mcf5272 Freescale Semiconductor, Inc, mcf5272 Datasheet - Page 499

• Manufacturer Part Number: mcf5272
• Description: Mcf5272 Coldfire Integrated Microprocessor User
• Manufacturer: Freescale Semiconductor, Inc

MOTOROLA
23.3 AC Electrical Specifications
23.3.1 Clock Input and Output Timing Specifications
Table 23-6 lists clock input and output timings.
Clock input and output timings listed in Table 23-6 are shown in Figure 23-1.
1
2
3
C1
C2
C3
C4
C4a
C4b
The clock period is referred to as T in the electrical specifications. The time for T is always in nS. Timing
specifications can be given in terms of T. For example, 2T+5 nS
Specification values are not tested.
Specification values listed are for maximum frequency of operation.
Name
2
2
3
3
Frequency of operation
CLKIN period (T)
CLKIN fall time (from V
CLKIN rise time (from V
CLKIN duty cycle (measured at 1.5 V)
CLKIN pulse width high (measured at 1.5 V)
CLKIN pulse width low (measured at 1.5 V)
AC timing specifications may be subject to change during
ongoing qualification.
AC timing specifications assume maximum output load
capacitance on all output pins including SDCLK. If this value
is different, the input and output timing specifications would
need to be adjusted to match the clock load.
AC timing specifications referenced to SDCLK assume
SDRAM control register bit 3 is 0. After reset this bit is set.
Table 23-6. Clock Input and Output Timing Specifications
CLKIN
(input)
C4a
Figure 23-1. Clock Input Timing Diagram
1
Chapter 23. Electrical Characteristics
h
l
Characteristic
= 2.4 V to V
= 0.5 V to V
C1
l
h
= 0.5 V)
= 2.4 V)
NOTE:
C2
C4b
6.75
6.75
Min
15
45
—
—
AC Electrical Specifications
0
0–66 MHz
V
V
h
l
66.00
Max
8.25
8.25
55
—
2
2
C3
MHz
Unit
nS
nS
nS
nS
nS
%
23-5