Nonswitching electrical specifications
2. VDD = 3 V, TA = 25 °C, fOSC = 32 kHz (crystal), fBUS = 24 MHz
3. Specified according to Annex D of IEC Standard 61967-2, Measurement of Radiated Emissions—TEM Cell and Wideband
TEM Cell Method.
5.2.7 Designing with radiated emissions in mind
To find application notes that provide guidance on designing your system to minimize
interference from radiated emissions:
1. Go to http://www.freescale.com.
2. Perform a keyword search for “EMC design.”
5.2.8 Capacitance attributes
Table 7. Capacitance attributes
Symbol
Description
Min.
Max.
Unit
CIN_A
Input capacitance: analog pins
—
7
pF
CIN_D
Input capacitance: digital pins
—
7
pF
5.3 Switching electrical specifications
Table 8. Device clock specifications
Symbol
Description
Min.
Max.
Unit
Notes
Normal run mode
fSYS
fSYS_USB
fBUS
System and core clock
—
20
—
—
—
50
—
25
25
25
MHz
MHz
MHz
MHz
MHz
System and core clock when USB in operation
Bus clock
FB_CLK
fLPTMR
Mini-FlexBus clock
LPTMR clock
1
1
VLPR mode
fSYS
fBUS
System and core clock
Bus clock
—
—
—
—
2
1
MHz
MHz
MHz
MHz
FB_CLK
fLPTMR
Mini-FlexBus clock
LPTMR clock2
1
25
1. When the Mini-FlexBus is enabled, its clock frequency is always the same as the bus clock frequency.
2. A maximum frequency of 25 MHz for the LPTMR in VLPR mode is possible when the LPTMR is configured for pulse
counting mode and is driven externally via the LPTMR_ALT1, LPTMR_ALT2, or LPTMR_ALT3 pin.
MCF51JU128 Data Sheet, Rev. 4, 01/2012.
18
Freescale Semiconductor, Inc.
FREESCALE [ Freescale ]
