LM3S2776 Datasheet, PDF (725/785 Pages) Texas Instruments – Stellaris® LM3S2776 Microcontroller

Stellaris® LM3S2776 Microcontroller
Table 21-10. Clock Characteristics (continued)
Parameter Parameter Name
Min
Nom
Max
f_MOSC
Main oscillator frequency
1
-
16.384
t_{MOSC_per}
Main oscillator period
61
-
1000
f_{ref_crystal_bypass}
Crystal reference using the main oscillator
(PLL in BYPASS mode)^a
1
-
16.384
f_{ref_ext_bypass}
External clock reference (PLL in BYPASS
0
mode)^a
-
50
f_{system_clock}
System clock
0
-
50
a. The ADC must be clocked from the PLL or directly from a 16-MHz clock source to operate properly.
Unit
MHz
ns
MHz
MHz
MHz
Table 21-11. Crystal Characteristics
Parameter Name
Frequency
Frequency tolerance
Aging
Oscillation mode
Temperature stability (-40°C to
85°C)
Motional capacitance (typ)
Motional inductance (typ)
Equivalent series resistance
(max)
Shunt capacitance (max)
Load capacitance (typ)
Drive level (typ)
16
±50
±5
Parallel
±25
13.9
7.15
80
10
16
100
12
±50
±5
Parallel
±25
18.5
9.5
100
10
16
100
Value
8
6
±50
±50
±5
±5
Parallel Parallel
±25
±25
27.8
37.0
14.3
19.1
120
160
10
10
16
16
100
100
4
±50
±5
Parallel
±25
55.6
28.6
200
10
16
100
3.5
±50
±5
Parallel
±25
Units
MHz
ppm
ppm/yr
-
ppm
63.5
pF
32.7
mH
220
Ω
10
pF
16
pF
100
µW
21.2.2.1 System Clock Specifications with ADC Operation
Table 21-12. System Clock Characteristics with ADC Operation
Parameter Parameter Name
Min
f_sysadc
System clock frequency when the ADC module is
16
operating (when PLL is bypassed)
Nom
Max
-
-
Unit
MHz
21.2.3 JTAG and Boundary Scan
Table 21-13. JTAG Characteristics
Parameter
No.
J1
J2
J3
J4
J5
J6
J7
Parameter Parameter Name
f_TCK
t_TCK
t_{TCK_LOW}
t_{TCK_HIGH}
t_{TCK_R}
t_{TCK_F}
t_{TMS_SU}
TCK operational clock frequency
TCK operational clock period
TCK clock Low time
TCK clock High time
TCK rise time
TCK fall time
TMS setup time to TCK rise
Min
Nom
0
-
100
-
-
t_TCK/2
-
t_TCK/2
0
-
0
-
20
-
Max
10
-
-
-
10
10
-
Unit
MHz
ns
ns
ns
ns
ns
ns
November 17, 2011
725
Texas Instruments-Production Data