MC14551BF - 280 Ohm Quad 2:1 Analog Switch | onsemi
料号： MC14551BF ✓ 量产中MC14551BF 概述
An analog multiplexer is a semiconductor interface that uses digital control signals to select one of multiple analog inputs and connect it to a shared output. A multiplexer and demultiplexer can also reverse this function, allowing a common line to be routed to a selected destination. The MC14551BF belongs to the analog switch and multiplexer hierarchy within interface ICs and provides multiple switching functions in one package.
Key features include a 2:1 configuration for each of four circuits, a 280 ohm ON resistance, low OFF leakage, and control inputs protected by triple diode protection. The device supports a 3.0 Vdc to 18 Vdc supply range, while its analog signal range extends across the VDD-to-VEE span. These characteristics support both positive-supply and dual-supply signal-routing arrangements when the circuit is operated within its specified limits.
The MC14551BF uses independent address and enable controls to determine which paired input reaches each multiplexer output. This arrangement allows a microcontroller or programmable logic device to scan sensors, sample multiple measurement channels, isolate instrumentation paths, or route signals to converters. Its four switching sections are organized as a 4PDT solid-state switch, providing a compact way to implement several analog routing functions on one board.
Typical uses include data acquisition systems, automated test equipment, programmable signal conditioning, industrial control interfaces, and multichannel sensor acquisition. The 280 ohm ON resistance is most appropriate for moderate-impedance analog paths where switching loss and input loading remain acceptable. For very high-impedance sources, the selected switch's capacitance, leakage, and settling behavior require validation in the complete signal chain.
Design the PCB with short analog traces, a solid ground reference, and decoupling placed close to VDD and VEE. Account for injected charge and off-state leakage when switching between sources at different potentials. Avoid exceeding the device's maximum rated voltages, and verify control logic levels across the full supply range before using the multiplexer's address and enable inputs.
This product page consolidates the exact MC14551BF identification, package details, technical specifications, sourcing information, selection guidance, and design considerations into one engineering reference. It also distinguishes confirmed drop-in-family options from unrelated interface ICs, helping PCB designers evaluate footprint reuse without confusing electrical equivalence with functional similarity.
直接替换替代料： MC14551BF ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
MC14551B
✅ 直接替换📋 参考替代料（不在目录中）
MC14551BF 最大额定值与电气特性
| Number of Circuits | 4 circuits |
| Switch Configuration | 2:1 per circuit |
| ON Resistance | 280 ohm |
| Internal Switch Configuration | 4PDT solid-state switch |
| Supply Voltage Range | 3.0 Vdc to 18 Vdc |
| Control Input Protection | Triple diode protection |
| OFF Leakage Current | Very low; 100 nA maximum listed rating |
| 封装 | 16-pin SOIC, 16-SOEIAJ |
| 引脚数量 | 16 pins |
| 安装类型 | Surface mount |
MC14551BF 16-pin soic, 16-soeiaj 引脚配置指南
MC14551BF（16-pin soic, 16-soeiaj 封装）的引脚配置。 引脚编号、功能和连接图在制造商数据手册中定义。请参阅该手册以了解确切的封装尺寸和焊接指南。
暂无详细引脚数据： MC14551BF.
请参阅 数据手册 以查看完整引脚配置。
典型应用
MC14551BF 适用于 6 应用s: Multichannel Data Acquisition, Programmable Test Signal Routing, Industrial Sensor Interface, Programmable Signal Conditioning, Audio and Communication Signal Routing, Digital Control Interface Switching.
Multichannel Data Acquisition
The MC14551BF fits multichannel data-acquisition systems that route several sensor or test inputs into a shared converter channel. Each of its four 2:1 sections can place one of two inputs on a common output, allowing a microcontroller to scan paired sources without requiring a separate switch package for every signal. The 280 ohm ON resistance is suitable for many moderate-impedance sensor paths, while low OFF leakage helps preserve the selected source when the mux is inactive. Designers should still validate converter input capacitance, source impedance, acquisition time, and injected-charge settling for the selected channel.
Programmable Test Signal Routing
The four-channel structure of the MC14551BF is useful in automated test equipment for alternating between reference and measurement paths. Each 2:1 circuit provides a simple way to connect either of two nodes to a common instrument channel, reducing the number of discrete relays or switches required around an analog front end. The onsemi MC14551B datasheet identifies low ON impedance and very low OFF leakage as core switch characteristics, which support predictable path isolation. Instrument designers should verify bandwidth, capacitance-driven settling, control timing, and maximum voltage against the exact test-node amplitudes.
