ISL88011IH523Z INTERSIL [Intersil Corporation], ISL88011IH523Z Datasheet - Page 6

• Manufacturer Part Number: ISL88011IH523Z
• Description: 5-Pin Voltage Supervisors with Adjustable Power-On Reset, Dual Voltage Monitoring or Watchdog Timer Capability
• Manufacturer: INTERSIL [Intersil Corporation]

Principles of Operation
The ISL88011 - ISL88015 devices provide those functions
needed for critical voltage monitoring. These features
include Power On Reset control, customizable supply
voltage supervision, Watchdog Timer capability, and manual
reset assertion. By integrating all of these features into a
small 5-pin SOT23 package and using only 5.5µA of supply
current, the ISL88011 - ISL88015 devices can assist in
lowering system cost, reducing board space requirements,
and increasing the reliability of a system.
Low Voltage Monitoring
During normal operation, these supervisors monitor both the
voltage level of V
(ISL88012,14,15). The device asserts a reset if any of these
voltages falls below their respective trip points. The reset
signal effectively prevents the system from operating during
a power failure or brownout condition. This reset signal
remains asserted until V
exceed their voltage threshold setting for the reset time
delay period t
RST
V
VMON
MR
RST
DD
POR
DD
V
1V
of 200ms (See Figure 1).
THVDD
(ISL88011,12,13) and/or VMON
DD
and the voltage on VMON
ISL88011, ISL88012, ISL88013, ISL88014, ISL88015
6
t
POR
FIGURE 1. VOLTAGE MONITORING TIMING DIAGRAM
t
RPD
t
POR
The ISL88012, ISL88014 and ISL88015 allow users to
customize the minimum voltage sense level on the VMON
input pin. To do this, connect an external resistor divider
network to the VMON pin in order to set the trip point to
some voltage above 600mV according to the following
equation (See Figure 2):
V
FIGURE 2. USING VMON TO MONITOR V
INTRIP
t
RPD
V
=
V
IN
THVMON
0.6
×
R
(
-------------------------- -
R 1
1
R 2
t
R
POR
+
VMON
2
R 2
)
>t
MR
ISL88012
ISL88014
ISL88015
t
POR
IN
VIA RESISTORS
February 13, 2006
(EQ. 1)
FN8093.0