338
8272E–AVR–04/2013
ATmega164A/PA/324A/PA/644A/PA/1284/P
28.4
System and reset characteristics
Notes:
1. The Power-on Reset will not work unless the supply voltage has been below VPOT (falling).
Note:
1. VBOT may be below nominal minimum operating voltage for some devices. For devices where this is the case, the device is
tested down to V
CC = VBOT during the production test. This guarantees that a Brown-Out Reset will occur before VCC drops to
a voltage where correct operation of the microcontroller is no longer guaranteed. The test is performed using
BODLEVEL = 101 and BODLEVEL = 110.
28.5
External interrupts characteristics
Table 28-12. Reset, Brown-out and Internal Voltage Reference characteristics.
Symbol
Parameter
Condition
Min.
Typ.
Max.
Units
VPOT
Power-on Reset Threshold Voltage (rising)
1.1
1.4
1.6
V
Power-on Reset Threshold Voltage (falling)
0.6
1.3
1.6
VRST
RESET Pin Threshold Voltage
0.2VCC
0.9VCC
tRST
Minimum pulse width on RESET Pin
2.5
s
VHYST
Brown-out Detector Hysteresis
50
mV
tBOD
Min Pulse Width on Brown-out Reset
2
s
VBG
Bandgap reference voltage
V
CC= 2.7V, TA = 25C1.0
1.1
1.2
V
tBG
Bandgap reference start-up time
VCC= 2.7V, TA = 25C40
70
s
IBG
Bandgap reference current consumption
VCC= 2.7V, TA = 25C10
A
Table 28-13. BODLEVEL fuse coding
(1).
BODLEVEL 2:0 Fuses
Min. V
BOT
Typ. V
BOT
Max. V
BOT
Units
111
BOD disabled
110
1.7
1.8
2.0
V
101
2.5
2.7
2.9
100
4.1
4.3
4.5
011
Reserved
010
001
000
Table 28-14. Asynchronous external interrupt characteristics.
Symbol
Parameter
Condition
Min.
Typ.
Max.
Units
tINT
Minimum pulse width for asynchronous external interrupt
50
ns