IMP1811
P
OWER
M
ANAGEMENT
Key Features
Low Power, 5V µP Reset
– Active LOW, Open-Drain Output
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Improved Dallas DS1811 replacement
— 50% lower maximum supply current
The IMP1811 supply voltage monitor is an improved, low-power
replacement for the Dallas Semiconductor DS1811. Maximum supply
current over temperature is a low 20µA, representing 50 percent lower
power as compared to the DS1811.
Low Supply Current
— 20µA maximum (5.5V)
Automatically restarts a microprocessor after
power failure
150ms reset delay after VCC returns to an
in-tolerance condition
Active LOW power-up reset
The IMP1811 issues an active LOW reset signal whenever the monitored
supply is out-of-tolerance. A precision reference and comparator circuit
monitor power supply (VCC) level. Tolerance level options are 5-, 10- and
15-percent. When an out-of-tolerance condition is detected, an internal
power-fail signal is generated which forces an active LOW reset signal.
After VCC returns to an in-tolerance condition, the reset signal remains
active for 150ms to allow the power supply and system microprocessor
to stabilize.
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Precision temperature-compensated voltage
reference and comparator
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Eliminates external components
Low-cost TO-92 package
Compact surface mount SOT-23 package
Operating temperature –40°C to +85°C
The IMP1811 is designed with a open-drain output stage and operates
over the extended industrial temperature range. Devices are available in
compact surface mount SOT-23 packages and 3-lead TO-92 packages.
Other low power products in this family include the IMP1810/12/15/16/17,
IMP1233D and IMP1233M.
Applications
Family Selection Guide
◆ Set-top boxes
◆ Cellular phones
◆ PDAs
◆ Energy management systems
◆ Embedded control systems
◆ Printers
RESET Voltage RESET Time Output RESET
Part
(V)
(ms)
Stage Polarity
IMP1810
IMP1811
IMP1812
IMP1815
IMP1816
IMP1817
4.620, 4.370, 4.120
4.620, 4.350, 4.130
4.620, 4.350, 4.130
3.060, 2.880, 2.550
3.060, 2.880, 2.550
3.060, 2.880, 2.550
150
150
150
150
150
150
350
350
Push-Pull
Open-Drain
Push-Pull
Push-Pull
Open-Drain
Push-Pull
LOW
LOW
HIGH
LOW
LOW
HIGH
LOW
LOW
◆ Single board computers
IMP1233D 4.625, 4.375, 4.125
IMP1233M 4.625, 4.375, 2.720
Open-Drain
Open-Drain
Block Diagram
Typical Application
VCC
1
V
CC
Supply
Tolerance
Bias
5.5kΩ
IMP1811
IMP1811
2
RESET
Microprocessor
RESET
+
Delay
150ms Typical
RESET
–
GND
Reference
3
1811_02.eps
GND
1811_01.eps
©
1999 IMP, Inc.
408-432-9100/www.impweb.com
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