ATMEGA169 ATMEL [ATMEL Corporation], ATMEGA169 Datasheet - Page 39

• Manufacturer Part Number: ATMEGA169
• Description: 8-bit Microcontroller with 16K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

Power-on Reset
2514P–AVR–07/06
A Power-on Reset (POR) pulse is generated by an On-chip detection circuit. The detec-
tion level is defined in Table 16. 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
Figure 15. MCU Start-up, RESET Tied to V
Figure 16. MCU Start-up, RESET Extended Externally
INTERNAL
INTERNAL
TIME-OUT
TIME-OUT
RESET
RESET
RESET
RESET
V
V
CC
CC
V
V
V
POT
POT
RST
t
TOUT
CC
decreases below the detection level.
V
RST
CC
t
TOUT
CC
rise. The RESET signal is activated
ATmega169/V
CC
is below the
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