SN75128N - 8-Channel TTL Line Receiver | Texas Instruments
Артикул: SN75128N ✗ Снят с производстваSN75128N Обзор
An eight-channel line receiver is an interface IC that receives digital signals and restores them to valid logic levels for the following logic stage. In the product hierarchy, a line receiver belongs to the interface-IC family, which sits between external signal wiring and digital logic or processing electronics. Unlike a single-ended transceiver, the SN75128N is identified specifically as a receiver, making it relevant where a system needs reliable detection of eight incoming logic signals but does not require a matching driver in the same package.
The SN75128N meets or exceeds the requirements stated for the IBM System 360/370 input/output specification. Its eight-channel organization reduces component count in wide parallel data paths, while the 30 ns receive delay supports communication systems operating at data rates where that propagation interval remains relevant. The single 5 V supply and 53 mA supply current simplify legacy power planning compared with a multi-rail interface design.
Its 20 kΩ input resistance is designed to work with TTL-compatible source circuits, and its outputs are compatible with TTL Schottky-clamped transistor loads. These characteristics make it most applicable to older computer peripheral interfaces, bus-control equipment, instrumentation, and industrial control systems that retain discrete parallel logic rather than modern serial field buses. The device belongs to the interface IC category, not the amplifier, logic, or microprocessor categories.
Typical applications include legacy peripheral bus receivers, parallel status and control links, digital test equipment, industrial control interfaces, and embedded systems communicating with older TTL-compatible logic. Eight independent receive channels are useful when a board needs to bring multiple lines from a cable, backplane, or logic connector into a digital controller while maintaining a common 5 V supply architecture.
The main design consideration is interface compatibility. Confirm that the source voltage levels, cable termination, system timing, and required output rise and fall times agree with the SN75128 family characteristics before placing the device in a new design. Keep interconnect routing short and use an appropriate ground-return path, particularly when long cables or slow edges can allow reflections and noise coupling to distort the received signal.
This product page combines the identified device specifications, package information, lifecycle-related sourcing considerations, interface applications, and engineering guidance into a focused engineering reference. It also distinguishes verified drop-in substitutions from general cross-reference tools, helping designers avoid assuming that a similar line receiver is automatically pin-compatible.
Аналоги без доработки для SN75128N — тот же корпус, pin-to-pin совместимость. Компоненты в других корпусах, требующие переработки PCB, исключены.
Для этого товара нет аналогов без доработки.
Запросить аналогиSN75128N Характеристики
| Device Type | Eight-channel line receiver |
| Number of Channels | 8 channels |
| Напряжение питания | 5 V |
| Ток потребления | 53 mA |
| Receive Propagation Delay | 30 ns |
| Input Resistance | 20 kΩ |
| Output Compatibility | Compatible with TTL Schottky-clamped transistors |
| Power Supply Count | 1 |
| Корпус | 20-pin PDIP |
| Тип монтажа | Through-hole |
| Logic Compatibility | TTL-compatible |
| IBM System 360/370 I/O Compatibility | Meets or exceeds stated requirements |
Руководство по цоколевке SN75128N в корпусе 20-pin pdip
Цоколевка для SN75128N (корпус 20-pin pdip). Нумерация выводов, функции и схемы подключения определены в техническом описании производителя. Обратитесь к нему для точного посадочного места и рекомендаций по пайке.
Нет подробных данных о распиновке для SN75128N.
Обратитесь к даташиту для полной конфигурации выводов.
Типичное применение
SN75128N подходит для 6 применениеs: Legacy Computer Peripheral Bus, Parallel Digital Control Panel, Digital Instrumentation Backplane, Embedded System Legacy Bus Bridge, Printer and Peripheral Interface, Industrial Test Fixture.
Legacy Computer Peripheral Bus
The SN75128N is appropriate for a legacy computer peripheral interface that returns eight parallel TTL-compatible signals to a controller. Its eight-channel organization limits package count, while the 30 ns receive delay provides a defined timing contribution for the bus. The single 5 V supply and 53 mA supply current suit installed equipment built around older TTL logic. Before deployment, verify the source voltage thresholds, connector timing, cable length, and return-ground arrangement against the manufacturer datasheet.
Рекомендуется
Parallel Digital Control Panel
The SN75128N can receive eight status, interlock, or command lines from an operator panel or machine interface. Each of its eight channels operates from the same 5 V rail, which simplifies distribution when the panel already uses TTL-compatible logic. The 20-pin PDIP format is useful for repair-oriented and through-hole industrial equipment. Engineers should budget the 30 ns receive delay in the control sequence and check that every incoming line has a defined state during reset or cable disconnection.
