DS1834/A/D
Dual EconoReset with Pushbutton
www.dalsemi.com
FEATURES
5V power-on reset
3.3V power-on reset
Internal power is drawn from higher of either
the 5V
IN
input or the 3.3V
IN
input
Excellent for systems designed to operate
with dual power supplies
Asserts resets during power transients
Pushbutton reset input for system override
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, 8-pin SOIC, and 8-pin
µ-SOP
available
CMOS output for low current operation on
the DS1834 and DS1834D
Operating temperature of -40°C to +85°C
PIN ASSIGNMENT
5V
IN
5V RST
5V TOL
GND
1
2
3
4
8
7
6
5
3.3V
IN
3.3V RST
3.3V TOL
PBRST
DS1834 8-Pin DIP (300-mil)
5V
IN
5V RST
5V TOL
GND
1
2
3
4
8
7
6
5
3.3V
IN
3.3V RST
3.3V TOL
PBRST
DS1834 8-Pin SOIC (150-mil)
5V
IN
5V RST (*RST)
5V TOL
GND
1
2
3
4
8
7
6
5
3.3V
IN
3.3V RST (*RST)
3.3V TOL
PBRST
DS1834 8-Pin
µ-SOP
(118-mil)
PIN DESCRIPTION
5V
IN
5V
RST
(*RST)
5V TOL
GND
- 5V Power Supply Input
- 5V Reset Output
- Selects 5V Input Tolerance
- Ground
PBRST
- Pushbutton Reset
3.3V TOL
- Selects 3.3V Input Tolerance
3.3V
RST
(*RST) - 3.3V Reset Output
3.3V
IN
- 3.3V Power Supply Input
*DS1834D Active High Reset
DESCRIPTION
The DS1834 Dual EconoResets monitors three vital system conditions: 5-volt supply, 3.3-volt supply,
and an external override. First a precision temperature reference and comparator circuit monitor the status
of the 5-volt supply and the 3.3-volt supply. When an out-of-tolerance condition is detected, an internal
power-fail signal is generated which forces the reset of the affected supply to an active state.
Lastly, the DS1834 supports an external reset via an internally debounced pushbutton input. When the
pushbutton is pulled low both resets will be asserted for approximately 350 ms after the pushbutton is
released.
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071700
DALLAS [ DALLAS SEMICONDUCTOR ]
