101-0399 Rabbit Semiconductor, 101-0399 Datasheet - Page 68

• Manufacturer Part Number: 101-0399
• Description: KIT DEV RABBIT RCM2000 INT'L
• Manufacturer: Rabbit Semiconductor
• Series: RabbitCore 2000r
• Type: MPU Moduler

Specifications of 101-0399

• Contents: RabbitCore Module, Dev. Board, AC Adapter, Cable and Dynamic C® CD-Rom
• For Use With/related Products: RCM2000, RCM2010, RCM2020
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 101-399; 101-399

The drain on the battery by the RCM2000 is typically 10 µA when no other power is sup-
plied. If a 950 mA·h battery is used, the battery can last more than 6 years:
Since the shelf life of the battery is 10 years, the battery can last for its full shelf life. The
actual life in your application will depend on the current drawn by components not on the
RCM2000 and the storage capacity of the battery.
C.1.2 Battery-Backup Circuit
The battery-backup circuit serves three purposes:
• It reduces the battery voltage to the SRAM and to the real-time clock, thereby limiting
• It ensures that current can flow only out of the battery to prevent charging the battery.
• A voltage, VOSC, is supplied to U5, which keeps the 32.768 kHz oscillator working
VRAM and Vcc are nearly equal (<100 mV, typically 10 mV) when power is supplied to
the RCM2000.
Figure C-2 shows the RCM2000 battery-backup circuit.
VRAM is also available on pin 34 of header J2 to facilitate battery backup of the external
circuit. Note that the recommended minimum resistive load at VRAM is 100 kΩ, and new
battery life calculations should be done to take external loading into account.
64
the current consumed by the real-time clock and lengthening the battery life.
when the voltage begins to drop.
950 mA·h
----------------------- -
10 µA
Figure C-2. RCM2000 Battery-Backup Circuit
m
=
10.8 years (shelf life = 10 years).
W
W
thermistor
W
W
W
W
RabbitCore RCM2000