DS1836/A/B/C/D
3.3V/5V MicroManager
www.dalsemi.com
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 350 ms 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 SOIC surface
mount available
CMOS reset output for low current operation
Operating temperature of -40擄C to +85擄C
Perfect for PIC microprocessor applications
PIN ASSIGNMENT
V
CC
V
BAT
NC
V
OUT
1
2
3
4
8
7
6
5
RST(*RST)
NMI
IN
GND
8-Pin DIP (300-mil)
V
CC
V
BAT
NC
V
OUT
1
2
3
4
8
7
6
5
RST(*RST)
NMI
IN
GND
8-Pin SOIC (150-mil)
DS1836A/C (*DS1836B/D)
PIN DESCRIPTION
V
CC
V
BAT
NC
V
OUT
GND
IN
NMI
RST
(*RST)
- Power Supply Input
- Battery Supply Input
- No Connect
- Power Supply Output
- Ground
- Sense Input
- Non-maskable Interrupt
- 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 which forces the reset active.
If V
CC
continues to degrade it switches to the battery supply when V
CC
drops below 3.8 volts (2.6 volts
for 3.3-volt versions). When V
CC
exceeds 3.9 volts (2.8 volts for 3.3-volt 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 1.25 volts.
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