20-668-0011 Rabbit Semiconductor, 20-668-0011 Datasheet - Page 21

• Manufacturer Part Number: 20-668-0011
• Description: IC MPU RABIT3000A 55.5MHZ128LQFP
• Manufacturer: Rabbit Semiconductor

Specifications of 20-668-0011

• 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
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 55.5 MHz
• Operating Supply Voltage: 1.8 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 55 C
• Number Of Programmable I/os: 56
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 316-1061

2.3.2 Spectrum Spreader
When enabled, the spectrum spreader stretches and compresses the main clock in a complex
pattern that spreads the energy of the clock harmonics over a wider range of frequencies.
There are three settings that correspond to normal and strong spreading in the 0–50 MHz
and >50 MHz main clock range. Each setting will affect the clock cycle differently; the
maximum cycle shortening (at 1.8 V and 25°C) is shown in Table 2-2 below.
Chapter 2 Clocks
0–50 MHz
Normal
Strong
—
> 50 MHz
Normal
Strong
—
Table 2-2. Spectrum Spreader Settings
Figure 2-1. Effects of Spectrum Spreader
GCM0R
0x0040
0x0000
0x0080
Value
Normal spreading of frequencies over
50 MHz
Normal spreading of frequencies up to
50 MHz; strong spreading of
frequencies over 50 MHz
Strong spreading of frequencies up to
50 MHz; normal spreading of
frequencies over 50 MHz
Description
Shortening
Max. Cycle
2.3 ns
4.5 ns
3 ns
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