Harman Kardon HD-755 Service manual
The Harman Kardon
HD755
Model HD755 silver
COMPACT DISC PLAYER
Technical Manual
Standby
CONTENTS
1. LASER BEAM SAFETY PRECAUTIONS ............. 2
2. CONTROL AND FUNCTIONS ............................. 4
3. SPECIFICATIONS AND FEATURES ..................... 7
4. AUDIO CHARACTERISTICS TEST PROCEDURE
.............................................................................. 9
5. CIRCUIT DESCRIPTION ....................................11
6. CRITICAL I.C. SPECIFICATION ........................ 15
7. PART LIST ......................................................... 41
8. TROUBLE SHOOTING GUIDE .......................... 48
* Harman/ kardon continually strives to improve its products. The HD750 Compact Disc Player design and
specifications are subject to change and may differ from the published specifications and descriptions, but will
always equal or exceed the original specifications unless otherwise stated.
9. BLOCK DIAGRAM ............................................. 54
10. SCHEMATIC DIAGRAMS .................................. 55
11. PCB LAYOUT ..................................................... 59
12. EXPLODED VIEW .............................................. 62
13. PACKING DRAWING ......................................... 63
DANGER: Invisible laser radiation when open and interlock failed or defeated.
AVOID DIRECT EXPOSURE TO BEAM.
Parts and Service Office
250 Crossways Park Dr., Woodbury, N.Y. 11797
1112-FL8350 P9603 1200 Printed in Hong Kong
LASER BEAM SAFETY PRECAUTIONS
CLASS 1 LASER PRODUCT
CAUTION
Invisible laser radiation when the unit is open.
Do not stare into beam.
CAUTION: USE OF ANY CONTROLS, ADJUSTMENT, OR
PROCEDURES OTHER THAN THOSE SPECIFIED HEREIN
MAY RESULT IN HAZARDOUS RADIATION EXPOSURE.
Do not look directly at the laser beam
coming from the pickup or allow it to
HD755
strike against your skin.
This compact disc player uses a pickup that emits a laser beam. The laser beam is emitted from the
location shown in the figure. When checking the laser diode, be sure to keep your eyes at least 1 foot away
from the pickup lens when the diode is turned on. Do not look directly at the laser beam.
CAUTION:
Using controls and adjustment, or doing procedures other than those specified herein, may result in
hazardous radiation exposure.
2
SAFETY PRECAUTIONS
WARNING
To prevent fire or shock hazard, do not
HD755
This symbol is intended to alert the user to
the presence of uninsulated "dangerous
voltage" within the product's enclosure that
may be of sufficient magnitude to constitute a risk of electric shock to persons.
This symbol is intended to alert the user to
the presence of important operating and
maintenance (servicing) instructions in the
literature accompanying the appliance.
Caution: To prevent electric shock do not use this
(polarized) plug with an extension cord, receptacle or other outlet unless the blades can be
fully inserted to prevent blade exposure.
Attention: Pour prevenir les chocs electriques ne pas
utiliser cetre fiche polarisee avec un
prolongateur, une prise de courant ou une autre sortie de courant, sauf si les lames prevent
etre inserees a fond-sans en laisser aucune
partie a decouvert.
expose the unit to rain or moisture.
HANDLING LASER PICKUP
The laser diode in the optical system of this player can be damaged by electrostatic discharge from
your clothes or your body. Proper electrostatic grounding for service personal is required during servicing.
BEFORE REPAIRING THE COMPACT DISC PLAYER
Preparation
Human Body Grounding:
Many of the components used in this compact disc player, including the laser pickup, are sensitive to
electrostatic discharge. Service personal should be grounded with an electrostatic armband (1 Mohm).
Caution:
Static charge on clothing does not escape through a body grounding wrist band.
Be careful not to contact the pickup or electrical components with your clothing.
Workbench and Tool Grounding:
A properly-grounded electroconductive plate (1Mohm) or metal sheet should be fitted to the workbench
surface. Tools and instruments (such as soldering irons and scopes) should be grounded to prevent AC
leakage.
Note: Laser diodes are so susceptible to damage from static electricity that, even if a static discharge does
not ruin a diode, it can shorten its life or cause it to work improperly.
