101-1006 Rabbit Semiconductor, 101-1006 Datasheet - Page 216

• Manufacturer Part Number: 101-1006
• Description: MODULE POWERCORE FLEX 3800
• Manufacturer: Rabbit Semiconductor

Specifications of 101-1006

• Module/board Type: MPU Core Module
• For Use With/related Products: RCM3800
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

D.2 Battery-Backup Circuits
The data SRAM and the real-time clock on the PowerCore module have battery backup.
Power to the SRAM and the real-time clock (VRAM) is provided by two different sources,
depending on whether the PowerCore module is powered or not. When the PowerCore
module is powered normally, and the +5 V supply is within operating limits, the SRAM and
the real-time clock are powered from the +5 V supply. If power to the board is lost or falls
below 4.38 V, the VRAM and real-time clock power will come from the battery. The reset
generator circuit controls the source of power by way of its
A replaceable 220 mA·h lithium battery provides power to the real-time clock and SRAM
when external power is removed from the circuit board. The drain on the battery is typically
less than 6 µA when there is no external power applied to the PowerCore module, and so the
expected shelf life of the battery is
The actual life in your application will depend on the current drawn by components not on
the PowerCore module and the storage capacity of the battery. The PowerCore module
does not drain the battery while it is powered up normally.
Cycle the main power off/on on the PowerCore module after you install a backup battery
for the first time, and whenever you replace the battery. This step will minimize the cur-
rent drawn by the real-time clock oscillator circuit from the backup battery should the
PowerCore module experience a loss of main power.
D.2.1 Replacing the Backup Battery
The battery is user-replaceable, and is fitted in a battery holder. To replace the battery,
slide out the old battery. Use only a 2032 or equivalent replacement lithium battery, and
insert it into the battery holder with the + side facing away from the PowerCore module.
208
NOTE: The SRAM contents and the real-time clock settings will be lost if the battery is
220 mA·h
----------------------- -
replaced with no power applied to the PowerCore module. Exercise care if you replace
the battery while external power is applied to the PowerCore module.
CAUTION: Be careful when replacing the battery with external AC power applied
to the PowerCore module. AC voltages up to 60 V may be present on locking con-
nector J3.
CAUTION: There is an explosion danger if the battery is short-circuited, recharged,
or replaced incorrectly. Replace the battery only with the same type or an equivalent
type recommended by the battery manufacturer. Dispose of used batteries according
to the battery manufacturer’s instructions.
6 µA
=
4.2 years.
/RESET
output signal.
PowerCore FLEX