General Description
The RE46C143 is low power CMOS photoelectric type smoke detector IC. With minimal external components this circuit will provide 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. An internal oscillator strobes power to the smoke detection circuitry for 100us every 8.1 seconds to keep standby current to a minimum. 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 and chamber integrity is performed every 40 seconds when in standby. The alarm horn pattern utilizes a 75% duty cycle.

FEATUREs
• Internal Power On Reset
• Low Quiescent Current Consumption
• Available in 16L PDIP or 16L N SOIC
• ESD Protection on all Pins
• Interconnect up to 40 Detectors
• 75% Duty Cycle Horn Pattern
• Low Battery and Chamber Test
• Compatible with Motorola MC145010
• Available in Standard Packaging or RoHS Compliant Pb Free Packaging.