3
Front Panel Controls
HD755
Standby
2
1
Power Switch
1
Status Mode Indicator
2
Headphones Jack
3
Headphones Level Control
4
CD Drawer
3 4
12 11
14
13
5
5
Open/Close Button
6
Search Button
7
Skip Button
8
Stop Button
9
Play/Pause Button
6
A
Repeat Button
B
HDCD Indicator
C
Information Display
D
Remote Sensor
Program Button
15
151617 9
10
87
16
17
Random Button
Repeat Button
Power: Press this switch to apply power to
the HD750. Then the Status-Mode Indicator
1
will turn green, the Information Display
C
will illuminate and all trays will be checked
automatically for discs. Press the switch again to
turn the unit off;the Status-Mode Indicator
1
will turn amber,indicating that the unit is in
Standby. When the HD750 is connected to a
switched AC outlet,such as those found on the
back of many audio products, and the AC outlet
will be turned on,the unit will turn to Standby
mode only.
1
Status-Mode Indicator: When the
HD750 is in the On mode, this indicator will
glow green. When the unit is off, the indicator
will glow amber,indicating that the unit is still
connected to AC power.
2
Headphones Jack: Connect a set of standard headphones to this jack for private listening.
Program Button: This button is used to
Program Button: This button is used to
15
program the playback of a disc in a particular
program the playback of a disc in a particular
order.
order.
Random Button: Press this button to
16
have all of the tracks played in a random order.
Repeat Button: Press this button once to
17
repeat only the tracfk currently being played. Press
it again to continually repeat all tracks on a disc.
3
Headphones Level Control: Turn this knob
to increase or decrease the volume level for
headphones connected to the HD750’s
Headphones Jack
level will not change the sound level for the
unit’s main output,as that remains constant.
4
CD Drawer: This drawer holds the discs
that will be played.Press the Open/Close button
5
to open the drawer so that discs may be
inserted.
5
Open/Close: Press this button to open or
close the disc drawer. DO NOT push the drawer
to close it or damage to the transport mechanism may result.
6
Search: Press one side of this button to
search forward
button to search backwards
disc to locate a particular portion of the disc
being played.
7
Skip: Press the right side of this button to
move to the next track
the button to move back to the previous track
‡fi
on the disc being played.
8
Stop: Press this button to stop the disc currently being played. During programming
functions, this button is also used to exit the pro-
gram mode.
2
.Note that changing this
—
or the other side of the
‚
fl·
or the left side of
through a
9
Play/Pause Button:Press this button to
start the playback of a CD.If the CD drawer is
open,pressing this button will automatically
close the drawer. When a disc is playing press
this button once to momentarily stop a disc.
When the button is pressed again, the disc will
resume play at the point it was stopped.
A
Intro Button: Press this button to put the HD750
in teh Intro Scan mode. When you press the button, the
unit will play the first 10 sec of each track on the disc, and
then move to the next track. Press the button again to
defeat the function and continue full play of the current track.
B
HDCD Indictaor: The LED will light automatically
when a CD with HDCD encoding is playing. No
further action is needed to enjoy the benefits of HDCD.
C
Information Display: This display
provides details about the operation of the
HD750.
D
Remote Sensor: The sensor behind this
window receives commands from the remote
control.Keep this area clear if you wish to use
the HD750 with a remote control.
Important Note: When the unit is turned off
(to Standby), pressing any button on the front
panel will turn the unit on. When Play 5 10
on the front or on the remote is pressed, the unit
will automatically turn on and start playing the disc
actually loaded.
4
Rear Panel Connections
4
2 3 1 5
HD755
Digital Output
Audio Outputs
Remote Control Output
Digital Output: Connect this jack to the coaxial
digital input of an external digital-to-analog
converter for direct access to the digital signals of
HD750, DO NOT connect this jack to the standard
audio inputs of any device.
Audiio Outputs: Connect these jacks to the CD
audio inputs of your receiver, surround processor or
preamplifier.
Remote Control Input
AC Power Cord
Remote Control Output: Connect this
jack to the input of another compatible Harman
Kardon remote controlled device to have the
remote sensor on the HD750 provide signals to
other products.
Remote Control Input: Connect the output of a remote infrared sensor or the remote
control output of another compatible Harman
Kardon product.This will enable the remote control system to operate even when the front panel
Remote Sensor is blocked. It will also allow
use of the HD750 with optional, external control
systems.
AC Power Cord: Connect this plug to an AC
outlet, if the outlet is switch controlled, make
certain that the switch is in the ON position.
