RE46C180S16F

Sensor And Detector Interfaces Overview

The RE46C180 is a CMOS ionization smoke detector ASIC designed for standalone or interconnected fire alarm systems. It operates on a 6V to 12V supply with standby current as low as 3.8 µA. The device features an internal oscillator, programmable sensitivity thresholds, and alarm memory. Key electrical parameters include a typical supply voltage of 9V, operating temperature range from -10°C to +60°C, and ±5% internal oscillator tolerance. It supports interconnection of up to 40 detectors via the IO pin.

Sensor And Detector Interfaces Feature Summary

• Integrated ionization chamber monitoring with programmable standby, hysteresis, and HUSH sensitivity levels.
• Supports multi-unit interconnect systems with horn synchronization and Auto Alarm Locate capabilities.
• Includes supervisory tests for low battery detection and ionization chamber functionality verification.
• Features alarm memory indication and end-of-life tracking for maintenance scheduling.

Sensor And Detector Interfaces Applications

• Standalone ionization smoke alarms compliant with UL217 standards.
• Interconnected smoke detector networks requiring synchronized horn patterns.
• Fire alarm systems utilizing temporal or continuous horn signaling per NFPA 72.

Sensor And Detector Interfaces Procurement Notes

Verify the specific package variant (PDIP or SOIC) required for your design. Confirm that the ordering suffix matches the desired thermal and mechanical specifications. Ensure compatibility with existing PCB footprints before finalizing orders. Check for any recent datasheet revisions that might affect programming parameters or electrical characteristics.

Sensor And Detector Interfaces Selection Notes

Select this component for applications requiring low quiescent current in battery-powered smoke detectors. Consider the programmable features if custom sensitivity or timer modes are needed. Evaluate the interconnect requirements; this IC supports up to 40 units. Ensure the external components match the typical application circuit values for optimal performance.

Sensor And Detector Interfaces Part Context

The RE46C180 belongs to Microchip's family of specialized analog front-end ICs for safety sensors. It complements other detector ICs by offering robust ionization-specific features like guard amplifiers and chamber voltage control. It is distinct from digital microcontrollers, focusing purely on analog signal processing and timing for smoke detection.

Sensor And Detector Interfaces Replacement Considerations

No direct public substitute part numbers are listed in the official documentation. Designers should evaluate legacy Microchip ionization detector ICs for potential pin-compatible alternatives, though feature sets may vary. Verify all electrical characteristics and programming options when considering cross-references.

Sensor And Detector Interfaces FAQ

How does the RE46C180 handle low battery conditions?

The device performs a low battery check every 80 seconds. If a low battery is detected, it triggers a horn chirp every 40 seconds. A loaded test using the RLED pin ensures accuracy.

What is the purpose of the IO pin?

The IO pin allows interconnection of multiple detectors. It drives high during a local alarm to trigger remote units and includes a charge dump feature to quickly discharge the line after an alarm.

Can the horn pattern be customized?

Yes, the user can program the horn pattern to be either temporal (compliant with NFPA 72) or continuous. Additionally, CO alarm patterns are supported if enabled via the IO input.