SN65HVD78D - 3.3V 50Mbps Half-Duplex RS-485 | TI
N.º da peça: SN65HVD78D ✓ AtivoSN65HVD78D Visão geral
An RS-485 transceiver is a physical-layer interface IC that combines a differential line driver and receiver for bidirectional data transfer over a balanced bus. The half-duplex arrangement allows the same differential pair to support transmission and reception, although the design must control bus direction so that multiple drivers do not contend on the bus. Within the broader hierarchy, this device is an RS-485 interface IC, a wired-network transceiver, and a semiconductor.
Key features include 50 Mbps maximum signaling, a 3.3 V nominal supply, one driver and one receiver, half-duplex operation, and enhanced ESD protection on the bus pins. The manufacturer describes protection against both Human Body Model and IEC Contact Discharge events. These characteristics distinguish the SN65HVD78D from slower RS-485 transceivers intended for lower-speed industrial multidrop networks.
The combination of a differential driver and receiver on a single 3.3 V supply supports compact point-to-point and multidrop bus implementations. Half-duplex communication reduces the number of signal conductors, while the 50 Mbps capability allows the physical layer to carry high-speed command, measurement, or control traffic. The SOIC-8 package also supports conventional surface-mount assembly and is compatible with automated production equipment.
Typical applications include industrial factory automation, industrial sensor and actuator networks, building-control equipment, robotics, test and measurement systems, and embedded industrial controllers. The device is especially appropriate where a 3.3 V system requires a compact, high-speed RS-485 physical layer and where exposed bus connections increase ESD risk.
Designers should verify driver-enable sequencing, termination, fail-safe behavior, and signal-integrity margins against the complete bus topology. The 3.3 V supply must remain within 3 V to 3.6 V, and exposed RS-485 conductors may still require external surge and common-mode protection beyond the device's specified ESD capability.
This page consolidates manufacturer information, verified distributor listings, drop-in comparison options, and practical design guidance. It distinguishes confirmed ratings from parameters that still require consultation of the complete manufacturer datasheet before production release.
Alternativas drop-in para SN65HVD78D — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Variantes desta série
Modelos da mesma série compatíveis como drop-in com SN65HVD78D (mesmo formato e footprint) — diferindo em Package, Supply Voltage Range.
SN65HVD72D
✅ Drop-In ⚠️ Especificações não verificadasConsulte o preço
Ver ficha técnica →SN65HVD75D
✅ Drop-In ⚠️ Especificações não verificadasConsulte o preço
Ver ficha técnica →SN65HVD30D
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
SN65HVD06D
✅ Drop-In ⚠️ Especificações não verificadasConsulte o preço
Ver ficha técnica →SN75174DW
✅ Drop-In ⚠️ Especificações não verificadasConsulte o preço
Ver ficha técnica →SN65HVD78D Especificações
| Product Type | 3.3 V half-duplex RS-485 transceiver |
| Supply Voltage Range | 3 V to 3.6 V |
| Nominal Supply Voltage | 3.3 V |
| Maximum Signaling Rate | 50 Mbps |
| Driver Count | 1 |
| Receiver Count | 1 |
| Duplex Mode | Half-duplex |
| Bus Standard | RS-485 |
| Encapsulamento | 8-pin SOIC |
| Faixa de temperatura de operação | -40°C to +125°C |
| Tipo de montagem | Surface mount |
| ESD Protection | Human Body Model and IEC Contact Discharge on bus pins |
| IEC Contact Discharge Protection | ±12 kV |
| Fault Protection Voltage | -13 V to +16.5 V |
Guia de Configuração de Pinos do SN65HVD78D 8-pin soic
Configuração de pinos para SN65HVD78D (pacote 8-pin soic). 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 SN65HVD78D.
Consulte a ficha técnica para a configuração completa dos pinos.
Aplicações típicas
SN65HVD78D é adequado para 6 aplicaçãos: Industrial Factory Automation, Robotics and Motion Control, Building Control Networks, Industrial Sensor and Actuator Networks, Test and Measurement Systems, Embedded Communications Hubs.
Industrial Factory Automation
The SN65HVD78D fits high-speed industrial automation links where controllers and distributed I/O must exchange commands over a compact RS-485 network. Its 50 Mbps capability provides substantial bandwidth for short factory-floor connections, while the 3.3 V supply integrates directly with 3.3 V embedded controllers. The differential driver and receiver improve signal integrity and noise immunity on balanced wiring. Bus-pin ESD protection is especially useful around machinery and cable entry points, but the 120 mV-level receiver margins and 50 Mbps rate should be validated against actual cable length, topology, and common-mode environment.
