RE46C195S16 [Microchip]

The RE46C195 is a low power, low voltage photoelectric type smoke detector ASIC.  It is pin for pin compatible with the RE46C191 and offers a Chamber Monitor function in lieu of Long-Term Drift compensation.  With minimal external components, this circuit will provide all the required functions and features for a photoelectric smoke detector.  Programmable setup, calibration and feature selection are the key to reduced component count and reduced manufacturing costs.  The low average operating current of the RE46C195 allows smoke detectors to achieve 10-year operation with lithium-ion batteries.  The boost regulator insures proper operation of the infrared diode and the piezoelectric horn under low battery conditions.  The design incorporates a programmable gain integrating photo amplifier for use with an infrared emitter diode.  The infrared emitter drive current is programmable along with smoke alarm limits which provides the designer with exceptional flexibility when designing a smoke detector.

• Two AA Battery Operation
• Low Quiescent Current Operation
• IRED Driver with Programmable IRED Current
• Programmable Integrating Photo Amplifier
• ProgrammableSmoke Alarm Sensitivity Levels
• 6-bit ADC
• 9-Minute Hush Timer for Reduced Sensitivity Level
• Programmable Chamber Test Sensitivity Level
• Programmable Chamber Monitor Level
• Programmable Low Battery Test Time
• Programmable Low Battery Set Point
• Local Alarm Memory
• Interconnect up to 40 Detctors