Datasheet

MAX6301–MAX6304
+5V, Low-Power µP Supervisory Circuits
with Adjustable Reset/Watchdog
_______________________________________________________________________________________
3
10,000
0
0.001 0.01 0.1 1 10 100 1000
RESET TIMEOUT PERIOD
vs. C
SRT
1
MAX6301-4 toc01
C
SRT
(nF)
RESET TIMEOUT PERIOD (ms)
10
100
1000
V
CC
= 5V
10,000
0
0.001 0.01 0.1 1 10 100 1000
EXTENDED-MODE
WATCHDOG TIMEOUT PERIOD vs. C
SWT
(WDS = V
CC
)
1
MAX6301-4 toc02
C
SWT
(nF)
WATCHDOG TIMEOUT PERIOD (s)
10
100
1000
V
CC
= 5V
10,000
0.1
0.001 0.01 0.1 1 10 100 1000
NORMAL-MODE
WATCHDOG TIMEOUT PERIOD vs. C
SWT
(WDS = GND)
1
MAX6301-4 toc03
C
SWT
(nF)
WATCHDOG TIMEOUT PERIOD (ms)
10
100
1000
V
CC
= 5V
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +2V to +5.5V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V
CC
= +5V and T
A
= +25°C.)
Note 1: Reset is guaranteed valid from the selected reset threshold voltage down to the minimum V
CC
.
Note 2: WDS = V
CC
, WDI unconnected.
Note 3: Precision timing currents of 500nA are present at both the SRT and SWT pins. Timing capacitors connected to these nodes
must have low leakage consistent with these currents to prevent timing errors.
Note 4: The sink/source is supplied through a resistor, and is proportional to V
CC
(Figure 8). At V
CC
= 2V, it is typically ±24µA.
__________________________________________Typical Operating Characteristics
(C
SWT
= C
SRT
= 1500pF, T
A
= +25°C, unless otherwise noted.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
WATCHDOG TIMER
V
IH
0.7 x V
CC
WDI, WDS Input Threshold
V
IL
0.3 x V
CC
V
V
CC
= 4.5V to 5.5V 30
WDI Pulse Width t
WP
V
CC
= 2V to 4.5V 60
ns
WDI, WDS Leakage Current Extended mode disabled ±1 µA
WDI Sink/Source Current (Note 4) Extended mode enabled ±70 µA
WDS = GND, C
SWT
= 1500pF 2.8 4.0 5.2 ms
Watchdog Timeout Period
(Note 3)
t
WD
WDS = V
CC
, C
SWT
= 1500pF 1.4 2.0 2.6 s