MC14556BD - 1-of-4 CMOS Decoder/Demultiplexer | Motorola
料号： MC14556BD ✓ 量产中MC14556BD 概述
A decoder/demultiplexer is a logic device that converts binary selection information into one active output path. This makes the MC14556BD useful for control, address decoding, peripheral selection, data routing, and test-point multiplexing. Its four outputs are designed so that only one selected output is active for a valid select combination while the enable input provides an additional gating function. The complementary MOS construction places the device in the 4000-series CMOS logic family.
The principal electrical characteristics are a 3 V to 18 V supply range, low-power CMOS operation, and an active-low enable control. The package is a 16-SOIC, also described in listings as SOIC-16 or PDSO16, with a body width of 3.90 mm and a nominal 0.154 inch lead pitch. The operating-temperature range of -55 °C to 125 °C supports industrial and extended-temperature equipment where the additional qualification and sourcing requirements are satisfied.
The MC14556BD can decode a two-bit command into one of four mutually exclusive destinations, making it appropriate for selecting one sensor, switching one bank of loads, directing a signal path, or controlling a group of digital peripherals. Because it is a demultiplexer, the enable input can inhibit output activity during reset, initialization, or shared-bus conditions. Designers should account for propagation delay and output transition timing when operating at high system clock rates.
For reliable PCB implementation, place the device close to the signals it decodes, route the enable and select nets away from noisy switching nodes, and maintain a common ground reference between the logic device and connected circuitry. Use the manufacturer pin-description and logic diagrams when assigning PCB tracks because the available product documentation does not reproduce a verified pin-by-pin connection table here.
This product page combines the device’s verified function, supply range, package, temperature range, and sourcing information with application guidance, comparison parameters, and practical design notes. The result helps engineers identify whether the MC14556BD fits a new decoder/demultiplexer design or whether a different logic function is required.
直接替换替代料： MC14556BD ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
该产品暂无直接替换替代料。
请求替代料MC14556BD 最大额定值与电气特性
| Device Type | Dual binary to 1-of-4 decoder/demultiplexer |
| Logic Family | CMOS 4000 series |
| Construction | Complementary MOS enhancement-mode devices |
| Supply Voltage Range | 3 V to 18 V |
| Number of Select Inputs | 2 |
| 输出数量 | 4 mutually exclusive outputs |
| Enable Polarity | Active-low |
| 输出类型 | Inverted output |
| 封装 | 16-pin SOIC |
| Package Designation | PDSO16 |
| Body Width | 3.90 mm |
| Lead Pitch | 0.154 inch |
| 安装类型 | Surface mount |
| 工作温度范围 | -55 °C to 125 °C |
| Product Status | Active |
MC14556BD pdso16 引脚配置指南
MC14556BD（pdso16 封装）的引脚配置。 该数字 IC 包含 GPIO、通信接口（UART、SPI、I2C）和电源引脚。请参阅制造商数据手册以了解复用引脚功能和配置选项。对嵌入式系统设计和 PCB 布局至关重要。
暂无详细引脚数据： MC14556BD.
请参阅 数据手册 以查看完整引脚配置。
典型应用
MC14556BD 适用于 6 应用s: Peripheral Address Decoding, Industrial Relay and Load Selection, Sensor Channel Selection, Data Routing and Test Point Multiplexing, Communication Interface Control, Sequenced Power and Resource Control.
Peripheral Address Decoding
The MC14556BD is well suited to decoding a two-bit address into one of four mutually exclusive destination selections. Place it near the target peripherals and drive A and B from control logic, while the active-low E input can inhibit decoding during reset or initialization. Its 3 V to 18 V supply range supports varied industrial logic rails, and the 16-pin SOIC package simplifies routing to four destination signals. Confirm propagation delay and output timing in the manufacturer datasheet when the select lines change near a system clock edge.
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Industrial Relay and Load Selection
Use the MC14556BD to route a shared control function toward one of four load channels when each channel requires a mutually exclusive selection path. The active-low enable input can inhibit all selected outputs during fault, reset, or maintenance intervals, while the two select inputs identify the destination. Its -55 °C to 125 °C listed operating range is useful in extended-temperature equipment, but the final load drivers must provide isolation, current capacity, and appropriate fault protection. Validate output voltage levels against the selected load-driver technology.
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Sensor Channel Selection
The MC14556BD can implement a four-way selection stage for a sensor interface when only one of several measurement channels should be active at a time. Two select bits determine the requested channel, and the active-low enable provides a clean inhibit mechanism during sensor reset or calibration. The 3 V to 18 V operating range supports both low-voltage sensor systems and higher-voltage control logic, subject to input-threshold compatibility. Confirm output rise and fall times so the selected channel changes do not create unintended transient signals.
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Data Routing and Test Point Multiplexing
Use the MC14556BD as a four-channel routing element in a controlled test or measurement system where a single command must select one of several signal paths. The two select inputs and active-low enable allow the central controller to isolate destinations and suppress activity during setup. Because the device is a logic decoder/demultiplexer rather than an analog multiplexer, it should drive control inputs or gates rather than pass high-bandwidth analog signals directly. Verify timing, output drive, and fan-out against the driven network.
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Communication Interface Control
The MC14556BD can help organize discrete control signals in communication equipment by selecting one of four mutually exclusive destinations, such as request lines, mode indicators, or transceiver control functions. Its CMOS 4000-series implementation operates from 3 V to 18 V, enabling use across several industrial voltage domains when levels are compatible. The active-low enable assists with coordinated reset, and the 16-pin SOIC package provides enough pins for the select, enable, outputs, and supply connections. Validate timing against the surrounding interface specification.
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Sequenced Power and Resource Control
The MC14556BD can decode a two-bit control word into one of four mutually exclusive enable or selection signals for sequential subsystem control. The active-low enable input provides a master inhibit path, allowing the controller to hold all destinations inactive during initialization. Although the output voltage levels must remain compatible with downstream control inputs, the 3 V to 18 V supply range and surface-mount SOIC package make the device suitable for board-level logic. Confirm power-up behavior and output timing before using it to sequence sensitive circuitry.
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推荐产品汇总
工程参考数据： MC14556BD ——对比、设计指导和合规信息。
选型指南
设计说明
Do not assume that a generic 74-series decoder is interchangeable with the MC14556BD. Confirm the 16-pin SOIC footprint, active-low enable behavior, inverted output convention, supply range, and timing limits before reusing a PCB. The active-low enable must be driven to its inactive level during reset, and unused inputs must not be left floating.
Place the MC14556BD close to the select, enable, and decoded destination nets to minimize trace delay and susceptibility to coupled noise. Keep the ground return continuous under the device, provide the required bypassing close to the supply pins, and route output traces away from high-current switching paths. Use the manufacturer package drawing for the final land pattern and pin-one orientation.
Evaluate output transition time and propagation delay against the slowest receiving circuit. The decoder can switch only one output at a time, but shared select or enable traces can still introduce timing skew if long or heavily loaded. Use short traces, appropriate fan-out, and a clean logic reference; add isolation or buffering when driving remote loads or crossing a significant ground-potential boundary.
Operate the MC14556BD only within its 3 V to 18 V supply range and observe the manufacturer input-voltage limits. Do not allow unused or disabled outputs to be treated as guaranteed high-impedance nodes unless the datasheet defines that state. When the active-low enable disables the decoder, verify whether any output remains actively driven before connecting it to a sensitive downstream control input.
合规信息
The available product information identifies the MC14556BD as an active CMOS logic IC but does not state RoHS, REACH, lead-free, halogen-free, or conflict-minerals status.