ATMEGA2561V ATMEL [ATMEL Corporation], ATMEGA2561V Datasheet - Page 58

• Manufacturer Part Number: ATMEGA2561V
• Description: 8-bit Microcontroller with 64K/128K/256K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

Power-on Reset
58
ATmega640/1280/1281/2560/2561
Figure 24. Reset Logic
Table 26. Reset Characteristics
Notes:
A Power-on Reset (POR) pulse is generated by an On-chip detection circuit. The detec-
tion level is defined in Table 26. The POR is activated whenever V
detection level. The POR circuit can be used to trigger the start-up Reset, as well as to
detect a failure in supply voltage.
A Power-on Reset (POR) circuit ensures that the device is reset from Power-on. Reach-
ing the Power-on Reset threshold voltage invokes the delay counter, which determines
how long the device is kept in RESET after V
again, without any delay, when V
Symbol
BODLEVEL [2..0]
V
V
t
RST
POT
RST
1. Values are guidelines only. Actual values are TBD.
2. The Power-on Reset will not work unless the supply voltage has been below V
(falling)
Parameter
Power-on Reset Threshold
Voltage (rising)
Power-on Reset Threshold
Voltage (falling)
Minimum pulse width on RESET
Pin
RESET Pin Threshold Voltage
Pull-up Resistor
JTAG Reset
Register
FILTER
SPIKE
(2)
CKSEL[3:0]
Power-on Reset
Reset Circuit
SUT[1:0]
(1)
Brown-out
Watchdog
Oscillator
Generator
CC
Circuit
Clock
decreases below the detection level.
CK
Register (MCUSR)
Condition
MCU Status
CC
DATA BUS
rise. The RESET signal is activated
Delay Counters
TBD
TBD
TBD
TBD
Min
TBD
TBD
TBD
TBD
Typ
TIMEOUT
CC
2549K–AVR–01/07
is below the
Max
TBD
TBD
TBD
TBD
Units
ns
V
V
V
POT