LM3710 Datasheet, PDF (1/16 Pages) National Semiconductor (TI) – Microprocessor Supervisory Circuits with Power Fail Input, Low Line Output, Manual Reset and Watchdog Timer

June 2002
LM3710/LM3711
Microprocessor Supervisory Circuits with Power Fail
Input, Low Line Output, Manual Reset and Watchdog
Timer
General Description
The LM3710/LM3711 series of microprocessor supervisory
circuits provide the maximum flexibility for monitoring power
supplies and battery controlled functions in systems without
backup batteries. The LM3710/LM3711 series are available
in MSOP-10 and 9-bump micro SMD packages.
Built-in features include the following:
Reset: Reset is asserted during power-up, power-down, and
brownout conditions. RESET is guaranteed down to V_CC of
1.0V.
Manual Reset Input: An input that asserts reset when pulled
low.
Power-Fail Input: A 1.225V threshold detector for power fail
warning, or to monitor a power supply other than V_CC.
Low Line Output: This early power failure warning indicator
goes low when the supply voltage drops to a value which is
2% higher than the reset threshold voltage.
Watchdog Timer: The WDI (Watchdog Input) monitors one of
the µP’s output lines for activity. If no output transition occurs
during the watchdog timeout period, reset is activated.
Features
n Standard Reset Threshold voltage: 3.08V
n Custom Reset Threshold voltages: For other voltages
between 2.2V and 5.0V in 10mV increments, contact
National Semiconductor Corp.
n No external components required
n Manual-Reset input
n RESET (LM3710) or RESET (LM3711) outputs
n Precision supply voltage monitor
n Factory programmable Reset and Watchdog Timeout
Delays
n Separate Power Fail comparator
n Available in micro SMD package for minimum footprint
n ±0.5% Reset threshold accuracy at room temperature
n ±2% Reset threshold accuracy over temperature
extremes
n Reset assertion down to 1V V_CC (RESET option only)
n 28 µA V_CC supply current
Applications
n Embedded Controllers and Processors
n Intelligent Instruments
n Automotive Systems
n Critical µP Power Monitoring
Typical Application
© 2002 National Semiconductor Corporation DS200118
20011803
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