SANYO VPC-J1EX, VPC-J1 STROBE CIRCUIT DESCRIPTION

1-4. ST1 STROBE CIRCUIT DESCRIPTION

1. Charging Circuit

When UNREG power is supplied to the charge circuit and the
CHG signal from microprocessor 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, Q5407 turns ON and
the charging circuit starts operating.

1-2. Power supply filter

C5401 constitutes 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 C5512.

1-6. Voltage monitoring circuit

This circuit is used to maintain the voltage accumulated at
C5512 at a constance level.
After the charging voltage is divided and converted to a lower
voltage by R5417, R5419 and R5420, it is output to the mi­croprocessor as the monitoring voltage VMONIT. When this
VMONIT voltage reaches a specified level at the micropro­cessor, the CHG signal is switched to Low and charging is
interrupted.

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1-5. SYA CIRCUIT DESCRIPTION

1. Configuration and Functions

For the overall configuration of the SYA block, refer to the block diagram. The SYA block 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

1~3

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 0~3

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

/STBY_LED (GREEN)

Signal

/SCAN OUT 0~2

/SCAN OUT 3

P ON

PA ON

/STILL_LED

/CSTILL_LED

VSS

VDD

/MOVIE_LED

/STBY_LED (RED)

/AVREF_ON

SI

SO

SCK

PRG SI

PRG SO

PRG SCK

LCD_ON

BLON

CHG ON

INT_TEMP

NOT USED

CHG VOL

BATTERY

AVREF

AVDD

/RESET

XCOUT

XCIN

IC

XOUT

XIN

VSS

/BAT OFF

/SREQ

/SCAN IN6

CLOSE

/DC_IN

I/O

O

O

O

O

O

O

O

O

O

O

O

I/O

O

I/O

O

O

O

O

O

Outline

Key scan output

Lens barrier open/close detection switch for scan output

Digital power ON/OFF control H : ON

Analog power ON/OFF control H : ON

Still image mode LED (orange) control L : ON

Video clip mode LED (orange) control L : ON

-

-

I

I

-

-

I

I

-

I

I

-

-

I

I

I

I

-

I

I

I

I

I

GND

VDD

Video clip mode LED (orange) 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 writing receiving data

Flash memory writing sending data

Flash memory writing communication clock

LCD power ON/OFF control 1 H : ON

LCD backlight ON/OFF control H : ON

Flash charge control H : ON

VDD

AVSS

Key scan input

Internal temperature 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 (37.768 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)

Key scan input 6

Lens barrier close detection switch input

DC jack/battery detection input

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