RE46C421

The Microchip RE46C421 is a low-power smoke detector Analog Front End (AFE) intended for battery-powered applications. The AFE provides all the needed analog, interface and power regulation functions for a microcontroller-(MCU) based multicriteria smoke detector. It can be powered by two AA batteries or a single lithium battery. The RE46C421 features a dual-input integrating photo amplifier to interface with a photoelectric smoke chamber, two independently controlled programmable LED drivers, an analog buffer circuit (ABUF) for monitoring system voltages and a 3.3V regulator. The RE46C421 is capable of meeting UL 217 9th Ed and UL 268 7th Ed specifications and can be easily adapted to new editions with its programmable design and rich feature set. For designs that do not require two integrating photo amplifiers, see the RE46C420, which instead features a four terminal CO monitor. For designs that require both CO monitoring and dual photo input, see the RE46C422.