Sony MCC3000MT User manual

3D HD VIDEO CAMERA
MCC-3000MT
SERVICE MANUAL
1st Edition

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WARNING
This manual is intended for qualified service personnel only.
To reduce the risk of electric shock, fire or injury, do not perform any servicing other than that
contained in the operating instructions unless you are qualified to do so. Refer all servicing to
qualified service personnel.
WARNUNG
Die Anleitung ist nur für qualifiziertes Fachpersonal bestimmt.
Alle Wartungsarbeiten dürfen nur von qualifiziertem Fachpersonal ausgeführt werden. Um die
Gefahr eines elektrischen Schlages, Feuergefahr und Verletzungen zu vermeiden, sind bei
Wartungsarbeiten strikt die Angaben in der Anleitung zu befolgen. Andere als die angegeben
Wartungsarbeiten dürfen nur von Personen ausgeführt werden, die eine spezielle Befähigung
dazu besitzen.
AVERTISSEMENT
Ce manual est destiné uniquement aux personnes compétentes en charge de l’entretien. Afin
de réduire les risques de décharge électrique, d’incendie ou de blessure n’effectuer que les
réparations indiquées dans le mode d’emploi à moins d’être qualifié pour en effectuer d’autres.
Pour toute réparation faire appel à une personne compétente uniquement.
MCC-3000MT

Table of Contents
Manual Structure
Purpose of this manual....................................................................................................................5
Related manuals...........................................................................................................................5
Schematic diagrams, board layouts and spare parts......................................................................................5
1. Service Overview
1-1. Power Supply..................................................................................................................1-1
1-1-1. Power Specifications ...................................................................................................1-1
1-1-2. DC Power Cable........................................................................................................1-1
1-2. Installation Space..............................................................................................................1-2
1-2-1. CCU (Camera Control Unit)............................................................................................1-2
1-2-2. CHU (Camera Head Unit)..............................................................................................1-3
1-2-3. Tripod Adaptor (Supplied Accessories)................................................................................1-3
1-3. Board Location................................................................................................................1-4
1-4. External Connectors...........................................................................................................1-5
1-4-1. Signal Inputs and Outputs..............................................................................................1-5
1-5. Functions of Onboard Switches...............................................................................................1-6
1-5-1. AVP-18 Board..........................................................................................................1-6
1-5-2. DPR-340 Board.........................................................................................................1-7
1-6. Circuit Description............................................................................................................1-8
1-6-1. CMOS Block System...................................................................................................1-8
1-6-2. CHU-CCU Transmission Block........................................................................................1-8
1-6-3. Camera Block System..................................................................................................1-8
1-6-4. Video Signal System...................................................................................................1-9
1-6-5. System Control.........................................................................................................1-9
1-6-6. SDI System............................................................................................................1-10
1-6-7. Power System.........................................................................................................1-10
1-7. Service Tools/Measuring Equipment List...................................................................................1-13
1-7-1. Service Tools..........................................................................................................1-13
1-7-2. Measuring Equipment.................................................................................................1-13
1-8. Updating the Firmware......................................................................................................1-14
1-9. Writing/Rewriting PLD Data................................................................................................1-16
1-10. List of Error Numbers on the Display (Output)..............................................................................1-18
1-11. Note on Service..............................................................................................................1-19
1-11-1. Requirements on Replacement of Boards or Parts....................................................................1-19
1-11-2. Description of Number Seal on the Prism.............................................................................1-19
1-11-3. Fuse and IC Link Replacement........................................................................................1-19
1-11-4. Circuit Protection Element............................................................................................1-19
1-11-5. Lead-free Solder.......................................................................................................1-20
1-11-6. Disconnecting/Connecting Flexible Card Wire.......................................................................1-20
1-11-7. Disconnecting/Connecting Fine-Wire Coaxial Cable.................................................................1-21
1-11-8. Connecting/Disconnecting Coaxial Cable............................................................................1-22
2. Replacement of Main Parts
2-1. General Information for Parts Replacement..................................................................................2-1
2-1-1. Index....................................................................................................................2-1
MCC-3000MT 1