Industrial Sensor Interface
MC14551BF can consolidate paired inputs from industrial sensors into shared processing electronics. A 3.0 Vdc to 18 Vdc supply range supports unipolar interface designs, and the four independent 2:1 channels make the device useful when each sensor group has two selectable sources. The low OFF leakage is advantageous when inactive channels connect to high-impedance transducers, whereas the 280 ohm ON resistance must be included in divider and loading calculations. For thermocouples, strain bridges, or capacitive sensors, engineers should confirm common-mode range, leakage effects, settling, and sensor-specific accuracy requirements.
Programmable Signal Conditioning
The MC14551BF can implement channel selection ahead of an analog amplifier or converter in programmable signal-conditioning systems. Two sources per section allow a controller to substitute calibration, diagnostic, or filtered signals without mechanically changing the signal path. Its four-channel organization permits several such selections in one package, while the 280 ohm ON resistance is compatible with many ordinary signal-conditioning impedances. Precision designs should confirm the switch's contribution to noise, channel capacitance, OFF isolation, and settling time, particularly when the source impedance is much greater than 280 ohm.
Audio and Communication Signal Routing
The MC14551BF may route low-frequency analog signals between functional blocks in audio, communications, or interface equipment, subject to the device's voltage and bandwidth limits. Its four 2:1 sections allow source selection for multiple baseband or control paths, and the low OFF leakage helps prevent an inactive source from loading the active channel. Because the listed 280 ohm ON resistance can create loss with low-impedance circuits and its capacitance can limit high-frequency performance, designers should use the onsemi MC14551B datasheet to confirm bandwidth, distortion, and switching characteristics for the intended signal level.
Digital Control Interface Switching
The MC14551BF can be used as a digitally controlled routing element between external analog circuitry and a host controller. Its address and enable controls allow firmware to select signal paths, isolate sections, or implement measurement sequences without adding another bus-controlled switch package. Triple-diode protection on all control inputs improves robustness against excessive control-pin stress, although it does not remove the need to observe absolute maximum ratings. Firmware should account for finite switching and settling behavior, and hardware should route sensitive analog nodes away from switching edges and control traces.
工程参考数据： MC14551BF ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | MC14551B |
|---|---|---|
| Package | SOIC-16 (16-SOEIAJ) | SOIC-16 family configuration |
| Brand | onsemi | onsemi |
| Number of Circuits | 4 circuits | 4 circuits |
| Switch Configuration | 2:1 per circuit | 2:1 per circuit |
| Internal Configuration | 4PDT solid-state switch | 4PDT solid-state switch |
| ON Resistance | 280 ohm | 280 ohm |
| Supply Voltage Range | 3.0 Vdc to 18 Vdc | 3.0 Vdc to 18 Vdc |
| Control Input Protection | Triple diode protection | Triple diode protection |
| OFF Leakage Current | Very low; 100 nA maximum listed rating | Very low; 100 nA maximum listed rating |
关键差异点
- Four independent 2:1 paths in one package （对比 MC14551B)
- Broad operating supply range （对比 MC14551B)
- Control-pin robustness （对比 MC14551B)
设计说明
Place the VDD and VEE decoupling components close to their corresponding pins, and provide a low-impedance ground connection to the device. Keep each common output and its paired analog inputs on a compact routing group to minimize parasitic capacitance and coupling from adjacent channels. Follow the manufacturer land pattern for the 16-SOEIAJ SOIC package, including the correct pin-1 orientation, and confirm copper clearance around the body and lead tips.
Include the 280 ohm ON resistance when calculating attenuation, source loading, and downstream input range. For a source with impedance Rs, the simple resistive divider formed by Rs and 280 ohm can reduce the selected signal before it reaches the next stage. In high-impedance systems, also evaluate OFF leakage, switch capacitance, and injected charge. These effects become more important when the signal-to-noise ratio requirement or settling time is tight.
Do not treat the 3.0 Vdc to 18 Vdc supply range as permission to exceed the absolute maximum ratings. Check whether the analog signal can remain within the VDD-to-VEE span under every operating state, and verify select and enable logic levels over the full supply range. When switching between sources at different potentials, confirm that the resulting voltage difference and transient charge remain within the device's operating limits.
合规信息
The exact MC14551BF ordering configuration should be checked against current onsemi product declarations and quality documents. The MC14551BFEL lead-free ordering designation is visible in a cross-reference result, but that designation alone is not used as the compliance declaration for MC14551BF.