5
Remote Control Functions
HD755
1
17
2
3
4
5
16
15
14
13
12
11
10
9
8
7
6
Display Button
1
2
Numeric Controls
3
Clear Button
4
Search Buttons
5
Skip Buttons
6
Stop Button
7
Play Button
8
Program Button
9
Pause Button
10
Check Button
11
Time Button
12
Random Button
13
Repeat Button
14
A B Button
Power On
15
16
Power Off
Open/ Close Button
17
HD755
6
HD750 Preliminary Production Specification Version 0.1
GENERAL INFORMATION
1. Power Consumption Operating <18W; Standby <5W
2. Power Super 230V AC 50Hz
3. Dimensions 440 x 130 x 386mm
4. Product Outlook Refer to attached diagram
5. Remote Unit harman/kardon remote code
6. Compliance Requirement i EMC EN55013, EN61000-3-2,
EN61000-3-3, EN55022
ii. CE (LVD EN60065)
iii. HDCD
7. Sound Processor HDCD
8. CD Servo System Digital Servo, Auto Alignment
AUDIO SPECIFICATION
HD755
Typical Limit
Output Level 1KHz 0dB (no HDCD) 1.0 Vrms +-1dB
Output Level 1KHz 0dB (HDCD output) 2.0Vrms +- 2dB
Frequency Response 20Hz~20KHz reference +0-1dB +0.5-1.5dB
THD 1KHz 0dB (30KHz Filter) 0.006% 0.01%
THD 1KHz 0dB (no any filter) 0.03% 0.08%
THD 20Hz~20KHz 0dB (30KHz Filter) 0.04% 0.05%
S/N 1KHz 0dB A-weighted (A Filter) 96dB 96dB
Dynamic Range 95dB 95dB
Channel Separation 1KHz 0dB(30KHz Filter) 94dB 90dB
Channel Balance +-0.5dB +-1.5dB
De-emphasis (5KHz,16KHz) +-0.5dB +-1.5dB
Headphone output specification under 32 ohm load
Maximum Headphone Output Level 1KHz 0dB 1.5Vp-p +-0.2V
Frequency Response (20~20KHz) +-1dB +-1.5dB
THD 20~20KHz 0dB (30KHz Filter) 0.1% 0.2%
Test Disc Specification
Typical Limit
Black Dot TCD 725B 1000um 600um
7
HD750 Preliminary Production Specification
Test Disc Specification
Typical Limit
Black Dot TCD 725B 1000um 600um
Interruption MCD-131 900um 600um
Finger print 75um 65um
Vertical Deviation MCD-151 0.92mm 0.92mm
Eccentricity TCD 712 140um 140um
8cm test disc TCD 783 Last Track Last Track
Access Time 1st to last track YEDS18 4 sec 10 sec
HD755
8
Audio Characteristics Test Procedure
Test Equipment
1. 3346 CD Player Evaluating Filter x 2 (NF Electronic Instrument)
2. VP7722 Panasonic Audio Analyzer
3. Sony YEDS18 Test CD disc
Procedure
Equipment Setup
1. The audio output of the CD player under test is connected to the CD filter L
& R inputs.
2. The outputs from the filter are connected to the Audio Analyzer.
Check the output Voltage
1. Set the mode of the filter to ‘THRU’
HD755
2. Set the mode of Audio Analyzer to ‘LEVEL’ mode
3. Select track 2 of the test disc and play the CD disc
4. The output voltage and gain of the R & L channels are taken by pressing
the respective buttons on the control board of Audio Analyzer.