2-1-2. Basic Knowledge.......................................................................................................2-3
2-2. Top Cover.....................................................................................................................2-4
2-3. KY-687 Board.................................................................................................................2-5
2-4. LCD Module..................................................................................................................2-7
2-5. CN-3571 Board................................................................................................................2-8
2-6. Main Board Assembly (for CAMERA A)....................................................................................2-9
2-7. Main Board Assembly (for CAMERA B)...................................................................................2-11
2-8. DPR-340 Board..............................................................................................................2-13
2-9. AVP-18 Board...............................................................................................................2-15
2-10. CN-3550 Board..............................................................................................................2-17
2-11. CN-3549 Board..............................................................................................................2-18
2-12. RE-309 Board................................................................................................................2-19
2-13. PS-772 Board................................................................................................................2-21
2-14. Rear Panel Assembly........................................................................................................2-24
2-15. TR-150 Board................................................................................................................2-26
2-16. CN-3534 Board..............................................................................................................2-27
3. Service Menu
3-1. Overview......................................................................................................................3-1
3-1-1. Service Menu Structure.................................................................................................3-1
3-1-2. Preparation..............................................................................................................3-1
3-1-3. Basic Menu Operations.................................................................................................3-1
3-1-4. Displaying the Service Menu...........................................................................................3-1
3-2. Service Menu List.............................................................................................................3-2
3-2-1. MAINTENANCE Menu List...........................................................................................3-2
3-2-2. RPN CORRECT Menu List............................................................................................3-2
3-2-3. INFORMATION Menu List............................................................................................3-3
3-3. MAINTENANCE Menu......................................................................................................3-4
3-4. RPN CORRECT Menu........................................................................................................3-5
3-4-1. Executing Auto Detection..............................................................................................3-5
3-4-2. Correction Mode Settings..............................................................................................3-5
3-4-3. Channel Setting.........................................................................................................3-6
3-4-4. Cursor Setting...........................................................................................................3-6
3-4-5. Cursor H Position Setting...............................................................................................3-6
3-4-6. Cursor V Position Setting...............................................................................................3-6
3-4-7. Operating Cursor Next..................................................................................................3-6
3-4-8. Operating Cursor Prev..................................................................................................3-7
3-4-9. Compensation Level Display...........................................................................................3-7
3-4-10. Executing Record.......................................................................................................3-7
3-4-11. Executing Delete........................................................................................................3-7
3-4-12. Readout Mode Setting..................................................................................................3-7
3-4-13. Executing Reset.........................................................................................................3-7
3-5. INFORMATION Menu.......................................................................................................3-8
3-5-1. Displaying the Serial Number..........................................................................................3-8
3-5-2. Displaying the Version Number........................................................................................3-8
3-5-3. Executing Self Diag....................................................................................................3-8
3-5-4. Executing Log Dump..................................................................................................3-12
3-5-5. Setting PC Remote Disp...............................................................................................3-12
3-5-6. Setting All Disp.......................................................................................................3-12
MCC-3000MT 2

4. Electrical Alignment
4-1. Adjustment in MAINTENANCE Menu......................................................................................4-1
4-1-1. Test Saw Setting........................................................................................................4-1
4-1-2. Black Shading Adjustment.............................................................................................4-1
4-1-3. White Shading Adjustment.............................................................................................4-2
4-1-4. Flare Adjustment.......................................................................................................4-3
5. Spare Parts
5-1. Note on Repair Parts..........................................................................................................5-1
5-2. Exploded Views...............................................................................................................5-2
5-3. Electrical Parts List..........................................................................................................5-10
5-4. Supplied Accessories........................................................................................................5-41
6. Block Diagrams
Overall..................................................................................................................................6-1
7. Schematic Diagrams
AVP-18.................................................................................................................................7-1
CN-3534...............................................................................................................................7-25
CN-3549...............................................................................................................................7-25
CN-3550...............................................................................................................................7-26
CN-3571...............................................................................................................................7-26
DPR-340...............................................................................................................................7-27
KY-687................................................................................................................................7-52
PS-772.................................................................................................................................7-57
RE-309................................................................................................................................7-58
TR-150................................................................................................................................7-59
Frame Wiring..........................................................................................................................7-62
8. Board Layouts
AVP-18.................................................................................................................................8-1
CN-3534................................................................................................................................8-2
CN-3549................................................................................................................................8-2
CN-3550................................................................................................................................8-2
CN-3571................................................................................................................................8-2
DPR-340................................................................................................................................8-3
KY-687.................................................................................................................................8-4
PS-772..................................................................................................................................8-4
RE-309..................................................................................................................................8-4
TR-150..................................................................................................................................8-5
Board Parts Location...................................................................................................................8-6
MCC-3000MT 3

