SANYO VPC-MZ2EX, VPC-MZ2, VAR-GA4U, VAR-GA4EX, VAR-GA4E POWER CIRCUIT DESCRIPTION

1-4. PW1 POWER CIRCUIT DESCRIPTION
1. Outline
This is the main PW1 power circuit, and is comprised of the following blocks. Switching controller (IC501) Digital and LCD system and 5.0 V system power output (L5005, Q5015, D5005, C5036, C5037) Digital 3.3 V system power supply (L5002, Q5003, D5002, C5018) Digital 3.4 V system power supply (L5003, Q5009, D5004, C5029) Series regulator (IC502) Digital 2.5 V system power supply (Q5007, C5025, C5026) Analog system 5 V power supply (L5008, Q5020, D5006, C5045)
2. Switching Controller (IC501)
This is the basic circuit which is necessary for controlling the power supply for a PWM-type switching regulator, and is pro­vided with four built-in channels, only CH1 (digital 3.3 V), CH3 (5 V system), CH2 (digital 3.4 V) and CH4 (analog system 5 V) are used. Feedback from 3.3 V (D) (CH1), 3.4 V (D) (CH2), 5 V (D) (CH3) and 5.0 V (A) power supply outputs are re­ceived, and the PWM duty is varied so that each one is main­tained at the correct voltage setting level.
2-1. Short-circuit protection circuit
If output is short-circuited for the length of time determined by the condenser which is connected to Pin (33) of IC501, all output is turned off. The control signal (P ON, P(A) ON and LCD ON) are recontrolled to restore output.
3. Digital 3.3 V Power Output
3.3 V (D) is output. Feedback for the 3.3 V (D) is provided to the switching controller (Pins (1) of IC501) so that PWM con­trol can be carried out.
4. Digital 3.4 V System Power Output
3.4 V (D) is output. Feedback is provided to the swiching con­troller (Pin (12) of IC501) so that PWM control can be carried out.
5. 5 V System Power Output
5 V (D) and 5 V (L) are output. Feedback for the 5 V (D) is provided to the switching controller (Pin (25) of IC501) so that PWM control can be carried out.
6. Series Regulator (IC502)
This is provided with one built-in channel. Digital 3.4 V is in­put, and digital 2.5 V is output.
7. Digital 2.5 V System Power Output
2.5 V (D) is output. Feedback for the 2.5 V (D) is provided to the Pin (7) of IC502. The current of Q5008 base is controled so that the voltage of Q5008 collector is 2.5 V.
8. Analog 5 V System Power Output
5 V (A) is output. Feedback is provided to the swiching con­troller (Pin (36) of IC501) so that PWM control can be carried out.
– 7 –
1-5. PW1 STROBE CIRCUIT DESCRIPTION
1. Charging Circuit
When UNREG power is supplied to the charge circuit and the CHG signal becomes High (3.3 V), the charging circuit starts operating and the main electorolytic capacitor is charged with high-voltage direct current. However, when the CHG signal is Low (0 V), the charging circuit does not operate.
1-1. Power switch
When the CHG signal switches to Hi, Q5406 turns ON and the charging circuit starts operating.
1-2. Power supply filter
L5401 and C5401 constitute the power supply filter. They smooth out ripples in the current which accompany the switch­ing of the oscillation transformer.
1-3. Oscillation circuit
This circuit generates an AC voltage (pulse) in order to in­crease the UNREG power supply voltage when drops in cur­rent occur. This circuit generates a drive pulse with a frequency of approximately 50-100 kHz. Because self-excited light omis­sion is used, the oscillation frequency changes according to the drive conditions.
2. Light Emission Circuit
When RDY and TRIG signals are input from the ASIC expan­sion port, the stroboscope emits light.
2-1. Emission control circuit
When the RDY signal is input to the emission control circuit, Q5409 switches on and preparation is made to let current flow to the light emitting element. Moreover, when a STOP signal is input, the stroboscope stops emitting light.
2-2. Trigger circuit
When a TRIG signal is input to the trigger circuit, D5405 switches on, a high-voltage pulse of several kilovolts is gen­erated inside the trigger circuit, and this pulse is then applied to the light emitting part.
2-3. Light emitting element
When the high-voltage pulse form the trigger circuit is ap­plied to the light emitting part, currnet flows to the light emit­ting element and light is emitted.
Beware of electric shocks.
1-4. Oscillation transformer
The low-voltage alternating current which is generated by the oscillation control circuit is converted to a high-voltage alter­nating current by the oscillation transformer.
1-5. Rectifier circuit
The high-voltage alternating current which is generated at the secondary side of T5401 is rectified to produce a high­voltage direct current and is accumulated at electrolytic ca­pacitor C5144 on the CA3 board.
1-6. Voltage monitoring circuit
This circuit is used to maintain the voltage accumulated at C5144 at a constance level. After the charging voltage is divided and converted to a lower voltage by R5417 and R5419, it is output to the SY1 circuit board as the monitoring voltage VMONIT. When this VMONIT voltage reaches a specified level at the SY1 circuit board, the CHG signal is switched to Low and charging is interrupted.
– 8 –
1-6. SY1 CIRCUIT DESCRIPTION
1. Configuration and Functions
For the overall configuration of the SY1 circuit board, refer to the block diagram. The SY1 circuit board centers around a 8-bit microprocessor (IC301), and controls camera system condition (mode). The 8-bit microprocessor handles the following functions.
1. Operation key input, 2. Clock control and backup, 3. Power ON/OFF, 4. Storobe charge control, 5. Signal input and output for zoom and lens control.
