LM3710/LM3711 Microprocessor Supervisory Circuits with Power Fail Input, Low Line Output, Manual Reset and Watchdog Time...
LM3710/LM3711 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 VCC 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 VCC. 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 RES...