MC145017P - Low-Power Ionization Smoke Detector IC | NXP
N.º da peça: MC145017P ✗ Fim de vidaMC145017P Visão geral
An ionization smoke detector is a safety appliance that uses a radiation-based sensing chamber to identify airborne smoke particles. The MC145017 belongs to the sensor and detector interface hierarchy: it accepts an analog signal from the ionization chamber, applies internal detection logic, and controls a piezoelectric alarm. This architecture allows the sensitive ionization chamber, resistive components, and acoustic transducer to remain separate from the monolithic CMOS control circuit.
The principal features of the MC145017P include very low 12 µA supply current, CMOS construction, an ionization-sensor input, a voltage output, and a temporal-pattern horn driver for an external piezoelectric transducer. Low supply current is important in battery-operated alarm systems because the detector electronics and sensing chamber must maintain useful standby and alarm performance without imposing excessive load on the backup battery.
The MC145017 is designed to operate with an ionization chamber and a small number of external components. According to the NXP MC145017 datasheet, the associated circuit is intended for smoke-detector systems designed to comply with UL217 and UL268 specifications. The temporal horn pattern provides an intermittent alarm signal, while the low-power CMOS control section supports battery-powered installations where standby current is a primary design constraint.
Typical applications include residential ionization smoke alarms, commercial smoke-detector modules, and legacy alarm-system replacements that retain the MC145017P pinout. Because the part is listed as obsolete, engineers should treat it primarily as a maintenance component for equipment already built around this device. New smoke-alarm designs should also evaluate current-generation detector ICs against applicable safety requirements rather than assuming an obsolete part can be introduced into a newly certified product.
Circuit design requires careful treatment of the ionization-chamber interface, alarm-driver output, supply decoupling, and test points. Keep sensitive input routing away from the piezoelectric drive path, provide the external components specified by the manufacturer, and verify startup, smoke-entry, alarm-sound, and battery-fallback behavior in the complete detector assembly. The 16-pin PDIP package also requires adequate hole spacing and through-hole assembly clearance on the PCB.
This page consolidates the MC145017P electrical characteristics, package information, application context, and selection considerations into an engineering-focused guide. It also documents the absence of a verified pin-compatible substitute set and highlights the product's obsolete lifecycle status, helping engineers distinguish usable legacy replacements from components that merely perform a similar smoke-detection function.
Alternativas drop-in para MC145017P — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Nenhuma alternativa drop-in disponível para este produto.
Solicitar alternativasMC145017P Especificações
| Product Type | Low-power CMOS ionization smoke detector IC with temporal-pattern horn driver |
| Sensor Input Type | Ionization |
| Tipo de saída | Voltage |
| Corrente de alimentação | 12 µA |
| Temperatura de operação | -10°C to 60°C |
| Encapsulamento | 16-DIP (0.300 inch, 7.62 mm pitch) |
| Terminal Count | 16 terminals |
| Estilo de montagem | Through-hole |
| Packaging | Tube |
| Process Technology | CMOS |
| Power Classification | Low-power device |
| Alarm Output | External piezoelectric transducer driven by internal horn drivers |
| Alarm Pattern | Temporal pattern |
| Required Sensor | External ionization chamber |
| Designed Smoke-System Compatibility | UL217 and UL268 specifications |
Guia de Configuração de Pinos do MC145017P 16-dip (0.300 inch, 7.62 mm pitch)
Configuração de pinos para MC145017P (pacote 16-dip (0.300 inch, 7.62 mm pitch)). A numeração dos pinos, funções e diagramas de conexão estão definidos no datasheet do fabricante. Consulte-o para o footprint exato e diretrizes de soldagem.
Nenhum dado detalhado de pinagem disponível para MC145017P.
Consulte a ficha técnica para a configuração completa dos pinos.
Aplicações típicas
MC145017P é adequado para 6 aplicaçãos: Residential Ionization Smoke Alarm, Commercial Smoke Detector Module, Legacy Alarm-System Maintenance, Battery-Powered Fire-Safety Sensor, Remote Residential Alarm Sensor, Industrial Enclosure Smoke Sensor.
Residential Ionization Smoke Alarm
The MC145017P fits a legacy residential ionization smoke alarm because it combines an ionization-chamber interface, low-power CMOS control logic, and a temporal horn driver in one 16-DIP device. Its 12 µA supply current helps preserve battery life during standby, while the internal alarm drivers energize an external piezoelectric transducer when smoke is detected. Installation in a certified product requires the prescribed chamber, resistor network, test arrangement, and sound-output hardware. Because the MC145017P is obsolete, this application is most appropriate for repairing an existing alarm that already uses its exact pinout rather than launching a newly certified consumer product.
Recomendado
Commercial Smoke Detector Module
The MC145017P can serve as the central detector in a legacy commercial alarm module that uses an ionization chamber and a piezoelectric horn. The 16-pin PDIP construction simplifies through-hole assembly and repair in equipment designed around the original footprint. Its 12 µA supply current supports low standby demand, while the temporal alarm pattern supplies the required intermittent horn signal. The external chamber and acoustic hardware must be arranged to meet the intended UL217 or UL268 system specification. Since the part is obsolete, current commercial designs should verify regulatory and lifecycle requirements before adopting this architecture.