Manual Structure
Purpose of this manual
This manual describes the information items that premise the service based on the components parts assuming use of
system and service engineers.
Related manuals
The following manuals are available in this model.
If this manual is required, please contact your local Sony Sales Office/Service Center.
• Instructions for Use (Supplied with this unit)
This manual is necessary for application and operation of this unit.
• Protocol Manual of Remote (9-pin) Connector (Available on request)
This manual explains the protocol for controlling this unit via the RS-232C (9-pin serial remote).
Schematic diagrams, board layouts and spare parts
Following boards cannot be replaced on the board-level service or part-level service. So schematic diagrams, board
layouts and spare parts are not described in this manual.
• CD-63 board
• CD-64 board
• CD-67 board
• TR-142 board
MCC-3000MT 5

Section 1
Service Overview
1-1. Power Supply
1-1-1. Power Specifications
Power is supplied to this unit through the DC IN (DC power input) connector on the rear of the unit.
Note
Be sure to use power of this unit within the following range of power voltage and current.
• Power voltage: DC 24 ±2.4 V
• Consumption current: 1.5 A (instantaneous current 3.0 A)
DC IN Connector (Hosiden TCS7960-53)
3
2
1
Pin No.
1 DC IN
2GND
3NC
1-1-2. DC Power Cable
Use a Hosiden’s DC power plug for connection to the DC IN (DC power input) connector.
DC power plug: TCP8927-53
We recommend a power cable wire having rating of rated voltage 60 V or more and allowable current 7 A or more.
MCC-3000MT 1-1

1-2. Installation Space
1-2-1. CCU (Camera Control Unit)
Unit: mm
34188
230
150
150
7.5
200
MCC-3000MT 1-2

1-2-2. CHU (Camera Head Unit)
Unit: mm
(50)
w=35
h=45
1-2-3. Tripod Adaptor (Supplied Accessories)
Unit: mm
For tripod 1/4" -20UNC
(P=1.270) JIS B 7103
(40)
(32) (6)
MCC-3000MT 1-3

1-3. Board Location
PS-772 (Camera B)
PS-772 (Camera A)
TR-150
(Camera B)
TR-150 (Camera A)
CN-3549
CN-3571CN-3534
RE-309
KY-687
DPR-340 (Camera A)
A
VP-18 (Camera A)
CN-3550 (Camera A)
CN-3550 (Camera B)
AVP-18 (Camera B)
DPR-340 (Camera B)
MCC-3000MT 1-4

1-4. External Connectors
1-4-1. Signal Inputs and Outputs
13
Camera head
connector
Camera Control Unit (CCU) Rear Side
256
4
Input Signals
1. HD SDI OUT
BNC type, HD-SDI output signal
2. VIDEO OUT
BNC type, Composite video output signal
3. EXT SYNC IN
BNC type, analog HD (3-level sync) of SD (2-level sync)
sync signal input
4. REMOTE
5
96
1
- External View -
D-sub 9-pin, Female, RS-232C
No
.
Signal I/O Specifications
1 NC — No connection
2 TXD OUT O Transmitted data
3 RXD IN I Received data
4 NC — No connection
5 GND — GND
6 NC — No connection
7 NC — No connection
8 NC — No connection
9 NC — No connection
5. USB (For maintenance only/Mounted three
ports)
15
- External View -
5-pin, mini-B, USB2.0 Hi-Speed
No
.
Signal I/O Specifications
1 VCC O USB Vcc (+5 V)
2 D - I/O USB -
3 D + I/O USB +
4 ID — No connection
5 GND — GND
6. DC IN
1
2
3
- External View -
3-pin, Female
No
.
Signal I/O Specifications
1 +24 V I +12 to 24 Vdc
2 GND — GND
3 NC — No connection
MCC-3000MT 1-5

1-5. Functions of Onboard Switches
1-5-1. AVP-18 Board
AVP-18 board (Side A)
S200
S602
S1201
S1200
S600
S603
Note
Never change the settings of “Factory use” switches.
Ref. No. (Address) Bit Name Description Factory Setting
S200 (E-4) — — LCD ON/OFF (Factory use) OFF
S600 (A-2) — — POWER (Factory use) OFF
S602 (A-2) 1 — POWER (Factory use) OFF
2 — POWER (Factory use) OFF
S603 (A-3) — — POWER (Factory use) OFF
S1200 (C-4) — — ICE (Factory use) Center
S1201 (C-4) — RESET System reset (Factory use) —
MCC-3000MT 1-6

