SN75127N - Seven-Channel 5V Line Receiver | Texas Instruments
料号： SN75127N ✗ 停产SN75127N 概述
A line receiver is an interface IC that converts a digital signal arriving through a cable, bus, or wired connection into a clean logic-level output suitable for the next digital circuit. Within the broader semiconductor hierarchy, the SN75127N is a receiver within the interface IC family, where it sits between external wiring and TTL-compatible logic. This makes it useful in legacy computer, peripheral, industrial-control, and communication equipment where a multi-channel receiver offers a simpler implementation than seven discrete receiver circuits.
The primary features are seven receiver channels, operation from one 5 V supply, 20 kΩ input resistance, and compatibility with TTL Schottky-clamped output stages. The IBM 360/370 I/O compatibility cited in the manufacturer documentation indicates that the device was designed for a defined class of high-speed digital interfaces. Its multi-channel organization also reduces package count and simplifies board-level routing when several related lines must be received.
The SN75127N is a bipolar logic interface device whose receiver channels convert incoming digital voltage levels into standard logic signals. Although the available manufacturer-linked material identifies the device as a high-speed receiver, complete timing, propagation-delay, supply-current, and logic-threshold values must be taken from the manufacturer datasheet before final timing-budget and worst-case analysis. Engineers should also account for the effects of cable length, source termination, grounding, and system noise when applying the receiver at the end of a wired interface.
Typical applications include IBM 360/370-compatible peripheral interfaces, TTL-compatible computer equipment, multi-bit data buses, industrial control systems, test equipment, and communications equipment requiring several received logic channels. The seven-channel architecture is particularly useful where parallel data or control lines arrive together and need buffering before reaching TTL logic. A single package can therefore replace repetitive single-channel receiver circuitry where the system already uses compatible voltage levels.
When designing a board around the SN75127N, verify every package pin, logic threshold, enable condition, and propagation delay against the manufacturer datasheet. Keep input and ground-return paths short where practical, maintain compatible logic levels throughout the interface, and avoid treating the receiver as a modern differential line transceiver. These checks are especially important when replacing an older device because footprint compatibility alone does not establish timing or threshold equivalence.
This product page combines the verified device identity, operating characteristics, and application context with practical guidance for replacement, layout, sourcing, and interface design. It also distinguishes documented functions from parameters that require a final datasheet review, helping engineers make a technically defensible decision when maintaining or redesigning a seven-channel TTL-compatible interface.
直接替换替代料： SN75127N ——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SN75127N 规格参数
| Product Type | Seven-channel line receiver |
| Number of Receiver Channels | 7 channels |
| 电源电压 | 5 V |
| Input Resistance | 20 kΩ |
| Output Compatibility | Compatible with TTL Schottky-clamped transistors |
| Interface Standard | IBM 360/370 I/O specification |
| Operating Performance | High speed |
SN75127N standard 引脚配置指南
SN75127N（standard 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： SN75127N.
请参阅 数据手册 以查看完整引脚配置。
典型应用
SN75127N 适用于 6 应用s: IBM 360/370 Peripheral Interfaces, TTL-Compatible Parallel Data Buses, Industrial Control and Instrumentation, Legacy Test Equipment Signal Conditioning, Computer Peripheral and Printer Interfaces, Legacy Communication Equipment.
IBM 360/370 Peripheral Interfaces
The SN75127N is directly aligned with the IBM 360/370 I/O specification cited in the manufacturer documentation, making it suitable for maintaining parallel receiver sections in legacy computer and peripheral equipment. Seven channels can receive a grouped data or control interface from one 5 V supply while presenting TTL Schottky-compatible outputs to the surrounding logic. Engineers should preserve the original interface timing, grounding, and termination arrangement. The advantage is fewer receiver packages and less repetitive routing; the trade-off is dependence on a mature device with limited current sourcing options.
