Outline Of Circuits; Power Supply Control; Power Supply Block Diagram; Power Control Sequence - Canon PowerShot A100 Service Manual

CHAPTER 2. TECHNICAL DESCRIPTION

2. Outline of Circuits

2.1 Power Supply Control

The power supply is controlled by the CPU mounted on the main PCB ass'y.

2.1.1 Power Supply Block Diagram

MAIN PCB ASS'Y
BATTERY
or
DC_IN
VBATT
FUSE

2.1.2 Power Control Sequence

E1, E2, E3
DC/DC
CONVERTER
E1
OUTPUT
E2
OUTPUT
E3
OUTPUT
Fig. 2 Power System Block Diagram
"Battery is Installed" or "DC-IN"
Turn on the PLAY switch
Playback Mode
LCD
ON
(E3)
CPU
(2.5V)
REG
for DSP
(2.5V)
REG
VCC1 (3.3V)
for System Control
VCC1A (3.3V)
VCC1M (3.3V) for Motor Drive
VDD2 (15V)
VEE2 (–7.5V) for Image Process (CCD etc.)
VCC2 (4.2V)
VDD34 (13.5V)
for LCD
VCC3 (4.2V)
REG (3.0V) for System Control
VBATT
Open the Barrier (E1)
Shooting Mode
LCD
ON
LCD OFF
(E2) (E2, E3)
2-2