1-5-2. DPR-340 Board
DPR-340 board (Side B)
S200
S1000
S1100
S1300
Note
Never change the settings of “Factory use” switches.
Ref. No. (Address) Bit Name Description Factory Setting
S200 (B-2) — — For test OFF
S1000 (A-3) — SxS SEL With or without SxS express card board OFF
S1100 (B-3) 1 BCT1 Mode setting ON
2 BCT2 Mode setting OFF
3 BCT3 Mode setting ON
4 BCT4 Mode setting ON
S1300 (E-1) 1 JTAG SW1 For FPGA (Factory-use) OFF
2 JTAG SW2 For FPGA (Factory-use) OFF
3 JTAG SW3 For FPGA (Factory-use) OFF
4 JTAG SW4 For FPGA (Factory-use) OFF
MCC-3000MT 1-7

1-6. Circuit Description
1-6-1. CMOS Block System
CD-63/64/67 Board
The CMOS image sensor receives the three primary colors of R, G and B that are separated from the incoming light by
the prism. The CMOS image sensor converts the incoming primary color to electric signal. The built-in 12-bit column
A/D converters then convert the R, G and B analog video signals to the digital video signals respectively.
The electronic shutter, analog gain amplifier and black level clamp functions are also provided in the above boards.
The CD-67 board is for the R-channel signal, the CD-63 board is for the G-channel signal and the CD-64 board is for
the B-channel signal.
The CMOS image sensor receives the sync signal and the serial communication signal from the TR-142 board. The 12-
bit digital video signals that are supplied from the CMOS image sensors pass through the EMI filters (FL1 to FL7) and
are input to the TR-150 board.
Various decoupling capacitors and the damping resistors are also mounted in the above boards.
IC4 of the CD-63/64/67 board is a temperature sensor that sends the temperature data to the CAMERA MICON (IC111/
AVP-18 board) via I²C bus.
1-6-2. CHU-CCU Transmission Block
The digital video signal that is output from the CMOS image sensor in the CHU is sent to the CCU by packing the digital
video signal into 3 Gbps serial data. At the same time, various sync signals and the I²C communication signal that are
required to drive the CMOS image sensor are transferred by multiplexing/demultiplexing these signals into the 3 LVDS
signals.
TR-142 Board
The R/G/B digital video signals that are output from the CMOS image sensor in the CHU are sent to the CCU by packing
these signals into the 5-pair LVDS data by IC101 and by passing through IC103 serializer/cable driver. Since the sync
signals and the communication signal that are output from the CCU are multiplexed into serial data, they are de-
multiplexed by IC101 and are output to the CMOS.
On the other hand, the return communication signal and others from the CMOS to the CCU are multiplexed into a single
LVDS data by IC101 and are transferred.
TR-150 Board
The 3 Gbps serial data that is transferred from the CHU passes through the IC103 cable equalizer and is de-serialized
to the 5-pair LVDS data by the receiver of IC102. Then the signal receives de-packing at IC101, decoded to the R/G/B
digital video signal and is output to the DPR-340 board.
The sync signals and the communication signal to the CMOS are multiplexed into the two LVDS data by IC101 and is
output to the CHU. At the same time, the return communication signal from the CMOS is demultiplexed by IC101 and
output to the DPR-340 board.
1-6-3. Camera Block System
DPR-340 Board
The DPR-340 board consists of the Camera Signal Processor IC (IC100) and the CAMERA MICON (IC111/AVP-18
board) whereas the Camera Signal Processor IC (IC100) performs various processing on the digital video signal supplied
from the CMOS image sensor, and the CAMERA MICON (IC111/AVP-18 board) performs control of IC100 and other
various controls such as control of the CMOS image sensor and of lens. The output digital video (Y/C) signal is sent to
the next circuit the video (baseband video) signal processing circuit.
Transmission block (reception): The 12-bit digital video (RGB) signals supplied from the TR-150 board first enter the
camera signal processor IC (IC100).
MCC-3000MT 1-8

