Nikon COOLPIX 2200 Repair Manual page 45

3. IC904 (V Driver)
V driver is necessary in order to generate the clocks
(vertical transfer clock, horizontal transfer clock and
electronic shutter clock) which driver the CCD.
IC904 is V driver. In addition the XV1-XV4 signals
which are output from IC101 are the vertical transfer
clocks, and the XSG signal which is output from IC102
is superimposed onto XV1 and XV3 at IC904 in order
to generate a ternary pulse. In addition, the XSUB signal
which is output from IC101 is used as the sweep pulse
for the electronic shutter.
4. IC905 (CDS, AGC Circuit, A/D Converter and
H driver)
The video signal which is output from the CCD is input
to Pin (27) of IC905. There are inside the sampling hold
block, AGC block and A/D converter block.
The setting of sampling phase and AGC amplifier is car-
ried out by serial data at Pin (32) of IC935. The video
signal is carried out A/D converter, and is output by
10-bit. A H driver is inside IC905, and H1, H2 and RG
clock are generated at IC905.
0~18 dB 6~42 dB
CDS PxGA VGA
CCDIN
INTERNAL
PRECISION
RG
HORIZONTAL
4
DRIVERS
H1-H4
AD9948
GENERATOR
HD
Fig. 1-2. IC905 Block Diagram
REFT REFB
VREF
10
10-BIT
ADC
CLAMP
CLOCKS
TIMING
CORE
SYNC INTERNAL
REGISTERS
SL
VD SCK SDATA
- E2 ･ E2200 -
5. Lens drive block
5-1. Focus drive
The four control signals (FIN1, FIN2, FIN3 and FIN4)
with different phases which are output from the ASIC
expansion port (IC106) are converted into drive pulses
(FOUT1, FOUT2, FOUT3 and FOUT4) by the motor
driver (IC951), and are then used to drive the stepping
motor for focusing operation. Detection of the standard
focusing positions is carried out by means of the photo-
interruptor (FOCUS PI) inside the lens block.
5-2. Iris and shutter drive
The two control signals (IIN1 and IIN2) which are out-
put from the ASIC expansion port (IC106) are converted
into drive pulses (DP1 and DP2) by the motor driver
(IC951), and are then iris opened/little and moved.
The two control signals (SIN1 and SIN2) which is out-
put from the ASIC (IC101) is converted into a drive
pulse (SHUTTER 1 and SHUTTER 2) by the motor
driver (IC951), and are then shutter opened and closed.
5-3. Zoom drive
The two control signals (ZIN1 and ZIN2) which are out-
put from 8-bit micro-processor are converted into drive
pulses (ZOOM_DC1 and ZOOM_DC2) by the motor
drive (IC951), and are then used to drive the DC motor
DOUT
for zoom operation.
Detection of the standard zoom positions is carried out
HBLK
by means of the photointerruptor (ZOOM RESET1) in-
CLP/PBLK
side the lens block. Getting of the zoom positions is car-
CLI
ried out by means of the two photo-interrupters (ZOOM
PLUSE1 and ZOOM PLUSE2) by counting 8-bit micro-
processor inside the lens block.
VAA23001-R.3626.A