Datasheet

 2017 Microchip Technology Inc. DS60001516A-page 743
SAM9G20
40.5 Crystal Oscillator Characteristics
The following characteristics are applicable to the operating temperature range: T
A
= -40°C to 85°C and worst case of power supply, unless
otherwise specified.
40.5.1 32 kHz Oscillator Characteristics
Note 1: R
S
is the equivalent series resistance.
2: C
LEXT32
is determined by taking into account internal, parasitic and package load capacitance.
Figure 40-2: 32 kHz Oscillator Schematic
Table 40-10: 32 kHz Oscillator Characteristics
Symbol Parameter Conditions Min Typ Max Unit
1/(t
CP32KHz
) Crystal Oscillator Frequency – 32.768 – kHz
C
CRYSTAL32
Load Capacitance Crystal @ 32.768 kHz 6 – 12.5 pF
C
LEXT32
(2)
External Load Capacitance
C
CRYSTAL32
= 6 pF – 6 – pF
C
CRYSTAL32
= 12.5 pF – 19 – pF
Duty Cycle 40 – 60 %
t
START
Startup Time
V
DDBU
= 1.0V,
R
S
= 50 kΩ
(1)
C
CRYSTAL32
= 6 pF – – 300 ms
C
CRYSTAL32
= 12.5
pF
––900ms
V
DDBU
= 1.0V
R
S
= 100 kΩ
(1)
C
CRYSTAL32
= 6 pF – – 600 ms
C
CRYSTAL32
= 12.5
pF
– – 1200 ms
XIN32 XOUT32 GNDBU
C
LEXT32
C
LEXT32
C
CRYSTAL32
SAM92G20