Datasheet

50
32099IS–01/2012
AT32UC3L016/32/64
Note: 1. V
VDD
corresponds to either V
VDDIN
or V
VDDIO
, depending on the supply for the pin. Refer to Section 3.2 on page 9 for details.
7.6 Oscillator Characteristics
7.6.1 Oscillator 0 (OSC0) Characteristics
7.6.1.1 Digital Clock Characteristics
The following table describes the characteristics for the oscillator when a digital clock is applied
on XIN.
7.6.1.2 Crystal Oscillator Characteristics
The following table describes the characteristics for the oscillator when a crystal is connected
between XIN and XOUT as shown in Figure 7-3. 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:
where C
PCB
is the capacitance of the PCB and C
i
is the internal equivalent load capacitance.
t
FALL
Fall time
Cbus = 400pF, V
VDD
> 2.0V 250
ns
Cbus = 400pF, V
VDD
> 1.62V 470
f
MAX
Max frequency Cbus = 400pF, V
VDD
> 2.0V 400 kHz
Table 7-10. TWI Pin Characteristics
(1)
Symbol Parameter Condition Min Typ Max Units
Table 7-11. Digital Clock Characteristics
Symbol Parameter Conditions Min Typ Max Units
f
CPXIN
XIN clock frequency 50 MHz
t
CPXIN
XIN clock duty cycle 40 60 %
t
STARTUP
Startup time 0 cycles
C
IN
XIN input capacitance
TQFP48 package 7.0
pFQFN48 package 6.7
TLLGA48 package 6.7
C
LEXT
2C
L
C
i
–()C
PCB
–=
Table 7-12. Crystal Oscillator Characteristics
Symbol Parameter Conditions Min Typ Max Unit
f
OUT
Crystal oscillator frequency 0.45 10 16 MHz
C
L
Crystal load capacitance 6 18
pF
C
i
Internal equivalent load capacitance 2