Frequency Response
1. Set the mode of the filter to reference level mode.
2. Select the track 3, 4, 5, and 6 of the test disc and run it under ‘ Play’ mode.
3. Check the output of the R & L Channels
Total Harmonic Distortion
1. Set the mode of the filter to ‘DIST/CH-SP’ mode
2. Set the audio analyzer to ‘DIST’ mode.
3. Set the unit of the audio analyzer to ‘ %’ mode
4. Select the track 2, 4, and 5 on the test disc and run them under ‘ PLAY ’
mode
5. Check the % of each R & L channels
9
Signal to Noise Ratio
1. Set the mode of the filter to ‘ S/N’ mode
2. Play track 2 of the test disc
3. The unit of the audio analyzer is set to dB mode
4. Press the S/N key on the control panel of the audio analyzer
5. Play track 7
6. Measure the data of S/N ratio
Dynamic Range
1. Set the mode of the filter to ‘D-Range’ mode
2. Set the audio analyzer to ‘DIST’ Mode
3. Set the unit of the audio analyzer to ‘dB’ mode
4. Play track 17of the test disc
5. The dynamic range should be |A| + 60dB
HD755
Channel Separation
1. Set the mode of the filter to ‘DIST/CH-SP’ mode
2. Set the audio analyzer to ‘LEVEL’ mode
3. Play the tracks 8, 9, 10 & 11
4. The measured results is the difference between L & R channel
De-emphasis
1. Press the ‘THRU’ button of the CD filter
2. Play the track 2 of the test disc
3. Press the ‘Relative Level’ and make it ‘ ON’
4. Select the track 12 and 13 and measure the L & R channels value
10
FUNCTION DESCRIPTION
32312821302325
24
GCTRL
To Focus System
TBAL
Subtraction
R10
TENC8TEOUT
V
GCTRL
C2
C15C5R5
V
REF1VREF2
R15
R14
V
TBAL
Tracking System
E
A B
C D
HD755
F
PDIC
The tracking error output of E and F is given to Pin 25 (TEOUT). C8 is required for
oscillation-proof. R10 is chosen such that TEOUT of Pin 25 become 1.4Vp-p.
During alignment procedure, the DSP IC (MN662790) will adjust the tracking balance
voltage V
from Pin 31. V
TBAL
varies with reference to the center voltage V
TBAL
(=1.65 V)
REF2
within ±0.5 V.
The tracking gain will change according to the type of disc. For normal disc or CDR disc,
V
is set to V
GCTRL
; for CDRW disc V
REF2
focus gain is changed too.
is set to V
GCTRL
11
- 0.75 V. At the same time, the
REF2
Focus System
3634282927
26
GCTRL
FBAL
Subtraction
R7
FENC4FEOUT
V
GCTRL
C2C3R6
V
FBAL
35333
5
C35
C47
R27
R21
R20
E
A B
C D
F
HD755
PDIC
The focus error output of A, B, C and D are given to Pin 27. C4 is required for oscillationproof. R7 is set such that FEOUT of Pin 27 becomes 1.46 Vp-p.
During alignment procedure, the DSP IC (MN662790) will adjust the focus balance voltage
V
from Pin 30. V
FBAL
varies with reference to the center voltage V
FBAL
(=1.65 V) within
REF2
±0.5 V.
The focus gain will change according to the type of disc. For normal disc or CDR disc,
V
is set to V
GCTRL
; for CDRW disc V
REF2
is set to V
GCTRL
- 0.75 V. At the same time, the
REF2
tracking gain is changed too.
12
RF, EQ, AGC
36
34
GCTRL
V
GCTRL
C2
35333
5
C35
C47
R27
R21
R206EQ
AGC
8910
17
RF
ENV
11
12
V
CC1
ARF
V
CC1
NRFDET
ENV
28
C29
C39
C28
C38
RFOUT
HD755
DETECTION
DETECTION
The signals A, B, C and D input from PDIC are composed into the RF signal by the RF
Addition Amp, then output from RFOUT of Pin 5. This Amp is designed so that RFOUT is
about 0.5 Vp-p for normal CD disc (about 0.4 Vp-p for CDR and 0.12 Vp-p for CDRW).
RF signal from Pin 5 is then input to the AGC block through the EQ block (the EQ
characteristic is fixed for single speed operation in this design). It is then gain-controlled
and output to Pin 10 ARF. The AGC block maintains the output level of ARF to about
1.0Vp-p for all types of disc. C38 connected to Pin 9 is for the AGC loop filter.
The RF Detection block detects the amplitude of the RF signal inputted from the EQ block.
Inputted RF signal is detected after passing through a high-pass filter. Detection level is
changed in accrodance with the voltage of GCTRL Pin 28.
The ENV detection block detects the fluctuation of the 3T-composition in the RF signal
which is needed for focus balance adjustment. C39 connected to Pin 11 forms a filter for
detecting the signal fluctuation. The ENV output signal from Pin 12 is filtered by C29.
13
19LD2
1
V
CC1
PD
170mV
LASER UNIT
C33
R18Q1LDON
20
R
V
CC1
R
R/2
V
REF1
22
R
V
CC2
R
R/2
V
REF2
HD755
APC
The laser diode has large negative temperature characteristic in its optical output when
driven with a constant current on laser diode. Therefore, the output on processing monitor
photo diode, must be a controlled current for getting regular output power, thus the APC
(Auto Power Control) circuit is composed.
