MCZ145012EG

Sensor And Detector Interfaces Overview

The MCZ145012EG is a CMOS photoelectric smoke detector integrated circuit designed for battery-powered applications. It operates within a supply voltage range of 6.0 V to 12.0 V, with an average standby supply current of 8 µA. The device supports an operating temperature range of -10 °C to 60 °C and features ESD and latch-up protection on all pins. It includes variable-gain photo amplifiers, temporal pattern horn drivers, and an I/O pin for interconnected signaling. The component complies with UL217 and UL268 specifications and supports NFPA 72, ANSI S3.41, and ISO 8201 audible emergency evacuation signals.

Sensor And Detector Interfaces Feature Summary

• Variable-gain photo amplifier allows direct interface to IR detectors with gain settings determined by external capacitors.
• Integrated push-pull drivers activate an external piezoelectric transducer for pulsating audible alarms upon detection.
• I/O pin enables wired-OR interconnection of up to 40 units for common signaling or activation of auxiliary devices.
• On-chip monitor circuit periodically checks for degraded chamber sensitivity using high gain during standby.

Sensor And Detector Interfaces Applications

• Smoke detector systems complying with UL217 and UL268 specifications
• Battery-powered fire alarm units requiring low average supply current
• Interconnected smoke detection networks utilizing the I/O pin for common signaling

Sensor And Detector Interfaces Procurement Notes

Verify that the ordering suffix EG corresponds to the lead-free SOICW package as specified in the datasheet. Confirm the manufacturer designation matches Freescale Semiconductor documentation. Ensure the component meets RoHS compliance requirements if applicable to your system design. Cross-reference the part number with official distributor catalogs to validate authenticity and availability status before procurement.

Sensor And Detector Interfaces Selection Notes

Select this IC for applications requiring a dedicated photoelectric smoke detection solution with minimal external components. Consider the 6.0 V to 12.0 V operating voltage range when designing the power supply circuit. Evaluate the need for the I/O pin functionality if remote signaling or multi-unit synchronization is required. Ensure the application environment stays within the specified -10 °C to 60 °C temperature range for optimal performance.

Sensor And Detector Interfaces Part Context

The MCZ145012EG belongs to the MC145012 family of photoelectric smoke detector ICs manufactured by Freescale Semiconductor. This family integrates advanced analog and digital circuitry specifically optimized for infrared photoelectric smoke detection chambers. The EG suffix indicates a lead-free version packaged in a 16-lead SOICW format, distinguishing it from other variants like the PDIP or standard SOIC packages.

Sensor And Detector Interfaces Replacement Considerations

Direct replacements include MC145012ED (Pb-Free PDIP) and MC145012DW (SOICW). Verify pin compatibility and package dimensions when substituting. Functionality remains consistent across Pb-free and non-Pb-free versions per manufacturer specifications.

Sensor And Detector Interfaces FAQ

How does the I/O pin function in a multi-unit setup?

The I/O pin allows up to 40 units to be interconnected for common signaling. It can source current during a local-smoke condition to signal remote smoke to other units or activate escape lights and auto-dialers.

What determines the gain settings of the photo amplifier?

Two external capacitors, C1 and C2, determine the gain settings. Low gain is used in standby, medium gain during local-smoke conditions, and high gain during push-button tests and chamber sensitivity monitoring.

How is a low-supply condition indicated?

A beep or chirp occurring virtually simultaneously with an LED flash indicates a low-supply condition. This occurs when the supply voltage drops below the threshold set by external resistors R6 and R7.