Datasheet

ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +4.75V to +5.5V for MAX81_L, V
CC
= +4.5V to +5.5V for MAX81_M, V
BATT
= 2.8V, T
A
= T
MIN
to T
MAX
, unless otherwise
noted. Typical values are at T
A
= +25°C.)
MAX817L/M, MAX818L/M, MAX819L/M*
+5V Microprocessor Supervisory Circuits
_______________________________________________________________________________________ 3
V
PFO
= 0V
V
PFI
> 1.30V, I
SOURCE
= 40µA, V
CC
> 4.5V
MAX81_M
V
PFI
< 1.20V, I
SINK
= 3.2mA, V
CC
> 4.50V
MAX81_L
WDI = GND, time average
From V
RST
, V
CC
falling at 10V/ms
WDI = V
CC
, time average
V
CC
= 5V
MAX81_ _C, V
CC
= 1V, V
CC
falling,
V
BATT
= 0V, I
SINK
= 50µA
V
CC
> V
RST(MAX),
I
SOURCE
= 800µA
V
CC
< V
RST(MIN),
I
SINK
= 3.2mA
V
IL
= 0.4V, V
IH
= 0.8V
CC
CONDITIONS
µA250 500
PFO Short-Circuit Current
V
CC
- 1.5V
OH
PFO Output Voltage
V
0.4V
OL
nA-25 0.01 25I
PFI
PFI Input Current
mV4PFI Input Hysteresis
V1.20 1.25 1.30V
PFT
PFI Input Threshold
µA
-20 -15
WDI Input Current (Note 5)
120 160
V
3.5V
IH
WDI Input Threshold (Note 4)
0.8V
IL
ns50t
WDI
WDI Pulse Width
V
4.25 4.40 4.50
V
RST
Reset Threshold
4.50 4.65 4.75
sec1.00 1.60 2.25t
WD
Watchdog Timeout Period
µs100
V
CC
to RESET Delay
0.3
mV25Reset Threshold Hysteresis
ms140 200 280t
RP
Reset Timeout Period
V
CC
- 1.5V
OH
0.4
V
OL
UNITSMIN TYP MAXSYMBOLPARAMETER
MAX81_ _E, V
CC
= 1.2V, V
CC
falling,
V
BATT
= 0V, I
SINK
= 100µA
V
0.3
RESET Output Voltage
0.8
V
2.0
V
IL
MR Input Threshold
µs1
MR Pulse Width
V
IH
ns100
MR Pulse that Would Not Cause
a Reset
ns120
MR to Reset Delay
kΩ45 63 85
MR Pull-Up Resistance
RESET AND WATCHDOG TIMER
POWER-FAIL COMPARATOR (MAX817/MAX819 only)
MANUAL RESET INPUT (MAX819 only)