Reference Power Supply
A reference power supply for servo is built-in. The current capacity of the reference supply
is about 3 mA.
V
REF1
= 1/2 V
= 2.5 V
CC1
V
= 1/2 V
REF2
where V
= 1.65 V
CC2
= 5 V and V
CC1
= 3.3 V
CC2
14
MN662790RSA1
Signal Processing LSI for CD Players
Overview
The MN662790RSA is a CD signal processing LSI that,
on a single chip, combines optics servos for the CD player
(focus, tracking, and traverse servos), digital signal
processing (EFM demodulation and error correction),
digital servo processing for the spindle motor, digital
filter, and D/A converter, so thus covers all signal
processing functions from the head's RF amplifier onward.
Features
(Optics servo)
Focus, tracking, and traverse servos
Automatic adjustment functions for FO/TR gain,
FO/TR offset, and FO/TR balance
Built-in D/A converter for drive voltage output
Built-in dropout countermeasures
Anti-shock functions
Built-in track cross counter Digital input pins
Traverse speed detection function
(Digital Signal Processing)
Built-in DSL and PLL
Frame synchronization detection, holding, and
insertion
Subcode data processing
Subcode Q data CRC check
Built-in subcode Q data register
CIRC error detection and correction
C1 decoder: duplex error correction
C2 decoder: triplex error correction
Built-in 16-K bits of RAM for use in de-
interleaving
Audio data interpolation
Averaging or retention of previous values
Digital attenuation (–12 dB)
Audio data peak level detection function
Digital audio interface (EIAJ format)
Audio data serial interface for input and output
(Audio circuits)
Digital filter using 8-fold oversampling
Built-in D/A converter (1-bit D/A converter)
Built-in differential operational amplifier (secondary
low pass filter)
(Other)
Built-in playback pitch control function (normal
speed only) (±13%)
Support for quadruple-speed playback (digital servo
and signal processing block only)
Built-in support for jitter-free disc rotation synchronization playback
Oscillator shutdown mode
Power management mode
Operating voltage 3.3 V for internal circuit; 5 V for
Applications
CD players
HD755
(Spindle Motor Servo)
CLV digital servo
Switchable servo gain
15
MN662790RAS1
Pin Assignment
HD755
BYTCK/TVSTOP
CLDCK
FCLK
IPFLAG
FLAG
CLVS
CRC
DEMPH
FLAG6/RESY
IOSEL
TEST
AV
DD1
OUTL
AV
SS1
OUTR
RSEL
CSEL
PSEL
MSEL
SSEL
SS2AVDD2
VDDX2X1VSSSBCK
60595857565554535251504948474645444342
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
12345678910111213141516171819
BCLK
LRCK
SS1
DD1
DV
DV
SRDATA
SUBC
VCOF2
TX
MCLK
PCK
EFM
AV
MLD
SENSE
MDATA
VCOF
PLLF
FLOCK
TLOCK
BLKCK
DSLF
SQCK
REF
DRF
I
SUBQ
DMUTE
ARF
WVEL
RST
STAT
PLAY
PLLF2
41
20
SMCK
PMCK
40
LDON
39
BDO
38
RFDET
37
TRCRS
36
OFT
35
VDET
34
RFENV
33
TE
32
FE
31
TBAL
30
FBAL
29
V
28
27
26
25
24
23
22
21
REF
FOD
TRD
KICK
ECS
ECM
PC
TVD
TRV
(TOP VIEW)
QFS080-P-1414
16
MN662790RAS1
Block Diagram
51
AV
SS2
50
AV
DD2
LRCKIN/MSEL
BCLKIN/SSEL
SRDATEIN/PSEL
70
IOSEL
66
CLVS
67
CRC
SBCK
SUBC
SSEL
SQCK
SUBQ
PCK
EFM
PLLF
PLLF2
DSLF
I
REF
DRF
ARF
RSEL
PSEL
MLD
MCLK
VCOF
SMCK
FCLK
PMCK
CSEL
MSEL
X2
X1
STAT
