Rainbow Electronics AT90LS4433 - Manual (Page 22)

22
AT90S/LS4433
1042G–AVR–09/02
Figure 24. Reset Logic
Note: 1. The Power-on Reset will not work unless the supply voltage has been below V
POT
(falling).
Table 4. Reset Characteristics (V
CC
= 5.0V)
Symbol Parameter Min Typ Max Units
V
POT
(1)
Power-on Reset
Threshold
Voltage, rising
1.0 1.4 1.8 V
Power-on Reset
Threshold
Voltage, falling
0.4 0.6 0.8 V
V
RST
RESET Pin
Threshold
Voltage
0.6 V
CC
V
V
BOT
Brown-out Reset
Threshold
Voltage
2.2
(BODLEVEL=1)
2.7
(BODLEVEL=1)
3.0
(BODLEVEL=1)
V
3.5
(BODLEVEL=0)
4.0
(BODLEVEL=0)
4.5
(BODLEVEL=0)
MCU Status
Register (MCUSR)
Brown-out
Reset Circuit
Power-on Reset
Circuit
BODEN
BODLEVEL
Delay Counters
CKSEL[2:0]
CK
Full
WDRF BORF
EXTRF
PORF
DATA BUS
Reset Circuit
Watchdog
Timer
On-chip
RC Oscillator
Counter Reset
Inter
nal Reset
RESET
V
CC