Features
• 6-12V Operation
• Low Quiescent Current Consumption
• Programmable Standby Sensitivity
• Programmable HUSH Sensitivity
• Programmable Hysteresis
• Programmable Chamber Voltage for Push-to-Test
(PTT) and Chamber Test
• Programmable ±150 mV Low-Battery Set Point
• Internal Ionization Chamber Test
• Programmable Low Battery Test Duration
• Internal Power-on Reset (POR) and Power-Up
Low Battery Test
• Alarm Memory
• IO Filter and Charge Dump
• Interconnect Up to 40 Detectors
• ±5% All Internal Oscillator
• 9-Minute Timer for Sensitivity Control
• Temporal Horn Pattern
• Guard Outputs for Ion Detector Input
• ±0.75 pA Detect Input Current
• 10-year End of Life Indication
• Chamber Monitor Warning
Description
The RE46C181 is a next generation low-power, CMOS
ionization-type, smoke detector IC. With minimal
external components, this circuit will provide all the
required features for an ionization-type smoke
detector.
An on-chip oscillator strobes power to the smoke
detection circuitry for 5 ms every 10s to keep the
standby current to a minimum.
A check for a low battery condition is performed every
80s and an ionization chamber test is performed once
every 320s when in Standby mode. The temporal horn
pattern complies with the National Fire Protection
Association NFPA 72® National Fire Alarm and
Signaling Code® for emergency evacuation signals.
An interconnect pin allows multiple detectors to be
connected, such that when one unit alarms, all units will
sound. A charge dump feature quickly discharges the
interconnect line when exiting a Local Alarm condition.
The interconnect input is also digitally filtered.
An internal 9-minute timer can be used for a Reduced
Sensitivity mode.
An alarm memory feature allows the user to determine
whether the unit has previously entered a Local Alarm
condition.