13
62
56
55
68
69
80
14
15
53
52
48
41
47
45
46
44
76
78
9
7
8
54
49
19
63
20
77
79
59
58
17
BLKCK
CLDCK
DEMPH
FLAG6/RESY
MDATA
CK384/EFM
VCOF2
DIGITAL
DEEMPHASIS
BUFFER
SUBCODE
DSL•PLL VCO
EFM DEMODULATION
SYNC INTERPOLATION
8 TIMES
OVER SAMPLING
DIGITAL FILTER
SUBCODE DEMODULATION
LOGICS
1 BIT DAC
16K
SRAM
CIRC ERROR CORRECTION
DEINTERLEAVE
VCO
INTERFACE
MICROCOMPUTER
TIMING
GENERATOR
PITCH CONTROL
A/D CONVERTER INPUT PORT
)
R
(
PWM
)
L
(
PWM
DIGITAL
AUDIO
CLV
INTERPOLATION
SOFT MUTING
DIGITAL
SERVO CPU
SERVO
TIMING GENERATOR
–
+
–
+
INTERFACE
SERVO
ATTENUATION
PEAK DETECT
AUTO CUE
D/A
OUTPUT
75
73
74
72
65
64
6
24
23
2
3
1
16
21
26
29
61
25
22
27
28
31
CONVERTER
30
12
11
42
40
PORT
43
10
OUTR
OUTL
AV
SS1
AV
DD1
FLAG
IPFLAG
TX
ECM
PC
LRCK
SRDATA
BCLK
DMUTE
TRV
KICK
V
REF
BYTCK/TRVSTOP
ECS
TVD
TRD
FOD
TBAL
FBAL
TLOCK
FLOCK
PLAY
LDON
WVEL
SENSE
HD755
605745187132
SS
DD
V
SS1
DD1
V
DV
DV
RST
TEST
FE
33TE34
RFENV
37
TRCRS
17
35
VDET
39
BDO
38
RFDET
36
OFT
MN662790RAS1
Pin Descriptions
Pin No. Symbol I/O Function Description
1 BCLK O SRDATA bit clock output.
2 LRCK O Left/right channel discrimination signal output.
3 SRDATA O Serial data output.
4DV
5DV
6 TX O Digital audio interface output signal.
7 MCLK I Microcomputer command clock input. (Data is latched at rising edge.)
8 MDATA I Microcomputer command data input.
9 MLD I Microcomputer command load signal input. "L" level: load.
10 SENSE O Sense signal output. (OFT, FESL, NACEND, NAJEND, SFG, and NWTEND)
11 FLOCK O During default operation, focus servo convergence signal.
12 TLOCK O During default operation, tracking servo convergence signal. "L" level:
13 BLKCK O Subcode block clock signal (f
14 SQCK I External clock input for subcode Q register
15 SUBQ O Subcode Q data output
16 DMUTE I Muting input. (Effective only for an output bit rate of 64 fs) "H" level: muting.
17 STAT O Status signal.
18 RST I Reset input. "L" level: reset.
19 SMCK O If MSEL is "H" level, 8.4672 MHz clock signal output.
20 CSEL O Oscillation frequency selection: "H" is 33.8688MHz; "L" is 16.9344MHz.
21 TRV O Traverse forced feed output. (tristate)
22 TVD O Traverse drive output.
23 PC O Spindle motor ON signal. "L" level: ON (default).
24 ECM O Spindle motor drive signal (forced mode output). (tristate)
25 ECS O Spindle motor drive signal (servo error signal output). (tristate)
26 KICK O Kick pulse output. (tristate)
27 TRD O Tracking drive output.
28 FOD O Focus drive output.
29 V
30 FBAL O Focus balance adjustment output.
31 TBAL O Tracking balance adjustment output.
32 FE I Focus error signal input. (analog input)
DD1
SS1
"L" level: convergence.
convergence.
REF
I Power supply for digital circuits.
I Ground for digital circuits.
During command execution, direction detection output for external track
counter.
During command execution, traverse speed control output.
=75 Hz)
BLKCK
(CRC, CLVS, TTSTOP, JCLVS, SQOK, FLAG6, SENSE, FLOCK,
TLOCK, rpm data, and FCLV)
If MSEL is "L" level, 4.2336 MHz clock signal output
I Reference voltage for DA output (TVD, ECS, TRD, FOD, FBAL, and
TBAL).
