Datasheet

332
7674F–AVR–09/09
ATmega164P/324P/644P
26.4 System and Reset Characteristics
Notes: 1. Values indicated represent typical data from design simulation.
2. The Power-on Reset will not work unless the supply voltage has been below V
POT
(falling)
3. This is the limit to which VDD can be lowered without losing RAM data.
Note: 1. V
BOT
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
= V
BOT
during the production test. This guarantees that a Brown-Out Reset will occur before V
CC
drops to
a voltage where correct operation of the microcontroller is no longer guaranteed.
Table 26-4. Reset, Brown-out and Internal Voltage Reference Characteristics
Symbol Parameter Condition Min Typ Max Units
t
RST
(1)
Minimum pulse width on RESET Pin 2.5 ns
V
HYST
Brown-out Detector Hysteresis 50 mV
V
RAM
(3)
RAM Retention Voltage
(1)
50 mV
t
BOD
(1)
Min Pulse Width on Brown-out Reset 2 ns
V
BG
Bandgap reference voltage V
C C
= 2.7V, T
A
= 25°C1.0 1.1 1.2 V
t
BG
(1)
Bandgap reference start-up time V
C C
= 2.7V, T
A
= 25°C4070µs
I
BG
(1)
Bandgap reference current consumption V
C C
= 2.7V, T
A
= 25°C10 µA
Table 26-5. BODLEVEL Fuse Coding
(1)
BODLEVEL 2:0 Fuses Min V
BOT
Typ V
BOT
Max V
BOT
Units
111 BOD Disabled
110 Reserved
V
101 2.5 2.7 2.9
100 4.1 4.3 4.5
011
Reserved
010
001
000