SANYO VPC-MZ3EX, VPC-MZ3, VPC-MZ3GX, VAR-G6U, VAR-G6EX 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 SY1 board 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.

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 C5412.

1-6. Voltage monitoring circuit

This circuit is used to maintain the voltage accumulated at C5412 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 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.

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.

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1-5. 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	Signal	I/O	Outline
1~4	SCAN OUT 0~3	O	Key matrix output
5	P ON	O	Digital power ON/OFF control	H : ON
6	PA ON	O	Analog power ON/OFF control	H : ON
7	LCD ON	O	LCD power ON/OFF control	H : ON
8	BL_ON	O	LCD backlight ON/OFF
9	VSS	-	GND
10	VDD	-	VDD
11	SELF_LED	O	Self-timer LED control	L : ON
12	STBY_LED (GREEN)	O	Stand-by LED (green) control	L : ON
13	STBY_LED (RED)	O	Stand-by LED (red) control	L : ON
14	AVREF_ON	O	A/D converter standard voltage control	L : ON
15	SI	I	Receiving data (from ASIC)
16	SO	O	Sending data (to ASIC)
17	SCK	I/O	Communication clock (to ASIC)
18	PRG SI	I	Flash memory write receiving data
19	PRG SO	O	Flash memory write sending data
20	PRG SCK	I/O	Flash memory write communication clock
21	NOT USED	-	-
22	NOT USED	-	-
23	CHG ON	O	Flash charge control	H : ON
24	VDD	-	VDD
25	AVSS	-	Analog GND
26~29	SCAN IN 3~0	I	Key scan input
30	INT_TMP	I	Internal temperature detection input (analog input)
31	NOT USED	-	-
32	CHG VOL	I	Storobe charge voltage detection (analog input)
33	BATTERY	I	Battery voltage detection (analog input)
34	AVREF	-	Analog standard voltage input terminal
35	AVDD	-	A/D converter analog power terminal
36	RESET	I	Reset input
37	XCOUT	O	Clock oscillation terminal (32.768 kHz)
38	XCIN	I	Clock oscillation terminal
39	IC	I	Flash memory writing voltage
40	XOUT	O	Main clock oscillation terminal (4MHz)
41	XIN	I	Main clock oscillation terminal
42	VSS	-	GND
43	BAT OFF	I	Battery OFF detection
44	SREQ	I	Serial communication requirement (from ASIC)
45	SCAN IN6	I	Key scan input 6
46	INTP3	I	-
47	NOT USED	-	-
48	BOOT	I/O	Compulsion boot control

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