Nikon COOLPIX S550 Repair Manual page 78

INC
VMA21024-R.3750.A
4. Lens drive block
4-1. Zoom drive
The zoom drive signals (ZOUT1 and ZOUT2) are output from
the motor driver IC (IC951) by parallel signals (ZIN1 and ZIN2)
which is output from the ASIC (IC101). The DC motor is used
to drive by these drive signals, and then zooming lens is op-
erating. Detection of the standard zooming positions is carried
out by the ASIC (IC101) detecting the signal (ZPROUT) from
the photointerruptor inside the lens block. Also, getting of the
zooming positions is carried out by the ASIC (IC101) counting
the photointerruptor (ZPIOUT).
4-2. Focus drive
The focus drive signals (FOUT_A+, FOUT_A-, FOUT_B+ and
FOUT_B-) are output from the motor driver IC (IC951) by se-
rial data signals (LENS_SD, LENS_CK and LENS_EN) which
is output from the ASIC (IC101). The stepping motor is used
to drive by these drive signals, and then focusing lens is op-
erating. Detection of the standard focusing lens positions is
carried out by the ASIC (IC101) detecting the signal (FPIOUT)
from the photointerruptor inside the lens block.
4-3. Iris drive
The drive signals (IOUT1 and IOUT2) are output from the
motor driver IC (IC951) by iris drive signals (IIN1 and IIN2)
which is output from the ASIC (IC101). The moving coil motor
is used to drive by these drive signals, and then used to drive
the iris steps.
4-4. Shutter drive
The drive signals (SOUT1 and SOUT2) are output from the
motor driver IC (IC951) by shutter drive signals (SIN1 and
SIN2) which is output from the ASIC (IC101). The moving
magnet motor is used to drive the shutter constant by these
drive signals, and then mecha shutter is opened and closed.
– 5 –
- E･ S550 -