Memory Ic With Backup Battery; Nv-Ram - Sony DNW-A100 Maintenance Manual

1-2. Memory IC with Backup Battery

1-3. NV-RAM

1-2. Memory IC with Backup Battery
Memory IC (RAM) with backup battery is equipped on
IC710 of the SS-63 board.
This IC is used to store the setting data of setup menu, etc.
Besides it has an RTC (Real Time Clock) function, which
is also used in the VTR.
Owing to this battery, even if the external power is cut off,
this IC can maintain the stored data and the RTC continues
operating.
However, if the battery life comes to end with the external
power was cut off, memory can not maintain the stored
data and the RTC is failing to function.
Life of the backup battery
Life of the backup battery is guaranteed for at least ten
years in the absence of external power after this IC manu-
factured. Therefore, the replacement timing for IC710
varies depending on the operating condition (power-on
time).
Replacement time
When life-ending the battery while the VTR is powered
off, the RTC is failing to function.
If powered on in such a condition, the error code 96, sub
error message "CALENDAR CLOCK" will be displayed.
This message is displayed, be sure to replace IC710.
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. This sub error message is displayed on the video monitor
connected to the VIDEO OUTPUT COMPOSITE 3
(SUPER) connector with the CHARACTER switch
turned on.
Other sub error messages, if present, are also displayed
together.
. When the error code 96, sub error message "CALEN-
DAR CLOCK" is displayed, the date in the calendar will
be reset to 1/Nov./1996.
You can check the date in calendar/clock using the error
logger display mode (M2 : ERROR LOGGER) in the
maintenance mode.
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After replacing IC710, make/change settings of various
data and correct the calendar/clock.
Refer to "1-3. NV-RAM" for details.
1-2
1-3. NV-RAM
There are the NV-RAMs (EEP-ROM, and RAM with
backup battery) and EVR ICs used on the boards (includ-
ing optional boards) in the VTR. These devices store the
adjustment data, various setting data for the VTR, data for
the hours meters and error log respectively, etc.
EEP-ROM: Electric Erasable P-ROM
EVR: Electric Variable Resister (D/A converter with EEP-ROM)
After replacing above-mentioned device, take the follow-
ing service actions.
"Service action after replacing" and "Stored data" are
listed on next page.
IC710 on the SS-63 board is the only NV-RAM with
backup battery.
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After replacing the NV-RAM, NV-RAM error (error code
96, 97, or 98) will occur at power-on.
After replacing IC710/SS-63:
After replacing IC9/MS-50:
After replacing IC908/DM-89:
After replacing IC900/EQ-56:
After replacing IC200/TBC-23: Occurs Error code 98.
When replacing IC710 on the SS-63 board, NV-RAM error
(error code 96) will be occur once at the first power-on. At
the second power-on and later, this error will not occur.
Occurs Error code 96.
Occurs Error code 97.
Occurs Error code 98.
Occurs Error code 98.
DNW-A00/A50/A45
DNW-A100P/A50P/A45P