Sanyo VPC-E10 Service Manual page 11

3. Key Operaiton
For details of the key operation, refer to the instruction manual.
SCAN
IN
SCAN
OUT
0
MENU
1
2
3
4. Power Supply Control
The 8-bit microprocessor controls the power supply for the overall system.
The following is a description of how the power supply is turned on and off. When the battery is attached, IC501 is operating and
creating 4.2 V, a regulated 3.2 V voltage is normally input to the 8-bit microprocessor (IC301) by IC302, clock counting and key
scanning is carried out even when the power switch is turned off, so that the camera can start up again.
When the power switch is off, the 8-bit microprocessor halts the high speed built-in oscillation clock (8MHz oscillation, 4MHz
operation), and operates 32.768 kHz of subclock.
When the battery is removed, the 8-bit microprocessor power switches the battery for memory backup by IC302, and operates at
low consumption. At this condition, the 8-bit microprocessor halts the high speed built-in oscillation clock, and operates clock
counting by sub clock.
Also, the battery for backup is charged 16 hours from it to be attached.
When the power switch is on, the 8-bit microprocessor starts processing. The 8-bit microprocessor first sets both the PON signal
at pin (27) to High, and then turn on the power circuit. After PON signal is to High, sets external port of ASIC after approximately
100 ms. According to setting of this external port, carry out setting of the operating frequency, oscillation control and PAON and
PAON3 control (analog system power) from ASIC. Also, it starts communication with ASIC, and confirms the system is operative.
When LCD panel turns on, set BL ON signal at pin (28) to High, and turn on the backlight power.
When the power switch is off, the lens will be stowed, and PON and BL ON signals to Low and the power supply to the whole
system is halted. The 8-bit microprocessor halts the high speed built-in oscillation clock, and set operation mode of clock ocillation.
Power supply voltage
Playback mode
Shooting mode (LCD)
USB connection
1
0
SCENE
LEFT RIGHT
TELE
WIDE
- -
Table 5-2. Key Operation
Power OFF
Shooting
Table 5-3. Power supply control
2 3
PLAY
OK
UP DOWN
-
-
PW_TEST
TEST
ASIC,
CCD
memory
12 V, -6 V
1.26 V, 3.25 V
3.4 V
1.8 V
OFF OFF
ON OFF
OFF
ON
ON
OFF
ON
– 11 –
8bit
CPU
3.2 V
32KHz
4MHz
4MHz
ON 4MHz
4MHz
LCD
MONITOR
3.0 V
OFF
ON
ON
ON
OFF