atmega3250v-8auatmega325v-8ai ATMEL Corporation, atmega3250v-8auatmega325v-8ai Datasheet - Page 43

• Manufacturer Part Number: atmega3250v-8auatmega325v-8ai
• Description: Atmega3250 8-bit Microcontroller With In-system Programmable Flash
• Manufacturer: ATMEL Corporation

11.6
11.7
11.7.1
2570L–AVR–08/07
Watchdog Reset
Internal Voltage Reference
Voltage Reference Enable Signals and Start-up Time
Figure 11-5. Brown-out Reset During Operation
When the Watchdog times out, it will generate a short reset pulse of one CK cycle duration. On
the falling edge of this pulse, the delay timer starts counting the Time-out period t
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Figure 11-6. Watchdog Reset During Operation
ATmega325/3250/645/6450 features an internal bandgap reference. This reference is used for
Brown-out Detection, and it can be used as an input to the Analog Comparator or the ADC.
The voltage reference has a start-up time that may influence the way it should be used. The
start-up time is given in
reference is not always turned on. The reference is on during the following situations:
1. When the BOD is enabled (by programming the BODLEVEL [1..0] Fuse).
2. When the bandgap reference is connected to the Analog Comparator (by setting the
3. When the ADC is enabled.
ACBG bit in ACSR).
for details on operation of the Watchdog Timer.
CC
INTERNAL
TIME-OUT
RESET
RESET
V
CC
“System and Reset Characteristics” on page
V
CK
BOT-
ATmega325/3250/645/6450
V
t
TOUT
BOT+
300. To save power, the
TOUT
. Refer to
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