Preliminary
S3C2451X RISC MICROPROCESSOR
SYSTEM CONTROLLER
2-7
Preliminary product information describe products that are in development,
for which full characterization data and associated errata are not yet available.
Specifications and information herein are subject to change without notice.
Table 2-3. Clock source selection for the EPLL
CLKSRC[8] (register)
CLKSRC[7] (register)
OM[0]
EPLL Reference Clock
0
X
0 XTI
0
X
1 EXTCLK
1
0 X XTI
1
1 X
EXTCLK
Table 2-4. PLL & Clock Generator condition
MPLLCAP : N/A
Loop filter capacitance
C
LF
EPLLCAP :Typical 1.8nF 5%
Fin
-
MPLL: 10 – 30 MHz
EPLL: 10 – 40 MHz
Fout
-
MPLL: 40 – 1600 MHz
EPLL: 20 – 600 MHz
External capacitance used for X-tal
C
EXT
15
pF
Feedback Resistor used for X-tal
R
F
1Mohm
Figure 2-4. Main Oscillator circuit examples