DOWNLOAD Sony DSC-F1 (serv.man2) Service Manual ↓ Size: 330.5 KB | Pages: 43 in PDF or view online for FREE

— 13 —

The lithium ion rechargeable battery is automatically charged when the following conditions are satisfied.

• When the HI microprocessor is started
• When the AC adapter is connected (when the UNREG voltage is higher than 5.2V)

(Detected by the C332 voltage of the HV board)

• When the lithium ion rechargeable battery is connected

(Detected by Pin @§ of IC301 of the HV board)

• When the function dial is OFF

(Detected by the MODE SW Pin @º of IC301)

The instruction manual describes that “to charge, switch the function dial to camera or playback once, and then set it back

to OFF again”.

However, if the above conditions are satisfied, the battery will be charged automatically even if the function dial is not

rotated.

Only when the HI microprocessor is reset, it will be necessary to rotate the function dial to start the microprocessor.
(when the unit is not operated for a long period of time, when the reset button is pressed, etc.)

The charging time is approximately 8 hours at the maximum and the charging current is approximately 750 mA. These

values are varied according to the remaining power of the rechargeable battery.

Charging consists of normal charging and trickle charging. If the rechargeable battery voltage has dropped excessively due

to long term storage, first trickle charging is performed, and then normal charging is performed when the voltage recovers to
a certain extent.

The HI microprocessor is incorporated in the charging timer, and normal charging completes after 6 hours. However, if the

rechargeable battery voltage was dropped considerable due to long term storage, trickle charging is performed first for about
one hour. Therefore charging may be performed up to 8 hours in some cases.

The LED will continue being lit for 6 hours by the charging timer even if the rechargeable battery has been fully charged.

In addition, if the shutter button is pressed during charging, the charging timer of the HI microprocessor will be reset. In this
case, the charging lamp may not go off for more than 8 hours.

When the AC plug is connected when the chargeable batteries are loaded, Q317 of the HV board is turned ON by the

voltage of the minus side terminal of the chargeable batteries (LI BATT), the wake up signal will be input to the XWP
terminal (Pin &ª of IC301) of the HI microprocessor.

The charging conditions are checked, and if the batteries can be charged, charging is started.

When the LICHGON signal (Pin !¡ of IC301) of the HI microprocessor becomes H, Q006 and Q005 of the DD board turn

ON, and the UNREG voltage is supplied to the charging circuit. When Pin 2 of the PWM controller (IC001) for charging
becomes L, IC001 is started.

A voltage lower than UNREG by 2.5V is output to Pin 3 of the comparator (IC002) by IC003. (Approximately 3.5V

during charging).

The output of Pin 4 of IC002 which is obtained by comparing this reference voltage and the battery feedback voltage input

to Pin 1 of IC002 is input to Pin 8 of IC001 (Approximately 0.6V during charging).

The PWM signal is output from Pin 5 of the PWM controller (IC001) by the input voltage, switched by Q003, and the

charging current flows to the rechargeable battery.

When there is little power remaining in the rechargeable battery, the R001 voltage rises when excessive current flows. As

a result, Q004 turns ON, and the potential of the minus side of the rechargeable battery is raised to restrict the charging
current. The charging current is approximately 750 mA.

— 14 —

When the voltage between the terminals becomes too low due to storage over a long period of time, trickle charging is

performed.

Q001 of the DD board is turned ON by the H output of the XLCURRCHG signal (Pin ^∞ of IC301) of the HI microprocessor,

the trickle charging current flows to R142, etc.

At this time, the LICHGON signal (Pin !¡ of IC301) becomes a L output, and the normal charging circuit will not operate.
When the terminal voltage of the rechargeable battery reaches a certain value, the normal charging starts.

After the normal charging mode is set and six hours have passed, charging stops.
When the terminal voltage of the rechargeable battery reaches a constant value, the LICHGON signal of the HI

microprocessor is set to L to stop charging.

— 15 —

When the function dial of the DSC-F1 is set to “Camera A” or “Camera M”, images shot by the camera are displayed on

the LCD screen. These operations are described in the following simply.
(Refer to Fig. 4.)

• Inputting images

Image data is input every 1/30 seconds by the CCD and output.
The image data is A/D converted to the digital data, and written in the 4 Mbit memory after camera signal processing.

• Image correction

During the auto mode, the shutter speed, iris, etc. are automatically corrected by the camera microprocessor according to

the image data input by the AE/AWB detector.

During the manual mode, the shutter speed, etc. are set to the values set by the menu function by the camera

microprocessor.

In manual settings such as the shutter speed, key inputs are detected by the HI microprocessor, and values of the camera

microprocessor are changed by the main microprocessor. These communications are performed using serial data.

• Generation of video signal, LCD display

Data written in the 4 Mbit memory is immediately read, converted to the NTSC/PAL signal, and further converted to the

Y/C signal. This Y/C signal is analog-processed, and output from the video output terminal. The Y/C signal is also converted
to the RGB signal to display images on the LCD.

— 16 —