ATMEGA48V_11 ATMEL [ATMEL Corporation], ATMEGA48V_11 Datasheet - Page 46

• Manufacturer Part Number: ATMEGA48V_11
• Description: 8-bit Atmel Microcontroller with 4/8/16K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

11.3
2545T–AVR–05/11
Power-on reset
Figure 11-1. Reset logic.
A power-on reset (POR) pulse is generated by an On-chip detection circuit. The detection level
is defined in
V
well as to detect a failure in supply voltage.
A power-on reset (POR) circuit ensures that the device is reset from power-on. Reaching the
power-on reset threshold voltage invokes the delay counter, which determines how long the
device is kept in RESET after V
when V
Figure 11-2. MCU start-up, RESET tied to V
CC
is below the detection level. The POR circuit can be used to trigger the start-up Reset, as
INTERNAL
TIME-OUT
BODLEVEL [2..0]
RSTDISBL
CC
RESET
RESET
V
decreases below the detection level.
CC
“System and reset characteristics” on page
Pull-up resistor
FILTER
SPIKE
V
V
POT
RST
CC
t
TOUT
CKSEL[3:0]
rise. The RESET signal is activated again, without any delay,
Power-on reset
Reset circuit
SUT[1:0]
reset circuit
Brown-out
Watchdog
Watchdog
oscillator
generator
circuit
timer
Clock
CC.
CK
register (MCUSR)
MCU status
DATA BUS
Delay counters
307. The POR is activated whenever
ATmega48/88/168
TIMEOUT
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