RE46C143E16F

Sensor And Detector Interfaces Overview

The RE46C143E16F is a CMOS photoelectric smoke detector ASIC designed for standalone or interconnected fire alarm systems. It operates on a supply voltage range of 5V to 12V with typical standby currents of 4µA at 9V and 5.5µA at 12V. The device features an internal oscillator that powers detection circuitry for 100µs every 8.1 seconds, increasing frequency upon smoke detection. It includes a gain-selectable photo amplifier, low battery monitoring, and chamber integrity checks performed every 40 seconds. The IC supports interconnecting up to 40 detectors via the IO pin and drives piezoelectric horns using a 75% duty cycle temporal tone pattern.

Sensor And Detector Interfaces Feature Summary

• Integrated photoelectric smoke detection with selectable high and normal gain modes for sensitivity adjustment and push-button testing.
• Interconnect capability allowing synchronization of alarms across multiple units within a single system.
• Automated periodic diagnostics for low battery status and photo chamber integrity verification.
• UL recognized per File S24036 for use in smoke detectors complying with UL217 and UL268 specifications.

Sensor And Detector Interfaces Applications

• Standalone photoelectric smoke detectors
• Interconnected residential fire alarm systems
• Commercial smoke sensing devices requiring UL compliance

Sensor And Detector Interfaces Procurement Notes

Verify the specific ordering suffix against the manufacturer's current documentation to confirm package type and environmental compliance. Confirm RoHS Pb-free status if required by design specifications. Ensure the selected variant matches the intended application temperature range and packaging requirements before finalizing procurement 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 PDIP package availability when designing through-hole PCB layouts. Evaluate external component values for ROSC/COSC timing and photo amplifier gain capacitors to meet specific sensitivity and power consumption targets.

Sensor And Detector Interfaces Part Context

The RE46C143 belongs to the R&E International family of smoke detector ASICs, now part of Microchip Technology. It serves as a specialized analog front-end solution for photoelectric sensing, replacing discrete transistor and op-amp designs. This integration reduces bill-of-materials complexity while ensuring consistent performance characteristics across manufacturing batches.

Sensor And Detector Interfaces Replacement Considerations

The datasheet notes compatibility with the Motorola MC145010. Verify pinout and electrical parameter alignment before substituting this legacy component in existing designs.

Sensor And Detector Interfaces FAQ

How does the device handle remote alarm signals?

The bidirectional IO pin detects active high remote signals. Upon detection, the device enters a remote alarm state activating the horn. An internal digital filter provides a nominal 500ms delay to prevent false triggering from pulsed signals.

What is the function of the TEST pin during operation?

Activating the TEST pin invokes a test mode that increases the smoke detection rate to once every 330ms and selects the high gain capacitor. This simulates a smoke condition using background reflections to verify alarm functionality without actual smoke present.

How is the low battery warning indicated?

The device checks battery voltage every 40 seconds. If the voltage falls below the threshold set by external resistors, the horn chirps for 10ms every 40 seconds until the condition is resolved.