SC2200 NSC [National Semiconductor], SC2200 Datasheet - Page 93

• Manufacturer Part Number: SC2200
• Description: Thin Client On a Chip
• Manufacturer: NSC [National Semiconductor]

Revision 3.0
General Configuration Block
3.5
This section describes the registers for the clocks required
by the GX1 module, Core Logic module, and the Video
Processor, and how these clocks are generated. See Fig-
ure 3-2 for a clock generation diagram.
Note:
CLOCK GENERATORS AND PLLS
V
PLL2
32.768 KHz
Oscillator
Oscillator
27 MHz
Crystal
Crystal
powers PLL2 and PLL5. V
32.768 KHz
DISABLE
Shutdown
Shutdown
Shutdown
Shutdown
Shutdown
Shutdown
Shutdown
Figure 3-2. Clock Generation Block Diagram
(ACPI)
(ACPI)
(Continued)
PLL3
CLK
powers PLL3, PLL4, and PLL6.
100-333 MHz
57.273 MHz
25-135 MHz
24.576 MHz
66.67 MHz
48 MHz
Divider
PLL6
PLL2
PLL5
PLL4
PLL3
ADL
Divide
by 2
93
The clock generators are based on 32.768 KHz and 27.000
MHz crystal oscillators. The 32.768 KHz crystal oscillator is
described in Section 4.5.2 "RTC Clock Generation" on
page 114 (functional description of the RTC).
Divide
66 MHz
by 4
33 MHz
48 MHz
ACPI Clock (14.318 MHz)
Real-Time Clock (RTC)
High-Resolution Timer Clock
USB Clock (48 MHz)
and I/O Block Clock
Internal Fast-PCI Clock
(24.576 MHz)
AC97_CLK
DISABLE
External PCI Clock
DISABLE
SDRAM Clock
Core Clock
(33.3 MHz)
Dot Clock
CLK27M Ball
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