at91sam9g20-cu ATMEL Corporation, at91sam9g20-cu Datasheet - Page 766

• Manufacturer Part Number: at91sam9g20-cu
• Description: At91 Arm Thumb Microcontrollers
• Manufacturer: ATMEL Corporation

41.5.3
Table 41-11. RC Oscillator Characteristics
41.5.4
766
Symbol
1/(t
t
ST
CPRCz
)
AT91SAM9G20 Preliminary
RC Oscillator Characteristics
Slow Clock Selection
Parameter
Crystal Oscillator Frequency
Duty Cycle
Startup Time
Table 41-12
Table 41-12. Slow Clock Selection
The startup counter delay for the slow clock oscillator depends on the OSCSEL signal. The
32,768 Hz startup delay is 1200 ms whereas it is 150 µs for the internal RC oscillator (refer to
Table
the device.
OSCSEL
0
1
41-12). The pin OSCSEL must be tied either to GND or VDDBU for correct operation of
defines the states for OSCSEL signal.
Conditions
Slow Clock
Internal RC
External 32768Hz
Startup Time (Max)
150 µs
1200 ms
Min
20
45
Typ
32
6384B–ATARM–15-Dec-08
Max
44
55
75
Unit
kHz
µs
%