Circuit Description - Sony PMW-EX1 Service Manual

1-3. Circuit Description

1. CMOS Block System
BI-202/203/204 Board
The BI-202, BI-203 and BI-204 boards are the rigid
flexible boards connecting the CMOS image sensors (IC1)
to the DPR-289 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 respective-
ly.
The electronic shutter, analog gain amplifier and black
level clamp functions are also provided in the above
boards.
The BI-202 board is for the R-channel signal, the BI -203
board is for the G-channel signal and the BI -204 board is
for the B-channel signal.
The CMOS image sensor receives the sync signal and the
serial communication signal from the DPR-289 board. The
12-bit digital video signals that are supplied from the
CMOS image sensors pass through the EMI filters (FL1 to
FL4) and are input to the DPR-289 board.
Various decoupling capacitors and the damping resistors
are also mounted in the above boards.
IC3 of the BI-203 board is a temperature sensor that sends
the temperature data to the CAMERA MICON (camera u-
processor: IC314) on the DPR-289 board via I
2. Camera Block System
DPR-289 Board
The DPR-289 board consists of the Camera Signal Proces-
sor IC (IC100) and the CAMERA MICON (camera u-
processor: IC314) 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 (IC314) 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.
The 12-bit digital video (RGB) signals supplied from the
CMOS block (BI-202, BI-203 and BI-204 boards) first
enter the camera signal processor IC (IC100). In the
camera signal processor IC (IC100), average value, peak
value of the RGB digital video signals that are required for
1-4
the following AUTO operations of the camera are detected.
The detected signals are sent to the CAMERA MICON
(camera u-processor: IC314).
. 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
(IC400).
The pixel number conversion processing from 1920/1080
to 1440/1080 or 1280/720 is also performed inside IC100.
The CAMERA MICON (camera u-processor: IC314)
performs the overall control over the entire camera system
and is controlled by the camera system controller
(IC1600).
Peripheral ICs of the CAMERA MICON (camera u-
processor: IC314) are FLAH ROM (IC312) and SRAM
(IC313).
2 C bus.
3. Video Signal System
DPR-289 Board
The digital video (Y/C) signal output from the camera
signal processor IC (IC100) enters the baseband processing
IC (IC400).
The baseband processing IC (IC400) 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 (IC400) provides the follow-
ing outputs:
. HD/SD-SDI (digital): To TX-115 board
. HD/SD Component (analog): To JK-77 board
. Composite (analog): To JK-77 board
. S-Video (analog): To JK-77 board
. LCD signal (digital): To IF-1072 board
. EVF signal (analog): To DR-621 board
The input/output signals of the baseband processing IC
(IC400) are the following signals:
PMW-EX1