Рекомендуется
Digital Instrumentation Backplane
The SN75128N is suitable for receiving a group of fast-enough parallel status signals in legacy digital instrumentation. Its eight channels and 30 ns receive delay support coordinated sampling of control bits without requiring eight separate receiver packages. A single 5 V supply with 53 mA supply current helps simplify backplane power planning. For bench or laboratory equipment, verify grounding, shielding, source-impedance requirements, and logic thresholds at the cable and connector rather than assuming every TTL source is electrically interchangeable.
Рекомендуется
Embedded System Legacy Bus Bridge
The SN75128N can form the receive side of a bridge between older parallel logic and a modern embedded controller. Eight TTL-compatible inputs support collecting command acknowledgements, status flags, or interrupt lines while the controller handles protocol processing. The 20-pin PDIP package may ease integration into a repairable or retrofit board. The design must preserve the source signal levels and account for the 30 ns receive delay, 53 mA supply current, and possible contention if an external circuit drives an output pin during reset.
Рекомендуется
Printer and Peripheral Interface
The SN75128N fits legacy printer, scanner, and peripheral interfaces that expose several parallel acknowledgement or status lines to a controller. Eight receiver channels reduce the component count when the interface already operates at 5 V TTL levels. The 30 ns propagation delay is short compared with many legacy peripheral buses, but cable skew, connector capacitance, and source rise times still determine the practical margin. Validate the complete interface timing and ensure unused channels are terminated according to the manufacturer recommendations.
Рекомендуется
Industrial Test Fixture
The SN75128N is useful in a legacy industrial test fixture that gathers eight binary measurements from a backplane or tester interface. The common 5 V supply simplifies fixture wiring, and the through-hole 20-pin PDIP package supports serviceable fixture boards. For dependable measurements, use a consistent ground reference between the fixture and source equipment, minimize the loop area of high-impedance logic lines, and confirm that the 20 kΩ input resistance is appropriate for the source circuit. Test every channel for valid inactive states before energizing the fixture.
Рекомендуется
Сводка рекомендуемых товаров
Справочные инженерные данные для SN75128N — сравнение, рекомендации по проектированию и информация о соответствии.
Руководство по выбору
Сравнение с аналогами
| Параметр | Этот товар |
|---|---|
| Brand | Texas Instruments |
| Package | 20-pin PDIP |
| Product Type | Eight-channel line receiver |
| Number of Channels | 8 channels |
| Supply Voltage | 5 V |
| Supply Current | 53 mA |
| Receive Propagation Delay | 30 ns |
| Input Resistance | 20 kΩ |
| Output Compatibility | Compatible with TTL Schottky-clamped transistors |
| Power Supply Count | 1 |
Ключевые отличия
- Eight receive channels in one through-hole package (против SN75128)
- Defined legacy-interface timing (против SN75128)
- Direct compatibility with TTL Schottky-clamped stages (против SN75128)
Заметки по проектированию
Confirm that the external source can drive the SN75128N's 20 kΩ input resistance and that its inactive logic levels meet the receiver thresholds before installation. A logic-compatible label alone does not guarantee reliable operation with every TTL-family source. Check reset states, disconnected-cable behavior, and whether all eight channels require defined levels during power-up.
Budget the 30 ns receive propagation delay along with source-driver delay, interconnect delay, and downstream setup time. Long cables or slow source edges can create reflection and ringing that is more significant than the receiver delay itself. Use a suitable source termination strategy, route the signal and its ground return together, and avoid splitting the return current through a distant ground path.
Place the 20-pin PDIP device in accordance with the manufacturer's pin numbering and keep the signal traces short where possible. A single 5 V rail serving the SN75128N draws 53 mA under the identified conditions; route its supply and return paths to avoid sharing a narrow trace with unrelated switching or inductive loads that could disturb the receiver reference voltage.
Include the receiver's 53 mA supply requirement in the 5 V power budget and provide adequate bypass capacitance near the device according to the application circuit in the manufacturer datasheet. Verify the supply range and sequencing requirements for the exact ordering variant before adding local regulators or load switches. Do not infer a wider voltage range from the nominal 5 V operating condition.
Информация о соответствии
The available records identify the function, electrical characteristics, and package but do not state the regulatory status of the exact SN75128N ordering variant.
