product
safety.

KENWOOD-Corp. certifies this equipment conforms to DHHS
Regulations No. 21 CFR 1040. 10, Chapter 1, Subchapter J.

DANGER : Laser radiation when open and interlock defeated.
AVOID DIRECT EXPOSURE TO BEAM.

DMC-K3

Action

÷ Insert a MD into the unit.
÷ Replace the disc with a

prerecorded MD when
playing it back.

÷ Replace the MD.
÷ Replace the MD.

Symptom Cause Remedy

÷ The disc holder is not securely

closed.

÷ The battery is depleted.
÷ HOLD status is engaged.
÷ The volume is at minimum

level.

÷ The remote control or head-

phones are disconnected.

÷ HOLD status is engaged.
÷ The battery is depleted.
÷ The remote control or head-

phone plug is not securely in­serted.

÷ The disc holder is not securely

closed.

÷ The disc is scratched or dam-

aged or the recording is not
good.

÷ The unit is in a place where

there is excessive vibration.

÷ You are using commercial re-

chargeable battery.

÷ The unit has become hot be-

cause of exposure to direct
sunlight etc.

÷ You are using another AC

adaptor than the accessory
adaptor.

÷ The AC adaptors has become

disconnected.

Unit fails to
turn ON.

÷ Close disc holder securely.
÷ Charge the battery.

÷ Deactivate HOLD status.
÷ Increase the volume.

÷ Insert plug securely.
÷ Deactivate HOLD status.

÷ Charge the battery.
÷ Insert plug securely.

÷ Close disc holder securely.
÷ Replace the MD.

÷ Move the unit to a place

where there is little vibra­tion or set to “PS off”.

÷ Use the special recharge-

able battery (NB-150)

÷ Wait until the unit has

cooled to normal tempera­ture.

÷ Use the accessory AC

adaptor.

÷ Connect the AC adaptor

securely.

There is no
sound.

The unit does
not respond
to key opera­tion.

Sound skips.

Troubleshooting

Message Meaning

÷ There is no MD in the unit.
÷ Nothing is recorded on this

MD.

÷ The *UTOC contents are

faulty.

÷ The disc is scratched or dam-

aged, so playback is not pos­sible.

“BLANK ”

“noDISC”

“ERROR ”

Meaning of display messages

*UTOC: A recordable MD has an area for recording so-called UTOC

(User's Table of Contents) data. The UTOC contains number
of tracks, playing time, written data, and other rewritable
information.

Battery does
not charge.

Resetting the unit

This system uses a microcomputer so it may malfunction due to external
noise or interference. In such a case, unplug the power cord and remove the
batteries, then plug the power cord again and insert the batteries again.

CONTENTS / ACCESSORIES

Contents

SPECIFICATIONS.........................................Top cover

CONTENTS / ACCESSORIES ....................................2

CONTROLS.................................................................3

DISASSEMBLY FOR REPAIR.....................................4

CIRCUIT DESCRIPTION.............................................5

Accessories

PC BOARD ..................................................................9

SCHEMATIC DIAGRAM............................................11

EXPLODED VIEW .....................................................15

PARTS LIST...............................................................17

AC adapter (1) *
(W09-)

Remotcon (1)
(A70-1258-05)

Caution

Beware of condensation

When water vapor comes into contact with the surface of cold materi­al, water drops are produced.
If condensation occurs, correct operation may not be possible, or the
unit may not function correctly.
This is not a malfunction, however, and the unit should be dried.
(To do this, turn the POWER switch ON and leave the unit as it is for
several hours.)

Be especially careful in the following conditions:

• When the unit is brought from a cold place to warm place, and there is
a large temperature difference.

• When a heater starts operating.

• When the unit is brought from an air-conditioned place to a place of
high temperature with high humidity.

• When there is a large difference between the internal temperature of
the unit and the ambient temperature, or in conditions where conden­sation occurs easily.

