ds1831bst-r Maxim Integrated Products, Inc., ds1831bst-r Datasheet - Page 9

• Manufacturer Part Number: ds1831bst-r
• Description: Ds1831, Ds1831a, Ds1831b Multisupply Micromonitor
• Manufacturer: Maxim Integrated Products, Inc.

NON-MASKABLE INTERRUPT CIRCUIT EXAMPLE Figure 9
Example:
Therefore:
Resulting In: R1 = 820kW
Repeat the same steps to solve for R3 and R4 with V
OPERATION - WATCHDOG TIMER
The watchdog timer function (DS1831A only) forces the
does not have a transition (high-to-low or low-to-high) within the predetermined time period. The time-
out period is determined by the condition of the TD
the minimum watchdog time-out would be 10ms, TD floating would yield a minimum time-out of 100ms,
and TD
starts when at least one of the
pin prior to time-out, the watchdog timer is reset and begins to time-out again. If the watchdog timer is
allowed to time-out, then the
The
output would be connected to one of the Pushbutton inputs and would not require an external pull-up
resistor. The value of the resistors is not critical in most cases but must be set low enough to pull the
output to a high state. A common value used is 10kW. If a
an additional pull-up resistor can be used (to improve speed of transitions) but is not required.
WDS
WD
connected to V
output is an open-drain output and must be pulled up externally. In most applications this
V
11.50V =
SENSE1
V
SENSE2
= 11.50V trip point V
R1 +
R3
R4
CC
100
V
SENSE1
WDS
100
would provide a time-out of 1000ms minimum. Time-out of the watchdog
RST
k
W
k
W
output is pulsed active for a minimum of 100µs.
outputs becomes inactive (high). If a transition occurs on the ST input
R1
R2
X 1.25V
PBRST
GND
IN2
IN1
SENSE1
5V
WD
SENSE2
9 of 14
=
DS1831
pin (see Table 1). If TD
.
WDS
WDS
R1 +
R2
R2
output is connected to a pushbutton input
signal active (low) when the
PBRST
MPBRST
NMI1
NMI2
3.3V
X 1.25V
WD
V
CC
is connected to ground
10 KW
ST
input