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TTL-Compatible Parallel Data Buses
The seven receiver channels in the SN75127N are useful when a board must recover several parallel data lines from a wired source and present logic-compatible signals to downstream TTL circuitry. The documented 20 kΩ input resistance and single 5 V operation fit systems with multi-line bus structures, while the seven-channel integration simplifies routing compared with seven discrete receiver packages. Signal integrity still depends on source impedance, cable length, return paths, and receiver thresholds, so engineers should confirm the original bus timing before substituting newer buffer architectures.
推荐
Industrial Control and Instrumentation
The SN75127N can support legacy industrial control and instrumentation interfaces that use groups of TTL-compatible signals arriving from external equipment. Its seven channels reduce the number of receiver packages when several command, status, or acknowledgment lines share a common 5 V logic environment. The IBM 360/370-oriented receiver design and 20 kΩ input resistance are particularly relevant to maintenance of older control systems. Engineers should account for ground-potential differences, noise, connector wiring, and propagation timing before deploying the device in a new safety-related or high-noise installation.
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Legacy Test Equipment Signal Conditioning
The SN75127N is appropriate for receiving multiple digital control or measurement-status lines in legacy test equipment built around TTL-compatible logic. Seven channels allow a fixture or instrument interface to consolidate repeated receiver stages while operating from one 5 V rail. The device is specifically documented as a high-speed line receiver with 20 kΩ input resistance, making it suitable for checking the signal path when reconstructing an old instrument interface. Layout engineers should keep receive traces away from switching nodes and use the datasheet pin description to assign the channel inputs and outputs correctly.
推荐
Computer Peripheral and Printer Interfaces
Older computer peripherals and printer-control equipment commonly route multiple logic signals between a controller and an external connector. The SN75127N consolidates seven such receive paths in one package and operates from a single 5 V supply, reducing component count during equipment maintenance. Its TTL Schottky-compatible outputs suit systems built around that logic family, while the IBM 360/370 I/O specification provides a documented compatibility reference. For new designs, engineers should compare this legacy single-ended interface with modern differential transceivers to determine whether isolation or differential noise immunity is required.
推荐
Legacy Communication Equipment
The SN75127N can serve as the receiving element in older communication equipment that terminates several single-ended digital lines into TTL-compatible logic. The seven-channel implementation is useful when a backplane or equipment rack presents parallel command, timing, and response signals through a multi-conductor cable. Its documented 20 kΩ input resistance and 5 V supply operation help engineers map the receiver into an existing interface, while the single-ended implementation remains sensitive to common-mode noise and ground offsets. Shielding, return-path design, and threshold verification are essential when extending or refurbishing these connections.
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推荐产品汇总
工程参考数据： SN75127N ——对比、设计指导和合规信息。
选型指南
设计说明
Assign the SN75127N receiver channels only after comparing the manufacturer pin table with the legacy board schematic. Keep each receive trace short, provide a continuous return path, and route the seven channels away from switching nodes and high-current edges. The receiver’s single-ended architecture is susceptible to differences between signal and ground references, so connector grounding and cable routing can be as important as the logic schematic.
Do not treat an SN75127 as a drop-in replacement solely because it has seven channels. Verify supply voltage, input thresholds, output levels, propagation delay, channel assignment, and package pins against the complete manufacturer datasheet. Also verify the original equipment’s logic family; TTL Schottky compatibility is documented, but that statement alone does not establish compatibility with every modern CMOS or differential interface.
For wired receive lines, preserve the source termination and return-path arrangement used by the original interface. The documented 20 kΩ input resistance influences the effective loading of the source, while long cables can introduce reflections, crosstalk, and ground offsets. Measure the received waveform at the device pins and compare its timing with the downstream system requirements rather than relying only on nominal logic compatibility.
Decouple the 5 V supply locally and use the package pin definitions and recommended layout from the manufacturer datasheet. Because the available product information does not state the device’s supply-current limit, do not calculate or assume power headroom from a generic logic IC value. Confirm the worst-case supply current, voltage tolerance, and bypass requirements before adding other loads to the same 5 V rail.
合规信息
The interface IC is not an automotive-qualified device. RoHS, REACH, lead-free, halogen-free, and conflict-minerals status require confirmation from the manufacturer or current regulatory documentation.