In the camera signal processor IC (IC100), average value, peak value of the RGB digital video signals that are required
for the following AUTO operations of the camera are detected. The detected signal are sent to the CAMERA MICON
(IC111/AVP-18 board).
• Auto white balance
• Auto black balance
• Auto focus
• Auto iris
• Auto knee
The digital video signal from the CMOS image sensor enters first the selector circuit selecting either the digital video
signal from the CMOS image sensor or the internal TEST signal. The output video signal from the selector enters the
compensation circuits consisting of the CMOS imager-related compensation circuit and the lens-related compensation
circuit. The video signal then receives the white balance processing, and the matrix signal and the detail signal are added
to the video signal. The video signal then receives the pedestal control, knee compensation, gamma correction and white/
black clip processing. The video signal finally enters the baseband processing IC (IC300) via PLD IC200.
1-6-4. Video Signal System
DPR-340 Board
The baseband processing IC (IC300) performs the overall baseband processing of video and audio signals with a single
chip IC containing the various scaler functions (supporting the multiple format outputs), various OSD functions, PLL
function (54 MHz → 74 MHz) and CPU.
The baseband processing IC (IC300) provides the following outputs:
• HD-SDI (digital): To AVP-18 board
• Composite (analog): To KY-687 board
The input/output signals of the baseband processing IC (IC300) are the following signals:
• MPEG encoder/decoder I/F signal (digital): To IC601
• Audio I/F signal (digital): To IC306 on the AVP-18 board
Peripheral circuits of the baseband processing IC (IC300) are the master clock 54 MHz VCXO (X300) control circuit
(IC307, etc.) and the Mobile DDR SDRAM memory (IC500, IC501).
Peripheral circuits of the built-in CPU are FLASH ROM (IC406) and SDRAM (IC403).
The baseband processing IC (IC300) is controlled by the system controller (IC700) on the AVP-18 board. The SDI
Copro, the audio system and the control of the output systems are controlled by the built-in CPU inside IC300.
1-6-5. System Control
AVP-18 Board
The 32-bit RISC CPU (ARM) with ARM core is built-in as the system controller (IC700).
It has the peripheral interface functions of SDRAM, USB, SCI, and I²C. It operates on a 27 MHz clock (X700).
FLASH ROM (IC708), SDRAM (IC711), and EEPROM (IC819) are mounted as the peripheral ICs.
It performs the system control through serial communication with IC300 of the video signal system, IC600 of the media
recording/playback system, and IC111 of the image processor on the DPR-340 board.
Main functions of the system controller and peripherals
1. Reading operation switch information
Reading the switch information and the LED control are performed by I²C bus communication with each sub-
microprocessor.
• Front switch: IC202, IC300, IC400 on the KY-687 board
• Power supply switch: IC1202
2. Real time clock IC (RTC) control
The real time clock IC (IC710) is built in.
The real time clock IC (IC710) is not backed up by a lithium coin battery, and the time after the power supply is
turned on is read or set via IC700 on the AVP-18 board.
MCC-3000MT 1-9

3. Power supply voltage detection
The power supply voltage at the RE-309 board is measured by the A/D port on IC1202 on the AVP-18 board, and
it is posted to the system controller as the input voltage value.
4. Power system control
IC1202 on the AVP-18 board checks that the power switch on the unit is turned ON, and turns on the system
controller of IC700.
After that, it controls the power for each circuit block according to the system controller.
The system controller controls the respective power supply systems in the AVP-18 and DPR-340 boards according
to the operation mode of the device, via the POWER SUPPLY MICON (IC1202).
By turning off the power systems to unnecessary circuits blocks, power can be saved.
1-6-6. SDI System
AVP-18 Board
The Copro (IC1300) receives the parallel video signal from IC300 on the DPR-340 board and performs serial-parallel
conversion, and outputs the SDI signal.
And the Copro (IC1300) performs embedding audio signal and time code.
Output SDI signals are supplied to CN1300 and CN1301 through the cable driver (IC1305).
The PLL circuit is used to reduce jitter of the HD-SDI clock signal.
The Copro (IC1300) is controlled by IC300 on the DPR-340 board through 4-line serial communication.
The FPGA program is stored in the IC1600 ROM, and JTAG can be used to overwrite the data from IC700.
1-6-7. Power System
RE-309 Board
The RE-309 board is a DC/DC converter board for conversion from input 24 VDC to output 12 VDC. This board also
outputs the ALERT signal when output overvoltage protection or output overcurrent protection is activated.
• Input 24 VDC: 1 channel
• Output 12 VDC: 3 channels
• LED_ALERT (10 VDC blinking signal): 1 channel
1. Operation of input system and protection function
The protection function outputs a voltage of 12 VDC immediately when the input power voltage reaches the
activation voltage.
The normal input power voltage value for usual operation is 24 V ±10%.
The input protection function works as follows.
• Activation voltage: When the input power voltage rises to approx. 18.0 V, the relay is turned on to activate
the main converter IC.
• Breaking voltage: When the input power voltage lowers to approx. 15.7 V, the relay is turned off to stop the
main converter IC.
• Protection of reverse power connection: If input voltage polarity is reversely connected, the relay is
immediately turned off to stop the main converter IC.
• Protection of input system short-circuit: A 3.15 A fuse is provided in the 24 V power line to blow the fuse at
an input overcurrent to protect the circuit.
MCC-3000MT 1-10

