Sanyo VPC-E6 Service Manual page 9

3. Key Operaiton
For details of the key operation, refer to the instruction manual.
SCAN
IN
SCAN
OUT
← LEFT
0
1 MENU
2
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, a regulated 3.2 V
voltage is normally input to the 8-bit microprocessor (IC301) by IC302, so that 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 battery is removed, the 8-bit micro-
processor operates in sleep mode using the backup lithium secondary battery. At this time, the 8-bit microprocessor only carries
out clock counting, and waits in standby for the battery to be attached again. When a switch is operated, the 8-bit microprocessor
supplies power to the system as required.
The 8-bit microprocessor first sets the P ON signal at pin (40) to high, and then turns on the DC/DC converter. After this, high
signals are output from pins (26) and (31) so that the ASIC is set to the active condition. Once it is completed, the ASIC returns
to the reset condition, all DC/DC converters are turned off and the power supply to the whole system is halted.
Power voltage
Power OFF
Power switch ON-
CAMERA
Shutter switch ON
Play back
Note) 4 MHz = Main clock operation, 32 kHz = Sub clock operation
5. 16-bit A/D circuit (Audio)
This circuit converts the audio signals (analog signals) from the microphone to 16-bit digital signals.
6. 16-bit D/A circuit (Audio)
The audio signals which were converted to digial form by the 16-bit A/D circuit are temporarily to a sound buffer and then
recorded in the SSFDC card. During playback, the 16-bit D/A circuit converts these signals into analog audio signals.
0 1
↑ UP
-
1st
2nd
Table 5-2. Key Operation
Auto power OFF
LCD finder
Table 5-3. Camera Mode (Battery Operation)
2 3
→ RIGHT
↓ DOWN
TELE WIDE
PW_TEST
TEST
ASIC,
CCD
memory
5 V (A)
3.3 V
+15 V (A) etc.
OFF OFF
ON
OFF
ON ON
ON ON
ON
OFF
– 9 –
4
OK
PLAY
PW-ON
8 bit LCD
CPU MONITOR
3.2 V
+15 V (L)
(ALWAYS)
32KHz OFF
4 MHz ON
4 MHz ON
4 MHz ON
4 MHz ON