Sanyo VPC-CG20 Service Manual page 7

8. Key Operaiton
For details of the key operation, refer to the instruction manual.
SCAN
IN
0
SCAN
OUT
0
POWER
1 UP
2 PW_TEST
9. Receiving user operations showing that the camera has been turned on
When the battery is installed, the 3.2V power supply which is output from IC501 is constantly being input to the power sequencer
of the ASIC, and it monitors user operations that generate a P-ON request (such as POWER key input and panel opening).
10. Power control
When a power on request is generated by the user, the PON signal is set to High and the DC/DC converter turns on. In addition,
the resetting of the CPU inside the ASIC is canceled. This causes all blocks and memories other than the power sequencer of the
ASIC to start operating.
ON/OFF control for the 1.8V, 2.8V and 3.3V power supplies for the CMOS sensor is carried out by the ASIC setting PAON1 and
PAON2 to High or Low, and also by I2C signal sent to IC501.
Shooting mode
11. Clock backup
The clock backup is carried out by IC501.
The ASIC gets clock information via I2C when necessary.
1
PLAY
DOWN
-
Table 2-2. Key Operation
Power OFF
Play mode
Table 2-3. Power Control
2 3
MENU VREC
LEFT RIGHT
TEST -
ASIC/memory/LCD
1.1V, 1.8V, 3.3V
OFF
ON
ON
– 7 –
4
-
SET
-
CMOS
1.8V, 2.8V, 3.3V
OFF
ON
OFF