AT90CAN128-16AE ATMEL Corporation, AT90CAN128-16AE Datasheet - Page 50

• Manufacturer Part Number: AT90CAN128-16AE
• Description: 8-bit Avr Microcontroller With 128K Bytes of Isp Flash And CAN Controller.flash (Kbytes) 128 Vcc (V) 2.7-5.5 EEPROM (Kbytes) 4 SRAM (bytes) 4K CAN (mess. Obj.) 15
• Manufacturer: ATMEL Corporation

Power-on Reset
External Reset
50
AT90CAN128
A Power-on Reset (POR) pulse is generated by an On-chip detection circuit. The detec-
tion level is defined in Table 19. 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 23. MCU Start-up, RESET Tied to V
Figure 24. MCU Start-up, RESET Extended Externally
An External Reset is generated by a low level on the RESET pin. Reset pulses longer
than the minimum pulse width (see Table 19) will generate a reset, even if the clock is
not running. Shorter pulses are not guaranteed to generate a reset. When the applied
signal reaches the Reset Threshold Voltage – V
counter starts the MCU after the Time-out period – t
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
CC
RST
t
TOUT
CC
RST
rise. The RESET signal is activated
TOUT
– on its positive edge, the delay
– has expired.
CC
4250C–CAN–03/04
is below the