RE46C190S16TF

The RE46C190S16TF from Microchip Technology is a versatile integrated circuit designed for photoelectric smoke detection applications. This low-power, low-voltage CMOS device integrates essential features for a smoke detector, requiring minimal external components. It operates with a low quiescent current of 1µA and is suitable for two AA battery operation.

The design incorporates a gain-selectable photo amplifier for use with an infrared emitter/detector pair. An internal oscillator strobes power to the detection circuitry every 10 seconds to minimize standby current, increasing the detection rate if smoke is sensed. The IC includes features like local alarm memory, an internal low battery check every 86 seconds, and chamber integrity testing every 43 seconds.

Key functionalities include an adjustable hush sensitivity, adjustable IRED drive current, and a 9-minute timer for reduced sensitivity mode. The temporal horn pattern supports NFPA 72 emergency evacuation signals. An interconnect pin allows multiple detectors to be linked, so when one unit alarms, all units sound. The device is available in a 16-SOIC package and is designed for surface mounting.

This smoke detector IC is intended for applications that comply with Underwriters Laboratory specifications UL217 and UL268. It is noted that the RE46C191 is an improved version recommended for new designs.