Recomendado
Legacy Alarm-System Maintenance
The MC145017P is most practical as a maintenance component for installed smoke-alarm equipment that already uses its 16-DIP footprint, chamber interface, and temporal horn-driver configuration. A failed IC can be restored without redesigning the enclosure, PCB, or piezoelectric transducer arrangement when a genuine replacement and exact pinout are confirmed. Its low 12 µA supply current is useful when assessing battery endurance in the restored unit. Before installation, verify device markings, pin orientation, supply behavior, chamber calibration, alarm-sound output, and system test results; component interchange without those checks can compromise the safety function.
Recomendado
Battery-Powered Fire-Safety Sensor
The MC145017P is suited to battery-powered ionization fire-sensing equipment where standby consumption is important. Its specified 12 µA supply current helps minimize continuous demand from the control electronics, allowing more capacity to remain available for sensing, self-test, and alarm operation. The device accepts the external ionization-chamber signal and controls an external piezoelectric transducer with a temporal pattern. Designers must still account for the chamber current, quiescent paths, battery leakage, and horn-driver load when calculating service life. For new safety products, a supported detector IC with verified certification is generally preferable to this obsolete component.
Recomendado
Remote Residential Alarm Sensor
The MC145017P can support a remote residential alarm sensor that uses an ionization chamber to detect smoke and a piezoelectric element for local sound. The device's low-power CMOS operation and 12 µA supply-current rating are useful when the sensor must operate for long periods from a limited energy source. Its temporal horn-driver function separates acoustic actuation from the chamber-sensing function, while the DIP package permits straightforward replacement in through-hole legacy hardware. The complete sensor must still be tested for chamber response, false-alarm behavior, test-button operation, sound output, and backup-power capability before deployment.
Recomendado
Industrial Enclosure Smoke Sensor
The MC145017P may be used in a legacy industrial enclosure smoke sensor that requires ionization sensing and a local piezoelectric alarm. The 16-DIP package and external-component architecture allow the chamber and transducer to be placed according to airflow, insulation, and acoustic requirements while the control IC remains on a through-hole PCB. The 12 µA supply current supports low standby demand, but the -10°C to 60°C operating range must be checked against enclosure temperatures. Validate chamber geometry, contamination tolerance, alarm pattern, and applicable industrial safety requirements. For new installations, confirm the obsolete part's availability and consider a currently supported detector platform.
Recomendado
Dados de referência de engenharia para MC145017P — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto |
|---|---|
| Manufacturer | NXP Semiconductors |
| Package | 16-DIP (0.300 inch, 7.62 mm pitch) |
| Mounting Style | Through-hole |
| Product Function | Ionization smoke detector IC with temporal-pattern horn driver |
| Sensor Input | Ionization |
| Output Type | Voltage |
| Supply Current | 12 µA |
| Operating Temperature | -10°C to 60°C |
| Process Technology | CMOS |
| Lifecycle Status | Obsolete |
Principais diferenciais
- Integrated ionization sensing and temporal alarm control (vs MC14538BDTR2G)
- Low standby supply current (vs Generic legacy smoke-detector interface)
- Established legacy package and system orientation (vs MC14536BCP)
Notas de projeto
Route the ionization-chamber signal with short traces, a guarded area, and minimal loop area to reduce susceptibility to EMI and leakage. Keep these sensitive nodes away from the piezoelectric horn-driver traces and switching or power-conversion paths. Use a stable reference ground for the chamber network and follow the grounding arrangement in the manufacturer application schematic. After layout, verify both normal chamber operation and immunity to nearby alarm-drive and supply transients.
Estimate battery endurance from the complete alarm circuit rather than the MC145017P supply current alone. The IC contributes 12 µA, while the chamber, bias network, leakage paths, test circuitry, and piezoelectric transducer can change the system load. Start with Pstandby = VIN × Istandby and divide usable battery energy by measured standby and alarm power. Include battery self-discharge, temperature capacity loss, and end-of-life voltage when establishing the service interval.
Do not substitute the MC145017P with a generic timer, oscillator, or smoke-detector IC merely because its alarm function appears similar. A valid repair part must preserve the 16-DIP pinout, ionization-chamber interface, supply limits, 12 µA-class operating behavior, test circuitry, and temporal piezoelectric drive. Verify device orientation and markings before energizing the board, then perform chamber, self-test, alarm-sound, and power-failure checks on the assembled detector.
The IC package is not the primary thermal concern in a low-power smoke detector, but the piezoelectric transducer and power source may impose separate limits. Check the manufacturer's horn-driver output characteristics before adding series resistance or changing the transducer. If the operating environment exceeds the MC145017P range of -10°C to 60°C, relocate or protect the assembly rather than assuming the through-hole package provides environmental tolerance.
Informações de conformidade
The NXP MC145017 datasheet states that the circuit is designed for smoke-detector systems that comply with UL217 and UL268 specifications. This system-design reference does not establish the MC145017P's own RoHS, REACH, lead-free, halogen-free, conflict-minerals, or automotive qualification status.