Batteries : NB150 (1)
(W09-1267-05)

Stereo headphone (1) *
(W01-)

Carrying case (1)
(W01-0938-05)

Stereo headphone (1) *
(W01-0963-05)

* Refer to parts list on page 17.

2

CONTROLS

HOLD switch

6 (Play/pause) key

5 (Volume up) key

4 (Skip down) key

HOLD indicator

Main Unit

Play indicator

Track number indicator

Battery
indicator

7 (Stop/off) key

Charge key

LCD

DC IN jack
(Extemal power jack)

Battery cover

∞ (Volume down) key

OPEN slider

¢ (Skip up) key

PHONES jack

Disc Holder

Using the Clip

÷ Clip the remote control unit to the

edge of your bag or pocket.

Remote Control

Clip

Press and release.

PHONES jack

Hand strap
attaching hole

¢ (Skip up) key

4 (Skip down) key

MODE key

LCD

6 (Play/pause) key

7 (Stop/off) key

Charge key

HOLD switch

+ (Volume up) key

– (Volume down) key

The mode changes each time the
MODE key is pressed.

The mode changes each time the
MODE key is pressed.

MODE key

(Only by remote control operation)

1 Fast forward/fast reverse

(search)

2 Changing the display mode
3 Play Mode
4 Changing the tone

(BASS BOOST)

5 Original display

1 AUTO PLAY
2 AUTO POWER SAVE
3 Operating tone (Beep)
4 Original display

Use this key to set playback-related features and other convenient
functions. Please also read “Playback (Application)” and “Convenient
functions” for details.

When the MODE key is held de­pressed for more than 2 seconds:

÷ To change one of the above set-

ups after returning to the original
display, restart from the step of
pressing and holding the MODE
key for more than 2 seconds.

DMC-K3

HOLD

BATTERY ( L6 .R6 .AA .AM3 ) 1 . 5V

NI - MH BATTERY 1 . 2V

IN

OPEN

HOLD

OPEN

DC IN 4 - 5. 1V

PHONES

– VOLUME +

KENWOOD CORPORATION MADE IN JAPAN

E

D

O

^

M

HOLD

3

DMC-K3

1

1

1

1

2

1

1

1

3

3

7

3

3

6

5

4

x2

x2

S1

DISASSEMBLY FOR REPAIR

How to Remove Case

1. Remove 7 screws(1).

2. Slide the case to the opposite side of the battery case(2).

How to Check PCB

3. Rmove 7 screws(3x5,4x2) and unsolder the corner of pcb(5).

4. Connect the ground wire to the LCD mounting hardware and the frame of the unit(6).

5. Fix the switch 1 (ON mode) by the tape(7). And check the unit with standing it.

4

CIRCUIT DESCRIPTION

IC9

IC7

RE/SERVO

CXA2523AR

DSP/ATRAC

CXD2655BR

SERIAL XLAT XRST FOK SQSY SENS

Q6

BEEP MIXER

IC5 Q17

XSTBY BEEP

BASS BOOST

BassBoost

IC12 SEIN MUTE SW

IC8

u-COM

HEAD PHONES AMP

MOTOR DRIVER S1-S3

uPD784036GC

PSW

LA4801V

BD6601KVT

EPDO
EPDI

IC10

BEMFU,V,W

EPCS E2PROM
EPSK

AK93C45AV

ED1 com

LCD(SET)

SP PWS CHG1 CHG2 ADP CHGOK BATT

POWER SUPPLY CONTROL/RECHARGEABLE CIRCUIT

1. Main microprocessor : uPD784036GC831 (X33 : IC5)

1-1 Microprocessor periphery block diagram(X33)

DMC-K3

1-2 Pin description

Pin No. Name I/O

1 XLAT O DSP IC (CXD2655BR) LATCH signal
2 XRST O DSP IC (CXD2655BR) HARD RESET signal
3 XSTBY O RF/SERVO IC (CXA2523AR) STAND BY signal
4 LDON O PICK UP LASER on/off signal L: LIGHTING H: NON LIGHTING
5 BEEP O BEEP output/ to HP AMP
6 BASS BOOST O Analog bass boost control L: BOOST ON H: BOOST OFF
7 RESET – µ-com RESET
8 VDD – µ-com +power supply