HD755
18
MN662790RAS1
Pin Descriptions (continued)
Pin No. Symbol I/O Function Description
33 TE I Tracking error signal input. (analog input)
34 RFENV I RF envelope signal input. (analog input)
35 VDET I Vibration detection signal input. "H" level: vibration detected.
36 OFT I Offtrack signal input. "H" level: offtrack.
37 TRCRS I Track cross signal input. (analog input)
38 RFDET I RF detection signal input. "L" level: detected.
39 BDO I Dropout signal input. "H" level: dropout.
40 LDON O Laser ON signal output. "H" level: ON.
41 PLLF2 I/O PLL loop filter characteristic selection pin.
42 TOFS O Tracking offset adjustment or DSL balance output(D/A output).
43 WVEL O Double-speed status signal output. "H" level: double-speed.
44 ARF I RF signal input.
45 I
REF
46 DRF I DSL bias pin.
47 DSLF I/O DSL loop filter pin.
48 PLLF I/O PLL loop filter pin.
49 VCOF I/O VCO loop filter pin.
50 AV
51 AV
DD2
SS2
52 EFM O EFM signal output. EFM output when IOSEL is "H" level.
or CK384 •Crystal oscillator 16.9344-MHz clock output when I
53 PCK O PLL derived clock or DSL balance output. f
54 VCOF2 I/O VCO loop filter pin.
55 SUBC O Subcode serial output.
56 SBCK I Serial clock input for subcode serial output.
57 V
SS
58 X1 I Crystal oscillator circuit input/output pins. f=16.9344 MHz, 33.8688 MHz.
59 X2 O Crystal oscillator circuit output/output pins. f=16.9344 MHz, 33.8688 MHz.
60 V
61
DD
BYTCK or
TRVSTOP When IOSEL is "L" level, traverse stop signal output. "H" level: stop mode.
62 CLDCK O Subcode frame clock signal output pin. (f
63 FCLK O Crystal frame clock signal output. (f
64 IPFLAG O Interpolation flag signal output. "H" level: interpolation.
65 FLAG O Flag signal output.
I Reference current input pin.
I Power supply for analog circuits (DSL, PLL, D/A converter output, and A/D
converter).
I Ground for analog circuits (DSL, PLL, D/A converter output, and A/D
converter).
•OSEL is "L" level.
output from signal processing block. (During
•384 f
s
variable-pitch operation, this is the VCO clock.)
Commands permit switching among the above three outputs.
=4.3218 MHz.
PCK
or DSLB
I Ground for oscillator circuit.
I Oscillator circuit power supply.
O
When IOSEL is "H" level, byte clock signal output.
=7.35 kHz)
CLDCK
=7.35 kHz)
FCLK
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MN662790RAS1
Pin Descriptions (continued)
Pin No. Symbol I/O Function Description
66 CLVS O Spindle servo phase synchronization signal output. "H" level: CLV. "L"
level: rough servo.
67 CRC O During default operation, subcode CRC check result output. "H" level: OK.
"L" level: no good.
During command execution, pulse output for external track counter.
68 DEMPH O De-emphasis detection signal output. "H" level: ON.
69 FLAG6 or O When IOSEL is "L" level, FLAG6 output, signal for resetting address of
RESY RAM for error correction de-interleave. "L" level: address reset.
When IOSEL is "H" level, RESY output, frame resynchronization signal.
"H" level: synchronized. "L" level: out of sync.
70 IOSEL I Mode selection pin
71 TEST I Test pin. Keep this at "H" level.
72 AV
73 OUTL O Left channel audio output.
74 AV
75 OUTR O Right channel audio output.
76 RSEL I RF signal polarity selection pin. "H" level: bright level is "H."
77 V
78 PSEL I When IOSEL is "H" level, test pin. Keep this at "L" level.
79 MSEL I When IOSEL is "H" level, frequency selection pin for SMCK pin output.
80 SSEL I When IOSEL is "H" level, SUBQ pin output mode selection pin.
DD1
SS1
CC5V
I Power supply for analog circuits. (common use for left and right channel
audio outputs.)
I Ground for analog circuits. (common use for left and right channel audio
outputs.)
"L" level: bright level is "L."
I 5-V power supply applied to pins for 5-V input.
When IOSEL is "L" level, SRDATA input.
"H" level: SMCK=8.4672 MHz
When IOSEL is "L" level, LRCK input.
"H" level: left channel data.
"L" level: right channel data.
SMCK output fixed at 4.2336 MHz.
"H" level: buffered subcode Q mode.
"L" level: CLDCK synchronization mode.
When IOSEL is "L" level, BCKL input.
Buffered subcode Q mode.
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