Note:
1. These values are based on characterization.
45.12.2. XOSC32K
45.12.2.1. Digital Clock Characteristics
The following table describes the characteristics for the oscillator when a digital clock is applied on Xin32
pin.
Table 45-38. Digital Clock Characteristics
(1)
Symbol
Parameter
Min.
Typ.
Max.
Units
f
CPXIN32
Xin32 clock frequency
-
32.768
1000
kHz
DC
xin
Xin32 clock duty cycle
40
50
60
%
Note:
These values are based on simulation. They are not covered by production test limits or
characterization.
45.12.2.2. External 32KHz Crystal Oscillator (XOSC32K) Characteristics
The following table describes the characteristics for the oscillator when a crystal is connected between
XIN32 and XOUT32.
Figure 45-3. Oscillator Connection
C
SHUNT
L
M
R
M
C
M
C
STRAY
C
LEXT
C
LEXT
Xin32
Crystal
Xout32
The user must choose a crystal oscillator where the crystal load capacitance C
L
is within the range given
in the table. The exact value of C
L
can be found in the crystal datasheet. The capacitance of the external
capacitors (C
LEXT
) can then be computed as follows:
C
LEXT
= 2 C
L
− C
STRAY
− C
SHUNT
where C
STRAY
is the capacitance of the pins and PCB, C
SHUNT
is the shunt capacitance of the crystal.
Table 45-39. 32KHz Crystal Oscillator Electrical Characteristics
Symbol
Parameter
Conditions
Min.
Typ.
Max.
Units
FOUT
Crystal oscillator frequency
-
-
32.768
-
kHz
CL
Crystal load capacitance
-
7
9
12.5
pF
Atmel SAM L22G / L22J / L22N [DATASHEET]
Atmel-42402E-SAM L22G / L22J / L22N_Datasheet_Complete-07/2016
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