647
6242E–ATARM–11-Sep09
AT91SAM9261S
39.5.3
Main Oscillator Characteristics
Notes:
1. C
S is the shunt capacitance.
2. RS = 100 to 200 Ω ; CS = 2.0 to 2.5 pF; CM = 2 to 1.5 fF (typ, worst case) using 1 kΩ serial resistor on XOUT.
3. R
S = 50 to 100 Ω ; CS = 2.0 to 2.5 pF; CM = 4 to 3 fF (typ, worst case).
4. R
S = 25 to 50 Ω ; CS = 2.5 to 3.0 pF; CM = 7 to 5 fF (typ, worst case).
5. RS = 20 to 50 Ω ; CS = 3.2 to 4.0 pF; CM = 10 to 8 fF (typ, worst case).
6. Additional user load capacitance should be subtracted from C
LEXT.
7. C
LEXT is determined by taking into account internal parasitic and package load capacitance.
Table 39-10. Main Oscillator Characteristics
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
1/(tCPMAIN)
Crystal Oscillator Frequency
3
16
20
MHz
C
CRYSTAL
Crystal Load Capacitance
12.5
15
17.5
pF
External Load Capacitance
CCRYSTAL = 12.5 pF
15
pF
18
C
CRYSTAL = 17.5 pF
22
Duty Cycle
40
50
60
%
t
ST
Startup Time
VDDPLL = 3 to 3.6V
CPMAIN) = 3 MHz
C
CPMAIN) = 8 MHz
CPMAIN) = 16 MHz
CPMAIN) = 20 MHz
20
4
2
ms
IDDST
Standby Current Consumption
Standby mode
1
A
P
ON
Drive Level
@ 3 MHz
15
W
@ 8 MHz
30
@ 16 MHz
50
@ 20 MHz
50
IDD ON
Current Dissipation
150
250
A
300
530
300
530
450
650
XIN
XOUT
CLEXT
CCRYSTAL
AT91SAM9261S