Datasheet

1 of 9 121906
FEATURES
 5V or 3.3V power-on reset
 True 3V operation power switch
 Switches to battery at 3.8V (2.6V for 3.3V
versions)
 Excellent for systems designed to operate
with dual power supplies
 Asserts resets during power transients
 Maintains reset for 350ms after V
CC
returns to
an in-tolerance condition
 Reduces need for discrete components
 Precision temperature-compensated voltage
reference and voltage sensor
 8-pin DIP or space saving 8-pin SO surface
mount available
 CMOS reset output for low current operation
 Operating temperature of -40°C to +85°C
 Perfect for PIC microprocessor applications
PIN ASSIGNMENT
DS1836A/C (*DS1836B/D)
PIN DESCRIPTION
V
CC
- Power Supply Input
V
BAT
- Battery Supply Input
NC - No Connect
V
OUT
- Power Supply Output
GND - Ground
IN - Sense Input
NMI - Non-maskable Interrupt
RST (*RST) - Reset Output
DESCRIPTION
The DS1836 MicroManager performs three vital system functions. First, a precision temperature-
compensated reference and comparator circuit monitor the status of the voltage on V
CC
and when an out-
of-tolerance condition is detected, an internal power-fail signal is generated that forces the reset active. If
V
CC
continues to degrade, it switches to the battery supply when V
CC
drops below 3.8V (2.6V for 3.3V
versions). When V
CC
exceeds 3.9V (2.8V for 3.3V versions); V
OUT
will again be supplied from V
CC
.
Reset will remain active for 350 ms after V
CC
returns to an in-tolerance condition.
Lastly, the DS1836 supports a sense input that sends a non-maskable interrupt whenever the sense input
drops below 1.25V.
DS1836/A/B/C/D
3.3V/5V MicroManage
r
www.maxim-ic.com
8-Pin SO (150mil)
1
2
3
4
8
7
6
5
V
CC
V
BAT
NC
V
OUT
RST(*RST)
NMI
IN
GND
8-Pin DIP (300mil)
V
CC
V
BAT
NC
V
OUT
RST(*RST)
NMI
IN
GND
1
2
3
4
8
7
6
5