Samsung SDC-30, Руководство по обслуживанию

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2. Reference Information
2-1 Circuit description
2-1-1 DSC
Digital camera(SDC-30/33), is an image-input device that connects to a PC. It’s small and light welght, supplies
high quality images and has a large capacity (4MB/2MB). The digital camera consists of 3 sections: Camera,
signal processing and storage.
1. Camera
The camera is similar to a camcorder but adapts a scanning method of 525/30 (which can read an entire image of
in one frame, whereas the camcorder’s scanning method is 525/60.
Photo-exposure is controlled by the electronic shutter through timing generator and CCD driver IC (where as a
camcorder controls the exposure using an IRIS).
Main function of this part is to control the photo-exposure in accordance with the brightness, and to store the
image in DRAM.
2. Digital Signal Processing
Image information of 1 frame is temporarily stored in DRAM. Image information stored in DRAM is the
digitalized CCD signal from the camera. It needs additional image signal processing by the 32-bit microprocessor.
The image signal processing done by the microprocessor includes white balance, shape adjustment and Y/C
signal conversion.
3. Storage
After image signal processing, an image signal compression technique allows more image to be stored in the
limited memory. In the case of SDC-30/33, 10:1 compression is normally executed for standard JPEG specification.
After compression, the image information is stored in the nonvolatile flash memory : Max. 45/22 frame for
VGA(640*480), and max 180/90 frame for QVGA(320*240).
The image can be stored, edited, and printed by the PC image editing program that is supplied with the camera.
2-1-2 Power
LCD MICOM generates the control signal that turns on the system (5V). When the power is on, the signal turns
on IC140 PWM IC which outputs 5V through T141.
When shot key is pressed, the signal for output is generated from MICOM, which turns on IC120 PWM IC and
outputs 5V, -7V, and 15V through T121. After the shot, the camera control signal turns off the power supply with-
in. 5sec (through T121).
2-1-3 DC/DC block operation description
2-1-3(A) DC/DC BLOCK CONSISTS OF THREE COMPONENTS AS BELOW.
1. EVER5V
EVER5V consists of S8420 (IC100) IC and the assocciat battery circuitry (CN101 Pin2) is input to
IC100 (S8420). Pin 8 and 5V voltage are generated internally and are output to pins 1 and 7. EVER5V power
(Pin 1) is input to the function board for LCD MICOM (IC601) drive, POWER S/W (LED01) driving power, and
PULL-UPvoltage. RESET output of IC100 Pin 5, which changes from low to high at the power input, is connected
to LCD MICOM RESET PIN (and resets LCD MICOM).
Samsung Electronics 2-1