MAX793 Maxim, MAX793 Datasheet - Page 9

• Manufacturer Part Number: MAX793
• Description: 3.0V/3.3V Adjustable Microprocessor Supervisory Circuits
• Manufacturer: Maxim

brownout conditions. RESET is guaranteed to be a
logic low for 0V < V
greater than 1V. Without a backup battery (V
V
Once V
timer keeps RESET low for the reset timeout period
(t
ance (Figure 2). RESET is an open-drain output, and
requires a pull-up resistor to V
4.7kΩ to 1MΩ pull-up resistor that will provide sufficient
current to assure the proper logic levels to the µP.
Figure 2. Timing Diagram, V
CC
RP
); after this interval, RESET becomes high imped-
= V
V
(MAX793/MAX794)
V
V
(MAX793)
V
(MAX793/MAX794)
V
MAX794: V
V
V
(MAX793/MAX794)
V
(RESET PULLED UP TO V
V
(MAX793/MAX794)
SHOWN FOR V
TYPICAL DELAY TIMES REFLECT A 40mV OVERDRIVE
LOWLINE
CC
RESET
CE OUT
BOK
PFO
BATT ON
RESET
WDO
CC
OUT
exceeds the reset threshold, an internal
), RESET is guaranteed valid for V
RESET IN
CC
= 3.3V to 0V, V
= V
_______________________________________________________________________________________
CC
CC
(V
CC
)
RST IN
CC
BATT
< V
3.0V/3.3V Adjustable Microprocessor
/ V
Falling
RST
= 3.6V, CE IN = GND, PFI = V
V
RST
)
LL
CC
V
, provided V
RST
(Figure 3). Use a
4 s
20 s
20 s
10 s
CC
CC
.
BATT
BATT
V
SW
≥ 1V.
is
=
25 s
25 s
25 s
25 s
25 s
If a brownout condition occurs (V
reset threshold), RESET goes low. Each time RESET is
asserted, it stays low for the reset timeout period. Any
time V
timer restarts.
The watchdog output (WDO) can also be used to initi-
ate a reset. See the Watchdog Output section.
The RESET output is the inverse of the RESET output,
and it can both source and sink current.
V
BATT
Supervisory Circuits
CC
V
BATT
goes below the reset threshold, the internal
CC
dips below the
9