668-0003-C Rabbit Semiconductor, 668-0003-C Datasheet - Page 169

• Manufacturer Part Number: 668-0003-C
• Description: IC CPU RABBIT2000 30MHZ 100PQFP
• Manufacturer: Rabbit Semiconductor

Specifications of 668-0003-C

• Rohs Status: RoHS non-compliant
• Processor Type: Rabbit 2000 8-Bit
• Speed: 30MHz
• Voltage: 2.7V, 3V, 3.3V, 5V
• Mounting Type: Surface Mount
• Package / Case: 100-MQFP, 100-PQFP
• Features: -
• Other names: 316-1004; 668-0003

The 32.768 kHz clock oscillator and the associated real-time clock consume approxi-
mately 23 µA at 3 V. (At 2.25 V, when backed by a battery, the current consumption is
approximately 11 µA.) The (typical) current consumed when the main power is off, and
only the 32.768 kHz oscillator and clock are powered, is given by the formula
where V is the operating voltage. This is the current that must be supplied by a backup bat-
tery, not counting the current required by the associated circuits. The oscillator will not
operate below approximately 1.3 V. The measurement from which the above formula was
derived were made with a series resistor of 390 kΩ and load capacitors of 15 pF in the
32.768 kHz oscillator circuit. The shunt resistor was 10 MΩ.
If the processor is running at 32.768 kHz, then the added current to operate the processor
at room temperature (main oscillator shut off) is given by:
In low-power modes the current consumption is proportional to the square of the voltage.
At 3.0 V this is approximately 67 µA. Add the 25 µA needed to operate the oscillator and
the total current consumption will be approximately 92 µA with the processor operating at
32.768 kHz.
The current consumed by RAM or flash memory will be substantial and very significant at
lower frequencies if auto powerdown flash or low-power RAM is not used. If low-power
RAM is used to support the sleepy mode, the sleepy mode loop should be copied to RAM
and executed in RAM. When trying to operate in an ultra low-power sleepy mode, it is
important that no inputs be floating. Floating inputs consume substantial power. Keep in
mind that port D open-drain outputs will create floating inputs if not pulled toward zero.
Pullup resistors consume current and should be avoided or disabled in ultra low-power
modes. When testing a sleepy mode of operation, it is advisable to connect an ammeter to
make sure that no extra floating inputs or other current-consuming features are included in
the setup.
Chapter 15 AC Timing Specifications
current (µA) = 5.44*(V - 0.86)
current (µA) = 7.5*(V
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