Features
• Two AA Battery Operation
• Low Quiescent Current Consumption
• Local Alarm Memory
• Interconnect Up to 40 Detectors
• Nine-Minute Timer for Sensitivity Control
• Temporal or Continuous Horn Pattern
• Internal Low Battery and Chamber Test
• All Internal Oscillator
• Internal Infrared Emitter Diode (IRED) Driver
• Adjustable IRED Drive Current
• Adjustable Hush Sensitivity
• Two Percent Low Battery Set Point
• Pin-for-Pin Compatible with RE46C190
General Description
The RE46C191 is a low-power, low-voltage CMOS
photoelectric-type smoke detector IC. With minimal
external components, this circuit provides all the
required features for a photoelectric-type smoke
detector.
The design incorporates a gain-selectable photo
amplifier for use with an infrared emitter/detector pair.
To keep the standby current to a minimum, an internal
oscillator strobes power to the smoke detection
circuitry every 10 seconds. If smoke is sensed, the
detection rate is increased to verify an Alarm condition.
A High-Gain mode is available for push button chamber
testing.
A check for a Low Battery condition is performed every
86 seconds and the chamber integrity is tested once
every 43 seconds when in Standby mode. The temporal
horn pattern supports the NFPA 72 emergency
evacuation signal.
An interconnect pin allows multiple detectors to be
connected, such that when one unit alarms, all units
sound.
An internal nine-minute timer can be used for a
Reduced Sensitivity mode.
Package