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XC2238M Datasheet, PDF (81/102 Pages) Infineon Technologies AG – 16/32-Bit Single-Chip Microcontroller with 32-Bit Performance XC2000 Family Derivatives / Base Line
XC2238M, XC2239M
XC2000 Family Derivatives / Base Line
Electrical Parameters
4.6.2 Definition of Internal Timing
The internal operation of the XC223xM is controlled by the internal system clock fSYS.
Because the system clock signal fSYS can be generated from a number of internal and
external sources using different mechanisms, the duration of the system clock periods
(TCSs) and their variation (as well as the derived external timing) depend on the
mechanism used to generate fSYS. This must be considered when calculating the timing
for the XC223xM.
Phase Locked Loop Operation (1:N)
fIN
fSYS
Direct Clock Drive (1:1)
fIN
TCS
fSYS
Prescaler Operation (N:1)
fIN
TCS
fSYS
TCS
M C_XC2X_CLOCKGEN
Figure 18 Generation Mechanisms for the System Clock
Note: The example of PLL operation shown in Figure 18 uses a PLL factor of 1:4; the
example of prescaler operation uses a divider factor of 2:1.
The specification of the external timing (AC Characteristics) depends on the period of the
system clock (TCS).
Data Sheet
81
V2.0, 2009-03