9 X2 O µ-com SYSTEM CLOCK OSC port (out)
10 X1 I µ-com SYSTEM CLOCK OSC port (in)
11 VSS – µ-com GND
12 LCD DATA O LCD remocon display data serial output
13 BEMFW I SLED MOTOR comparator signal(W)
14 BEMFV I SLED MOTOR comparator signal(V)
15 BEMFU I SLED MOTOR comparator signal(U)

16~18 S1~3 O

SLED MOTOR control signal
for DRIVER input port

19 NC O –

Function H/L

SEG1-19

Description

5

DMC-K3

CIRCUIT DESCRIPTION

Pin No. Name I/O

SYSTEM POWER port

20 SP O

21 CHG1 O Rechargeable circuit control signal H: RECHARGEABLE

22 CHG2 O Rechargeable circuit control signal H: RECHARGEABLE

23,24 TEST0,1 I Test mode setting

25~43 SEG19~1 O Set's LCD segment output 19~1

44 NC O –
45 VSS – µ-com GND
46 TEST – µ-com TEST port (CONNECT GND)
47 COM O Set's LCD COMMON
48 EPSK O E2PROM CLOCK output

49 PW SW O
50 MUTE SW O HP amp mute control L: MUTE ON H:MUTE OFF

51 PWS O DRAM/LCD remocon power supply port H: ON L:OFF
52 EPCS O E2PROM LATCH signal
53 EPDI O E2PROM DATA signal
54 EPDO I E2PROM DATA signal
55 VDD – µ-com +power supply
56 KEY0 I Set's key input TAKE IN A/D
57 KEY1 I LCD remocon key input TAKE IN A/D
58 ADP I Adaptor DC detector TAKE IN A/D
59 CHGOK I Rechargeable battery detector TAKE IN A/D
60 BATT I Battery DC input TAKE IN A/D
61 SEIN(REVERSE) I SLED ERROR signal (REVERSE) TAKE IN A/D
62 SEIN(FORWARD) I SLED ERROR signal (FORWARD) TAKE IN A/D
63 ADON O AVREF voltage output
64 AVDD – µ-com A/D power supply
65 AVREF1 – µ-com A/D reference voltage input

66 AVSS – µ-com A/D GND
67,68 NC O –
69,70 AVREF2,3 – µ-com D/A reference voltage input

71 JTYPE I – H: EXCEPT JAPAN L:JAPAN

72 HOLD I HOLD SW

73 XINT I

74 SQSY I

75 LID SW I LID OPEN SW H: CLOSE L:OPEN

76 SCLK O DSP IC (CXD2655BR) SERIAL CLOCK input

77 W.UP I

78 SENS I DSP IC (CXD2655BR) SENSE signal

79 SRDT I DSP IC (CXD2655BR) SERIAL DATA signal

80 SWDT O DSP IC (CXD2655BR) SERIAL DATA signal

DSP IC (CXD2655BR) H: ON
RF/SERVO IC (CXA2523AR) L: OFF
Motor Driver/HP amp VCC2 power supply

(SET UP POWER SUPPLY) L: NORMAL

(START RECHARGEABLE) L: NORMAL

HP amp power supply H: ON
(CONNECT HP. AMP POWER SUPPLY PORT) L: OFF

DSP IC (CXD2655BR) H:
XINT EDGE intercept input L: óEDGE INTERCEPT

DSP IC (CXD2655BR) H:
ADIP SYNC intercept input L: óEDGE INTERCEPT

µ-com WAKU UP input H:
EDGE intercept L: óEDGE INTERCEPT

Function H/L

Description

TEST1/0
HH: TEST1
HL: TEST2/3
LH: TEST4

6