Pin
1~4
5
6
7
8
9
10
11
12 13
14
15
16
17
18
19
20
21
22
23
24 VDD
25 AVSS
26~29 SCAN IN 3~0
30
31 DC IN
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
STBY_LED (GREEN)
Signal
SCAN OUT 0~3
P ON
PA ON
LCD ON
P ON2
VSS
VDD
SELF_LED
STBY_LED (RED)
AVREF_ON
SI
SO
SCK
PRG SI
PRG SO
PRG SCK
AV J AC K
NOT USED
CHG ON
INT_TMP
CHG VOL
BATTERY
AVREF
AVDD
RESET
XCOUT
XCIN
IC
XOUT
XIN
VSS
BAT OFF
SREQ
JOG 0
SCAN_IN5
JOG 1
BR PCON
I/O
O
O
O
O
O
O
O
O
O
O
I/O
O
I/O
O
O
O
O
Outline
Key matrix output
Digital power ON/OFF control H : ON
Analog power ON/OFF control H : ON
LCD power ON/OFF control H : ON
ASIC/CF card power timing control H : ON
-
-
I
I
I
-
-
-
I
I
I
I
I
-
-
I
I
I
I
-
I
I
I
I
I
GND
VDD
Self-timer LED control L : ON
Stand-by LED (green) control L : ON
Stand-by LED (red) control L : ON
A/D converter standard voltage control L : ON
Receiving data (from ASIC)
Sending data (to ASIC)
Communication clock (to ASIC)
Flash memory write receiving data
Flash memory write sending data
Flash memory write communication clock
AV jack connection detection H : AV JACK detection
-
Flash charge control H : ON
VDD
Analog GND
Key scan input
Internal temperature detection input (analog input)
DC JACK/battery detection input (analog input)
Storobe charge voltage detection (analog input)
Battery voltage detection (analog input)
Analog standard voltage input terminal
A/D converter analog power terminal
Reset input
Clock oscillation terminal (32.768 kHz)
Clock oscillation terminal
Flash memory writing voltage
Main clock oscillation terminal (4MHz)
Main clock oscillation terminal
GND
Battery OFF detection
Serial communication requirement (from ASIC)
Jog shuttle input 0
Key scan input 5
Jog shuttle input 1
-
See next page
– 9 –
49 BR OPEN
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
BR CLOSE
CARD
BUZZER
SCAN IN 4
SCAN OUT 4
WAKE UP
SYMUTE
USB
NOT USED
NOT USED -
NOT USED
NOT USED
ASIC TEST 1 O ASIC reset control signal 1
ASIC TEST 2
ASIC RESET
O
O Barrier close control L : Close
I
O
I
O
I
O
I
--
-
-
O
O
Table 4-1. 8-bit Microprocessor Port Specification
Barrier open control H : Open
CF card insertion detection L : Insertion
Buzzer beep tone output H : Pulse output
Key scan input 4
Key scan output 4
-
Audio mute control L : Mute
USB connector detection L : USB detecion
-
-
-
ASIC reset control signal 2
ASIC reset singal
2. Internal Communication Bus
The SY1 circuit board carries out overall control of camera operation by detecting the input from the keyboard and the condition of the camera circuits. The 8-bit microprocessor reads the signals from each sensor element as input data and outputs this data to the camera circuits (ASIC) or to the LCD display device as operation mode setting data. Fig. 4-1 shows the internal commu­nication between the 8-bit microprocessor, ASIC and SPARC lite circuits.
ASIC RESET
S. REQ
8-bit
Microprocessor
Fig. 4-1 Internal Bus Communication System
ASIC SO
ASIC SI
ASIC SCK
ASIC TEST 1
ASIC TEST 2
3. Key Operaiton
For details of the key operation, refer to the instruction manual.
SCAN
SCAN OUT
IN
0
1
2
3
4
0
LEFT
TELE
MODE
STILL IMAGE
--
123
UP
WIDE
SET FLASH MODE BARRIER OPEN
SEQUENTIAL
SHOT
RIGHT
PLAY MODE
INFO
VIDEO CLIP
SHOOTING
-
DOWN
REC MODE
(LCD OFF)
SET UP
-
4
1st shutter
REC MODE
(LCD ON)
PC MODE
-
ASIC
5
2nd shutter
-
BARRIER
CLOSE
TEST
POWER ON
Table 4-2. Key Operation
– 10 –
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 micro­processor operates in sleep mode using the backup capacitor. 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 both the P (A) ON signal at pin (6) and the P ON signal at pin (5) to high, and then turns on the DC/DC converter. After this, low signals are output from pins (62), (63) and (64) so that the ASIC is set to the active condition. If the LCD monitor is on, the LCD ON signal at pin (7) set to high, and the DC/DC converter for the LCD monitor is turned on. 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.
ASIC,
memory
Power voltage
Power OFF
Power switch ON-
Auto power OFF
Shutter switch ON
CAMERA
Monitor OFF
LCD finder
Play back
Table 4-3. Camera Mode (Battery Operation)
Note) 4 MHz = Main clock operation, 32 kHz = Sub clock operation
3.3 V
OFF
OFF
ON
OFF
ON
ON
CCD
5 V (A)
+12 V etc.
OFF
OFF
ONOFF
OFF
ON
OFF
8 bit
CPU
3.2 V
(ALWAYS)
32KHz OFF
4 MHz OFF
4 MHz OFF
4 MHz OFF
4 MHz ON
4 MHz ON
MONITOR
+12V etc.
LCD
5V (L)
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