Datasheet

MAX791
Microprocessor Supervisory Circuit
4 _______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= 4.75V to 5.5V, VBATT = 2.8V, T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
Note 1: Either V
CC
or VBATT can go to 0V, if the other is greater than 2.0V.
Note 2: The supply current drawn by the MAX791 from the battery (excluding I
OUT
) typically goes to 10µA when
(VBATT - 1V) < V
CC
< VBATT. In most applications, this is a brief period as V
CC
falls through this region.
Note 3: "+" = battery-discharging current, "-" = battery-charging current.
Note 4: WDI is internally connected to a voltage-divider between V
OUT
and GND. If unconnected, WDI is driven to 1.6V (typ),
disabling the watchdog function.
Note 5: The chip-enable resistance is tested with V
CC
= 4.75V V
C
E
IN
= V
C
E
OUT
= V
CC
/ 2.
Note 6: The chip-enable propagation delay is measured from the 50% point at
C
E
IN to the 50% point at
C
E
OUT.
ns
61050source impedance driver, C
LOAD
= 50pF
C
E
IN-to-C
E
OUT Propagation
Delay (Note 6)
-50 -10WDI = 0V
µA
20 50WDI = V
OUT
WDI Input Current
0.75 x V
CC
V
IH
µA23 250
M
R
= 0V
M
R
Pull-Up Current
µs7
75 150Enabled mode
M
R
-to -
R
E
S
E
T
Propagation Delay
C
E
IN-to-
C
E
OUT Resistance
(Note 5)
µA±0.005 ±1Disabled mode
C
E
IN Leakage Current
µs15Power down
R
E
S
E
T
-to-
C
E
OUT Delay
nA±0.01 ±25PFI Leakage Current
V1.25V
CC
= 5V
M
R
Threshold
mA0.1 0.75 2.0
µs
Disabled mode,
C
E
OUT = 0V
25 15
C
E
OUT Short-Circuit Current
(Reset Active)
V1.20 1.25 1.30V
CC
= 5VPFI Input Threshold
V
0.8V
IL
WDI Threshold Voltage
(Note 4)
UNITSMIN TYP MAX
M
R
Minimum Pulse Width
CONDITIONSPARAMETER
0.4I
SINK
= 3.2mA
V
3.5I
SOURCE
= 1µA, V
CC
= 5V
P
F
O
Output Voltage
mA60Output sink current
µA115100Output source current
P
F
O
Short-Circuit Current
µs
55V
IN
= 20mV, V
OD
= 15mV
PFI-to-
P
F
O
Delay
15V
IN
= -20mV, V
OD
= 15mV
3.5V
CC
= 5V, I
OUT
= -100µA
V
2.7V
CC
= 0V, VBATT = 2.8V, I
OUT
= 1µA
C
E
OUT Output Voltage High
(Reset Active)
POWER-FAIL COMPARATOR
CHIP-ENABLE GATING
MANUAL RESET INPUT