2. Operation of 12 VDC output system and protection function
The DC/DC converter function for 12 VDC output consists of a power IC and a peripheral circuit. The 12 V power
output system is divided into the following three channels.
Output system:
• One channel to the KY-687 board
• One channel to the AVP-18 board (Camera A side)
• One channel to the AVP-18 board (Camera B side)
The output protection function works as follows.
• Protection of output overvoltage: When the output power voltage rises to approx. 16 V, the main converter IC
function is disabled and the 12 V output is shut off. At this time, the LED_ALERT signal is output. Automatic
reset is not made and power must be turned on again because this state is maintained.
• Protection of output overcurrent: When the total output current of three channels reaches approx. 3.95 A, the
main converter IC function is disabled and the 12 V output is shut off. At this time, the LED_ALERT signal
is output. Automatic reset is not made and power must be turned on again because this state is maintained.
• Protection of output short-circuit: When the output is short-circuited, the 12 V output is shut off by the
overcurrent detection function of the main converter IC. When the cause of the short-circuited has been cleared,
automatic reset is made and 12 V is output again.
3. Power output for alarm LED (LED_ALERT)
When the output overvoltage protection or output overcurrent protection function is activated, the 12 V output is
shut off. Power to turn on the alarm LED on the non-powered KY-687 board is supplied separately.
Output system:
• One channel to the KY-687 board
When the overvoltage protection or overcurrent protection function is working, the LED_ALERT signal is output.
The LED_ALERT signal is created by the 3-pin regulator for internal reference power voltage and the timer IC.
The output is a blinking signal of approx. 10 V/0.65 seconds and 0 V/0.33 seconds (max. 20 mA).
AVP-18 Board
The AVP-18 board consists of a power circuit and a power microcomputer (IC1202).
However, some low power voltages are contained on the DPR-340 board.
1. Operation of input power (UNREG) system
UNREG power is input and the AVP-18 board becomes the EVER power state.
In this state, ON or OFF of the power switch can be recognized.
When the power microcomputer (IC1202) recognizes ON of the power switch, the power microcomputer turns on
the system control power and controls power for each block in accordance with instructions of the system controller
(IC700).
The normal input power (UNREG) value is within a range of approx. +10.5 V to +18 V.
• Protection of input overvoltage:
When the UNREG power voltage is high, the overvoltage protection circuit is activated at the set value of
+17.9 V to shut down the input voltage. This circuit allows automatic restoration of power immediately when
the input voltage lowers to +17.9 V or less.
• Protection of input low voltage:
When the UNREG power voltage is low, the low-voltage protection circuit is activated approximately at the
set value of +10.5 V by the power microcomputer control to shut down the input voltage. When the input
power voltage rises to +10.5 V or more, power is immediately restored automatically by the power
microcomputer control.
• Detection of overcurrent:
The AVP-18 board is provided with an overcurrent detection circuit consisting of IC904. The set value is
approx. 4.3 A. Even if IC904 is reset after an overcurrent has been detected, automatic reset is not made and
power must be turned on again.
• Protection of reverse power connection:
If input voltage polarity is reversely connected, Q901 on the AVP-18 board is immediately turned off and the
GND side of the UNREG power is shut off to activate the protection function.
MCC-3000MT 1-11

2. DC/DC converter function
Power supply is divided into 23 voltages that are grouped into four blocks as shown below.
• Six voltages for audio/video signals: +13.5 V, -4.6 V, +4.6 V, etc.
• Five voltages for the system controller: +4.6 V, +3.1 V, +2.5 V, etc.
• Six voltages for media recording and playback: +3.1 V, +2.5 V, +1.8 V, etc.
• Six voltages for camera (image processor): +4.6 V, +2.5 V, +3.3 V, etc.
Each power voltage in these blocks is turned on and off in accordance with the power sequence control by the power
microcomputer (IC1202).
• Protection of short-circuit in each power system:
Output voltage and current in each power system are monitored, and circuit settings are made to activate the
protection circuit for each block.
The protection circuit is not reset automatically even after the cause of the short-circuit has been cleared, and
power must be turned on again.
MCC-3000MT 1-12