RE46C803 Carbon Monoxide Detector Companion IC Features Low Quiescent Current Operation from 3V 1.8V Regulated Voltage for CO Detection 3.3V Regulated Voltage for Microcontroller Operation in Boost Mode 9V Boost Converter Horn Driver LED Driver Internal Operational Amplifier Rail-to-Rail Input and Output 10 KHz Gain Bandwidth Product Unity Gain Stable Description The RE46C803 is a low-voltage, low-power CMOS carbon monoxide detector companion IC. The RE46C803 provides all of the analog, interface, and power regulation functions for a microcontroller- based CO or toxic gas detector. It is intended for use in 3V battery applications. It features a boost converter and horn driver circuit suitable for driving a piezoelectric horn, a 3.3V regulator for microcontroller voltage regulation, an LED driver and an operational amplifier. Datasheet DS20005837A-page 1 2017 Microchip Technology Inc. Package Type Functional Block Diagram LEVEL LX SHIFTER EN HRNEN BOOST CEN GATE EN CONTROL REFERENCE VOLTAGE HB GENERATOR 2 I LIMIT HS FEED VDD BOOST VO ERROR REFERENCE AMPLIFIER VOLTAGE GENERATOR 1 1.8V EN 3.3V VREG1 VSS 0.3V INP OPOUT INN VREG2 0.3V VREF LED LEDEN DS20005837A-page 2 Datasheet 2017 Microchip Technology Inc.