Recomendado
Robotics and Motion Control
The SN65HVD78D supports compact half-duplex communication between a robot controller and remote motion-control modules. A 50 Mbps physical layer can carry frequent position, status, and diagnostic traffic on short cables, while the differential signaling reduces susceptibility to industrial noise. The SOIC-8 format preserves PCB area, and the 3.3 V operation aligns with many embedded processors. Engineers should use controlled-direction logic to prevent simultaneous transmission, maintain proper bus termination, and verify that reflected data and ground offsets remain within the receiver's supported conditions.
Recomendado
Building Control Networks
The SN65HVD78D is suitable for building-control equipment that needs a low-power, high-speed physical layer over balanced copper cabling. Its 3 V to 3.6 V operating range supports embedded building controllers, and the 50 Mbps rate allows one physical layer to serve measurement, configuration, and diagnostic traffic. Differential signaling is useful in environments containing lighting, motors, and switching power supplies. For installations with long cables or large ground-potential differences, an isolated interface such as ISO1432DWR may provide a more suitable galvanic barrier than the non-isolated transceiver.
Recomendado
Industrial Sensor and Actuator Networks
The SN65HVD78D can connect a controller to distributed sensors, actuators, and data-acquisition modules operating on a shared RS-485 bus. The 50 Mbps capability is valuable where short branch lengths and frequent updates create a high aggregate traffic demand, while one driver and one receiver support half-duplex multidrop communication with bus-direction control. ESD protection on the bus pins adds resilience where sensors are cabled outside an enclosure. The final network must still be engineered for termination, stub length, grounding, and protection from surge or industrial transients.
Recomendado
Test and Measurement Systems
The SN65HVD78D suits compact test and measurement controllers that exchange commands, results, and calibration data with remote instruments. At up to 50 Mbps, the physical layer can handle high-volume data without requiring a separate high-speed differential standard. Its 3.3 V operation is convenient for compact control boards, and the 8-pin SOIC package simplifies assembly. When the remote instrument is connected through a long cable or has a substantially different ground reference, isolation and external surge protection become important because the transceiver itself is a non-isolated interface.
Recomendado
Embedded Communications Hubs
The SN65HVD78D can serve as the high-speed RS-485 physical layer in an embedded communications hub or industrial gateway. A 50 Mbps bus allows a controller to aggregate short-distance field traffic while the 3.3 V transceiver supply fits directly alongside modern embedded processors. The SOIC-8 footprint conserves board area, and the differential bus is more tolerant of common-mode noise than a single-ended interface. Direction control, thermal margin, connector surge exposure, and the number of attached nodes should be validated before using the device in a permanently installed gateway.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para SN65HVD78D — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | SN65HVD72D | SN65HVD75D | SN65HVD30D | SN65HVD06D | SN75174D |
|---|---|---|---|---|---|---|
| Package | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
Principais diferenciais
- Higher signaling rate than the lower-speed SN65HVD06D (vs SN65HVD06D)
- Documented IEC Contact Discharge protection on bus pins (vs SN75174D)
- Wide industrial temperature operation (vs SN65HVD72D)
Notas de projeto
Route the transceiver and connector interface as a controlled differential pair. Keep the A and B traces closely coupled, use a continuous reference plane, minimize stub branches, and place any termination component close to the driver rather than at the far cable end. For high-speed operation, avoid splitting the return-current path beneath the pair and check the complete board-plus-cable channel because the 50 Mbps rating does not guarantee reliable operation over every cable length.
A half-duplex RS-485 bus requires disciplined enable control. Ensure the driver is disabled whenever a node is receiving, and prevent multiple nodes from driving the bus simultaneously. Include a defined fail-safe strategy for an idle or disconnected bus, and verify the receiver output state during startup, reset, cable faults, and driver disable. The SN65HVD78D's ESD protection does not replace these protocol and contention safeguards.
Provide local supply decoupling and a low-impedance return from the transceiver ground pins to the connector and cable shield. ESD protection is specified on the bus pins, but external TVS or surge-protection devices may be needed for severe industrial or outdoor transients. Select those devices for the working voltage, line capacitance, and pulse requirements, and verify that protection-network capacitance does not distort the 50 Mbps signal.
Informações de conformidade
The supplied excerpts confirm IEC Contact Discharge protection for the bus pins but do not provide verified RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals declarations. Compliance must be confirmed from the current manufacturer product page and material declarations.
