RE46C140S16F

Sensor And Detector Interfaces Overview

The RE46C140S16F is a CMOS photoelectric smoke detector ASIC manufactured by Microchip Technology. It operates on a supply voltage of 5V to 12V, with typical standby currents ranging from 4µA to 8µA and active currents up to 3mA. The device features an internal oscillator with a nominal period of 10ms and supports interconnection of up to 40 detectors via the IO pin. It includes a 10-minute timer mode for sensitivity control and generates a temporal horn pattern compliant with NFPA 72 standards. The component is housed in a 16-pin Narrow SOIC package.

Sensor And Detector Interfaces Feature Summary

• Integrated gain-selectable photo amplifier for infrared emitter/detector pairs
• Bidirectional interconnect capability supporting up to 40 linked units
• Internal low battery detection and photo chamber integrity testing
• Programmable 10-minute timer mode for temporary sensitivity reduction

Sensor And Detector Interfaces Applications

• Photoelectric smoke alarm systems requiring UL217 compliance
• Multi-unit interconnected fire detection networks
• Battery-powered residential smoke detectors
• Smoke alarms utilizing push-button chamber testing functions

Sensor And Detector Interfaces Procurement Notes

Verify the specific suffix 'S16F' against the manufacturer's current datasheet revision DS22179B to confirm packaging and material composition details. Ensure that the ordering information matches the exact RoHS compliant lead-free packaging designation provided in the official documentation before finalizing purchase orders.

Sensor And Detector Interfaces Selection Notes

Select this component for applications requiring low quiescent current consumption and integrated horn driving capabilities. Consider the 16-pin Narrow SOIC package constraints during PCB layout. Verify compatibility with external components such as piezoelectric transducers and infrared emitters/detectors based on the typical application circuit requirements.

Sensor And Detector Interfaces Part Context

The RE46C140 belongs to the R&E International family of smoke detector ICs, now under Microchip Technology. This series provides specialized analog front-end processing for photoelectric sensors. The S16F variant specifically denotes the surface-mount narrow SOIC package configuration with standard packaging materials.

Sensor And Detector Interfaces Replacement Considerations

RE46C140SW16TF is listed as a direct substitute.

Sensor And Detector Interfaces FAQ

How does the interconnect feature function?

The bidirectional IO pin allows multiple detectors to be connected so that when one unit alarms, all units sound. It includes protection for signaling units with higher supply voltages.

What is the purpose of the 10-minute timer mode?

The timer mode reduces sensitivity for 10 minutes by switching the smoke comparator reference to an external voltage on the VSEN pin, useful for preventing nuisance alarms during cooking or similar activities.

How is the low battery condition detected?

An internal reference compares the divided VDD supply voltage every 40 seconds. If the voltage falls below the threshold, the horn chirps for 10ms every 43 seconds until the condition resolves.