668-0010 Rabbit Semiconductor, 668-0010 Datasheet - Page 255

• Manufacturer Part Number: 668-0010
• Description: IC MPU RABIT3000 55.5MHZ 128LQFP
• Manufacturer: Rabbit Semiconductor

Specifications of 668-0010

• Rohs Status: RoHS non-compliant
• Processor Type: Rabbit 3000 8-Bit
• Speed: 55.5MHz
• Voltage: 2.5V, 2.7V, 3V, 3.3V
• Mounting Type: Surface Mount
• Package / Case: 128-LQFP
• Features: -
• Other names: 316-1016

27.4 Clock Speeds
27.4.1 Recommended Clock/Memory Configurations
The preferred configuration for a Rabbit-based system is to use an external crystal or reso-
nator that has a frequency one-half of the maximum internal clock frequency. The oscillator
frequency can be doubled or divided by 2, 4, 6, or 8, giving a variety of operating speeds
from the same crystal frequency. In addition, the 32.768 kHz oscillator that drives the
battery-backable clock can be used as the main processor clock and, to save the substantial
power consumed by the fast oscillator, the fast oscillator can be turned off. This scenario is
called the sleepy mode, where the clock speed is from 2 kHz to 32 kHz, and the operating
system current consumption of 10 to 120 µA depends on frequency and voltage.
Table 27-10 describes some recommended clock and memory configurations for 8-bit
memory devices. Optimal configurations for using 15 ns, 45–55 ns, and 70 ns memories
are shown.
The Rabbit 3000 is rated for a minimum clock period of 16 ns for both commercial and
industrial specifications (preliminary). The commercial rating calls for a ±5% voltage
variation from 3.3 V, and a temperature range from -40 to + 70°C. The industrial ratings
stretch the voltage variation to ±10% over a temperature range from -55 to + 85°C. This
corresponds to maximum clock frequencies of about 58.8 MHz (industrial). If the clock
doubler or spectrum spreader is used, these maximum ratings must be reduced as shown in
Table 27-11.
Chapter 27 Specifications
Frequency
29.4912
22.1184
14.7456
11.0592
(MHz)
Input
Frequency
Table 27-10. Recommended Clock/Memory Configurations
Internal
58.9824
44.2368
29.4912
22.1184
(MHz)
8 bits, 45–55 ns,
Recommended Memory Setup
8 bits, 15 ns,
8 bits, 15 ns,
8 bits, 70 ns,
0 wait states
0 wait states
0 wait states
0 wait states
SRAM
8 bits, 45–55 ns,
8 bits, 45–55 ns,
8 bits, 45–55 ns,
8 bits, 70 ns,
2 wait states
0 wait states
0 wait states
1 wait state
Flash
Fastest 8-bit configuration
without wait states
(run code from SRAM)
Fastest 8-bit, 55 ns configuration
with 1 wait state
(run code in SRAM)
Fastest 8-bit, 55 ns configuration
without wait states
Fastest 8-bit, 70 ns configuration
without wait states
Use
245