
622
6222H–ATARM–25-Jan-12
SAM7SE512/256/32
40.4.2
Main Oscillator Characteristics
Notes:
1. C
S is the shunt capacitance.
2. R
S = 100-200 Ω; CSHUNT = 2.0 - 2.5 pF; CM = 2 – 1.5 fF (typ, worst case) using 1 K ohm serial resistor on xout.
3. RS = 50-100 Ω;
CSHUNT = 2.0 - 2.5 pF; CM = 4 - 3 fF (typ, worst case).
4. R
S = 25-50 Ω; CSHUNT = 2.5 - 3.0 pF; CM = 7 -5 fF (typ, worst case).
5. R
S = 20-50 Ω; CSHUNT = 3.2 - 4.0 pF; CM = 10 - 8 fF (typ, worst case).
6. CL and CLEXT
Table 40-10. Main Oscillator Characteristics
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
1/(tCPMAIN)
Crystal Oscillator Frequency
3
16
20
MHz
CL1, CL2
SAM7SE512/256
Internal Load Capacitance (C
L1 = CL2)
Integrated Load Capacitance
((XIN or XOUT))
34
40
46
pF
CL1, CL2
SAM7SE32
Internal Load Capacitance (C
L1 = CL2)
Integrated Load Capacitance
(XIN or XOUT)
18
22
26
pF
CL
SAM7SE512/256
Equivalent Load Capacitance
Integrated Load Capacitance
(XIN and XOUT in series)
17
20
23
pF
CL
SAM7SE32
Equivalent Load Capacitance
Integrated Load Capacitance
(XIN and XOUT in series)
911
13
pF
Duty Cycle
30
50
70
%
tST
Startup Time
VDDPLL = 1.2 to 2V
C
CPMAIN) = 3 MHz
CPMAIN) = 16 MHz
CPMAIN) = 20 MHz
14.5
1.4
1
ms
IDDST
Standby Current Consumption
Standby mode
1
A
P
ON
Drive level
@3 MHz
@8 MHz
@16 MHz
@20 MHz
15
30
50
W
IDD ON
Current dissipation
150
300
400
250
450
550
A
CLEXT
Maximum external capacitor
on XIN and XOUT
10
pF
XIN
XOUT
CLEXT
CL
CLEXT
AT91SAM7SE